Sample records for resonant third-integer extraction

  1. Third interger resonance slow extraction schemem for a mu->e experiment at Fermilab

    SciTech Connect

    Nagaslaev, V.; Amundson, J.; Johnstone, J.; Michelotti, L.; Park, C.S.; Werkema, S.; /Fermilab; Syphers, M.; /Michigan State U.

    2010-09-01

    The current design of beam preparation for a proposed mu->e conversion experiment at Fermilab is based on slow resonant extraction of protons from the Debuncher. The Debuncher ring will have to operate with beam intensities of 3 x 10{sup 12} particles, approximately four orders of magnitude larger than its current value. The most challenging requirements on the beam quality are the spill uniformity and low losses in the presence of large space charge and momentum spread. We present results from simulations of third integer resonance extraction assisted by RF knock-out (RFKO), a technique developed for medical accelerators. Tune spreads up to 0.05 have been considered.

  2. Third interger resonance slow extraction scheme for a mu->e experiment at Fermilab

    E-print Network

    Nagaslaev, V; Johnstone, J; Michelotti, L; Park, C S; Werkema, S; Syphers, M

    2012-01-01

    The current design of beam preparation for a proposed mu->e conversion experiment at Fermilab is based on slow resonant extraction of protons from the Debuncher. The Debuncher ring will have to operate with beam intensities of 3 x 10**12 particles, approximately four orders of magnitude larger than its current value. The most challenging requirements on the beam quality are the spill uniformity and low losses in the presence of large space charge and momentum spread. We present results from simulations of third integer resonance extraction assisted by RF knock-out (RFKO), a technique developed for medical accelerators. Tune spreads up to 0.05 have been considered.

  3. Development of signal-extraction scheme for Resonant Sideband Extraction

    E-print Network

    K. Kokeyama; K. Somiya; F. Kawazoe; S. Sato; S. Kawamura; A. Sugamoto

    2008-05-26

    As a future plan, an advanced gravitational-wave detector will employ an optical configuration of resonant sideband extraction (RSE), achieved with an additional mirror at the signal-detection port of the power-recycled Fabry-Perot Michelson interferometer. To control the complex coupled cavity system, one of the most important design issues is how to extract the longitudinal control signals of the cavities. We developed a new signal-extraction scheme which provides an appropriate sensing matrix. The new method uses two sets of sidebands: one of the sideband components satisfies the critical coupling ondition for the RSE interferometer and reaches the signal-extraction port, and the other sideband is completely reflected by the Michelson interferometer. They provide a diagonalized sensing matrix and enable the RSE control to be robust.

  4. Wave energy extraction by coupled resonant absorbers.

    PubMed

    Evans, D V; Porter, R

    2012-01-28

    In this article, a range of problems and theories will be introduced that will build towards a new wave energy converter (WEC) concept, with the acronym 'ROTA' standing for resonant over-topping absorber. First, classical results for wave power absorption for WECs constrained to operate in a single degree of freedom will be reviewed and the role of resonance in their operation highlighted. Emphasis will then be placed on how the introduction of further resonances can improve power take-off characteristics by extending the range of frequencies over which the efficiency is close to a theoretical maximum. Methods for doing this in different types of WECs will be demonstrated. Coupled resonant absorbers achieve this by connecting a WEC device equipped with its own resonance (determined from a hydrodynamic analysis) to a new system having separate mass/spring/damper characteristics. It is shown that a coupled resonant effect can be realized by inserting a water tank into a WEC, and this idea forms the basis of the ROTA device. In essence, the idea is to exploit the coupling between the natural sloshing frequencies of the water in the internal tank and the natural resonance of a submerged buoyant circular cylinder device that is tethered to the sea floor, allowing a rotary motion about its axis of attachment. PMID:22184664

  5. Temporal feature extraction in photorefractive resonators

    NASA Astrophysics Data System (ADS)

    Anderson, Dana Z.; Zhou, Gan; Montemezzani, Germano

    1994-12-01

    A holographic optical system listens to an incoming signal and extracts the most common repetitive temporal features of that signal. An example might be to extract the features of Morse code, which consists of two tone lengths and two pause lengths. This optical system is self-organizing, in that very little a priori information is imbeded in the system to indicate what form the temporal signals take. The primary constraints imposed on the signal is: (1) finite bandwidth; (2) limited feature duration; and (3) rates of reoccurrence. The optical apparatus uses a photorefractively pumped multimode optical oscillator having a delay line in the feedback loop. The delay line serves to translate the temporal dimension into a spatial one, and it also builds into the system a notion of the direction of time. Temporal feature extraction takes place as a competitive interaction among sets of modes, which are termed chronomodes. Experiments illustrate the principles of such a system by extracting the two most probable temporal features from a signal imposed on a laser beam.

  6. AGS slow extracted beam improvement

    SciTech Connect

    Marneris, I.; Danowski, G.; Sandberg, J.; Soukas, A.

    1997-07-01

    The Brookhaven AGS is a strong focusing accelerator which is used to accelerate protons and various heavy ion species to an equivalent proton energy of 29 GeV. Since the late 1960`s it has been serving high energy physics (HEP - proton beam) users of both slow and fast extracted beams. The AGS fixed target program presently uses primary proton and heavy ion beams (HIP) in slowly extracted fashion over spill lengths of 1.5 to 4.0 seconds. Extraction is accomplished by flattoping the main and extraction magnets and exciting a third integer resonance in the AGS. Over the long spill times, control of the subharmonic amplitude components up to a frequency of 1 kilohertz is very crucial. One of the most critical contributions to spill modulation is due to the AGS MMPS. An active filter was developed to reduce these frequencies and it`s operation is described in a previous paper. However there are still frequency components in the 60-720 Hz sub-harmonic ripple range, modulating the spill structure due to extraction power supplies and any remaining structures on the AGS MMPS. A recent scheme is being developed to use the existing tune-trim control horizontal quadrupole magnets and power supply to further reduce these troublesome noise sources. Feedback from an external beam sensor and overcoming the limitations of the quadrupole system by lead/lag compensation techniques will be described.

  7. Antioxidant activity of grape skin aqueous extracts from pressurized hot water extraction combined with electron paramagnetic resonance spectroscopy.

    PubMed

    S?avíková, Lenka; Polovka, Martin; Hohnová, Barbora; Karásek, Pavel; Roth, Michal

    2011-09-30

    Pressurized hot water extraction (PHWE) was employed to prepare extracts from dried grape skin of two wine grape varieties (St. Laurent and Alibernet) at various temperatures (from 40 up to 120°C) and amounts of sample (0.5, 1.0 and 1.5 g). To assess the antioxidant activity of the extracts, electron paramagnetic resonance (EPR) spectroscopy was applied involving DPPH and ABTS(+) assays. Other extract characteristics including HPLC profile of anthocyanins and total phenolic compound content were obtained as well. PHWE has also been compared with earlier results of extractions of the same grape skin samples with compressed methanol and compressed ethanol under the conditions of pressurized fluid extraction (PFE). From this comparison, PHWE emerges as the more benign and efficient extraction method to recover valuable phenolic antioxidants from grape skins for the prospective use in functional food supplements. PMID:21872083

  8. Two-dimensional analyses related to wave-energy extraction by submerged resonant ducts

    Microsoft Academic Search

    James Lighthill

    1979-01-01

    It is pointed out that submerged resonant ducts offer an approach to the design of wave-energy extraction devices consistent with the need for maximum seaworthiness. A full account is provided of one type of analysis of these systems, based upon two-dimensional wave hydrodynamics and linearized duct dynamics. One theoretical prediction is that the effective pressure fluctuations to which a resonant

  9. Offline combination of pressurized fluid extraction and electron paramagnetic resonance spectroscopy for antioxidant activity of grape skin extracts assessment.

    PubMed

    Polovka, Martin; S?avíková, Lenka; Hohnová, Barbora; Karásek, Pavel; Roth, Michal

    2010-12-17

    A comprehensive characterization of grape skin methanolic and ethanolic extracts prepared by pressurized fluid extraction (PFE) at various temperatures within 40 to 120°C from two wine grape varieties, St. Laurent and Alibernet was performed. For the first time, an offline combination of PFE and electron paramagnetic resonance (EPR) spectroscopy together with other experimental methods was employed to assess the effect of extraction conditions on numerous extract characteristics including antioxidant or radical-scavenging ability, HPLC profile of anthocyanins, total phenolic compounds content (TPC), tristimulus color values (CIE Lab), and pH values. The properties of extracts depend on the solvent used, the mass of grape skins as well as on the extraction conditions among which the temperature plays a crucial role. In spite of wide interval of extraction temperatures, all extracts still retain their antioxidant and/or radical-scavenging properties, indicating that the extracts prepared by PFE can serve as potential source of functional food supplements or color enhancers. PMID:20810124

  10. Extraction of P11 Resonance from pi-N Data and Its Stability

    SciTech Connect

    S. X. Nakamura, H. Kamano, T.-S. H. Lee, T. Sato

    2011-09-01

    An important question about resonance extraction is how much resonance poles and residues extracted from data depend on a model used for the extraction, and on the precision of data. We address this question with the dynamical coupled-channel (DCC) model developed in Excited Baryon Analysis Center (EBAC) at JLab. We focus on the P11 pi-N scattering. We examine the model-dependence of the poles by varying parameters to a large extent within the EBAC-DCC model. We find that two poles associated with the Roper resonance are fairly stable against the variation. We also develop a model with a bare nucleon, thereby examining the stability of the Roper poles against different analytic structure of the P11 amplitude below pi-N threshold. We again find a good stability of the Roper poles.

  11. Improved ion extraction from an electron cyclotron resonance ion source by a metal-dielectric-extraction electrode

    SciTech Connect

    Schachter, L.; Dobrescu, S.; Stiebing, K.E. [National Institute for Physics and Nuclear Engineering (IFIN-HH), P.O. Box MG-6, Bucharest (Romania); Institut fuer Kernphysik der Johann Wolfgang Goethe-Universitaet (IKF), Max-von-Laue-Strasse 1, D-60438 Frankfurt (Germany)

    2006-03-15

    The goal of the experiment was to study the influence and the physics of the boundary region (between the plasma and the extraction potential) with direct impact on the source ion-beam output. A specially processed high-emissive metal-dielectric structure was installed on the extraction electrode of the Frankfurt 14 GHz electron cyclotron resonance ion source (ECRIS), forming a so-called metal-dielectric- (MD) extraction electrode. The emissive layer of the disk faced the plasma; its inner hole was about the size of the normal extraction hole of the ECRIS. The output of the ECRIS in the presence of the MD electrode was compared with the outputs for the standard configuration (overall stainless-steel plasma chamber) and with the same plasma chamber with the radial wall covered by a highly electron emissive MD liner that raise the plasma electron density and temperature. The charge state distributions of the argon ions extracted from the source show an important increase of the ion beam for the high charge states as compared to the standard situation whereas the low charge states are less reduced than in the case of the presence of a MD liner. Due to the special position of the dielectric layer, the MD electrode introduces a new effect, which is connected to its property of becoming a positively charged surface under electron and ion bombardment. The MD electrode creates a quasiconfinement of the peripheral ions in the extraction, those ions that are normally lost to a conducting extraction electrode.

  12. Extracting kinetic rate constants from surface plasmon resonance array systems

    Microsoft Academic Search

    Rebecca L. Rich; Michelle J. Cannon; Jerry Jenkins; Prabhakar Pandian; Shankar Sundaram; Rachelle Magyar; Jennifer Brockman; Jeremy Lambert; David G. Myszka

    2008-01-01

    Surface plasmon resonance imaging systems, such as Flexchip from Biacore, are capable of monitoring hundreds of reaction spots simultaneously within a single flow cell. Interpreting the binding kinetics in a large-format flow cell presents a number of potential challenges, including accounting for mass transport effects and spot-to-spot sample depletion. We employed a combination of computer simulations and experimentation to characterize

  13. Baryon resonance extraction from {pi}N data using a unitary multichannel model.

    SciTech Connect

    Vrana, T. P.; Dytman, S. A.; Lee, T.-S. H.; Physics; Univ. of Pittsburgh

    2000-01-01

    A unitary multi-channel approach, first developed by the Carnegie-Mellon Berkeley group, is applied to extract the pole positions, masses, and partial decay widths of nucleon resonances from the partial wave amplitudes for the transitions from {pi}N to eight possible final baryon-meson states. Results of single energy analyses of the VPI group using the most current database are used in this analysis. A proper treatment of threshold effects and channel coupling within the unitarity constraint is shown to be crucial in extracting resonant parameters, especially for the resonance states, such as S{sub 11}(1535), which have decay thresholds very close to the resonance pole position. The extracted masses and partial decay widths of baryon resonances up to about 2 GeV mass are listed and compared with the results from previous analyses. In many cases, the new results agree with previous analyses. However, some significant differences, in particular for the resonances that are weakly excited in {pi}N reactions, are found.

  14. Magnification of photonic crystal fluorescence enhancement via TM resonance excitation and TE resonance extraction on a dielectric nanorod surface.

    PubMed

    Wu, Hsin-Yu; Zhang, Wei; Mathias, Patrick C; Cunningham, Brian T

    2010-03-26

    Using a one-dimensional grating surface photonic crystal (PC), we experimentally demonstrate that the detection of fluorescent molecules on a PC surface can be substantially magnified through the combined effects of resonance-enhanced excitation of the fluorescent dye, resonance-enhanced extraction of the fluorescence emission and a dielectric nanorod surface coating increasing the surface area available for fluorophore-PC interaction. Enhanced excitation is obtained by engineering a high-Q TM resonant mode to efficiently couple with an incident TM-polarized lambda = 633 nm laser for exciting Cyanine-5 (Cy5). Enhanced extraction results from a low-Q TE resonance designed to spectrally overlap the Cy5 emission spectrum for channeling TE-polarized emission towards the detection instrument. The entire PC surface is coated with a porous film of TiO(2) nanorods that allows more fluorophores to penetrate into the region of enhanced near-electric fields. Experimental results reveal a 588-fold enhancement in fluorescence intensity relative to an unpatterned glass surface. PMID:20195016

  15. Extraction of Electromagnetic Transition Form Factors for Nucleon Resonances within a Dynamical Coupled-Channels Model

    SciTech Connect

    N. Suzuki, T. Sato, T.-S. H. Lee

    2010-10-01

    We explain the application of a recently developed analytic continuation method to extract the electromagnetic transition form factors for the nucleon resonances ($N^*$) within a dynamical coupled-channel model of meson-baryon reactions.Illustrative results of the obtained $N^*\\rightarrow \\gamma N$ transition form factors, defined at the resonance pole positions on the complex energy plane, for the well isolated $P_{33}$ and $D_{13}$, and the complicated $P_{11}$ resonances are presented. A formula has been developed to give an unified representation of the effects due to the first two $P_{11}$ poles, which are near the $\\pi\\Delta$ threshold, but are on different Riemann sheets. We also find that a simple formula, with its parameters determined in the Laurent expansions of $\\pi N \\rightarrow \\pi N$ and $\\gamma N \\rightarrow\\pi N$ amplitudes, can reproduce to a very large extent the exact solutions of the considered model at energies near the real parts of the extracted resonance positions. We indicate the differences between our results and those extracted from the approaches using the Breit-Wigner parametrization of resonant amplitudes to fit the data.

  16. Extracting robust features from cardiac magnetic resonance image contours for detecting dilated cardiomyopathy

    Microsoft Academic Search

    A. Mueller; N. Merkle; V. Hombach; O. Grebe; T. Nusser; J. Woehrle; L. Binner; H. A. Kestler

    2004-01-01

    Aim of this study was to extract robust features from cine magnetic resonance images (MRI) for phase estimation in dilated cardiomyopathy (DCM) patients. The found features may serve as additional diagnostic parameters. Previously found markers could be improved and were applied to an enlarged subject group. Four quantitative features based on the phase deviation between the left and the right

  17. Energy extraction of Porro resonator in Pockels cell Q-switch operation

    Microsoft Academic Search

    Junewen Chen; Peir-Jyh Wang; Hon-Fai Yau; Sie-Poon Chang

    1996-01-01

    Deviation of a practical Pockels cell Q-switch bias voltage from the ideal bias value significantly affects the extraction of useful output energy. The losses of two practical bias voltages are calculated and the properly rotated angle towards the right-hand side prism of the Porro resonator is determined to simulate the different losses. The losses are due to deviation of the

  18. The Need for Polarization for Extracting Baryon Resonances and the NSTAR Program at CLAS

    SciTech Connect

    Cole, Philip L. [Idaho State University, Dept. of Physics, Pocatello, Idaho 83209 (United States)

    2007-10-26

    We report on the NSTAR program in Hall B of JLab on using polarization observables to extract parameters of baryon resonances. The scientific purpose of the program is to improve the understanding of the underlying quark degrees of freedom, especially in the higher resonance regions, where we expect to uncover many of missing baryon resonances that mainly decay through multi-meson channels. With the high-quality beam of circularly- and linearly-polarized photons onto unpolarized and polarized proton and deteurium targets, and coupled with the nearly complete solid angle coverage of CLAS, we will extract the differential cross sections and associated polarization observables obtained by the photoproduction of vector mesons and kaons at center of mass energies of 1.7 to 2.2 GeV. The paper will primarily present the photon beam aspects of the excited baryon program.

  19. The Need for Polarization for Extracting Baryon Resonances and the NSTAR Program at CLAS

    SciTech Connect

    P.L. Cole

    2007-10-01

    We report on the NSTAR program in Hall B of JLab on using polarization observables to extract parameters of baryon resonances. The scientific purpose of the program is to improve the understanding of the underlying quark degrees of freedom, especially in the higher resonance regions, where we expect to uncover many of missing baryon resonances that mainly decay through multi-meson channels. With the high-quality beam of circularly- and linearly-polarized photons onto unpolarized and polarized proton and deteurium targets, and coupled with the nearly complete solid angle coverage of CLAS, we will extract the differential cross sections and associated polarization observables obtained by the photoproduction of vector mesons and kaons at center of mass energies of 1.7 to 2.2 GeV. The paper will primarily present the photon beam aspects of the excited baryon program.

  20. Extraction of electromagnetic transition form factors for nucleon resonances within a dynamical coupled-channels model

    SciTech Connect

    Suzuki, N.; Sato, T. [Department of Physics, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Excited Baryon Analysis Center (EBAC), Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Lee, T.-S. H. [Excited Baryon Analysis Center (EBAC), Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2010-10-15

    We explain the application of a recently developed analytic continuation method to extract the electromagnetic transition form factors for the nucleon resonances (N*) within a dynamical coupled-channel model of meson-baryon reactions. Illustrative results of the obtained N{sup *{yields}{gamma}}N transition form factors, defined at the resonance pole positions on the complex energy plane, for the well-isolated P{sub 33} and D{sub 13} and the complicated P{sub 11} resonances are presented. A formula was developed to give a unified representation of the effects due to the first two P{sub 11} poles, which are near the {pi}{Delta} threshold, but are on different Riemann sheets. We also find that a simple formula, with its parameters determined in the Laurent expansions of the {pi}N{yields}{pi}N and {gamma}N{yields}{pi}N amplitudes, can reproduce to a very large extent the exact solutions of the considered model at energies near the real parts of the extracted resonance positions. We discuss the important differences between our approach, which is consistent with the earlier formulations of resonances, and the phenomenological approaches using the Breit-Wigner parametrization of resonant amplitudes to fit the data.

  1. Multiaperture ion beam extraction from gas-dynamic electron cyclotron resonance source of multicharged ionsa)

    NASA Astrophysics Data System (ADS)

    Sidorov, A.; Dorf, M.; Zorin, V.; Bokhanov, A.; Izotov, I.; Razin, S.; Skalyga, V.; Roßbach, J.; Spädtke, P.; Balabaev, A.

    2008-02-01

    Electron cyclotron resonance ion source with quasi-gas-dynamic regime of plasma confinement (ReGIS), constructed at the Institute of Applied Physics, Russia, provides opportunities for extracting intense and high-brightness multicharged ion beams. Despite the short plasma lifetime in a magnetic trap of a ReGIS, the degree of multiple ionization may be significantly enhanced by the increase in power and frequency of the applied microwave radiation. The present work is focused on studying the intense beam quality of this source by the pepper-pot method. A single beamlet emittance measured by the pepper-pot method was found to be ˜70?mmmrad, and the total extracted beam current obtained at 14kV extraction voltage was ˜25mA. The results of the numerical simulations of ion beam extraction are found to be in good agreement with experimental data.

  2. Multiaperture ion beam extraction from gas-dynamic electron cyclotron resonance source of multicharged ions.

    PubMed

    Sidorov, A; Dorf, M; Zorin, V; Bokhanov, A; Izotov, I; Razin, S; Skalyga, V; Rossbach, J; Spädtke, P; Balabaev, A

    2008-02-01

    Electron cyclotron resonance ion source with quasi-gas-dynamic regime of plasma confinement (ReGIS), constructed at the Institute of Applied Physics, Russia, provides opportunities for extracting intense and high-brightness multicharged ion beams. Despite the short plasma lifetime in a magnetic trap of a ReGIS, the degree of multiple ionization may be significantly enhanced by the increase in power and frequency of the applied microwave radiation. The present work is focused on studying the intense beam quality of this source by the pepper-pot method. A single beamlet emittance measured by the pepper-pot method was found to be approximately 70 pi mm mrad, and the total extracted beam current obtained at 14 kV extraction voltage was approximately 25 mA. The results of the numerical simulations of ion beam extraction are found to be in good agreement with experimental data. PMID:18315107

  3. Multiaperture ion beam extraction from gas-dynamic electron cyclotron resonance source of multicharged ions

    SciTech Connect

    Sidorov, A.; Dorf, M.; Zorin, V.; Bokhanov, A.; Izotov, I.; Razin, S.; Skalyga, V.; Rossbach, J.; Spaedtke, P.; Balabaev, A. [Institute of Applied Physics, RAS, 46 Ulyanov St., 603950 Nizhny Novgorod (Russian Federation); Gesellschaft fur Schwerionenforschung (GSI), Planckstr. 1, 64291 Darmstadt (Germany); Institute for Theoretical and Experimental Physics, 25 B. Cheremushkinskaya St., 117259 Moscow (Russian Federation)

    2008-02-15

    Electron cyclotron resonance ion source with quasi-gas-dynamic regime of plasma confinement (ReGIS), constructed at the Institute of Applied Physics, Russia, provides opportunities for extracting intense and high-brightness multicharged ion beams. Despite the short plasma lifetime in a magnetic trap of a ReGIS, the degree of multiple ionization may be significantly enhanced by the increase in power and frequency of the applied microwave radiation. The present work is focused on studying the intense beam quality of this source by the pepper-pot method. A single beamlet emittance measured by the pepper-pot method was found to be {approx}70 {pi} mm mrad, and the total extracted beam current obtained at 14 kV extraction voltage was {approx}25 mA. The results of the numerical simulations of ion beam extraction are found to be in good agreement with experimental data.

  4. Resonance extractions in the {alpha}+{sup 8}He slow scattering

    SciTech Connect

    Ito, Makoto [Pure and Applied Physics, Kansai University, Yamate-cho 3-3-35, Suita 564-8680 (Japan); Research Center for Nuclear Physics (RCNP), Osaka University, Mihogaoka 10-1, Suita 567-0047 (Japan); RIKEN Nishina Center for Accelerator-based Science, RIKEN, Wako, 351-0198, Saitama (Japan); Suzuki, Daisuke [National Superconducting Cyclotron Laboratory, Michigan State University, 1 Cyclotron, East Lansing, Michigan 48824-1321 (United States)

    2011-07-15

    The {alpha}+{sup 8}He low-energy reactions and the exotic structures of {sup 12}Be={alpha}+{alpha}+4N are studied by the application of the generalized two-center cluster model. In the two-neutron transfer reactions, {alpha}+{sup 8}He{sub g.s.}{yields}{sup 6}He{sub g.s.}+{sup 6}He{sub g.s.}, resonant structures with a sharp width of {Gamma}<1 MeV appear in the central collision (J{sup {pi}=}0{sup +}). The reaction mechanism is analyzed, and we confirmed that the transfer coupling plays essential roles in the resonance formation with sharp width. Angular distributions for the scattered {sup 6}He are analyzed to extract resonant structures for individual partial waves. We found that, for the low-spin resonances, the angular selection around 90 deg. in the center-of-mass system, which is usually employed in the high-spin resonances of light-ion systems, is not necessarily appropriate to separate the resonance contribution with a definite spin. The validity of the selection angle around 90 deg. is discussed in the higher partial waves.

  5. Extraction of $P_{11}$ Resonance from piN Data and Its Stability

    SciTech Connect

    Satoshi Nakamura

    2011-10-01

    We address a question about how much resonance poles and residues extracted from data depend on a model used for the extraction, and on the precision of data. We focus on the P{sub 11} {pi}-N scattering and use the dynamical coupled-channel (DCC) model developed in Excited Baryon Analysis Center (EBAC) at JLab. We examine the model-dependence of the poles by varying parameters largely within the EBAC-DCC model. We find that two poles associated with the Roper resonance are fairly stable against the variation. We also study the stability of the Roper poles against different analytic structure of the P{sub 11} amplitude below {pi}-N threshold by using a bare nucleon model. We again find a good stability of the Roper poles.

  6. Multiaperture ion beam extraction from gas-dynamic electron cyclotron resonance source of multicharged ions

    Microsoft Academic Search

    A. Sidorov; M. Dorf; V. Zorin; A. Bokhanov; I. Izotov; S. Razin; V. Skalyga; J. Rossbach; P. Spaedtke; A. Balabaev

    2008-01-01

    Electron cyclotron resonance ion source with quasi-gas-dynamic regime of plasma confinement (ReGIS), constructed at the Institute of Applied Physics, Russia, provides opportunities for extracting intense and high-brightness multicharged ion beams. Despite the short plasma lifetime in a magnetic trap of a ReGIS, the degree of multiple ionization may be significantly enhanced by the increase in power and frequency of the

  7. Measurement of Optical Response of a Detuned Resonant Sideband Extraction Interferometer

    E-print Network

    Miyakawa, O; Adhikari, R; Evans, M; Abbott, B; Bork, R; Busby, D; Heefner, J; Ivanov, A; Smith, M; Taylor, R; Vass, S; Weinstein, A; Varvella, M; Kawamura, S; Kawazoe, F; Sakata, S; Mow-Lowry, C; Miyakawa, Osamu; Ward, Robert; Adhikari, Rana; Evans, Matthew; Abbott, Benjamin; Bork, Rolf; Busby, Daniel; Heefner, Jay; Ivanov, Alexander; Smith, Michael; Taylor, Robert; Vass, Stephen; Weinstein, Alan; Varvella, Monica; Kawamura, Seiji; Kawazoe, Fumiko; Sakata, Shihori; Mow-Lowry, Conor

    2006-01-01

    We report on the optical response of a suspended-mass detuned resonant sideband extraction (RSE) interferometer with power recycling. The purpose of the detuned RSE configuration is to manipulate and optimize the optical response of the interferometer to differential displacements (induced by gravitational waves) as a function of frequency, independently of other parameters of the interferometer. The design of our interferometer results in an optical gain with two peaks: an RSE optical resonance at around 4 kHz and a radiation pressure induced optical spring at around 41 Hz. We have developed a reliable procedure for acquiring lock and establishing the desired optical configuration. In this configuration, we have measured the optical response to differential displacement and found good agreement with predictions at both resonances and all other relevant frequencies. These results build confidence in both the theory and practical implementation of the more complex optical configuration being planned for Advanc...

  8. A simple method for extracting material parameters of multilayered MEMS structures using resonance frequency measurements

    NASA Astrophysics Data System (ADS)

    Sun, Chao; Zhou, Zai-Fa; Li, Wei-Hua; Huang, Qing-An

    2014-07-01

    Multilayered structures are increasingly used in MEMS. Based on the resonant frequency of the doubly-clamped multilayered beam, the Young’s modulus and residual stress for an individual layer have been measured by designing beam test structures for each layer with different widths. Taking into account the buckling or no buckling problem of the multilayered beam, this paper introduces a model for the resonant frequency of the beam. An approach to extract the Young’s modulus and residual stress for the individual layer is developed. The validity of this approach has been studied using finite element modeling. As a multilayered example, test structures for a gold/polysilicon bilayer beam were fabricated. A scanning laser Doppler vibrometer system was used to measure the resonant frequency of the beam. The extracted parameters are that the average value of Young’s modulus of polysilicon and gold are 133.7?GPa and 78.6?GPa with standard deviation being 4.2?GPa and 11.5?GPa, respectively; the average value of residual stress of polysilicon and gold are 13.9?MPa (compressive) and 19.7?MPa (tensile) with standard deviation being 0.47?MPa and 4.4?MPa, respectively.

  9. Electron cyclotron resonance 140 mA D(+) beam extraction optimization for IFMIF EVEDA accelerator.

    PubMed

    Delferrière, O; De Menezes, D; Gobin, R; Harrault, F; Tuske, O

    2008-02-01

    Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120 mA H(+) beam, the CEA-Saclay is in charge of the design and realization of the 140 mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of two accelerators of 125 mA D(+) beam at 40 MeV that hit in parallel a lithium target. IFMIF utilizes the deuteron-lithium (d-Li) neutron, producing a reaction to simulate the 14 MeV neutron environment in deuterium-tritium (D-T) fusion reactors. In the framework of the IFMIF EVEDA phase (Engineering Validation and Engineering Design Activities), we are studying a cw ECR ion source with a new extraction system to allow high current extraction while keeping a low divergence as well as a small emittance. Starting from SILHI five-electrode system with H(+) ions, the extracted beam characteristics as well as electric field conditions are compared with the cases of four- and three-electrode extraction systems. Experimental results made on the SILHI source with H(+) ions are briefly discussed. Extensive experimental results on the new source test bench BETSI are expected as soon as the design and fabrication of a dedicated extraction system with a new set of electrodes will be finished. PMID:18315214

  10. Electron cyclotron resonance 140mA D+ beam extraction optimization for IFMIF EVEDA acceleratora)

    NASA Astrophysics Data System (ADS)

    Delferrière, O.; De Menezes, D.; Gobin, R.; Harrault, F.; Tuske, O.

    2008-02-01

    Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120mA H+ beam, the CEA-Saclay is in charge of the design and realization of the 140mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of two accelerators of 125mA D+ beam at 40MeV that hit in parallel a lithium target. IFMIF utilizes the deuteron-lithium (d-Li) neutron, producing a reaction to simulate the 14MeV neutron environment in deuterium-tritium (D-T) fusion reactors. In the framework of the IFMIF EVEDA phase (Engineering Validation and Engineering Design Activities), we are studying a cw ECR ion source with a new extraction system to allow high current extraction while keeping a low divergence as well as a small emittance. Starting from SILHI five-electrode system with H+ ions, the extracted beam characteristics as well as electric field conditions are compared with the cases of four- and three-electrode extraction systems. Experimental results made on the SILHI source with H+ ions are briefly discussed. Extensive experimental results on the new source test bench BETSI are expected as soon as the design and fabrication of a dedicated extraction system with a new set of electrodes will be finished.

  11. Polarizability extraction for rapid computation of Fano resonance in nanoring lattices

    NASA Astrophysics Data System (ADS)

    Forcherio, Gregory T.; DeJarnette, Drew; Blake, Phillip; Roper, D. Keith

    2014-09-01

    Rapid modeling of far-field Fano resonance supported by lattices of complex nanostructures is possible with the coupled dipole approximation (CDA) using point, dipole polarizability extrapolated from a higher order discrete dipole approximation (DDA). Fano resonance in nanostructured metamaterials has been evaluated with CDA for spheroids, for which an analytical form of particle polarizability exists. For complex structures with non-analytic polarizability, such as rings, higher order electrodynamic solutions must be employed at the cost of computation time. Point polarizability is determined from the DDA by summing individual polarizable volume elements from the modeled structure. Extraction of single nanoring polarizability from DDA permitted CDA analysis of nanoring lattices with a 40,000-fold reduction in computational time over 1000 wavelengths. Maxima and minima of predicted Fano resonance energies were within 1% of full volume elements using the DDA. This modeling technique is amenable to other complex nanostructures which exhibit primarily dipolar and/or quadrupolar resonance behavior. Rapid analysis of coupling between plasmons and photon diffraction modes in lattices of nanostructures supports design of plasmonic enhancements in sustainable energy and biomedical devices.

  12. Extracting Information about the Rotator Cuff from Magnetic Resonance Images Using Deterministic and Random Techniques

    PubMed Central

    De Los Ríos, F. A.; Paluszny, M.

    2015-01-01

    We consider some methods to extract information about the rotator cuff based on magnetic resonance images; the study aims to define an alternative method of display that might facilitate the detection of partial tears in the supraspinatus tendon. Specifically, we are going to use families of ellipsoidal triangular patches to cover the humerus head near the affected area. These patches are going to be textured and displayed with the information of the magnetic resonance images using the trilinear interpolation technique. For the generation of points to texture each patch, we propose a new method that guarantees the uniform distribution of its points using a random statistical method. Its computational cost, defined as the average computing time to generate a fixed number of points, is significantly lower as compared with deterministic and other standard statistical techniques. PMID:25650281

  13. An Analysis Method for Superconducting Resonator Parameter Extraction with Complex Baseline Removal

    NASA Technical Reports Server (NTRS)

    Cataldo, Giuseppe

    2014-01-01

    A new semi-empirical model is proposed for extracting the quality (Q) factors of arrays of superconducting microwave kinetic inductance detectors (MKIDs). The determination of the total internal and coupling Q factors enables the computation of the loss in the superconducting transmission lines. The method used allows the simultaneous analysis of multiple interacting discrete resonators with the presence of a complex spectral baseline arising from reflections in the system. The baseline removal allows an unbiased estimate of the device response as measured in a cryogenic instrumentation setting.

  14. Extracting Phase and Amplitude Modifications of Laser-Coupled Fano Resonances

    NASA Astrophysics Data System (ADS)

    Kaldun, Andreas; Ott, Christian; Blättermann, Alexander; Laux, Martin; Meyer, Kristina; Ding, Thomas; Fischer, Andreas; Pfeifer, Thomas

    2014-03-01

    Fano line shapes observed in absorption spectra encode information on the amplitude and phase of the optical dipole response. A change in the Fano line shape, e.g., by interaction with short-pulsed laser fields, allows us to extract dynamical modifications of the amplitude and phase of the coupled excited quantum states. We introduce and apply this physical mechanism to near-resonantly coupled doubly excited states in helium. This general approach provides a physical understanding of the laser-induced spectral shift of absorption-line maxima on a sub-laser-cycle time scale as they are ubiquitously observed in attosecond transient-absorption measurements.

  15. Progress towards the development of a realistic electron cyclotron resonance ion source extraction model.

    PubMed

    Winklehner, D; Leitner, D; Benitez, J Y; Lyneis, C M; Strohmeier, M M

    2012-02-01

    In this paper, an ongoing effort to provide a simulation and design tool for electron cyclotron resonance ion source extraction and low energy beam transport is described and benchmarked against experimental results. Utilizing the particle-in-cell code WARP, a set of scripts has been developed: A semiempirical method of generating initial conditions, a 2D-3D hybrid method of plasma extraction and a simple beam transport deck. Measured emittances and beam profiles of uranium and helium beams are shown and the influence of the sextupole part of the plasma confinement field is investigated. The results are compared to simulations carried out using the methods described above. The results show that the simulation model (with some additional refinements) represents highly charged, well-confined ions well, but that the model is less applicable for less confined, singly charged ions. PMID:22380311

  16. Dynamical coupled-channels model of $K^- p$ reactions (II): Extraction of $\\Lambda^*$ and $\\Sigma^*$ hyperon resonances

    E-print Network

    Kamano, H; Lee, T -S H; Sato, T

    2015-01-01

    Resonance parameters (pole masses and residues) associated with the excited states of hyperons, Lambda^* and Sigma^*, are extracted within a dynamical coupled-channels model developed recently in Phys. Rev. C 90, 065204 (2014) through a comprehensive partial-wave analysis of the K^- p --> barK N, pi Sigma, pi Lambda, eta Lambda, K Xi data up to invariant mass W = 2.1 GeV. We confirm the existence of resonances corresponding to most, if not all, of the four-star resonances rated by the Particle Data Group. We also find several new resonances, and in particular propose a possible existence of a new narrow J^P=3/2^+ Lambda resonance that couples strongly to the eta Lambda channel. The J^P=1/2^- Lambda resonances located below the barK N threshold are also discussed. Comparing our extracted pole masses with the ones from a recent analysis by the Kent State University group, some significant differences in the extracted resonance parameters are found, suggesting the need of more extensive and accurate data of K^- ...

  17. Investigations on the structure of the extracted ion beam from an electron cyclotron resonance ion source

    SciTech Connect

    Spaedtke, P.; Lang, R.; Maeder, J.; Rossbach, J.; Tinschert, K. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Maimone, F. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Universita degli Studi di Catania, D.M.F.C.I, Viale A. Doria 6, 95125 Catania (Italy)

    2012-02-15

    Using improved beam diagnostic tools, the structure of an ion beam extracted from an electron cyclotron resonance ion source (ECRIS) becomes visible. Especially viewing targets to display the beam profile and pepper pot devices for emittance measurements turned out to be very useful. On the contrary, diagnostic tools integrating over one space coordinate like wire harps for profile measurements or slit-slit devices, respectively slit-grid devices to measure the emittance might be applicable for beam transport investigations in a quadrupole channel, but are not very meaningful for investigations regarding the given ECRIS symmetry. Here we try to reproduce the experimentally found structure on the ion beam by simulation. For the simulation, a certain model has to be used to reproduce the experimental results. The model is also described in this paper.

  18. Investigations on the structure of the extracted ion beam from an electron cyclotron resonance ion sourcea)

    NASA Astrophysics Data System (ADS)

    Spädtke, P.; Lang, R.; Mäder, J.; Maimone, F.; Roßbach, J.; Tinschert, K.

    2012-02-01

    Using improved beam diagnostic tools, the structure of an ion beam extracted from an electron cyclotron resonance ion source (ECRIS) becomes visible. Especially viewing targets to display the beam profile and pepper pot devices for emittance measurements turned out to be very useful. On the contrary, diagnostic tools integrating over one space coordinate like wire harps for profile measurements or slit-slit devices, respectively slit-grid devices to measure the emittance might be applicable for beam transport investigations in a quadrupole channel, but are not very meaningful for investigations regarding the given ECRIS symmetry. Here we try to reproduce the experimentally found structure on the ion beam by simulation. For the simulation, a certain model has to be used to reproduce the experimental results. The model is also described in this paper.

  19. Investigations on the structure of the extracted ion beam from an electron cyclotron resonance ion source.

    PubMed

    Spädtke, P; Lang, R; Mäder, J; Maimone, F; Rossbach, J; Tinschert, K

    2012-02-01

    Using improved beam diagnostic tools, the structure of an ion beam extracted from an electron cyclotron resonance ion source (ECRIS) becomes visible. Especially viewing targets to display the beam profile and pepper pot devices for emittance measurements turned out to be very useful. On the contrary, diagnostic tools integrating over one space coordinate like wire harps for profile measurements or slit-slit devices, respectively slit-grid devices to measure the emittance might be applicable for beam transport investigations in a quadrupole channel, but are not very meaningful for investigations regarding the given ECRIS symmetry. Here we try to reproduce the experimentally found structure on the ion beam by simulation. For the simulation, a certain model has to be used to reproduce the experimental results. The model is also described in this paper. PMID:22380325

  20. Beam size versus intensity for resonant extracted beam at the Brookhaven AGS

    SciTech Connect

    Brown, K.A.; Thern, R. [Brookhaven National Lab., Upton, NY (United States); Huang, H. [Indiana Univ., (United States)

    1995-05-01

    Transverse beam sizes were measured in the AGS prior to the initiation of the third order resonance ({nu}{sub H} = 8 2/3; driven by sextupoles) used for the slow extraction and again in the external beam lines. The measurements were made using the AGS Ionization Profile Monitor (IPM) and an External Profile Monitor (EPM). Both of these monitors use the ionized residual gas to image the beam on arrays of wires that are aligned parallel to the direction of the beam. The effects of space charge on the IPM are significant at the intensities measured, but the EPM measurements are not affected by space charge. Two measurements are reported. First is the intensity dependence of the resonant beam size, and secondly, an indirect measure of the space charge effect on the IPM. A differential comparison of the two monitors in the vertical plane allows unfolding the effect of the space charge on the measurements. These measurements were made over an intensity range between 15 {times} 10{sup 12} and 36 {times} 10{sup 12} protons per AGS pulse.

  1. Plasma potential and energy spread determination using ion beams extracted from an electron cyclotron resonance source

    SciTech Connect

    Harris, P. R.; Meyer, F. W. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6372 (United States)

    2010-02-15

    We have obtained estimates of plasma potentials and energy spreads characterizing an electron cyclotron resonance ion source plasma under different source conditions. Our estimates are obtained from analysis of ion beams extracted from the ion source at 10 kV that are subsequently decelerated into a floating surface scattering chamber where their current intensity incident on a solid sample is measured as function of retardation voltage. The deceleration occurs outside the measurement chamber, permitting beam current measurements in a field-free region. Absence of grids in the deceleration section avoids potential issues of field penetration. The behavior of our deceleration optics was modeled with SIMION. The simulation indicated a linear beam attenuation dependence close to full retardation where the beam current goes to zero. Deviations from this linear dependence observed close to zero beam energy give information on the initial energy spread of the ions extracted from the source. Our decelerated beams measurements are compared with recent in situ probe results and external beams results based on magnetic analysis.

  2. Adaptive bistable stochastic resonance and its application in mechanical fault feature extraction

    NASA Astrophysics Data System (ADS)

    Qin, Yi; Tao, Yi; He, Ye; Tang, Baoping

    2014-12-01

    Stochastic resonance (SR) is an important approach to detect weak vibration signals from heavy background noise. In order to increase the calculation speed and improve the weak feature detection performance, a new bistable model has been built. With this model, an adaptive and fast SR method based on dyadic wavelet transform and least square system parameters solving is proposed in this paper. By adding the second-order differential item into the traditional bistable model, noise utilization can be increased and the quality of SR output signal can be improved. The iteration algorithm for implementing the adaptive SR is given. Compared with the traditional adaptive SR method, this algorithm does not need to set up the searching range and searching step size of the system parameters, but only requires a few iterations. The proposed method, discrete wavelet transform and the traditional adaptive SR method are applied to analyzing simulated vibration signals and extracting the fault feature of a rotor system. The contrastive results verify the superiority of the proposed method, and it can be effectively applied to weak mechanical fault feature extraction.

  3. Extracting S-matrix poles for resonances from numerical scattering data: Type-II Padé reconstruction

    NASA Astrophysics Data System (ADS)

    Sokolovski, D.; Akhmatskaya, E.; Sen, S. K.

    2011-02-01

    We present a FORTRAN 77 code for evaluation of resonance pole positions and residues of a numerical scattering matrix element in the complex energy (CE) as well as in the complex angular momentum (CAM) planes. Analytical continuation of the S-matrix element is performed by constructing a type-II Padé approximant from given physical values (Bessis et al. (1994) [42]; Vrinceanu et al. (2000) [24]; Sokolovski and Msezane (2004) [23]). The algorithm involves iterative 'preconditioning' of the numerical data by extracting its rapidly oscillating potential phase component. The code has the capability of adding non-analytical noise to the numerical data in order to select 'true' physical poles, investigate their stability and evaluate the accuracy of the reconstruction. It has an option of employing multiple-precision (MPFUN) package (Bailey (1993) [45]) developed by D.H. Bailey wherever double precision calculations fail due to a large number of input partial waves (energies) involved. The code has been successfully tested on several models, as well as the F + H 2 ? HF + H, F + HD ? HF + D, Cl + HCl ? ClH + Cl and H + D 2 ? HD + D reactions. Some detailed examples are given in the text. Program summaryProgram title: PADE II Catalogue identifier: AEHO_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHO_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 19 959 No. of bytes in distributed program, including test data, etc.: 158 380 Distribution format: tar.gz Programming language: FORTRAN 77 Computer: Any computer equipped with a FORTRAN 90 compiler Operating system: UNIX, LINUX RAM: 256 Mb Classification: 16.8 External routines: NAG Program Library ( http://www.nag.co.uk/numeric/fl/FLdescription.asp) Nature of problem: The package extracts the positions and residues of resonance poles from numerical scattering data supplied by the user. The data can then be used for quantitative analysis of interference patterns observed in elastic, inelastic and reactive integral and differential cross sections. Solution method: The S-matrix element is analytically continued in the complex plane of either energy or angular momentum with the help of Padé approximation of type II. Resonance (complex energy or Regge) poles are identified and their residues evaluated. Unusual features: Use of multiple precision MPFUN package (Bailey (1993) [45]). (Distributed with the PADE II code.) Running time: From several seconds to several minutes depending on the precision level chosen and the number of iterations performed.

  4. Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source.

    PubMed

    Roychowdhury, P; Mishra, L; Kewlani, H; Patil, D S; Mittal, K C

    2014-03-01

    A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20-40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, -2 to -4 kV, and 0 kV, respectively. The total ion beam current of 30-40 mA is recorded on Faraday cup at 40 keV of beam energy at 600-1000 W of microwave power, 800-1000 G axial magnetic field and (1.2-3.9) × 10(-3) mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source. PMID:24689571

  5. Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source

    SciTech Connect

    Roychowdhury, P., E-mail: pradipr@barc.gov.in; Mishra, L.; Kewlani, H.; Mittal, K. C. [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)] [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Patil, D. S. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)] [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2014-03-15

    A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20–40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, ?2 to ?4 kV, and 0 kV, respectively. The total ion beam current of 30–40 mA is recorded on Faraday cup at 40 keV of beam energy at 600–1000 W of microwave power, 800–1000 G axial magnetic field and (1.2–3.9) × 10{sup ?3} mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source.

  6. Sample preparation of Mycobacterium tuberculosis extracts for nuclear magnetic resonance metabolomic studies.

    PubMed

    Zinniel, Denise K; Fenton, Robert J; Halouska, Steven; Powers, Robert; Barletta, Raul G

    2012-01-01

    Mycobacterium tuberculosis is a major cause of mortality in human beings on a global scale. The emergence of both multi- (MDR) and extensively-(XDR) drug-resistant strains threatens to derail current disease control efforts. Thus, there is an urgent need to develop drugs and vaccines that are more effective than those currently available. The genome of M. tuberculosis has been known for more than 10 years, yet there are important gaps in our knowledge of gene function and essentiality. Many studies have since used gene expression analysis at both the transcriptomic and proteomic levels to determine the effects of drugs, oxidants, and growth conditions on the global patterns of gene expression. Ultimately, the final response of these changes is reflected in the metabolic composition of the bacterium including a few thousand small molecular weight chemicals. Comparing the metabolic profiles of wild type and mutant strains, either untreated or treated with a particular drug, can effectively allow target identification and may lead to the development of novel inhibitors with anti-tubercular activity. Likewise, the effects of two or more conditions on the metabolome can also be assessed. Nuclear magnetic resonance (NMR) is a powerful technology that is used to identify and quantify metabolic intermediates. In this protocol, procedures for the preparation of M. tuberculosis cell extracts for NMR metabolomic analysis are described. Cell cultures are grown under appropriate conditions and required Biosafety Level 3 containment, harvested, and subjected to mechanical lysis while maintaining cold temperatures to maximize preservation of metabolites. Cell lysates are recovered, filtered sterilized, and stored at ultra-low temperatures. Aliquots from these cell extracts are plated on Middlebrook 7H9 agar for colony-forming units to verify absence of viable cells. Upon two months of incubation at 37 °C, if no viable colonies are observed, samples are removed from the containment facility for downstream processing. Extracts are lyophilized, resuspended in deuterated buffer and injected in the NMR instrument, capturing spectroscopic data that is then subjected to statistical analysis. The procedures described can be applied for both one-dimensional (1D) H NMR and two-dimensional (2D) H-(13)C NMR analyses. This methodology provides more reliable small molecular weight metabolite identification and more reliable and sensitive quantitative analyses of cell extract metabolic compositions than chromatographic methods. Variations of the procedure described following the cell lysis step can also be adapted for parallel proteomic analysis. PMID:22971839

  7. Resonance Raman Spectroscopy of Single-Wall Carbon Nanotubes Separated via Aqueous Two-Phase Extraction

    NASA Astrophysics Data System (ADS)

    Simpson, J. R.; Fagan, J. A.; Hight Walker, A. R.

    2014-03-01

    We report Resonance Raman Spectroscopy (RRS) measurements of single-wall carbon nanotube (SWCNT) samples dispersed in aqueous solutions via surfactant wrapping and separated using aqueous two-phase extraction (ATPE) into chirality-enriched semiconducting and metallic SWCNT species. ATPE provides a rapid, robust, and remarkably tunable separation technique that allows isolation of high-purity, individual SWCNT chiralities via modification of the surfactant environment. We report RRS measurements of individual SWCNT species of various chiral index including, armchair and zigzag metals. Raman provides a powerful technique to quantify the metallic SWCNTs in ATPE fractions separated for metallicity. We measure Raman spectra over a wide range of excitation wavelengths from 457 nm to 850 nm using a series of discrete and continuously tunable laser sources coupled to a triple-grating spectrometer with a liquid-nitrogen-cooled detector. The spectra reveal Raman-active vibrational modes, including the low-frequency radial breathing mode (RBM) and higher-order modes. SWCNT chiral vectors are determined from the Raman spectra, specifically the RBM frequencies and corresponding energy excitation profiles, together with input from theoretical models.

  8. Annular-coupled concave-convex stable resonator for large-volume high-quality energy extraction.

    PubMed

    Cheng, Z; Seguin, H J; Nikumb, S K; Seguin, V A; Reshef, H

    1988-03-01

    A theoretical investigation of a stable concave-convex resonator configuration, which appears suitable for single-mode high-power energy extraction from large volume gain media, is presented. The design features annular output coupling with a surprisingly uniform near-field intensity distribution. The computer-based analysis, supported by preliminary experimental results, suggests that acceptable alignment tolerances are provided along with an unusually small beam divergence. With proper design, a far-field divergence of 0.5 mrad, encompassing near 80% of the total laser energy, appears feasible. Operational data, recently obtained with this optical extraction approach, have revealed a further important practical advantage over an unstable resonator, being far less prone to mode degradation and hot spot formation on optical component misalignment. PMID:20523697

  9. Detection of trinitrotoluene (TNT) extracted from soil using a surface plasmon resonance (SPR)-based sensor platform

    NASA Astrophysics Data System (ADS)

    Strong, Anita A.; Stimpson, Donald I.; Bartholomew, Dwight U.; Jenkins, Thomas F.; Elkind, Jerome L.

    1999-08-01

    An antibody-based competition assay has been developed using a surface plasmon resonance (SPR) sensor platform for the detection of trinitrotoluene (TNT) in soil extract solutions. The objective of this work is to develop a sensor-based assay technology to use in the field for real- time detection of land mines. This immunoassay combines very simple bio-film attachment procedures and a low-cost SPR sensor design to detect TNT in soil extracts. The active bio-surface is a coating of bovine serum albumin that has been decorated with trinitrobenzene groups. A blind study on extracts from a large soil matrix was recently performed and result from this study will be presented. Potential interferant studied included 2,4-dinitrophenol, 2,4- dinitrotoluene, ammonium nitrate, and 2,4- dichlorophenoxyacetic acid. Cross-reactivity with dinitrotoluene will be discussed. Also, plans to reach sensitivity levels of 1ppb TNT in soil will be described.

  10. Electron cyclotron resonance 140 mA D{sup +} beam extraction optimization for IFMIF EVEDA accelerator

    SciTech Connect

    Delferriere, O.; De Menezes, D.; Gobin, R.; Harrault, F.; Tuske, O. [Commissariat a l'Energie Atomique (CEA)-Saclay, DSM/DAPNIA, 91191 Gif sur Yvette Cedex (France)

    2008-02-15

    Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120 mA H{sup +} beam, the CEA-Saclay is in charge of the design and realization of the 140 mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of two accelerators of 125 mA D{sup +} beam at 40 MeV that hit in parallel a lithium target. IFMIF utilizes the deuteron-lithium (d-Li) neutron, producing a reaction to simulate the 14 MeV neutron environment in deuterium-tritium (D-T) fusion reactors. In the framework of the IFMIF EVEDA phase (Engineering Validation and Engineering Design Activities), we are studying a cw ECR ion source with a new extraction system to allow high current extraction while keeping a low divergence as well as a small emittance. Starting from SILHI five-electrode system with H{sup +} ions, the extracted beam characteristics as well as electric field conditions are compared with the cases of four- and three-electrode extraction systems. Experimental results made on the SILHI source with H{sup +} ions are briefly discussed. Extensive experimental results on the new source test bench BETSI are expected as soon as the design and fabrication of a dedicated extraction system with a new set of electrodes will be finished.

  11. Resonance

    NSDL National Science Digital Library

    Kuphaldt, Tony R.

    All About Circuits is a website that â??provides a series of online textbooks covering electricity and electronics.â? Written by Tony R. Kuphaldt, the textbooks available here are wonderful resources for students, teachers, and anyone who is interested in learning more about electronics. This specific section, Resonance, is the sixth chapter in the Volume II textbook. Topics covered in this chapter include: electric pendulum, simple parallel resonance, simple series resonance, resonance in series-parallel circuits, and Q and bandwidth of a resonant circuit. Diagrams and detailed descriptions of concepts are included throughout the chapter to provide users with a comprehensive lesson. Visitors to the site are also encouraged to discuss concepts and topics using the All About Circuits discussion forums (registration with the site is required to post materials).

  12. Spatially resolved charge-state and current-density distributions at the extraction of an electron cyclotron resonance ion source.

    PubMed

    Panitzsch, Lauri; Peleikis, Thies; Stalder, Michael; Wimmer-Schweingruber, Robert F

    2011-09-01

    In this paper we present our measurements of charge-state and current-density distributions performed in very close vicinity (15 mm) of the extraction of our hexapole geometry electron cyclotron resonance ion source. We achieved a relatively high spatial resolution reducing the aperture of our 3D-movable extraction (puller) electrode to a diameter of only 0.5 mm. Thus, we are able to limit the source of the extracted ion beam to a very small region of the plasma electrode's hole (Ø = 4 mm) and therefore to a very small region of the neutral plasma sheath. The information about the charge-state distribution and the current density in the plane of the plasma electrode at each particular position is conserved in the ion beam. We determined the total current density distribution at a fixed coaxial distance of only 15 mm to the plasma electrode by remotely moving the small-aperture puller electrode which contained a dedicated Faraday cup (FC) across the aperture of the plasma electrode. In a second measurement we removed the FC and recorded m/q-spectra for the different positions using a sector magnet. From our results we can deduce that different ion charge-states can be grouped into bloated triangles of different sizes and same orientation at the extraction with the current density peaking at centre. This confirms observations from other groups based on simulations and emittance measurements. We present our measurements in detail and discuss possible systematic errors. PMID:21974580

  13. Spatially resolved charge-state and current-density distributions at the extraction of an electron cyclotron resonance ion source

    SciTech Connect

    Panitzsch, Lauri; Peleikis, Thies; Stalder, Michael; Wimmer-Schweingruber, Robert F. [Institute for Experimental and Applied Physics (IEAP), Christian-Albrechts-Universitaet, Kiel (Germany)

    2011-09-15

    In this paper we present our measurements of charge-state and current-density distributions performed in very close vicinity (15 mm) of the extraction of our hexapole geometry electron cyclotron resonance ion source. We achieved a relatively high spatial resolution reducing the aperture of our 3D-movable extraction (puller) electrode to a diameter of only 0.5 mm. Thus, we are able to limit the source of the extracted ion beam to a very small region of the plasma electrode's hole (O = 4 mm) and therefore to a very small region of the neutral plasma sheath. The information about the charge-state distribution and the current density in the plane of the plasma electrode at each particular position is conserved in the ion beam. We determined the total current density distribution at a fixed coaxial distance of only 15 mm to the plasma electrode by remotely moving the small-aperture puller electrode which contained a dedicated Faraday cup (FC) across the aperture of the plasma electrode. In a second measurement we removed the FC and recorded m/q-spectra for the different positions using a sector magnet. From our results we can deduce that different ion charge-states can be grouped into bloated triangles of different sizes and same orientation at the extraction with the current density peaking at centre. This confirms observations from other groups based on simulations and emittance measurements. We present our measurements in detail and discuss possible systematic errors.

  14. Automatic Mapping Extraction from Multiecho T2-Star Weighted Magnetic Resonance Images for Improving Morphological Evaluations in Human Brain

    PubMed Central

    Yu, Shaode; Xie, Yaoqin

    2013-01-01

    Mapping extraction is useful in medical image analysis. Similarity coefficient mapping (SCM) replaced signal response to time course in tissue similarity mapping with signal response to TE changes in multiecho T2-star weighted magnetic resonance imaging without contrast agent. Since different tissues are with different sensitivities to reference signals, a new algorithm is proposed by adding a sensitivity index to SCM. It generates two mappings. One measures relative signal strength (SSM) and the other depicts fluctuation magnitude (FMM). Meanwhile, the new method is adaptive to generate a proper reference signal by maximizing the sum of contrast index (CI) from SSM and FMM without manual delineation. Based on four groups of images from multiecho T2-star weighted magnetic resonance imaging, the capacity of SSM and FMM in enhancing image contrast and morphological evaluation is validated. Average contrast improvement index (CII) of SSM is 1.57, 1.38, 1.34, and 1.41. Average CII of FMM is 2.42, 2.30, 2.24, and 2.35. Visual analysis of regions of interest demonstrates that SSM and FMM show better morphological structures than original images, T2-star mapping and SCM. These extracted mappings can be further applied in information fusion, signal investigation, and tissue segmentation. PMID:24379892

  15. Automatic bone segmentation and bone-cartilage interface extraction for the shoulder joint from magnetic resonance images.

    PubMed

    Yang, Zhengyi; Fripp, Jurgen; Chandra, Shekhar S; Neubert, Aleš; Xia, Ying; Strudwick, Mark; Paproki, Anthony; Engstrom, Craig; Crozier, Stuart

    2015-02-21

    We present a statistical shape model approach for automated segmentation of the proximal humerus and scapula with subsequent bone-cartilage interface (BCI) extraction from 3D magnetic resonance (MR) images of the shoulder region. Manual and automated bone segmentations from shoulder MR examinations from 25 healthy subjects acquired using steady-state free precession sequences were compared with the Dice similarity coefficient (DSC). The mean DSC scores between the manual and automated segmentations of the humerus and scapula bone volumes surrounding the BCI region were 0.926? ± ?0.050 and 0.837? ± ?0.059, respectively. The mean DSC values obtained for BCI extraction were 0.806? ± ?0.133 for the humerus and 0.795? ± ?0.117 for the scapula. The current model-based approach successfully provided automated bone segmentation and BCI extraction from MR images of the shoulder. In future work, this framework appears to provide a promising avenue for automated segmentation and quantitative analysis of cartilage in the glenohumeral joint. PMID:25611124

  16. Extracting meson-baryon contributions to the electroexcitation of the N(1675)52- nucleon resonance

    DOE PAGESBeta

    Aznauryan, Inna G.; Burkert, Volker D.

    2015-07-01

    We report on the determination of the electrocouplings for the transition from the proton to the $N(1675){\\frac{5}{2}}^-$ resonance state using recent differential cross section data on $e p \\rightarrow e\\pi^+ n$ by the CLAS collaboration at $1.8 \\le Q^2 more »contributions at $Q^2 \\geq 1.8 $GeV$^2$ from the dynamical coupled-channel model.« less

  17. Electron cyclotron resonance 140 mA D+ beam extraction optimization for IFMIF EVEDA accelerator

    Microsoft Academic Search

    O. Delferrière; D. de Menezes; R. Gobin; F. Harrault; O. Tuske

    2008-01-01

    Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120 mA H+ beam, the CEA-Saclay is in charge of the design and realization of the 140 mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of two

  18. Influence of frequency tuning and double-frequency heating on ions extracted from an electron cyclotron resonance ion source

    SciTech Connect

    Maimone, F. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Universita degli Studi di Catania, D.M.F.C.I,Viale A. Doria 6, 95125 Catania (Italy); Celona, L. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Lang, R.; Maeder, J.; Rossbach, J.; Spaedtke, P.; Tinschert, K. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany)

    2011-12-15

    The electromagnetic field within the plasma chamber of an electron cyclotron resonance ion source (ECRIS) and the properties of the plasma waves affect the plasma properties and ion beam production. We have experimentally investigated the ''frequency tuning effect'' and ''double frequency heating'' on the CAPRICE ECRIS device. A traveling wave tube amplifier, two microwave sweep generators, and a dedicated experimental set-up were used to carry out experiments in the 12.5-16.5 GHz frequency range. During the frequency sweeps the evolution of the intensity and shape of the extracted argon beam were measured together with the microwave reflection coefficient. A range of different ion source parameter settings was used. Here we describe these experiments and the resultant improved understanding of these operational modes of the ECR ion source.

  19. Note: resonant microwave compressor with two output ports for synchronous energy extraction.

    PubMed

    Avgustinovich, V A; Artemenko, S N; Kaminsky, V L; Novikov, S A; Yushkov, Yu G

    2011-04-01

    The brief theoretical analysis shows the resonant microwave compressor provides the output pulse power higher than the traveling wave power in the storage cavity. The experimental study was made with the model of the S-band microwave compressor. The power of pulses generated by the device reached the value three times as much as the value of the traveling wave power in the storage cavity at the maximum amplification 23 dB, peak power 400 MW, and pulse width 4-5 ns. PMID:21529048

  20. Results of Nucleon Resonance Extraction via Dynamical Coupled-Channels Analysis from Collaboration@EBAC

    E-print Network

    Hiroyuki Kamano

    2012-06-15

    We review a global analysis of meson production reactions off the nucleons by a collaboration at Excited Baryon Analysis Center of Jefferson Lab. The analysis is pursued with a dynamical coupled-channels approach, within which the dynamics of multi-channel reaction processes are taken into account in a fully consistent way with the two-body as well as three-body unitarity of the S-matrix. With this approach, new features of nucleon excitations are revealed as resonant particles originating from the non-trivial multi-channel reaction dynamics, which cannot be addressed by static hadron models where the nucleon excitations are treated as stable particles.

  1. Results of Nucleon Resonance Extraction via Dynamical Coupled-Channels Analysis from #11;Collaboration @ EBAC

    SciTech Connect

    Hiroyuki Kamano

    2012-04-01

    We review a global analysis of meson production reactions off the nucleons by a collaboration at Excited Baryon Analysis Center of Jefferson Lab. The analysis is pursued with a dynamical coupled-channels approach, within which the dynamics of multi-channel reaction processes are taken into account in a fully consistent way with the two-body as well as three-body unitarity of the S-matrix. With this approach, new features of nucleon excitations are revealed as resonant particles originating from the non-trivial multi-channel reaction dynamics, which cannot be addressed by static hadron models where the nucleon excitations are treated as stable particles.

  2. Sequential application of viscous opening and lower leveling for three-dimensional brain extraction on magnetic resonance imaging T1

    NASA Astrophysics Data System (ADS)

    Mendiola-Santibañez, Jorge Domingo; Gallegos-Duarte, Martín; Arias-Estrada, Miguel Octavio; Santillán-Méndez, Israel Marcos; Rodríguez-Reséndiz, Juvenal; Terol-Villalobos, Iván Ramón

    2014-05-01

    A composition of the viscous opening and the lower leveling is introduced to extract brain in magnetic resonance imaging T1. The innovative transformation disconnects chained components and has better control on the reconstruction process of the marker inside of the original image. However, the sequential operator requires setting several parameters, making its application difficult. Due to this situation, a simplification is carried out on it to obtain a more practical method. The proposed morphological transformations were tested with the Internet Brain Segmentation Repository (IBSR) database, which is used as a benchmark among the community. The results are compared using the Jaccard and Dice indices with respect to (i) manual segmentations obtained from the IBSR, (ii) mean indices reported in the current literature, and (iii) segmentations obtained from the Brain Extraction Tool, since this is one of the most popular algorithms used for brain segmentation. The average indices of Jaccard and Dice indicate that the reduced transformation produces similar results to the other methods reported in the literature while the sequential operator presents a better performance.

  3. Automated Feature Extraction in Brain Tumor by Magnetic Resonance Imaging Using Gaussian Mixture Models

    PubMed Central

    Chaddad, Ahmad

    2015-01-01

    This paper presents a novel method for Glioblastoma (GBM) feature extraction based on Gaussian mixture model (GMM) features using MRI. We addressed the task of the new features to identify GBM using T1 and T2 weighted images (T1-WI, T2-WI) and Fluid-Attenuated Inversion Recovery (FLAIR) MR images. A pathologic area was detected using multithresholding segmentation with morphological operations of MR images. Multiclassifier techniques were considered to evaluate the performance of the feature based scheme in terms of its capability to discriminate GBM and normal tissue. GMM features demonstrated the best performance by the comparative study using principal component analysis (PCA) and wavelet based features. For the T1-WI, the accuracy performance was 97.05% (AUC = 92.73%) with 0.00% missed detection and 2.95% false alarm. In the T2-WI, the same accuracy (97.05%, AUC = 91.70%) value was achieved with 2.95% missed detection and 0.00% false alarm. In FLAIR mode the accuracy decreased to 94.11% (AUC = 95.85%) with 0.00% missed detection and 5.89% false alarm. These experimental results are promising to enhance the characteristics of heterogeneity and hence early treatment of GBM. PMID:26136774

  4. Highly efficient, dynamically stable Nd?:?YAG single-rod resonators with 60% TEM00 extraction efficiency and high misalignment stability

    NASA Astrophysics Data System (ADS)

    Pinto, R. S.; Wetter, N. U.

    2014-08-01

    We systematically investigate positive and negative slope resonators with joint stability zones and show the advantages and drawbacks of the different designs. As a result we achieve more than 60% fundamental mode extraction efficiency in Nd?:?YAG with regard to multimode output, without using any compensation for thermally induced bifocusing or birefringence. For fully polarized output, we obtain more than 53% extraction efficiency in fundamental mode. To our knowledge, these efficiencies are the highest so far reported for single-rod and double-rod diode pumped solid-state laser.

  5. A UV resonance Raman (UVRR) spectroscopic study on the extractable compounds of Scots pine ( Pinus sylvestris) wood . Part I: Lipophilic compounds

    NASA Astrophysics Data System (ADS)

    Nuopponen, M.; Willför, S.; Jääskeläinen, A.-S.; Sundberg, A.; Vuorinen, T.

    2004-11-01

    The wood resin in Scots pine ( Pinus sylvestris) stemwood and branch wood were studied using UV resonance Raman (UVRR) spectroscopy. UVRR spectra of the sapwood and heartwood hexane extracts, solid wood samples and model compounds (six resin acids, three fatty acids, a fatty acid ester, sitosterol and sitosterol acetate) were collected using excitation wavelengths of 229, 244 and 257 nm. In addition, visible Raman spectra of the fatty and resin acids were recorded. Resin compositions of heartwood and sapwood hexane extracts were determined using gas chromatography. Raman signals of both conjugated and isolated double bonds of all the model compounds were resonance enhanced by UV excitation. The oleophilic structures showed strong bands in the region of 1660-1630 cm -1. Distinct structures were enhanced depending on the excitation wavelength. The UVRR spectra of the hexane extracts showed characteristic bands for resin and fatty acids. It was possible to identify certain resin acids from the spectra. UV Raman spectra collected from the solid wood samples containing wood resin showed a band at ˜1650 cm -1 due to unsaturated resin components. The Raman signals from extractives in the resin rich branch wood sample gave even more strongly enhanced signals than the aromatic lignin.

  6. Studies of extraction and transport system for highly charged ion beam of 18 GHz superconducting electron cyclotron resonance ion source at Research Center for Nuclear Physics.

    PubMed

    Yorita, T; Hatanaka, K; Fukuda, M; Ueda, H; Yasuda, Y; Morinobu, S; Tamii, A; Kamakura, K

    2014-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source is installed to increase beam currents and to extend the variety of ions especially for highly charged heavy ions which can be accelerated by cyclotrons of Research Center for Nuclear Physics (RCNP), Osaka University. The beam production developments of several ions from B to Xe have been already done [T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 79, 02A311 (2008) and T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 81, 02A332 (2010)] and the further studies for those beam extraction and its transport have been done in order to increase the beam current more. The plasma electrode, extraction electrode, and einzel lens are modified. Especially extraction electrode can be applied minus voltage for the beam extraction and it works well to improve the extracted beam current. The extraction voltage dependences of transmission and emittance also have been studied for beam current improvement which is injected into azimuthally varying field cyclotron at RCNP. PMID:24593475

  7. Direct assessment by electron spin resonance spectroscopy of the antioxidant effects of French maritime pine bark extract in the maxillofacial region of hairless mice.

    PubMed

    Yoshida, Ayaka; Yoshino, Fumihiko; Tsubata, Masahito; Ikeguchi, Motoya; Nakamura, Takeshi; Lee, Masaichi-Chang-Il

    2011-09-01

    Flavangenol, one of extract of French maritime pine bark, is a complex mixture of bioflavonoids with oligometric proanthocyanidins as the major constituents. These constituents, catechin and procyanidin B(1), are water-soluble derivatives of flavangenol. In this study, we investigated the antioxidant effects of flavangenol on reactive oxygen species such as hydroxyl radical, superoxide anion and singlet oxygen using electron spin resonance and spin trapping. The effect of flavangenol on oxidative stress in the skin from the maxillofacial region of hairless mice was investigated using an in vivo L-band electron spin resonance imaging system. Flavangenol attenuated oxidative stress in the maxillofacial skin by acting as a reactive oxygen species scavenger, as demonstrated by in vitro and in vivo electron spin resonance imaging analysis. The absorption and metabolism of flavangenol were also examined. After oral administration of flavangenol in human and rat, most of the catechin in plasma was in the conjugated form, while 45% to 78% of procyanidin B(1) was unconjugated, indicating that non-conjugated procyanidin B(1) would be active in the circulation. The ability of flavangenol to reduce reactive oxygen species levels in the circulation of the maxillofacial region suggests that this extract may be beneficial for skin protection from exposure to ultraviolet irradiation. PMID:21980222

  8. Direct assessment by electron spin resonance spectroscopy of the antioxidant effects of French maritime pine bark extract in the maxillofacial region of hairless mice

    PubMed Central

    Yoshida, Ayaka; Yoshino, Fumihiko; Tsubata, Masahito; Ikeguchi, Motoya; Nakamura, Takeshi; Lee, Masaichi-Chang-il

    2011-01-01

    Flavangenol, one of extract of French maritime pine bark, is a complex mixture of bioflavonoids with oligometric proanthocyanidins as the major constituents. These constituents, catechin and procyanidin B1, are water-soluble derivatives of flavangenol. In this study, we investigated the antioxidant effects of flavangenol on reactive oxygen species such as hydroxyl radical, superoxide anion and singlet oxygen using electron spin resonance and spin trapping. The effect of flavangenol on oxidative stress in the skin from the maxillofacial region of hairless mice was investigated using an in vivo L-band electron spin resonance imaging system. Flavangenol attenuated oxidative stress in the maxillofacial skin by acting as a reactive oxygen species scavenger, as demonstrated by in vitro and in vivo electron spin resonance imaging analysis. The absorption and metabolism of flavangenol were also examined. After oral administration of flavangenol in human and rat, most of the catechin in plasma was in the conjugated form, while 45% to 78% of procyanidin B1 was unconjugated, indicating that non-conjugated procyanidin B1 would be active in the circulation. The ability of flavangenol to reduce reactive oxygen species levels in the circulation of the maxillofacial region suggests that this extract may be beneficial for skin protection from exposure to ultraviolet irradiation. PMID:21980222

  9. Combined use of high-resolution ?-glucosidase inhibition profiling and high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy for investigation of antidiabetic principles in crude plant extracts.

    PubMed

    Kongstad, Kenneth T; Özdemir, Ceylan; Barzak, Asmah; Wubshet, Sileshi G; Staerk, Dan

    2015-03-01

    Type 2 diabetes is a metabolic disorder affecting millions of people worldwide, and new drug leads or functional foods containing selective ?-glucosidase inhibitors are needed. Crude extract of 24 plants were assessed for ?-glucosidase inhibitory activity. Methanol extracts of Cinnamomum zeylanicum bark, Rheum rhabarbarum peel, and Rheum palmatum root and ethyl acetate extracts of C. zeylanicum bark, Allium ascalonicum peel, and R. palmatum root showed IC50 values below 20 ?g/mL. Subsequently, high-resolution ?-glucosidase profiling was used in combination with high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy for identification of metabolites responsible for the ?-glucosidase inhibitory activity. Quercetin (1) and its dimer (2), trimer (3), and tetramer (4) were identified as main ?-glucosidase inhibitors in A. ascalonicum peel, whereas (E)-piceatannol 3'-O-?-D-glucopyranoside (5), (E)-rhapontigenin 3'-O-?-D-glucopyranoside (6), (E)-piceatannol (8), and emodin (12) were identified as main ?-glucosidase inhibitors in R. palmatum root. PMID:25652946

  10. Performance of a 4 GeV/c magnetic spectrograph taking advantage of the third integral resonant extraction properties to operate in the energy loss mode

    NASA Astrophysics Data System (ADS)

    Grorud, E.; Laclare, JL.; Ropert, A.; Tkatchenko, A.; Banaigs, J.; Boivin, M.

    SPES 4, a magnetic spectrograph, has been designed at Saturne National Laboratory for high energy particle identification (up to about 4 GeV/ c) with a momentum resolution of about 5 × 10 -4. Dipole magnets have been made from the old synchroton yokes. It is possible to compensate for the energy dispersion of the incident beam by taking advantage of the third integral resonant extraction properties. Resolution power has been recently tested by analysing the spectrum of 1.04 GeV protons scattered by a 12C target. Results are in good agreement with calculations made with a ray-tracing program using the measured field maps of the magnets.

  11. pH recycling aqueous two-phase systems applied in extraction of Maitake ?-Glucan and mechanism analysis using low-field nuclear magnetic resonance.

    PubMed

    Hou, Huiyun; Cao, Xuejun

    2015-07-31

    In this paper, a recycling aqueous two-phase systems (ATPS) based on two pH-response copolymers PADB and PMDM were used in purification of ?-Glucan from Grifola frondosa. The main parameters, such as polymer concentration, type and concentration of salt, extraction temperature and pH, were investigated to optimize partition conditions. The results demonstrated that ?-Glucan was extracted into PADB-rich phase, while impurities were extracted into PMDM-rich phase. In this 2.5% PADB/2.5% PMDM ATPS, 7.489 partition coefficient and 96.92% extraction recovery for ?-Glucan were obtained in the presence of 30mmol/L KBr, at pH 8.20, 30°C. The phase-forming copolymers could be recycled by adjusting pH, with recoveries of over 96.0%. Furthermore, the partition mechanism of Maitake ?-Glucan in PADB/PMDM aqueous two-phase systems was studied. Fourier transform infrared spectra, ForteBio Octet system and low-field nuclear magnetic resonance (LF-NMR) were introduced for elucidating the partition mechanism of ?-Glucan. Especially, LF-NMR was firstly used in the mechanism analysis in partition of aqueous two-phase systems. The change of transverse relaxation time (T2) in ATPS could reflect the interaction between polymers and ?-Glucan. PMID:26094138

  12. Determination of phosphate compounds in meat products by 31Phosphorus Nuclear Magnetic Resonance spectroscopy with methylenediphosphonic acid after alkaline extraction

    Microsoft Academic Search

    P. Hrynczyszyn; A. Jastrz?bska; E. Sz?yk

    2010-01-01

    Modification of the extraction procedure and application of the 31P NMR method for the determination of polyphosphates in meat products were studied. In the elaborated procedure threefold water extraction at alkaline pH (borate buffer and 0.1M EDTA) was applied. Furthermore, the new external standard for 31P NMR determination of phosphates was proposed. Obtained recoveries were between 95 and 99% and

  13. Simultaneous molecular formula determinations of natural compounds in a plant extract using 15 T Fourier transform ion cyclotron resonance mass spectrometry

    PubMed Central

    2013-01-01

    Background Plant extracts are a reservoir of pharmacologically active substances; however, conventional analytical methods can analyze only a small portion of an extract. Here, we report a high-throughput analytical method capable of determining most phytochemicals in a plant extract and of providing their molecular formulae from a single experiment using ultra-high-resolution electrospray ionization mass spectrometry (UHR ESI MS). UHR mass profiling was used to analyze natural compounds in a 70% ethanol ginseng extract, which was directly infused into a 15 T Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer for less than 10 min without a separation process. Results The UHR FT-ICR MS yielded a mass accuracy of 0.5 ppm and a mass resolving power (m/?m) of 1,000,000–270,000 for the range m/z 290–1,100. The mass resolution was sufficient to resolve the isotopic fine structure (IFS) of many compounds in the extract. After noise removal from 1,552 peaks, 405 compounds were detected. The molecular formulae of 123 compounds, including 33 ginsenosides, were determined using the observed IFS, exact monoisotopic mass, and exact mass difference. Liquid chromatography (LC)/FT-ICR MS of the extract was performed to compare the high-throughput performance of UHR ESI FT-ICR MS. The LC/FT-ICR MS detected only 129 compounds, including 19 ginsenosides. The result showed that UHR ESI FT-ICR MS identified three times more compounds than LC/FT-ICR MS and in a relatively shorter time. The molecular formula determination by UHR FT-ICR MS was validated by LC and tandem MS analyses of three known ginsenosides. Conclusions UHR mass profiling of a plant extract by 15 T FT-ICR MS showed that multiple compounds were simultaneously detected and their molecular formulae were decisively determined by a single experiment with ultra-high mass resolution and mass accuracy. Simultaneous molecular determination of multiple natural products by UHR ESI FT-ICR MS would be a powerful method to profile a wide range of natural compounds. PMID:23721581

  14. The influence of the extraction voltage on the energetic electron population of an electron cyclotron resonance ion source plasma

    SciTech Connect

    Stiebing, K. E. [Institut fuer Kernphysik der J. W. Goethe-Universitaet, Frankfurt/Main (Germany); Schaechter, L.; Dobrescu, S. [National Institute for Physics and Nuclear Engineering, Bucharest (Romania)

    2012-02-15

    An influence of the extraction voltage on the high energy slope of bremsstrahlung radiation spectra has been reported in ECRIS experiments, which is not well understood so far. In order to provide more detailed data on this effect, we have measured bremsstrahlung radiation spectra accompanying especially the evolution of highly charge ions (i.e., by monitoring the Ar{sup 14+} charge state) as the extraction voltage is changed from 0 to 20 kV, in dedicated experiments at the Frankfurt 14 GHz-ECRIS.

  15. Dynamic analysis of torsional resonance mode of atomic force microscopy and its application to in-plane surface property extraction

    Microsoft Academic Search

    Yaxin Song; Bharat Bhushan

    2006-01-01

    In the torsional resonance (TR) mode of atomic force microscopy (AFM), the changes in the torsion-related dynamic characteristics\\u000a of a tip–cantilever system due to in-plane (lateral) tip–sample interaction are used for surface property imaging. This paper\\u000a investigates the fundamental dynamics of a tip–cantilever system when it is operated in TR mode, with or without tip–sample\\u000a interaction. With the actual location

  16. Electron cyclotron resonance 140 mA D{sup +} beam extraction optimization for IFMIF EVEDA accelerator

    Microsoft Academic Search

    O. Delferriere; D. De Menezes; R. Gobin; F. Harrault; O. Tuske

    2008-01-01

    Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120 mA H{sup +} beam, the CEA-Saclay is in charge of the design and realization of the 140 mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of

  17. Experimental investigation of a control scheme for a zero-detuning resonant sideband extraction interferometer for next-generation gravitational-wave detectors

    E-print Network

    Kawazoe, Fumiko; Kawamura, Seiji; Leonhardt, Volker; Miyakawa, Osamu; Morioka, Tomoko; Nishizawa, Atsushi; Sato, Shuichi; Somiya, Kentaro; Sugamoto, Akio; Yamazaki, Toshitaka

    2008-01-01

    Some next-generation gravitational-wave detectors, such as the American Advanced LIGO project and the Japanese LCGT project, plan to use power recycled resonant sideband extraction (RSE) interferometers for their interferometer's optical configuration. A power recycled zero-detuning (PRZD) RSE interferometer, which is the default design for LCGT, has five main length degrees of freedom that need to be controlled in order to operate a gravitational-wave detector. This task is expected to be very challenging because of the complexity of optical configuration. A new control scheme for a PRZD RSE interferometer has been developed and tested with a prototype interferometer. The PRZD RSE interferometer was successfully locked with the control scheme. It is the first experimental demonstration of a PRZD RSE interferometer with suspended test masses. The result serves as an important step for the operation of LCGT.

  18. Experimental investigation of a control scheme for a zero-detuning resonant sideband extraction interferometer for next-generation gravitational-wave detectors

    E-print Network

    Fumiko Kawazoe; Mitsuhiro Fukushima; Seiji Kawamura; Volker Leonhardt; Osamu Miyakawa; Tomoko Morioka; Atsushi Nishizawa; Shuichi Sato; Kentaro Somiya; Akio Sugamoto; Toshitaka Yamazaki

    2008-04-25

    Some next-generation gravitational-wave detectors, such as the American Advanced LIGO project and the Japanese LCGT project, plan to use power recycled resonant sideband extraction (RSE) interferometers for their interferometer's optical configuration. A power recycled zero-detuning (PRZD) RSE interferometer, which is the default design for LCGT, has five main length degrees of freedom that need to be controlled in order to operate a gravitational-wave detector. This task is expected to be very challenging because of the complexity of optical configuration. A new control scheme for a PRZD RSE interferometer has been developed and tested with a prototype interferometer. The PRZD RSE interferometer was successfully locked with the control scheme. It is the first experimental demonstration of a PRZD RSE interferometer with suspended test masses. The result serves as an important step for the operation of LCGT.

  19. Determination of phosphate compounds in meat products by 31-phosphorus nuclear magnetic resonance spectroscopy with methylenediphosphonic acid after alkaline extraction.

    PubMed

    Hrynczyszyn, P; Jastrzebska, A; Sz?yk, E

    2010-07-12

    Modification of the extraction procedure and application of the (31)P NMR method for the determination of polyphosphates in meat products were studied. In the elaborated procedure threefold water extraction at alkaline pH (borate buffer and 0.1 M EDTA) was applied. Furthermore, the new external standard for (31)P NMR determination of phosphates was proposed. Obtained recoveries were between 95 and 99% and variation coefficients (CV) was < or = 5%, indicating an increase in accuracy and the precision of the proposed procedure in relation to the spectrophotometric method. The described procedure of sample preparation with (31)P NMR method was applied for the determination of polyphosphate additives in meat products. The satisfactory precision (CV=0.39-3.40%) shows the benefit of the NMR method in the routine analysis of the phosphate ions in meat products. PMID:20630180

  20. Measurements of $ep \\to e^\\prime ?^+n$ at W = 1.6 - 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS

    DOE PAGESBeta

    Park, Kijun; et. al.,; Aznauryan, I. G.; Burkert, V. D.; Adhikari, K. P.; Amaryan, M. J.; Pereira, S. Anefalos; Avakian, H.; Battaglieri, M.; Badui, R.; et al

    2015-04-01

    Differential cross sections of the exclusive process $e p \\to e^\\prime \\pi^+ n$ were measured with good precision in the range of the photon virtuality $Q^2 = 1.8 - 4.5$ GeV$^2$, and the invariant mass range of the $\\pi^+ n$ final state W = 1.6 - 2.0 GeV using the CEBAF Large Acceptance Spectrometer. Data were collected with nearly complete coverage in the azimuthal and polar angles of the $n\\pi^+$ center-of-mass system. More than 37,000 cross section points were measured. The contributions of the isospin $I = {1\\over 2}$ resonances $N(1675){5\\over 2}^-$, $N(1680){5\\over 2}^+$ and $N(1710){1\\over 2}^+$ were extracted atmore »different values of $Q^2$ using a single-channel, energy-dependent resonance amplitude analysis. Two different approaches, the unitary isobar model and the fixed-$t$ dispersion relations, were employed in the analysis. We observe significant strength of the $N(1675){5\\over 2}^-$ in the $A_{1/2}$ amplitude, which is in strong disagreement with quark models that predict both transverse amplitudes to be strongly suppressed. For the $N(1680){5\\over 2}^+$ we observe a slow changeover from the dominance of the $A_{3/2}$ amplitude at the real photon point ($Q^2=0$) to a $Q^2$ where $A_{1/2}$ begins to dominate. The scalar amplitude $S_{1/2}$ drops rapidly with $Q^2$ consistent with quark model prediction. For the $N(1710){1\\over 2}^+$ resonance our analysis shows significant strength for the $A_{1/2}$ amplitude at $Q^2 « less

  1. Measurements of $ep \\to e^\\prime ?^+n$ at W = 1.6 - 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS

    DOE PAGESBeta

    Park, Kijun [ODU, JLAB; et. al.,; Aznauryan, I. G.; Burkert, V. D.; Adhikari, K. P.; Amaryan, M. J.; Pereira, S. Anefalos; Avakian, H.; Battaglieri, M.; Badui, R.; Bedlinskiy, I.; Biselli, A. S.; Bono, J.; Briscoe, W. J.; Brooks, W. K.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; Alaoui, A. El; Elouadrhiri, L.; Fassi, L. El; Eugenio, P.; Fedotov, G.; Fegan, S.; Fersch, R.; Filippi, A.; Fleming, J. A.; Garillon, B.; Gar??on, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Joo, H.S.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guo, L.; Hakobyan, H.; Hanretty, C.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J.; Markov, N.; Martinez, D.; McKinnon, B.; Mokeev, V.; Montgomery, R. A.; Moutarde, H.; Camacho, C. Munoz; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Pasyuk, E.; Peng, P.; Phelps, W.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabati??, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, Iu.; Smith, E. S.; Smith, G. D.; Sparveris, N.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tian, Ye; Trivedi, A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2015-04-01

    Differential cross sections of the exclusive process $e p \\to e^\\prime \\pi^+ n$ were measured with good precision in the range of the photon virtuality $Q^2 = 1.8 - 4.5$ GeV$^2$, and the invariant mass range of the $\\pi^+ n$ final state W = 1.6 - 2.0 GeV using the CEBAF Large Acceptance Spectrometer. Data were collected with nearly complete coverage in the azimuthal and polar angles of the $n\\pi^+$ center-of-mass system. More than 37,000 cross section points were measured. The contributions of the isospin $I = {1\\over 2}$ resonances $N(1675){5\\over 2}^-$, $N(1680){5\\over 2}^+$ and $N(1710){1\\over 2}^+$ were extracted at different values of $Q^2$ using a single-channel, energy-dependent resonance amplitude analysis. Two different approaches, the unitary isobar model and the fixed-$t$ dispersion relations, were employed in the analysis. We observe significant strength of the $N(1675){5\\over 2}^-$ in the $A_{1/2}$ amplitude, which is in strong disagreement with quark models that predict both transverse amplitudes to be strongly suppressed. For the $N(1680){5\\over 2}^+$ we observe a slow changeover from the dominance of the $A_{3/2}$ amplitude at the real photon point ($Q^2=0$) to a $Q^2$ where $A_{1/2}$ begins to dominate. The scalar amplitude $S_{1/2}$ drops rapidly with $Q^2$ consistent with quark model prediction. For the $N(1710){1\\over 2}^+$ resonance our analysis shows significant strength for the $A_{1/2}$ amplitude at $Q^2 < 2.5$ GeV$^2$.

  2. Resonant and nonresonant charge exchange and extraction. Progress report IV, 1 December 1982-30 November 1983

    SciTech Connect

    Shafroth, S.M.

    1983-01-01

    From an experimental point of view we were very much encouraged by two three day runs at TUNL, one in April and one in July, where we studied Resonant Transfer and Excitation (RTE) and Non-resonant Transfer and Excitation (NTE), via the x-ray charge changed coincidence method. The projectile was Si/sup 11 +/. Target gases of He, Ne, and Ar were used under single collision conditions. This was ensured by taking all data at four different pressures including zero, and verifying the linear dependence of count rate on pressure. In all cases, Si K..cap alpha.. and K..beta.. x rays were observed in coincidence with Si/sup 10 +/ and Si/sup 12 +/, and for Ne and Ar coincidences were also observed with Si/sup 9 +/ and Si/sup 13 +/. In the case of Ar target gas the Ar K..cap alpha.. and K..beta.. x rays were clearly observed in coincidence with single and double electron capture and loss. In the two TUNL runs we obtained a large amount of data: (1) Single and double electron capture and loss cross sections for the three gases; (2) Si K..cap alpha.. and Si K..beta.. x-ray yield curves from 20 to 85 MeV for the three gases; (3) Ar K..cap alpha.., K..beta.. and possibly Ne K x ray yield curves over the entire energy range; (4) All x rays are in coincidence with single electron capture and loss. In the case of Ar and Ne there are a significant number of coincidences between projectiles which have gained two electrons and projectile K x rays.

  3. Plasma Potential and Energy Spread Determination Using Ion Beams Extracted from an Electron Cyclotron Resonance (ECR) Source

    SciTech Connect

    Harris, Peter R [ORNL; Meyer, Fred W [ORNL

    2010-01-01

    We have obtained estimates of plasma potentials and energy spreads characterizing an ECR ion source plasma under different source conditions. Our estimates are obtained from analysis of ion beams extracted from the ion source at 10 kV that are subsequently decelerated into a floating surface scattering chamber where their current intensity incident on a solid sample is measured as function of retardation voltage. The deceleration occurs outside the measurement chamber, permitting beam current measurements in a field-free region. Absence of grids in the deceleration section avoids potential issues of field penetration. The behavior of our deceleration optics was modeled with SIMION. The simulation indicated a linear beam attenuation dependence close to full retardation where the beam current goes to zero. Deviations from this linear dependence observed close to zero beam energy give information on the initial energy spread of the ions extracted from the source. Our decelerated beams measurements are compared with recent in-situ probe results and external beams results based on magnetic analysis.

  4. Modeling relationships among active components in black raspberry (Rubus occidentalis L.) fruit extracts using high-resolution (1)H nuclear magnetic resonance (NMR) spectroscopy and multivariate statistical analysis.

    PubMed

    Wyzgoski, Faith J; Paudel, Liladhar; Rinaldi, Peter L; Reese, R Neil; Ozgen, Mustafa; Tulio, Artemio Z; Miller, A Raymond; Scheerens, Joseph C; Hardy, James K

    2010-03-24

    A process was developed to ascertain the bioactive components of black raspberry (Rubus occidentalis L.) fruit extracts by relating chemical constituents determined by high-field nuclear magnetic resonance (NMR) spectroscopy to biological responses using partial least-squares regression analysis. To validate our approach, we outlined relationships between phenolic signals in NMR spectra and chemical data for total monomeric anthocyanin (TMA) content and antioxidant capacity by the ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Anthocyanins, cyanidin 3-O-rutinoside (Cy 3-rut), cyanidin 3-O-(2(G))-xylosylrutinoside (Cy 3-xylrut), and cyanidin 3-O-glucoside (Cy 3-glc), were significant contributors to the variability in assay results, with the two most important NMR bins corresponding to the methyl peaks in Cy 3-rut (6''') and/or Cy 3-xylrut (6(IV)). Many statistically important bins were common among assay models, but differences in structure-activity relationships resulted in changes in bin ranking. The specificity of these results supported the application of the process to investigate relationships among health-beneficial natural products and potential biological activity. PMID:20192269

  5. Direct proof by 13C-nuclear magnetic resonance of semi-purified extract and isolation of ent-Catechin from leaves of Eucalyptus cinerea

    PubMed Central

    Silva, Sayonara Mendes; Abe, Simone Yae; Bueno, Fernanda Giacomini; Lopes, Norberto Peporine; de Mello, João Carlos Palazzo; Nakashima, Tomoe

    2014-01-01

    Background: Eucalyptus cinerea F. Muell. ex Benth. is native to Australia and acclimatized to Southern Brazil. Its aromatic leaves are used for ornamental purposes and have great potential for essential oil production, although reports of its use in folk medicine are few. Objective: This study evaluated the composition of E. cinerea leaves using the solid state 13C-nuclear magnetic resonance (NMR) and isolation of the compound from the semipurified extract (SE). Materials and Methods: The SE of E. cinerea leaves was evaluated in the solid state by 13C-NMR spectrum, and the SE was chromatographed on a Sephadex LH-20 column, followed by high-speed counter-current chromatography to isolate the compound. The SE was analyzed by 13C-NMR and matrix-assisted laser desorption/ionization-time-of-flight spectra. Results: Flavan-3-ol units were present, suggesting the presence of proanthocyanidins as well as a gallic acid unit. The uncommon ent-catechin was isolated. Conclusion: The presence of ent-catechin is reported for the first time in this genus and species. PMID:25210302

  6. Multichannel laser resonators — an experimental study

    Microsoft Academic Search

    E. F. Yelden; H. J. J. Seguin; C. E. Capjack; S. K. Nikumb; H. Reshef

    1992-01-01

    The output characteristics of several large-area multichannel unstable resonators are presented. The conventional unstable resonator and a novel toric unstable resonator, in both confocal and nonconfocal configurations, have been studied. Output beam profiles, optical energy extraction, beam focusability, resonator alignment properties and polarization states of the various resonators have been analysed in depth.

  7. Screening of key antioxidant compounds of longan (Dimocarpus longan Lour.) seed extract by combining online fishing/knockout, activity evaluation, Fourier transform ion cyclotron resonance mass spectrometry, and high-performance liquid chromatography electrospray ionization mass spectrometry methods.

    PubMed

    Chen, Jinyu; Ge, Zhen-Zhen; Zhu, Wei; Xu, Ze; Li, Chun-Mei

    2014-10-01

    To figure out the key phenolic compounds accounting for the antioxidant effects of longan (Dimocarpus longan Lour.) seed extract, online fishing/knockout method, activity evaluation assays, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), and high-performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) analysis were used jointly for the first time. p-Coumaric acid-glycoside, (S)-flavogallonic acid, ellagic acid derivative, and methyl-ellagic acid glucopyranoside were first identified in longan seeds. In addition, our study revealed that ellagic acid as well as its derivative and p-coumaric acid-glycoside had important contribution to the potent antioxidant activity of longan seed extract, while gallic acid, corilagin, (S)-flavogallonic acid, methyl-ellagic acid glucopyranoside, and ethyl gallate showed very little contribution to the total antioxidant activity of longan seed extract. The combining use of the online fishing/knockout method, activity evaluation assays, FT-ICR-MS, and HPLC-ESI-MS analysis is a useful and simple strategy for screening of key bioactive compounds from complex extracts. PMID:25220361

  8. Review of lattice studies of resonances

    E-print Network

    Daniel Mohler

    2012-11-26

    I review recent progress in extracting resonance parameters using lattice field theory, with an emphasis on determining hadron resonances from lattice quantum chromodynamics. Until recently, the \\rho-meson channel was the only one considered, while, during the last year, several resonant channels have been investigated for the first time. Recent lattice results for scattering phase shifts in resonant channels are presented.

  9. Stochastic Resonance

    NASA Astrophysics Data System (ADS)

    McDonnell, Mark D.; Stocks, Nigel G.; Pearce, Charles E. M.; Abbott, Derek

    2012-10-01

    Preface; 1. Introduction and motivation; 2. Stochastic resonance: its definitions, history and debates; 3. Stochastic quantization; 4. Suprathreshold stochastic resonance: encoding; 5. Suprathreshold stochastic resonance: large N encoding; 6. Suprathreshold stochastic resonance: decoding; 7. Suprathreshold stochastic resonance: large N decoding; 8. Optimal stochastic quantization; 9. SSR, neural coding, and performance tradeoffs; 10. Stochastic resonance in the auditory system; 11. The future of stochastic resonance and suprathreshold stochastic resonance; Appendices; References; Index.

  10. Object extraction Object extraction

    E-print Network

    Giger, Christine

    (is a grass-roof a vegetation area?) · object ontologies are hierarchical (tree / forrest / vegetation · buildings · vegetation · roads #12;Interactive object extraction #12;Interactive object extraction angles in man-made structures · measurement accuracy of human operator is lower than that of automatic

  11. Alkaloid analysis by high-performance liquid chromatography-solid phase extraction-nuclear magnetic resonance: new strategies going beyond the standard.

    PubMed

    Johansen, Kenneth T; Ebild, Sarah J; Christensen, S Brøgger; Godejohann, Markus; Jaroszewski, Jerzy W

    2012-12-28

    The hyphenated technique HPLC-SPE-NMR is an important tool for rapid dereplication of complex mixtures of in particular small molecules and has been successfully employed in natural product research. However, positively charged alkaloids at low pH are often poorly trapped on the generally used SPE cartridge limiting the general application of the procedure. In this work, two new approaches for efficient SPE trapping of alkaloids and elution efficiencies were evaluated using 24 model alkaloids. Use of a 0.1 M NaOH solution as the post-column dilution greatly enhanced trapping of alkaloids on the commonly used cartridge containing divinylbenzene polymer (GP resin). This procedure, however, was unsuitable for trapping phenolic alkaloids. Severe line broadening and immiscibility with water made chloroform-d(1) unsuited as eluent. None of these problems occurred when methanol-d(4) was used as eluent. Previously, mixed mode cation exchange sorbents have not been used in HPLC-SPE-NMR analysis of natural products. In contrast to GP resin this material showed good retention and elution characteristics for retention and elution of alkaloids. As well the use of methanol-d(4) containing 1% aqueous NaOD (40%) as methanol-d(4) containing 5% aqueous NH(4)OH (30%) as eluents were successful, even though elution of alkaloids with pK(a) of the corresponding acid above 10 proved difficult. Alkaloid extracts of Huperzia selago containing complex aliphatic alkaloids and Triclisia patens containing bisbenzylisoquinoline alkaloids were used for validation of the protocols for analysis of a diverse collection of alkaloids. Mixed mode cation exchange sorbent was efficient for trapping and elution of both types of alkaloids as evidenced by acquisition of 2D NMR data for all trapped compounds. In contrast, GP resin proved only viable for all the H. selago alkaloids whereas trapping and elution of bisbenzylisoquinoline alkaloids were dubious. PMID:23195707

  12. Torsional resonances in magnetoelastic bimorphs

    SciTech Connect

    Peuzin, J.C.; Mackay, K. [Laboratoire de Magnetisme Louis Neel, CNRS, BP166, 38042 Grenoble Cedex 9 (France)] [Laboratoire de Magnetisme Louis Neel, CNRS, BP166, 38042 Grenoble Cedex 9 (France)

    1997-02-01

    In this paper, we show that torsional as well as flexion modes can be excited rather naturally in a magnetoelastic bimorph. This behavior is in contrast with that of usual piezoelectric bimorphs in which only flexion modes can be excited. We describe experimental results on the torsional resonances of bimorphs composed of a glass substrate and a highly magnetostrictive thin film of (TbDy)(FeCo){sub 2} and show how basic linear piezomagnetic constants may be extracted from the resonance data. Finally, we discuss some possible applications of torsional resonance in magnetoelastic bimorphs. {copyright} {ital 1997 American Institute of Physics.}

  13. Optical resonator

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, Shervin (Inventor); Vanzyl, Jakob J. (Inventor); Yariv, Amnon (Inventor)

    2006-01-01

    The invention discloses a semi-ring Fabry-Perot (SRFP) optical resonator structure comprising a medium including an edge forming a reflective facet and a waveguide within the medium, the waveguide having opposing ends formed by the reflective facet. The performance of the SRFP resonator can be further enhanced by including a Mach-Zehnder interferometer in the waveguide on one side of the gain medium. The optical resonator can be employed in a variety of optical devices. Laser structures using at least one SRFP resonator are disclosed where the resonators are disposed on opposite sides of a gain medium. Other laser structures employing one or more resonators on one side of a gain region are also disclosed.

  14. Contour extraction from cardiac MRI studies using snakes

    Microsoft Academic Search

    Surendra Ranganath

    1995-01-01

    The author investigated automatic extraction of left ventricular contours from cardiac magnetic resonance imaging (MRI) studies. The contour extraction algorithms were based on active contour models, or snakes. Based on cardiac MR image characteristics, the author suggested algorithms for extracting contours from these large data sets. The author specifically considered contour propagation methods to make the contours reliable enough despite

  15. Tooth Extraction

    MedlinePLUS

    ... 3 to 4 hours after the procedure The extraction site becomes very painful -- This may be a sign that you have developed a dry socket. If you have an infection, your dentist usually will prescribe antibiotics.

  16. Fluid extraction

    DOEpatents

    Wai, Chien M. (Moscow, ID); Laintz, Kenneth E. (Los Alamos, NM)

    1999-01-01

    A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The method is particularly useful for extracting actinides and lanthanides from acidic solutions. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

  17. Negative effective gravity in water waves by periodic resonator arrays.

    PubMed

    Hu, Xinhua; Chan, C T; Ho, Kai-Ming; Zi, Jian

    2011-04-29

    Based on analytic derivations and numerical simulations, we show that near a low resonant frequency water waves cannot propagate through a periodic array of resonators (bottom-mounted split tubes) as if water has a negative effective gravitational acceleration g(e) and positive effective depth h(e). This gives rise to a low-frequency resonant band gap in which water waves can be strongly reflected by the resonator array. For a damping resonator array, the resonant gap can also dramatically modify the absorption efficiency of water waves. The results provide a mechanism to block water waves and should find applications in ocean wave energy extraction. PMID:21635037

  18. Dark resonance

    SciTech Connect

    An, Haipeng; Pospelov, Maxim, E-mail: han@perimeterinstitute.ca, E-mail: mpospelov@perimeterinstitute.ca [Perimeter Institute for Theoretical Physics, Waterloo, ON, N2J 2W9 (Canada)

    2012-11-01

    We construct explicit models of particle dark matter where the attractive force in the dark matter sector creates a narrow near-threshold resonance that qualitatively changes the energy dependence of the annihilation cross section. In these models, the resonant enhancement of the dark matter annihilation can easily source the excess of energetic leptons observed by the PAMELA experiment. The distinct feature of these models is that by construction the enhancement of the annihilation cross section shuts off when the dark matter velocity falls below the typical Milky Way values, thus automatically satisfying constraints on dark matter annihilation imposed by the CMB anisotropies and gamma ray constraints from satellite galaxies. However, the resonant enhancement of annihilation can be probed through the most recent FERMI-LAT constraints on the diffuse galactic gamma ray emission.

  19. Resonant Tunneling Spin Pump

    NASA Technical Reports Server (NTRS)

    Ting, David Z.

    2007-01-01

    The resonant tunneling spin pump is a proposed semiconductor device that would generate spin-polarized electron currents. The resonant tunneling spin pump would be a purely electrical device in the sense that it would not contain any magnetic material and would not rely on an applied magnetic field. Also, unlike prior sources of spin-polarized electron currents, the proposed device would not depend on a source of circularly polarized light. The proposed semiconductor electron-spin filters would exploit the Rashba effect, which can induce energy splitting in what would otherwise be degenerate quantum states, caused by a spin-orbit interaction in conjunction with a structural-inversion asymmetry in the presence of interfacial electric fields in a semiconductor heterostructure. The magnitude of the energy split is proportional to the electron wave number. Theoretical studies have suggested the possibility of devices in which electron energy states would be split by the Rashba effect and spin-polarized currents would be extracted by resonant quantum-mechanical tunneling.

  20. Dark Resonance

    E-print Network

    Haipeng An; Maxim Pospelov

    2012-06-11

    We construct explicit models of particle dark matter where the attractive force in the dark matter sector creates a narrow near-threshold resonance that qualitatively changes the energy dependence of the annihilation cross section. In these models, the resonant enhancement of the dark matter annihilation can easily source the excess of energetic leptons observed by experiments on PAMELA and FERMI satellites. The distinct feature of these models is that by construction the enhancement of the annihilation cross section shuts off when the dark matter velocity falls below the typical Milky Way values, thus automatically satisfying constraints on dark matter annihilation imposed by the CMB anisotropies and gamma ray constraints from satellite galaxies.

  1. Extractable resources

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The use of information from space systems in the operation of extractive industries, particularly in exploration for mineral and fuel resources was reviewed. Conclusions and recommendations reported are based on the fundamental premise that survival of modern industrial society requires a continuing secure flow of resources for energy, construction and manufacturing, and for use as plant foods.

  2. Information extraction

    Microsoft Academic Search

    L. Zhang; C. Hoede

    2002-01-01

    In this paper we present a new approach to extract relevant information by knowledge graphs from natural language text. We give a multiple level model based on knowledge graphs for describing template information, and investigate the concept of partial structural parsing. Moreover, we point out that expansion of concepts plays an important role in thinking, so we study the expansion

  3. Building Resonance

    NSDL National Science Digital Library

    Jeffrey Barker

    This demonstration of how buildings respond to seismic shaking uses cardboard and stiff paper (such as postcards or computer cards). The effects of building resonance can be found by experimenting with taller and shorter buildings, and varying the frequency of shaking.

  4. Direct measurement of the intrinsic linewidth of a resonant state

    NASA Astrophysics Data System (ADS)

    Kobos, Zachary; Reed, Mark

    2015-03-01

    We have applied inelastic electron tunneling spectroscopy (IETS) techniques to a resonantly-coupled system to determine quantitative differences in resonant versus non-resonant IETS. We use as a model system a set of GaAs-AlGaAs resonant tunneling diodes (RTDs)(footnote: with different barrier widths to tune resonant state linewidths and transmission coefficients. Modulation-broadening studies confirm theoretical predictions; however, the thermal dependence is markedly different than expected from classical IETS theory. An analysis of resonance shut-off reveals that the thermal dependence reflects the thermal broadening of the injector and resonant state density of states. Using this analysis, we show that one can extract both the transmission coefficient and the intrinsic linewidth of the resonant state. This is compared for RTDs of different tunneling barrier widths, and we observe the expected increase in resonance width for thinner barriers. This work was supported by the National Science Foundation.

  5. DNA Extraction

    NSDL National Science Digital Library

    Teachers' Domain presents this interactive, adapted from the University of Nebraska's Plant and Soil Science eLibrary, with reading material and animations to help students learn the basics of DNA extraction. The lesson is divided into and introduction and the four processes involved: cell lysis, dismantling the cell membrane, removing unwanted cell parts, and precipitating the DNA. On the site, visitors will also find a supplemental background essay, discussion questions, and standards alignment from Teachers' Domain.

  6. Microwave energy storage in resonant cavities

    SciTech Connect

    Alvarez, R.A.

    1983-02-01

    One method of generating short, high-power microwave pulses is to store rf energy in a resonant cavity over a relatively long fill time and extract is rapidly. A power gain roughly equal to the ratio of fill time to extraction time can be obtained. During the filling of a resonant cavity some of the energy is lost in heating the cavity walls, and some will generally be reflected at the input coupling of the cavity. In this paper we discuss the time dependence of the stored energy and related quantities and the way in which it depends on the coupling of the source to the cavity.

  7. If It's Resonance, What is Resonating?

    ERIC Educational Resources Information Center

    Kerber, Robert C.

    2006-01-01

    The phenomenon under the name "resonance," which, is based on the mathematical analogy between mechanical resonance and the behavior of wave functions in quantum mechanical exchange phenomena was described. The resonating system does not have a structure intermediate between those involved in the resonance, but instead a structure which is further…

  8. All-Resonant Control of Superconducting Resonators

    E-print Network

    Frederick W. Strauch

    2012-08-17

    An all-resonant method is proposed to control the quantum state of superconducting resonators. This approach uses a tunable artificial atom linearly coupled to resonators, and allows for efficient routes to Fock state synthesis, qudit logic operations, and synthesis of NOON states. This resonant approach is theoretically analyzed, and found to perform signficantly better than existing proposals using the same technology.

  9. LLC resonant converter with two resonant tanks

    Microsoft Academic Search

    Eun-Soo Kim; Joo-Hoon Kim; Kwang-Ho Lee; Yong-Seog Jeon; Jae-Sam Lee; Dong-Young Huh

    2010-01-01

    To cope with the high power density and low cost in switching power supply, LLC resonant converters with the two resonant tank circuits composed of resonance capacitors and two transformers are proposed in this paper. Each transformers used for the proposed resonant circuits are parallel connected in the primary and series connected in the secondary to reduce the current unbalance.

  10. Detection of Kestoses and Kestose-Related Oligosaccharides in Extracts of Festuca arundinacea, Dactylis glomerata L., and Asparagus officinalis L. Root Cultures and Invertase by 13C and 1H Nuclear Magnetic Resonance Spectroscopy 1

    PubMed Central

    Forsythe, Kathlene L.; Feather, Milton S.; Gracz, Hanna; Wong, Tuck C.

    1990-01-01

    A previous study (KL Forsythe, MS Feather [1989] Carbohydr Res 185: 315-319) showed that 13C nuclear magnetic resonance spectroscopy can be used to detect and identify mixtures of 1-kestose and neokestose after conversion to the acetate derivatives. In this study, unequivocal assignments are made for the anomeric carbon and proton signals for the above two trisaccharide acetates as well as for 6-kestose hendecaacetate and for nystose tetradecaacetate (a 1-kestose-derived tetrasaccharide). A number of oligosaccharide fractions were isolated from several plant species, converted to the acetates, and nuclear magnetic resonance spectra obtained. Using the above reference data, the following information was obtained. The trisaccharide fraction from Dactylis glomerata L. stem tissue and Asparagus officinalis L. roots contain both 1-kestose and neokestose, and the tetrasaccharide fractions contain three components, one of which is nystose. Penta- and hexasaccharide acetates were also isolated from A. officinalis L. roots and were found to contain, respectively, four and at least five components. All components of both of the above species appear to contain a kestose residue and to be produced by the sequential addition of fructofuranosyl units to these. The trisaccharide fraction from Festuca arundinacea is complex, and contains at least five different components, two of which appear to be 1-kestose and neokestose. PMID:16667365

  11. Detection of kestoses and kestose-related oligosaccharides in extracts of Festuca arundinacea, Dactylis glomerate L. , and Asparagus officinalis L. root cultures and invertase by sup 13 C and sup 1 H nuclear magnetic resonance spectroscopy

    SciTech Connect

    Forsythe, K.L.; Feather, M.S.; Gracz, H.; Wong, T.C. (Univ. of Missouri, Columbia (USA))

    1990-04-01

    Previous studies show that {sup 13}C nuclear magnetic resonance spectroscopy can be used to detect and identify mixtures of 1-kestose and neokestose after conversion to the acetate derivatives. In this study, unequivocal assignments are made for the anomeric carbon and proton signals for the above two trisaccharide acetates as well as for 6-kestose hendecaacetate and for nystose tetradecaacetate (a 1-kestose-derived tetrasaccharide). A number of oligosaccharide fractions were isolated from several plant species, converted to the acetates, and nuclear magnetic resonance spectra obtained. Using the above reference data, the following information was obtained. The trisaccharide fraction from Dactylis gomerata L. stem tissue and Asparagus officinalis L. roots contain both 1-kestose and neokestose, and the tetrasaccharide fractions contain three components, one of which is nystose. Penta- and hexasaccharide acetates were also isolated from A. officinalis L. roots and were found to contain, respectively, four and at least five components. All components of both of the above species appear to contain a kestose residue and to be produced by the sequential addition of fructofuranosyl units to these. The trisaccharide fraction from Festuca arundinacea is complex, and contains at least five different components, two of which appear to be 1-kestose and neokestose.

  12. Resonance Rings

    NSDL National Science Digital Library

    This is an activity about resonance and where it is found in related to astronomy. Learners will construct two differently sized rings out of file folder paper and tape them to a piece of cardboard. Next, they will shake the cardboard from side to side, which shakes the rings, and observe what happens when the frequency of the shaking is gradually increased. This activity is from the Stanford Solar Center's All About the Sun: Sun and Stars activity guide for Grades 5-8 and can also accompany the Stanford Solar Center's Build Your Own Spectroscope activity.

  13. ODF MAXIMA EXTRACTION IN SPHERICAL HARMONIC REPRESENTATION

    E-print Network

    By Iman Aganj Christophe Lenglet and Guillermo Sapiro IMA Preprint Series # 2309 ( May 2010 ) INSTITUTE Extraction in Spherical Harmonic Representation via Analytical Search Space Reduction Iman Aganj1 of Minnesota, USA 2 Center for Magnetic Resonance Research, University of Minnesota, USA {iman, clenglet

  14. High-Field Electron Paramagnetic Resonance and Density Functional Theory Study of Stable Organic Radicals in Lignin: Influence of the Extraction Process, Botanical Origin, and Protonation Reactions on the Radical g Tensor.

    PubMed

    Bährle, Christian; Nick, Thomas U; Bennati, Marina; Jeschke, Gunnar; Vogel, Frédéric

    2015-06-18

    The radical concentrations and g factors of stable organic radicals in different lignin preparations were determined by X-band EPR at 9 GHz. We observed that the g factors of these radicals are largely determined by the extraction process and not by the botanical origin of the lignin. The parameter mostly influencing the g factor is the pH value during lignin extraction. This effect was studied in depth using high-field EPR spectroscopy at 263 GHz. We were able to determine the gxx, gyy, and gzz components of the g tensor of the stable organic radicals in lignin. With the enhanced resolution of high-field EPR, distinct radical species could be found in this complex polymer. The radical species are assigned to substituted o-semiquinone radicals and can exist in different protonation states SH3+, SH2, SH1-, and S2-. The proposed model structures are supported by DFT calculations. The g principal values of the proposed structure were all in reasonable agreement with the experiments. PMID:25978006

  15. Refining 31 P nuclear magnetic resonance spectroscopy for marine

    E-print Network

    Paytan, Adina

    31 P nuclear magnetic resonance (NMR) spectroscopy has recently been used to characterize phosphorus.e., no storage, refrigeration, freezing, and oven-drying and grinding) prior to extraction for solution 31 P-NMR locations. Samples were also analyzed by solid-state 31 P-NMR spectroscopy before and after extraction

  16. Regenerative feedback resonant circuit

    SciTech Connect

    Jones, A. Mark; Kelly, James F.; McCloy, John S.; McMakin, Douglas L.

    2014-09-02

    A regenerative feedback resonant circuit for measuring a transient response in a loop is disclosed. The circuit includes an amplifier for generating a signal in the loop. The circuit further includes a resonator having a resonant cavity and a material located within the cavity. The signal sent into the resonator produces a resonant frequency. A variation of the resonant frequency due to perturbations in electromagnetic properties of the material is measured.

  17. High-resolution ?-amylase assay combined with high-performance liquid chromatography-solid-phase extraction-nuclear magnetic resonance spectroscopy for expedited identification of ?-amylase inhibitors: proof of concept and ?-amylase inhibitor in cinnamon.

    PubMed

    Okutan, Leyla; Kongstad, Kenneth T; Jäger, Anna K; Staerk, Dan

    2014-11-26

    Type 2 diabetes affects millions of people worldwide, and new improved drugs or functional foods containing selective ?-amylase inhibitors are needed for improved management of blood glucose. In this article the development of a microplate-based high-resolution ?-amylase inhibition assay with direct photometric measurement of ?-amylase activity is described. The inhibition assay is based on porcine pancreatic ?-amylase with 2-chloro-4-nitrophenyl-?-D-maltotriose as substrate, which this gives a stable, sensitive, and cheap inhibition assay as requested for high-resolution purposes. In combination with HPLC-HRMS-SPE-NMR, this provides an analytical platform that allows simultaneous chemical and biological profiling of ?-amylase inhibitors in plant extracts. Proof-of-concept with an artificial mixture of six compounds-of which three are known ?-amylase inhibitors-showed that the high-resolution ?-amylase inhibition profiles allowed detection of sub-microgram amounts of the ?-amylase inhibitors. Furthermore, the high-resolution ?-amylase inhibition assay/HPLC-HRMS-SPE-NMR platform allowed identification of cinnamaldehyde as the ?-amylase inhibitor in cinnamon (Cinnamomum verum Presl.). PMID:25368916

  18. Controlling carbon nanotube photoluminescence using silicon microring resonators

    NASA Astrophysics Data System (ADS)

    Noury, Adrien; Le Roux, Xavier; Vivien, Laurent; Izard, Nicolas

    2014-05-01

    We report on coupling between semiconducting single-wall carbon nanotubes (s-SWNT) photoluminescence and silicon microring resonators. Polyfluorene extracted s-SWNT deposited on such resonators exhibit sharp emission peaks, due to interaction with the cavity modes of the microring resonators. Ring resonators with radius of 5 ?m and 10 ?m were used, reaching quality factors up to 4000 in emission. These are among the highest values reported for carbon nanotubes coupled with an integrated cavity on silicon platform, which open up the possibility to build s-SWNT based efficient light source on silicon.

  19. Controlling carbon nanotube photoluminescence using silicon microring resonators.

    PubMed

    Noury, Adrien; Le Roux, Xavier; Vivien, Laurent; Izard, Nicolas

    2014-05-30

    We report on coupling between semiconducting single-wall carbon nanotubes (s-SWNT) photoluminescence and silicon microring resonators. Polyfluorene extracted s-SWNT deposited on such resonators exhibit sharp emission peaks, due to interaction with the cavity modes of the microring resonators. Ring resonators with radius of 5 ?m and 10 ?m were used, reaching quality factors up to 4000 in emission. These are among the highest values reported for carbon nanotubes coupled with an integrated cavity on silicon platform, which open up the possibility to build s-SWNT based efficient light source on silicon. PMID:24787283

  20. Resonant cortical dynamics of speech perception

    NASA Astrophysics Data System (ADS)

    Grossberg, Stephen

    2003-04-01

    What is the neural representation of a speech code as it evolves in time? How do listeners integrate temporally distributed phonemic information into coherent representations of syllables and words? How does the brain extract invariant properties of variable-rate speech? This talk describes a neural model that suggests answers to these questions, while quantitatively simulating speech and word recognition data. The conscious speech and word recognition code is suggested to be a resonant wave, and a percept of silence a temporal discontinuity in the rate that resonance evolves. A resonant wave emerges when sequential activation and storage of phonemic items in working memory provides bottom-up input to list chunks that group together sequences of items of variable length. The list chunks compete and winning chunks activate top-down expectations that amplify and focus attention on consistent working memory items, while suppressing inconsistent ones. The ensuing resonance boosts activation levels of selected items and chunks. Because resonance occurs after working memory activation, it can incorporate information presented after intervening silence intervals, so future sounds can influence how we hear past sounds. The model suggests that resonant dynamics enable the brain to learn quickly without suffering catastrophic forgetting, as described within Adaptive Resonance Theory.

  1. Multipole Extraction: A novel, model independent method

    E-print Network

    E. Stiliaris; C. N. Papanicolas

    2007-03-20

    A novel method for extracting multipole amplitudes in the nucleon resonance region from electroproduction data is presented. The method is based on statistical concepts and it relies heavily on Monte Carlo and simulation techniques; it produces precise identification and determination of the contributing multipole amplitudes in the resonance region and for the first time a rigorous determination of the associated experimental uncertainty. The results are demonstrated to be independent of any model bias. The method is applied in the reanalysis of the $Q^{2}=0.127 GeV^2/c^2$ Bates and Mainz $N\\to \\Delta$ data.

  2. Analysis and calibration techniques for superconducting resonators.

    PubMed

    Cataldo, Giuseppe; Wollack, Edward J; Barrentine, Emily M; Brown, Ari D; Moseley, S Harvey; U-Yen, Kongpop

    2015-01-01

    A method is proposed and experimentally explored for in-situ calibration of complex transmission data for superconducting microwave resonators. This cryogenic calibration method accounts for the instrumental transmission response between the vector network analyzer reference plane and the device calibration plane. Once calibrated, the observed resonator response is analyzed in detail by two approaches. The first, a phenomenological model based on physically realizable rational functions, enables the extraction of multiple resonance frequencies and widths for coupled resonators without explicit specification of the circuit network. In the second, an ABCD-matrix representation for the distributed transmission line circuit is used to model the observed response from the characteristic impedance and propagation constant. When used in conjunction with electromagnetic simulations, the kinetic inductance fraction can be determined with this method with an accuracy of 2%. Datasets for superconducting microstrip and coplanar-waveguide resonator devices were investigated and a recovery within 1% of the observed complex transmission amplitude was achieved with both analysis approaches. The experimental configuration used in microwave characterization of the devices and self-consistent constraints for the electromagnetic constitutive relations for parameter extraction are also presented. PMID:25638068

  3. Binary Extraction in Hydrometallurgy

    Microsoft Academic Search

    A. I. KHOLKIN; G. L. PASHKOV; V. V. BELOVA

    2000-01-01

    Results obtained during technological application of binary extraction (extraction by salts of organic acids and organic bases) for recovery and separation of non-ferrous, rare, noble and associated metals are presented in the paper. The method of extraction of copper, especially from leaching solutions of oxidised ores, with the use of tertraoc-tylammonium dialkyldithiophosphate has been developed- The binary extractant is characterized

  4. Optical Fano resonance of an individual semiconductor nanostructure.

    PubMed

    Fan, Pengyu; Yu, Zongfu; Fan, Shanhui; Brongersma, Mark L

    2014-05-01

    Fano resonances with a characteristic asymmetric line shape can be observed in light scattering, transmission and reflection spectra of resonant optical systems. They result from interference between direct and indirect, resonance-assisted pathways. In the nanophotonics field, Fano effects have been observed in a wide variety of systems, including metallic nanoparticle assemblies, metamaterials and photonic crystals. Their unique properties find extensive use in applications, including optical filtering, polarization selectors, sensing, lasers, modulators and nonlinear optics. We report on the observation of a Fano resonance in a single semiconductor nanostructure, opening up opportunities for their use in active photonic devices. We also show that Fano-resonant semiconductor nanostructures afford the intriguing opportunity to simultaneously measure the far-field scattering response and the near-field energy storage by extracting photogenerated charge. Together they can provide a complete experimental characterization of this type of resonance. PMID:24747781

  5. Carbon nanotube resonators with capacitive and piezoresistive current modulation readout

    NASA Astrophysics Data System (ADS)

    Lee, Shih-Wei; Truax, Stuart; Yu, Liu; Roman, Cosmin; Hierold, Christofer

    2013-07-01

    In this work, a single-walled carbon nanotube (SWCNT) nanomechanical resonator is characterized at mechanical resonance using both capacitive modulation and piezoresistive modulation effects. The piezoresistive modulation effect is shown to be a robust method for measuring the resonant response, allowing improved detection of the SWCNT resonance by reducing the off-resonance drain current by a factor of up to 10. Equivalent circuit parameters describing the piezoelectric effect are extracted. The measured device shows a Q-factor of 91 and a piezoresistive bandgap bending of 0.04 eV/% strain for a resonance at 79.5 MHz. The SWCNT is measured at 300 K and 7 × 10-4 Pa.

  6. Integral resonator gyroscope

    NASA Technical Reports Server (NTRS)

    Shcheglov, Kirill V. (Inventor); Challoner, A. Dorian (Inventor); Hayworth, Ken J. (Inventor); Wiberg, Dean V. (Inventor); Yee, Karl Y. (Inventor)

    2008-01-01

    The present invention discloses an inertial sensor having an integral resonator. A typical sensor comprises a planar mechanical resonator for sensing motion of the inertial sensor and a case for housing the resonator. The resonator and a wall of the case are defined through an etching process. A typical method of producing the resonator includes etching a baseplate, bonding a wafer to the etched baseplate, through etching the wafer to form a planar mechanical resonator and the wall of the case and bonding an end cap wafer to the wall to complete the case.

  7. Phase I ResonantSonic CRADA report

    SciTech Connect

    Richterich, L.R.; Amos, L.O.; Fancher, J.D.; McLellan, G.W.; Setzer, W.V.; Tuttle, B.G. [Westinghouse Hanford Co., Richland, WA (United States); Hockey, R.L.; Ferris, R.H.; Riechers, D.M.; Pitman, S.G. [Pacific Northwest Lab., Richland, WA (United States)

    1994-03-28

    This test report describes the Phase 1 testing and results of the ResonantSonic drilling method. This effort was conducted as part of a Cooperative Research and Development Agreement (CRADA) between the US Department of Energy, Pacific Northwest Laboratory, Westinghouse Hanford Company and Water Development Corporation. The purpose of this demonstration was to evaluate the Water Development Corporation`s ResonantSonic drilling system, modify components as necessary and determine compatible drilling applications for the ResonantSonic drilling method for use at facilities in the DOE complex and private industry. Initially, the ResonantSonic drill was used to drill several test holes at the Drilling Technology Test Site to assess the feasibility of drilling vertical and angle holes. After this initial phase, a 45 degree angle vapor extraction well was drilled to a depth of 168 feet at the 200 West Carbon Tetrachloride Site. This well was drilled and completed in nine days. Extensive geologic and vapor sampling were conducted while drilling this well. In addition, testing was also conducted at the test site to evaluated drilling with larger diameter casing (8 5/8 inch). Evaluation of the Resonant Sonic drilling method will be continued during the Phase 2 portion of testing to determine if improvements to the ResonantSonic system will make it a more viable method for drilling and sampling.

  8. Chaotic spectra: How to extract dynamic information

    SciTech Connect

    Taylor, H.S.; Gomez Llorente, J.M.; Zakrzewski, J.; Kulander, K.C.

    1988-10-01

    Nonlinear dynamics is applied to chaotic unassignable atomic and molecular spectra with the aim of extracting detailed information about regular dynamic motions that exist over short intervals of time. It is shown how this motion can be extracted from high resolution spectra by doing low resolution studies or by Fourier transforming limited regions of the spectrum. These motions mimic those of periodic orbits (PO) and are inserts into the dominant chaotic motion. Considering these inserts and the PO as a dynamically decoupled region of space, resonant scattering theory and stabilization methods enable us to compute ladders of resonant states which interact with the chaotic quasi-continuum computed in principle from basis sets placed off the PO. The interaction of the resonances with the quasicontinuum explains the low resolution spectra seen in such experiments. It also allows one to associate low resolution features with a particular PO. The motion on the PO thereby supplies the molecular movements whose quantization causes the low resolution spectra. Characteristic properties of the periodic orbit based resonances are discussed. The method is illustrated on the photoabsorption spectrum of the hydrogen atom in a strong magnetic field and on the photodissociation spectrum of H/sub 3//sup +/. Other molecular systems which are currently under investigation using this formalism are also mentioned. 53 refs., 10 figs., 2 tabs.

  9. MRI (Magnetic Resonance Imaging)

    MedlinePLUS

    ... Criteria for Significant Risk Investigations of Magnetic Resonance Diagnostic Devices - Guidance for Industry and Food and Drug Administration ... the Submission Of Premarket Notifications for Magnetic Resonance Diagnostic Devices (Withdrawn) A Primer on Medical Device Interactions with ...

  10. The Giant Monopole Resonance in Pb isotopes

    E-print Network

    Elias Khan

    2009-07-20

    The extraction of the nuclear incompressibility from the isoscalar giant monopole resonance (GMR) measurements is analysed. Both pairing and mutually enhanced magicity (MEM) effects play a role in the shift of the GMR energy between the doubly closed shell $^{208}$Pb nucleus and other Pb isotopes. Pairing effects are microscopically predicted whereas the MEM effect is phenomenologically evaluated. Accurate measurements of the GMR in open-shell Pb isotopes are called for.

  11. Pediatric magnetic resonance imaging

    SciTech Connect

    Cohen, M.D.

    1986-01-01

    This book defines the current clinical potential of magnetic resonance imaging and focuses on direct clinical work with pediatric patients. A section dealing with the physics of magnetic resonance imaging provides an introduction to enable clinicians to utilize the machine and interpret the images. Magnetic resonance imaging is presented as an appropriate imaging modality for pediatric patients utilizing no radiation.

  12. Nuclear Magnetic Resonance

    NASA Astrophysics Data System (ADS)

    Andrew, E. R.

    2009-06-01

    Author's preface; 1. Introduction; 2. Basic theory; 3. Experimental methods; 4. Measurement of nuclear properties and general physical applications; 5. Nuclear magnetic resonance in liquids and gases; 6. Nuclear magnetic resonance in non-metallic solids; 7. Nuclear magnetic resonance in metals; 8. Quadrupole effects; Appendices 1-6; Glossary of symbols; Bibliography and author index; Subject index.

  13. Ovenized microelectromechanical system (MEMS) resonator

    DOEpatents

    Olsson, Roy H; Wojciechowski, Kenneth; Kim, Bongsang

    2014-03-11

    An ovenized micro-electro-mechanical system (MEMS) resonator including: a substantially thermally isolated mechanical resonator cavity; a mechanical oscillator coupled to the mechanical resonator cavity; and a heating element formed on the mechanical resonator cavity.

  14. RF voltage modulation at discrete frequencies with applications to crystal channeling extraction

    SciTech Connect

    Gabella, W.; Rosenzweig, J. (California Univ., Los Angeles, CA (United States). Dept. of Physics); Kick, R. (Illinois Math and Science Academy, Aurora, Illinois (United States)); Peggs, S. (Fermi National Accelerator Lab., Batavia, IL (United States))

    1992-05-01

    RF voltage modulation at a finite number of discrete frequencies is described in a Hamiltonian resonance framework. The theory is applied to the problem of parasitic extraction of a fixed target beam from a high energy proton collider, using a bent crystal as a thin septum'' within an effective width of about one micron. Three modes of employment of discrete resonances are proposed.First, a single relatively strong static drive'' resonance may be used to excite a test proton so that it will penetrate deeply into the channeling crystal. Second, a moderately strong feed'' resonance with a ramped modulation tune may be used to adiabatically trap protons near the edge of the beam core, and transport them to the drive resonance. Third, several weak resonances may be overlapped to create a chaotic amplitude band, either to transport protons to the drive resonance, or to provide a pulse stretching'' buffer between a feed resonance and the drive resonance. Extraction efficiency is semi- quantitatively described in terms of characteristic penetration,'' depletion,'' and repetition'' times. simulations are used to quantitatively confirm the fundamental results of the theory, and to show that a prototypical extraction scheme using all three modes promises good extraction performance.

  15. Localized ferromagnetic resonance force microscopy of permalloy-cobalt films

    SciTech Connect

    Nazaretski, Evgueni [Los Alamos National Laboratory; Movshovich, Roman [Los Alamos National Laboratory; Martin, Ivar [Los Alamos National Laboratory; Cha, Kitty V [Los Alamos National Laboratory; Akhadov, Elshan A [Los Alamos National Laboratory; Obukhov, Yu [OH STATE U; Pelekhov, D C [OH STATE U; Hammel, P C [OH STATE U

    2008-01-01

    We report the Ferromagnetic Resonance Force Microscopy (FMRFM) experiments on a combined permalloy-cobalt continuous film. Our studies demonstrate the capability of FMRFM to perform local spectroscopy of different ferromagnetic materials. Theoretical analysis of the uniform resonance mode at the edge of the film provides good quantitative agreement with the experimental data. Our experiments demonstrate the micron scale lateral resolution and allow to extract local magnetic properties in continuous ferromagnetic samples.

  16. Cytoprotective agent in Lactobacillus bulgaricus extracts.

    PubMed

    Johns, Paul; Pereira, Suzette L; Leonard, Amanda E; Mukerji, Pradip; Shalwitz, Robert A; Dowlati, Lobat; Phillips, Rosalyn R; Bergana, Marti S; Holton, Jason D; Das, Tapas

    2007-02-01

    Adenosine 5'-diphosphoribose (ADP-ribose) has been identified as a significant contributor to the anti-cytotoxic activity of Lactobacillus bulgaricus extracts. Although the biological activities associated with the administration of probiotic bacteria and components thereof are sometimes attributed to the peptidoglycans that comprise a substantial portion of the Gram-positive bacterial cell wall, we found that the beta-nicotine adenine dinucleotide (NAD) hydrolysis product ADP-ribose was a significant contributor to the observed anti-cytotoxicity in our L. bulgaricus extracts. The ADP-ribose was isolated, identified, and quantitated by high performance liquid chromatography (HPLC) and by nuclear magnetic resonance (NMR) spectroscopy. ADP-ribose levels as low as 5 mg/L exhibited a measurable inhibition of tumor necrosis factor alpha (TNF-alpha) mediated cytotoxicity in an in vitro cell assay, whereas the ADP-ribose content of the L. bulgaricus extracts often exceeded 5 mg/g dry weight. PMID:17211541

  17. Identification of Benzethonium Chloride in Commercial Grapefruit Seed Extracts

    Microsoft Academic Search

    Gary R. Takeoka; Lan T. Dao; Rosalind Y. Wong; Leslie A. Harden; Noreen Mahoney

    2001-01-01

    Commercial grapefruit seed extracts (GSE) were extracted with chloroform. The solvent was evaporated, and the resulting solid was subsequently analyzed by high-performance liquid chromatography, electrospray ionization mass spectrometry, nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis (by proton-induced X-ray emission (PIXE) analysis). The main constituent was identified as benzethonium chloride, a synthetic antimicrobial agent commonly used in cosmetics and other

  18. Optical Helmholtz resonators

    NASA Astrophysics Data System (ADS)

    Chevalier, Paul; Bouchon, Patrick; Haïdar, Riad; Pardo, Fabrice

    2014-08-01

    Helmholtz resonators are widely used acoustic components able to select a single frequency. Here, based on an analogy between acoustics and electromagnetism wave equations, we present an electromagnetic 2D Helmholtz resonator made of a metallic slit-box structure. At the resonance, the light is funneled in the ?/800 apertures, and is subsequently absorbed in the cavity. As in acoustics, there is no higher order of resonance, which is an appealing feature for applications such as photodetection or thermal emission. Eventually, we demonstrate that the slit is of capacitive nature while the box behaves inductively. We derive an analytical formula for the resonance wavelength, which does not rely on wave propagation and therefore does not depend on the permittivity of the material filling the box. Besides, in contrast with half-wavelength resonators, the resonance wavelength can be engineered by both the slit aspect ratio and the box area.

  19. Method of infusion extraction

    NASA Technical Reports Server (NTRS)

    Chang-Diaz, Franklin R. (Inventor)

    1989-01-01

    Apparatus and method of removing desirable constituents from an infusible material by infusion extraction, where a piston operating in a first chamber draws a solvent into the first chamber where it may be heated, and then moves the heated solvent into a second chamber containing the infusible material, and where infusion extraction takes place. The piston then moves the solvent containing the extract through a filter into the first chamber, leaving the extraction residue in the second chamber.

  20. Endovascular extraction techniques

    PubMed Central

    Bracke, F.A.; Meijer, A.; van Gelder, B.

    2001-01-01

    The use of lead extraction is expanding with the introduction of new endovascular extraction techniques. Indications for extraction of chronically implanted pacemaker leads have been classified as mandatory, necessary or discretionary, but their rationale is often based on clinical judgement without corresponding support from the literature. We reviewed the literature of pacemaker lead-related complications as a starting point for discussing the indications for lead extraction. ImagesFigure 1Figure 2Figure 3 PMID:25696699

  1. Extracting the Inner and Outer Borders of Bladder Wall and Flattening the Extracted Wall for MR Cystography

    Microsoft Academic Search

    Z. Liang; C. Duan; D. Gu; H. Lu

    \\u000a This paper presents a magnetic resonance imaging (MRI)-based virtual cystoscopy system, which extracts the bladder wall from\\u000a T1-weighted MR images where the wall is enhanced while the urine and surrounding fat tissues are suppressed by a fully non-invasive\\u000a imaging procedure. The system analyzes the extracted wall and detects abnormal features automatically. Test results are encouraging\\u000a by FROC (free response receiver

  2. Uranium extraction process

    SciTech Connect

    Rose, M.A.

    1983-05-03

    Uranium is extracted from wet process phosphoric acid by extraction with a mixture of a diorganophosphate and a neutral phosphorus compound, which is preferably a triorgano phosphine oxide, in the presence of nitrate to form an organic extract layer containing uranium and an aqueous acid layer, which are separated.

  3. Extraction of citrus glucosides

    Microsoft Academic Search

    S. A. El-Nawawi

    1995-01-01

    Hesperidin and naringin were extracted from orange peel and grapefruit peel, respectively, by treating the peel with Ca(OH)2. The effect of maturity of the peel and recycling of the extracting liquor upon the yield of glucoside were investigated. The highest yields of hesperidin were obtained from orange peel extracted at the early season, increase in maturity led to a decrease

  4. TRITIUM EXTRACTION FACILITY ALARA

    Microsoft Academic Search

    2005-01-01

    The primary mission of the Tritium Extraction Facility (TEF) is to extract tritium from tritium producing burnable absorber rods (TPBARs) that have been irradiated in a commercial light water reactor and to deliver tritium-containing gas to the Savannah River Site Facility 233-H. The tritium extraction segment provides the capability to deliver three (3) kilograms per year to the nation's nuclear

  5. In Situ Root System Architecture Extraction from Magnetic Resonance

    E-print Network

    Behnke, Sven

    the calculation of root parameter profiles as root length, surface and apex densities. The obtained root system stress, nutrient acquisition and plant yield are strongly influenced by the plant's capacity been developed for simulating nutrient and water uptake or root growth and performing "in situ

  6. Unfolding the Second Riemann sheet with Pade Approximants: hunting resonance poles

    SciTech Connect

    Masjuan, Pere [Faculty of Physics, University of Vienna. Boltzmanngasse 5, A-1090 Wien (Austria); Departamento de Fisica Teorica y del Cosmos, Universidad de Granada, Campus de Fuentenueva, E-18071 Granada (Spain)

    2011-05-23

    Based on Pade Theory, a new procedure for extracting the pole mass and width of resonances is proposed. The method is systematic and provides a model-independent treatment for the prediction and the errors of the approximation.

  7. Resonances as Probes of Heavy-Ion Collisions at ALICE

    NASA Astrophysics Data System (ADS)

    Knospe, A. G.; ALICE Collaboration

    2015-05-01

    Hadronic resonances serve as unique probes in the study of the hot and dense nuclear matter produced in heavy-ion collisions. Properties of the hadronic phase of the collision can be extracted from measurements of the suppression of resonance yields. A comparison of the transverse-momentum spectra of the ?(1020) meson and the proton (which have similar masses) can be used to study particle production mechanisms. Resonance measurements in pp collisions provide input for tuning QCD-inspired particle production models and serve as reference measurements for other collision systems. Measurements of resonances in p-Pb collisions allow nuclear effects in the absence of a hot and dense final state to be studied. The ALICE Collaboration has measured resonances in pp, p-Pb, and Pb-Pb collisions. These measurements will be discussed and compared to results from other experiments and to theoretical models.

  8. P11 Resonances with Dubna-Mainz-Taipei dynamical model for ?N scattering and pion electromagnetic production

    NASA Astrophysics Data System (ADS)

    Yang, Shin Nan; Kamalov, S. S.; Tiator, L.

    2012-04-01

    We present the results on P11 resonances obtained with Dubna-Mainz-Taipei (DMT) dynamical model for pion-nucleon scattering and pion electromagnetic production. The extracted values agree well, in general, with PDG values. One pole is found corresponding to the Roper resonance and two more resonances are definitely needed in DMT model. We further find indication for a narrow P11 resonance at around 1700 MeV with a width ~ 50 MeV in both ?N and ?? reactions.

  9. GaN resonant cavity light-emitting diodes for plastic optical fiber applications

    Microsoft Academic Search

    A. J. Shaw; A. L. Bradley; J. F. Donegan; J. G. Lunney

    2004-01-01

    The optical designs of resonant GaN light-emitting diodes (LEDs) have been determined for maximum extraction efficiency into typical plastic optical fiber of numerical aperture 0.5. An optimum extraction efficiency of 3.9% can be achieved for a practical resonant cavity LED (RCLED), taking account of current growth and processing considerations. The optimized device is a metal-active layer distributed Bragg reflector construction.

  10. Resonances on hedgehog manifolds

    E-print Network

    Pavel Exner; Jiri Lipovsky

    2013-02-21

    We discuss resonances for a nonrelativistic and spinless quantum particle confined to a two- or three-dimensional Riemannian manifold to which a finite number of semiinfinite leads is attached. Resolvent and scattering resonances are shown to coincide in this situation. Next we consider the resonances together with embedded eigenvalues and ask about the high-energy asymptotics of such a family. For the case when all the halflines are attached at a single point we prove that all resonances are in the momentum plane confined to a strip parallel to the real axis, in contrast to the analogous asymptotics in some metric quantum graphs; we illustrate it on several simple examples. On the other hand, the resonance behaviour can be influenced by a magnetic field. We provide an example of such a `hedgehog' manifold at which a suitable Aharonov-Bohm flux leads to absence of any true resonance, i.e. that corresponding to a pole outside the real axis.

  11. Large mode radius resonators

    NASA Technical Reports Server (NTRS)

    Harris, Michael R.

    1987-01-01

    Resonator configurations permitting operation with large mode radius while maintaining good transverse mode discrimination are considered. Stable resonators incorporating an intracavity telescope and unstable resonator geometries utilizing an output coupler with a Gaussian reflectivity profile are shown to enable large radius single mode laser operation. Results of heterodyne studies of pulsed CO2 lasers with large (11mm e sup-2 radius) fundamental mode sizes are presented demonstrating minimal frequency sweeping in accordance with the theory of laser-induced medium perturbations.

  12. Resonant Optical Antennas

    Microsoft Academic Search

    P. Mühlschlegel; H.-J. Eisler; O. J. F. Martin; B. Hecht; D. W. Pohl

    2005-01-01

    We have fabricated nanometer-scale gold dipole antennas designed to be resonant at optical frequencies. On resonance, strong field enhancement in the antenna feed gap leads to white-light supercontinuum generation. The antenna length at resonance is considerably shorter than one-half the wavelength of the incident light. This is in contradiction to classical antenna theory but in qualitative accordance with computer simulations

  13. Trimming of Microring Resonators

    Microsoft Academic Search

    D. K. Sparacin; J. P. Lock; C. Hong; K. K. Gleason; L. C. Kimerling; J. Michel

    Microring resonators are basic building blocks of photonic circuits, enabling complex functionality for optical systems. However, as micro-ring resonator diameters shrink to less than 10 µm, non-deterministic pattern-transfer errors limit dimensional precision and preclude the fabrication of identical devices across an entire wafer. Thus, the ability to precisely trim microring resonators becomes increasingly important. Microring trimming is typically done by

  14. Thermal Resonance Fusion

    E-print Network

    Bao-Guo Dong

    2015-07-07

    We first show a possible mechanism to create a new type of nuclear fusion, thermal resonance fusion, i.e. low energy nuclear fusion with thermal resonance of light nuclei or atoms, such as deuterium or tritium. The fusion of two light nuclei has to overcome the Coulomb barrier between these two nuclei to reach up to the interacting region of nuclear force. We found nuclear fusion could be realized with thermal vibrations of crystal lattice atoms coupling with light atoms at low energy by resonance to overcome this Coulomb barrier. Thermal resonances combining with tunnel effects can greatly enhance the probability of the deuterium fusion to the detectable level. Our low energy nuclear fusion mechanism research - thermal resonance fusion mechanism results demonstrate how these light nuclei or atoms, such as deuterium, can be fused in the crystal of metal, such as Ni or alloy, with synthetic thermal vibrations and resonances at different modes and energies experimentally. The probability of tunnel effect at different resonance energy given by the WKB method is shown that indicates the thermal resonance fusion mode, especially combined with the tunnel effect, is possible and feasible. But the penetrating probability decreases very sharply when the input resonance energy decreases less than 3 keV, so for thermal resonance fusion, the key point is to increase the resonance peak or make the resonance sharp enough to the acceptable energy level by the suitable compound catalysts, and it is better to reach up more than 3 keV to make the penetrating probability larger than 10^{-10}.

  15. Prospects of ion beam extraction and transport simulations (invited)

    Microsoft Academic Search

    Peter Spaedtke; K. Tinschert; R. Lang; J. Maeder; J. Rossbach; J. W. Stetson; L. Celona

    2008-01-01

    Beam profile measurements using viewing targets and emittance measurements with pepper pot devices have established new insights about the ion beam extracted from an electron cyclotron resonance ion source (ECRIS). In our measurements we have compared two different ECRISs of CAPRICE type, one source was equipped with a standard 1.0 T hexapole magnet, whereas for the other ion source a

  16. Breit-Wigner phase is a fundamental property of a resonance

    E-print Network

    S. Ceci; M. Vukši?; B. Zauner

    2015-03-16

    In the course of devising a simple method for extraction of the S-matrix poles from the data, an additional fundamental resonance property emerged. It is a reaction invariant quantity, and since it is directly related to the Breit-Wigner parameters, we call it the Breit-Wigner phase beta. We propose that this beta is added in resonant data tables.

  17. Singular boundary resonance with turning point resonance

    SciTech Connect

    Wazwaz, A.M.; Hanson, F.B.

    1986-12-01

    The resonance criteria of the singularly perturbed equation, 1/2epsilonchirho(chi;epsilon)u/sub xx/+chi(a-chi)q(chi;epsilon)u/sub x/=su, are investigated on 0resonance criteria and the associated eigenvalue problem to exponential precision. The eigenvalues can be identified as being dominated by the pure singular point problem, the pure turning point problem or by combinations of the two problems. An asymptotic exponential precision notation is introduced to succinctly express the resonance criteria, given to leading order in epsilon.

  18. Automated Extraction of the Cortical Sulci Based on a Supervised Learning Approach

    Microsoft Academic Search

    Zhuowen Tu; Songfeng Zheng; Alan L. Yuille; Allan L. Reiss; Rebecca A. Dutton; Agatha D. Lee; Albert M. Galaburda; Ivo D. Dinov; Paul M. Thompson; Arthur W. Toga

    2007-01-01

    It is important to detect and extract the major cor- tical sulci from brain images, but manually annotating these sulci is a time-consuming task and requires the labeler to follow complex protocols (1), (2). This paper proposes a learning-based algorithm for automated extraction of the major cortical sulci from magnetic resonance imaging (MRI) volumes and cortical surfaces. Unlike alternative methods

  19. Thesis: COLD TESTING OF A RADIAL EXTRACTION OUTPUT CAVITY FOR A

    E-print Network

    Anlage, Steven

    ABSTRACT Thesis: COLD TESTING OF A RADIAL EXTRACTION OUTPUT CAVITY FOR A FREQUENCY DOUBLING, optimization, cold test methodology and performance data of a proposed radial extraction output cavity in which accelerator structure. Cold #12;test results show that this new cavity, which has a Q of 458 and a resonant

  20. Neutral Pion Electroproduction in the Delta Resonance Region

    SciTech Connect

    Anthony Villano

    2007-11-01

    The electroproduction of baryon resonances at high Q2 is examined. Analysis focuses on the Delta(1232) resonance via exclusive pseudoscalar meson production of À0 particles. Differential cross sections are extracted for exclusive À0 electroproduction. In the central invariant mass (W) region the cross sections are used to extract resonant multipole amplitudes. In particular, the ratio of the electric quadrupole to magnetic dipole amplitudes (E2/M1) will be discussed for the Delta(1232) resonance. The transition to pQCD is discussed in terms of E2/M1 and other multipoles. The helicity amplitude A3/2 can be used as a baryon helicity conservation meter in this context and will be discussed. The fast shrinking of the resonant contribution in the Delta region is observed at this high momentum transfer. Apart from the observables related to pQCD scaling, the transition form factor G#23;M is extracted along with the scalar to magnetic dipole ratio C2/M1.

  1. Near-field microwave probe for local ferromagnetic resonance characterization

    Microsoft Academic Search

    Dragos I. Mircea; T. W. Clinton

    2007-01-01

    A local ferromagnetic resonance (FMR) technique using a thin-film microwave probe fabricated on coaxial transmission line is presented. Some key features of this probe are its micron-scale size coupled with broadband FMR characterization and mobility: a small area of any location on a magnetic medium can be probed. Permeability of Permalloy (Py) films has been measured, where the authors extract

  2. Resonance-assisted decay of nondispersive wave packets.

    PubMed

    Wimberger, Sandro; Schlagheck, Peter; Eltschka, Christopher; Buchleitner, Andreas

    2006-07-28

    We present a quantitative semiclassical theory for the decay of nondispersive electronic wave packets in driven, ionizing Rydberg systems. Statistically robust quantities are extracted combining resonance-assisted tunneling with subsequent transport across chaotic phase space and a final ionization step. PMID:16907569

  3. Solvent extraction of diatomite

    SciTech Connect

    Williams, W.

    1984-07-24

    There is provided a method of extracting hydrocarbons from a diatomite ore. The particle size of the ore is first reduced to form a processed ore. The processed ore is then mixed with a substantially irregular granular material to form an unstratified ore mixture having increased permeability to an extracting solvent. The unstratified ore mixture is then permeated with an extracting solvent to obtain a hydrocarbon-solvent stream from which hydrocarbons are subsequently separated. The irregular granular material may be sand.

  4. Supercritical solvent coal extraction

    NASA Technical Reports Server (NTRS)

    Compton, L. E. (inventor)

    1984-01-01

    Yields of soluble organic extract are increased up to about 50% by the supercritical extraction of particulate coal at a temperature below the polymerization temperature for coal extract fragments (450 C.) and a pressure from 500 psig to 5,000 psig by the conjoint use of a solvent mixture containing a low volatility, high critical temperature coal dissolution catalyst such as phenanthrene and a high volatility, low critical temperature solvent such as toluene.

  5. Silicon Fishbone-Shaped Resonant-Frequency-Tunable MEMS Resonator

    Microsoft Academic Search

    S. Makita; H. Tanigawa; K. Suzuki

    2007-01-01

    In this study, a silicon fishbone-shaped resonant-frequency-tunable MEMS resonator is designed and fabricated. The resonator can vibrate in larger amplitude than conventional doubly-fixed-beam resonator and resonant frequency characteristic is tunable by selectively choosing exciting electrodes. This new resonator should be useful for wider multi-band frequency applications, for example, reference oscillator of cellular phones and multi-band tunable filters.

  6. Endovascular extraction techniques

    PubMed Central

    Bracke, F.A.; Meijer, A.; van Gelder, B.

    2001-01-01

    Introduction We report our experience with lead extraction in patients with an implantable cardioverter defibrillator (ICD) and discuss the indications for extraction in these patients. Patients Eighteen patients with an ICD (mean age 58±12 years) were referred for lead extraction: two patients with infection and 16 with lead dysfunction. Methods Lead extraction was performed with a laser sheath (Excimer) if traction with a locking device was insufficient. New leads were implanted during the same procedure, if applicable. Results Shock leads were successfully extracted in 16 patients and additional pace-sense leads in seven patients. In two patients, the shock conductor was considered unaffected and only a pace-sense lead was exchanged or an additional pace-sense lead inserted. After extraction, new shock leads were implanted in 14 patients. Major complications occurred in one patient: a pericardial tamponade after perforation of the superior caval vein necessitating acute surgery. Conclusion Lead extraction with a laser sheath is effective in ICD patients, but major complications can occur. Our current policy with malfunctioning leads is to extract all leads in which insulation defects cannot be ruled out to avoid interference, but to abandon leads that are without insulation defects and properly insulated. In case of infection, extraction remains the primary treatment of choice. PMID:25696709

  7. TRITIUM EXTRACTION FACILITY ALARA

    SciTech Connect

    Joye, BROTHERTON

    2005-04-19

    The primary mission of the Tritium Extraction Facility (TEF) is to extract tritium from tritium producing burnable absorber rods (TPBARs) that have been irradiated in a commercial light water reactor and to deliver tritium-containing gas to the Savannah River Site Facility 233-H. The tritium extraction segment provides the capability to deliver three (3) kilograms per year to the nation's nuclear weapons stockpile. The TEF includes processes, equipment and facilities capable of production-scale extraction of tritium while minimizing personnel radiation exposure, environmental releases, and waste generation.

  8. Magnetic resonance imaging: prologue

    SciTech Connect

    Jacobson, H.G.

    1987-12-11

    Magnetic resonance imaging is becoming an increasingly important method of diagnostic imaging. This new method can compete with computed tomography for several applications, especially those involving the central nervous system. Magnetic resonance imaging is rapidly evolving, and several advances can be anticipated in the near future.

  9. The Concept of Resonance

    ERIC Educational Resources Information Center

    Truhlar, Donald G.

    2007-01-01

    A general example of a delocalization system associated with a higher energy than the localized one, which suggests that it is wrong to consider delocalization as equivalent to resonance stabilization, is presented. The meaning of resonance energy as it appears in valence bond theory is described as the lowering of the calculated ground-state…

  10. The resonator handbook

    NASA Technical Reports Server (NTRS)

    Cook, Jerry D.; Zhou, Shiliang

    1993-01-01

    The purpose of this work is to extend resonator theory into the region in which the planar mirror is quite small. Results of the theoretical description are then extended to resonator design and experimental arrangements as discussed in further sections of this work. Finally, a discussion of dielectric measurements for small samples is included as a specific application of this work.

  11. Narrowband resonant transmitter

    DOEpatents

    Hutchinson, Donald P.; Simpson, Marcus L.; Simpson, John T.

    2004-06-29

    A transverse-longitudinal integrated optical resonator (TLIR) is disclosed which includes a waveguide, a first and a second subwavelength resonant grating in the waveguide, and at least one photonic band gap resonant structure (PBG) in the waveguide. The PBG is positioned between the first and second subwavelength resonant gratings. An electro-optic waveguide material may be used to permit tuning the TLIR and to permit the TLIR to perform signal modulation and switching. The TLIR may be positioned on a bulk substrate die with one or more electronic and optical devices and may be communicably connected to the same. A method for fabricating a TLIR including fabricating a broadband reflective grating is disclosed. A method for tuning the TLIR's transmission resonance wavelength is also disclosed.

  12. Resonant snubber inverter

    DOEpatents

    Lai, J.S.; Young, R.W. Sr.; Chen, D.; Scudiere, M.B.; Ott, G.W. Jr.; White, C.P.; McKeever, J.W.

    1997-06-24

    A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 14 figs.

  13. Resonant snubber inverter

    DOEpatents

    Lai, Jih-Sheng (Knoxville, TN); Young, Sr., Robert W. (Oak Ridge, TN); Chen, Daoshen (Knoxville, TN); Scudiere, Matthew B. (Oak Ridge, TN); Ott, Jr., George W. (Knoxville, TN); White, Clifford P. (Knoxville, TN); McKeever, John W. (Oak Ridge, TN)

    1997-01-01

    A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.

  14. Optical diagnostics for a ring resonator free-electron lasers

    SciTech Connect

    Laucks, M.L.; Dowell, D.H.; Lowrey, A.R. (Boeing Defense and Space Group, Seattle, WA (United States)); Bender, S.C.; Lumpkin, A.H. (Los Alamos National Lab., NM (United States)); Bentz, M.P. (Rocketdyne Div. of Rockwell International, Canoga Park, CA (United States))

    1993-02-01

    The optical cavity of the Boeing free-electron laser (FEL) was reconfigured as a semiconfocal ring resonator with two glancing incidence hyperboloid-paraboloid telescopes. The challenge for this experiment was the complexity of the ring resonator compared to the simplicity of a concentric cavity. The ring resonator's nonspherical mirror surfaces, its multiple elements, and the size of the components contributed to the problems of keeping the optical mode of the resonator matched to the electron beam in the wiggler. Several new optical diagnostics were developed to determine when the optical mode in the FEL was spatially and temporally matched to the electron beam through the wiggler. These included measurements of the focus position and Rayleigh range of the ring resonator optics to determine the spatial match of the optical mode through the wiggler, and a measurement of the position of the optical axis for multiple passes around the ring resonator to determined the stability of the resonator alignment. This paper also describes the optical measurements that were necessary to achieve reliable lasing. The techniques for measuring ring resonator Rayleigh range and focus position, multiple pass alignment, cavity length, optical energy per micropulse, peak power, optical extraction, small signal gain, ringdown loss, lasing wavelength, electron bunch pulse width, and energy slew are discussed.

  15. Extensive screening for herbal extracts with potent antioxidant properties

    PubMed Central

    Niwano, Yoshimi; Saito, Keita; Yoshizaki, Fumihiko; Kohno, Masahiro; Ozawa, Toshihiko

    2011-01-01

    This paper summarizes our research for herbal extracts with potent antioxidant activity obtained from a large scale screening based on superoxide radical (O2•?) scavenging activity followed by characterization of antioxidant properties. Firstly, scavenging activity against O2•? was extensively screened from ethanol extracts of approximately 1000 kinds of herbs by applying an electron spin resonance (ESR)-spin trapping method, and we chose four edible herbal extracts with prominently potent ability to scavenge O2•?. They are the extracts from Punica granatum (Peel), Syzygium aromaticum (Bud), Mangifera indica (Kernel), and Phyllanthus emblica (Fruit). These extracts were further examined to determine if they also scavenge hydroxyl radical (•OH), by applying the ESR spin-trapping method, and if they have heat resistance as a desirable characteristic feature. Experiments with the Fenton reaction and photolysis of H2O2 induced by UV irradiation demonstrated that all four extracts have potent ability to directly scavenge •OH. Furthermore, the scavenging activities against O2•? and •OH of the extracts of P. granatum (peel), M. indica (kernel) and P. emblica (fruit) proved to be heat-resistant. The results of the review might give useful information when choosing a potent antioxidant as a foodstuff. For instance, the four herbal extracts chosen from extensive screening possess desirable antioxidant properties. In particular, the extracts of the aforementioned three herbs are expected to be suitable for food processing in which thermal devices are used, because of their heat resistance. PMID:21297917

  16. Extensive Screening for Edible Herbal Extracts with Potent Scavenging Activity against Superoxide Anions

    Microsoft Academic Search

    Keita Saito; Masahiro Kohno; Fumihiko Yoshizaki; Yoshimi Niwano

    2008-01-01

    To search for edible herbal extracts with potent antioxidant activity, we conducted a large scale screening based on the superoxide\\u000a scavenging activity. That is, scavenging activity against superoxide anions were extensively screened from ethanol extracts\\u000a of approximately 1,000 kinds of herbs by applying an electron spin resonance (ESR)-spin trapping method. Among them we chose\\u000a four edible herbal extracts with prominently

  17. Resonant Clumping and Substructure in Galactic Disks

    NASA Astrophysics Data System (ADS)

    Molloy, Matthew; Smith, Martin C.; Shen, Juntai; Wyn Evans, N.

    2015-05-01

    We describe a method to extract resonant orbits from N-body simulations, exploiting the fact that they close in frames rotating with a constant pattern speed. Our method is applied to the N-body simulation of the Milky Way by Shen et al. This simulation hosts a massive bar, which drives strong resonances and persistent angular momentum exchange. Resonant orbits are found throughout the disk, both close to the bar and out to the very edges of the disk. Using Fourier spectrograms, we demonstrate that the bar is driving kinematic substructure even in the very outer parts of the disk. We identify two major orbit families in the outskirts of the disk, one of which makes significant contributions to the kinematic landscape, namely, the m:l = 3:?2 family, resonating with the bar. A mechanism is described that produces bimodal distributions of Galactocentric radial velocities at selected azimuths in the outer disk. It occurs as a result of the temporal coherence of particles on the 3:?2 resonant orbits, which causes them to arrive simultaneously at pericenter or apocenter. This resonant clumping, due to the in-phase motion of the particles through their epicycle, leads to both inward and outward moving groups that belong to the same orbital family and consequently produce bimodal radial velocity distributions. This is a possible explanation of the bimodal velocity distributions observed toward the Galactic anticenter by Liu et al. Another consequence is that transient overdensities appear and dissipate (in a symmetric fashion), resulting in a periodic pulsing of the disk’s surface density.

  18. Quantum Phase Extraction in Isospectral Electronic Nanostructures

    SciTech Connect

    Moon, Christopher

    2010-04-28

    Quantum phase is not a direct observable and is usually determined by interferometric methods. We present a method to map complete electron wave functions, including internal quantum phase information, from measured single-state probability densities. We harness the mathematical discovery of drum-like manifolds bearing different shapes but identical resonances, and construct quantum isospectral nanostructures possessing matching electronic structure but divergent physical structure. Quantum measurement (scanning tunneling microscopy) of these 'quantum drums' [degenerate two-dimensional electron states on the Cu(111) surface confined by individually positioned CO molecules] reveals that isospectrality provides an extra topological degree of freedom enabling robust quantum state transplantation and phase extraction.

  19. Extractive Metallurgy of Beryllium

    Microsoft Academic Search

    C. K. GUPTA; S. SAHA

    2002-01-01

    A comprehensive review of the extractive metallurgy of beryllium is presented. Due to the strategic importance and element of secrecy surrounding the metal, any open literature on beryllium is rather limited. However, this review has been made to cover all important aspects of beryllium extraction technology namely, resources of the metal; processing of ores; reduction of fluoride and oxide to

  20. Glomalin extraction and measurement

    Microsoft Academic Search

    David P. Janos; Sara Garamszegi; Bray Beltran

    2008-01-01

    We investigated extraction from soil of glomalin, a glycoprotein produced by arbuscular mycorrhizal fungi, and we examined its measurement. The most commonly used protocols for extracting glomalin require autoclaving of soil in citrate solution, followed by centrifugation to separate the supernatant, and then measurement by either Bradford protein assay or enzyme-linked immunosorbent assay (ELISA). We found that lengthening the time

  1. Supercritical fluid extraction

    Microsoft Academic Search

    Joseph L. Hedrick; Leah J. Mulcahey; Larry T. Taylor

    1992-01-01

    Supercritical fluid extraction (SFE) provides for the first time a viable option to conventional and widely used Soxhlet extraction. The ability to change the solvating power of a single supercritical fluid by changing its density is an exceedingly attractive feature. An environmentally safe alternative such as supercritical carbon dioxide to organochlorine solvents which are widely used today in many government

  2. Distribution behavior of astatine: Solvent extraction and back extraction

    Microsoft Academic Search

    M. S. Sultana; A. Toyoshima; N. Takahashi; H. Baba

    2001-01-01

    The distribution behavior of astatine was studied at tracer concentrations and over a wide range of carrier iodide concentration in both solvent extraction and back extraction processes. Astatine compounds were extracted instantly into the organic solvent, CS2 from the carrier free and carrier iodide containing solutions. Back extraction of astatine with various NaOH solutions followed by solvent extraction caused the

  3. LABCOM resonator Phase 3

    SciTech Connect

    Keres, L.J.

    1990-11-01

    The purpose of this project was to develop quartz crystal resonator designs, production processes, and test capabilities for 5-MHz, 6.2-MHz, and 10-MHz resonators for Tactical Miniature Crystal Oscillator (TMXO) applications. GE Neutron Devices (GEND) established and demonstrated the capability to produce and test quartz crystal resonators for use in the TMXO developed by the US Army ERADCOM (now LABCOM). The goals in this project were based on the ERADCOM statement of work. The scope of work indicated that the resonator production facilities for this project would not be completely independent, but that they would be supported in part by equipment and processes in place at GEND used in US Department of Energy (DOE) work. In addition, provisions for production test equipment or or eventual technology transfer costs to a commercial supplier were clearly excluded from the scope of work. The demonstrated technical capability of the deep-etched blank design is feasible and practical. It can be manufactured in quantity with reasonable yield, and its performance is readily predictable. The ceramic flatpack is a very strong package with excellent hermeticity. The four-point mount supports the crystal to reasonable shock levels and does not perturb the resonator's natural frequency-temperature behavior. The package can be sealed with excellent yields. The high-temperature, high-vacuum processing developed for the TMXO resonator, including bonding the piezoid to its mount with conductive polyimide adhesive, is consistent with precision resonator fabrication. 1 fig., 6 tabs.

  4. Time scales in nuclear giant resonances

    E-print Network

    WD Heiss; RG Nazmitdinov; FD Smit

    2009-12-18

    We propose a general approach to characterise fluctuations of measured cross sections of nuclear giant resonances. Simulated cross sections are obtained from a particular, yet representative self-energy which contains all information about fragmentations. Using a wavelet analysis, we demonstrate the extraction of time scales of cascading decays into configurations of different complexity of the resonance. We argue that the spreading widths of collective excitations in nuclei are determined by the number of fragmentations as seen in the power spectrum. An analytic treatment of the wavelet analysis using a Fourier expansion of the cross section confirms this principle. A simple rule for the relative life times of states associated with hierarchies of different complexity is given.

  5. Time scales in nuclear giant resonances

    SciTech Connect

    Heiss, W. D. [National Institute for Theoretical Physics, Stellenbosch Institute for Advanced Study, and Institute of Theoretical Physics, University of Stellenbosch, 7602 Matieland (South Africa); Nazmitdinov, R. G. [Department de Fisica, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, RU-141980 Dubna (Russian Federation); Smit, F. D. [iThemba LABS, Post Office Box 722, Somerset West 7129 (South Africa)

    2010-03-15

    We propose a general approach to characterise fluctuations of measured cross sections of nuclear giant resonances. Simulated cross sections are obtained from a particular, yet representative, self-energy that contains all information about fragmentations. Using a wavelet analysis, we demonstrate the extraction of time scales of cascading decays into configurations of different complexity of the resonance. We argue that the spreading widths of collective excitations in nuclei are determined by the number of fragmentations as seen in the power spectrum. An analytic treatment of the wavelet analysis using a Fourier expansion of the cross section confirms this principle. A simple rule for the relative lifetimes of states associated with hierarchies of different complexity is given.

  6. The market for magnetic resonance spectroscopy

    SciTech Connect

    Carlson, L.

    1990-01-01

    The medical market is, at present, the most dominant market for low T{sub c} superconductors. Indeed, without magnetic resonance imaging (MRI), there would hardly be a low T{sub c} superconductor market at all. According to the author, any development that can expand the medical market for MRI machines would be a welcome one. This paper reports how the recent advances in magnetic resonance spectroscopy (MRS) are such a development. While the principle of MRS has bee around as long as MRI, only recently have advances in technique, computer programming and magnet technology allowed MRS to advance to a point where it may become an important technology-one that could increase the medical market for superconductors. The author discussed how MRS can be used to analyze oil core samples for their oil content, oil/water ratios, how the oil is bound and how to extract it.

  7. On-line trace enrichment in hyphenated liquid chromatography–nuclear magnetic resonance spectroscopy

    Microsoft Academic Search

    J. A de Koning; A. C. Hogenboom; T. Lacker; S. Strohschein; K. Albert; U. A. Th Brinkman

    1998-01-01

    The potential of on-line trace enrichment combined with column liquid chromatography–nuclear magnetic resonance detection (LC–NMR) is demonstrated for the identification of hop bitter acids in hop extracts. By performing on-line solid-phase extraction on 1–5 ml of hop extract (which contains the six major hop bitter acids) the detection\\/analysis time in the stopped-flow detection mode could be reduced 4-fold, from 60

  8. Resonant optical antennas.

    PubMed

    Mühlschlegel, P; Eisler, H-J; Martin, O J F; Hecht, B; Pohl, D W

    2005-06-10

    We have fabricated nanometer-scale gold dipole antennas designed to be resonant at optical frequencies. On resonance, strong field enhancement in the antenna feed gap leads to white-light supercontinuum generation. The antenna length at resonance is considerably shorter than one-half the wavelength of the incident light. This is in contradiction to classical antenna theory but in qualitative accordance with computer simulations that take into account the finite metallic conductivity at optical frequencies. Because optical antennas link propagating radiation and confined/enhanced optical fields, they should find applications in optical characterization, manipulation of nanostructures, and optical information processing. PMID:15947182

  9. Spin Resonance Strength Calculations

    SciTech Connect

    Courant, E. D. [Brookhaven National Laboratory, Upton NY 11973 (United States)

    2009-08-04

    In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

  10. Evaluations of Resonance Parameters and Resonance Integral of Tungsten

    NASA Astrophysics Data System (ADS)

    Moinul Haque Meaze, A. K. M.

    2007-03-01

    I present evaluated values of resonance parameters and resonance integral for natural tungsten on the basis of experimental transmissions data obtained at the Pohang Neutron Facility (PNF), Republic of Korea. Resonance parameters were obtained by using the Bayesian code SAMMY. The output values of SAMMY were used to evaluate the resonance integral for the capture cross-section.

  11. Evaluating High Order resonances using Resonant Normal Forms

    Microsoft Academic Search

    Ezio Todesco; F Schmidt

    1996-01-01

    Resonant normal forms allow to study various aspects of resonances up to high orders. We apply these techniques to evaluate resonances in four phase space variables. The input is truncated one-turn map derived from standard tracking codes. A code automatically finds fixed line locations in phase space resonances up to a desired order. The island widths and the island tunes

  12. Parametric resonance and Hopf bifurcation analysis for a MEMS resonator

    E-print Network

    Hulshof, Joost

    Parametric resonance and Hopf bifurcation analysis for a MEMS resonator Cas van der Avoort , Rein van der Hout , and Joost Hulshof January 18, 2010 Abstract We study the response of a MEMS resonator with experimental observations. Keywords MEMS resonator, clipping, beating, Hopf bifurcation. 1 Introduction

  13. Review: Magnetic resonance imaging techniques in ophthalmology

    PubMed Central

    Fagan, Andrew J.

    2012-01-01

    Imaging the eye with magnetic resonance imaging (MRI) has proved difficult due to the eye’s propensity to move involuntarily over typical imaging timescales, obscuring the fine structure in the eye due to the resulting motion artifacts. However, advances in MRI technology help to mitigate such drawbacks, enabling the acquisition of high spatiotemporal resolution images with a variety of contrast mechanisms. This review aims to classify the MRI techniques used to date in clinical and preclinical ophthalmologic studies, describing the qualitative and quantitative information that may be extracted and how this may inform on ocular pathophysiology. PMID:23112569

  14. The unsaturated bistable stochastic resonance system.

    PubMed

    Zhao, Wenli; Wang, Juan; Wang, Linze

    2013-09-01

    We investigated the characteristics of the output saturation of the classical continuous bistable system (saturation bistable system) and its impact on stochastic resonance (SR). We further proposed a piecewise bistable SR system (unsaturated bistable system) and developed the expression of signal-to-noise ratio (SNR) using the adiabatic approximation theory. Compared with the saturation bistable system, the SNR is significantly improved in our unsaturated bistable SR system. The numerical simulation showed that the unsaturated bistable system performed better in extracting weak signals from strong background noise than the saturation bistable system. PMID:24089953

  15. Extracting the Max From a DNA Extraction

    NSDL National Science Digital Library

    Edmund Marek

    2009-01-01

    Students of all ages get a thrill out of actually seeing clumps or strands of DNA. The Biotechnology/Bioinformatics Discovery! Project, a professional development workshop offered to science teachers, has always included a DNA-extraction activity. Over the course of four years, as the authors conducted these workshops for scores of teachers, they extended and refined the DNA-extraction activity to make it relevant to middle school students. Although the protocol for this exercise is on their project website along with teaching tips, they describe here the use of oral directions to give teachers many opportunities to interact with their students, and to assess how well students can follow directions and stay focused on the task.

  16. Introduction: quantum resonances Classical and quantum mechanics

    E-print Network

    Ramond, Thierry

    : quantum resonances Classical and quantum mechanics Microlocal analysis Resonances associated;..... . .... . .... . ..... . .... . .... . .... . ..... . .... . .... . .... . ..... . .... . .... . .... . ..... . .... . ..... . .... . .... . Introduction: quantum resonances Classical and quantum mechanics Microlocal analysis Resonances associated with homoclinic orbits Outline Introduction: quantum resonances Classical and quantum mechanics Microlocal

  17. Resonances in Positronium Hydride

    NASA Technical Reports Server (NTRS)

    DiRienzi, Joseph; Drachman, Richard J.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    We re-examine the problem of calculating the positions and widths of the lowest-lying resonances in the Ps + H scattering system which consists of two electrons, one positron and one proton. The first of these resonances, for L=0, was found by the methods of complex rotation and stabilization, and later described as a Feshbach resonance lying close to a bound state in the closed-channel e (+) + H (-) system. Recently, results for the L=1 and 2 scattering states were published, and it was found, surprisingly, that there is a larae shift in the positions of these resonances. In this work we repeat the analysis for L=1 and find an unexpected explanation for the shift.

  18. Micro-machined resonator

    DOEpatents

    Godshall, N.A.; Koehler, D.R.; Liang, A.Y.; Smith, B.K.

    1993-03-30

    A micro-machined resonator, typically quartz, with upper and lower micro-machinable support members, or covers, having etched wells which may be lined with conductive electrode material, between the support members is a quartz resonator having an energy trapping quartz mesa capacitively coupled to the electrode through a diaphragm; the quartz resonator is supported by either micro-machined cantilever springs or by thin layers extending over the surfaces of the support. If the diaphragm is rigid, clock applications are available, and if the diaphragm is resilient, then transducer applications can be achieved. Either the thin support layers or the conductive electrode material can be integral with the diaphragm. In any event, the covers are bonded to form a hermetic seal and the interior volume may be filled with a gas or may be evacuated. In addition, one or both of the covers may include oscillator and interface circuitry for the resonator.

  19. Resonant ultrasound spectroscopy

    DOEpatents

    Migliori, Albert (Santa Fe, NM)

    1991-01-01

    A resonant ultrasound spectroscopy method provides a unique characterization of an object for use in distinguishing similar objects having physical differences greater than a predetermined tolerance. A resonant response spectrum is obtained for a reference object by placing excitation and detection transducers at any accessible location on the object. The spectrum is analyzed to determine the number of resonant response peaks in a predetermined frequency interval. The distribution of the resonance frequencies is then characterized in a manner effective to form a unique signature of the object. In one characterization, a small frequency interval is defined and stepped though the spectrum frequency range. Subsequent objects are similarly characterized where the characterizations serve as signatures effective to distinguish objects that differ from the reference object by more than the predetermined tolerance.

  20. Resonant Doppler velocimeter

    NASA Technical Reports Server (NTRS)

    Miles, R. B.

    1975-01-01

    Narrow linewidth tunable lasers augur a new kind of laser Doppler velocimetry employing resonant absorption and fluorescence from trace atomic species rather than scattering from particles. This technique may provide better turbulence and small volume information than present velocimetry.

  1. Exact solution of resonant modes in a rectangular resonator.

    PubMed

    Wu, Jiu Hui; Liu, A Q

    2006-06-01

    The resonant modes of rectangular two-dimensional optical resonators were analyzed exactly. Based on the characteristics of the Bessel function, the resonant frequencies of the rectangular microcavities are expressed in a simple way. In addition, a simple rule to judge when the finite length of a rectangular resonator can be considered infinite is given in realistic applications. The solution that is presented should be useful in possible applications of the rectangular resonators as filters for dense wavelength-division multiplexing. PMID:16688273

  2. Oilseed extraction process

    SciTech Connect

    Sullivan, D. A.

    1985-05-07

    A process is provided for the recovery of a separate lecithin/phosphatide-rich product during the extraction of soybeans with an isopropanol-based solvent. The invention comprises steps for contacting soybeans with solvent to obtain an extracted seed meal and a solvent extract of seedoils and lecithin and related phosphatides, cooling miscella to a temperature in the range from about 30/sup 0/ to 80/sup 0/ F., phase separating the cooled miscella, recovering from the phase separation an upper solvent-rich phase, an intermediate lecithin/phosphatide-rich phase and a lower crude oil phase, and directly recycling the solvent-rich phase to the extractor.

  3. Silicon carbide microdisk resonator.

    PubMed

    Lu, Xiyuan; Lee, Jonathan Y; Feng, Philip X-L; Lin, Qiang

    2013-04-15

    We demonstrate a silicon carbide (SiC) microdisk resonator with an intrinsic optical quality factor of 6.19×10(3), fabricated on the 3C-SiC-on-Si platform. We characterize the temperature dependence of the cavity resonance and obtain a thermo-optic coefficient of 2.92×10(-5)/K for 3C-SiC. Our simulations show that the device exhibits great potential for cavity optomechanical applications. PMID:23595466

  4. Resonant dielectric metamaterials

    DOEpatents

    Loui, Hung; Carroll, James; Clem, Paul G; Sinclair, Michael B

    2014-12-02

    A resonant dielectric metamaterial comprises a first and a second set of dielectric scattering particles (e.g., spheres) having different permittivities arranged in a cubic array. The array can be an ordered or randomized array of particles. The resonant dielectric metamaterials are low-loss 3D isotropic materials with negative permittivity and permeability. Such isotropic double negative materials offer polarization and direction independent electromagnetic wave propagation.

  5. Structure of proton resonances

    SciTech Connect

    Kraft, O.E.; Naumov, Y.V.; Sigalov, V.M.; Sizov, I.V.

    1986-11-01

    Experimental data are presented which attest to the nonstatistical nature of proton resonances for excitation energies 6--15 MeV in light and intermediate nuclei. The reduced proton widths and the absolute-width and amplitude correlations are analyzed. Special attention is devoted to the amplitude relative-phase correlations. At the end of the review a possible reason for the manifestation of the nonstatistical nature of proton resonances is discussed.

  6. Hexagonal quartz resonator

    DOEpatents

    Peters, Roswell D. M. (Rustburg, VA)

    1982-01-01

    A generally flat, relatively thin AT-cut piezoelectric resonator element structured to minimize the force-frequency effect when mounted and energized in a housing. The resonator is in the form of an equilateral hexagon with the X crystallographic axis of the crystal passing through one set of opposing corners with mounting being effected at an adjacent set of corners respectively .+-.60.degree. away from the X axis which thereby results in a substantially zero frequency shift of the operating frequency.

  7. Injector with integrated resonator

    DOEpatents

    Johnson, Thomas Edward; Ziminsky, Willy Steve; York, William David; Stevenson, Christian Xavier

    2014-07-29

    The system may include a turbine engine. The turbine engine may include a fuel nozzle. The fuel nozzle may include an air path. The fuel nozzle may also include a fuel path such that the fuel nozzle is in communication with a combustion zone of the turbine engine. Furthermore, the fuel nozzle may include a resonator. The resonator may be disposed in the fuel nozzle directly adjacent to the combustion zone.

  8. Quantum stochastic resonance

    SciTech Connect

    Loefstedt, R.; Coppersmith, S.N. (AT T Bell Laboratories, Murray Hill, New Jersey 07974 (United States))

    1994-03-28

    We demonstrate that stochastic resonance, where an increase in the noise acting on a nonlinear dynamical system increases the signal-to-noise ratio describing the response to periodic driving, can occur in quantum systems as well as classical ones. We show that quantum stochastic resonance can be observed experimentally by measuring conductance fluctuations in mesoscopic metals and describe the experimental parameters for which it occurs.

  9. Nuclear magnetic resonance gyroscope

    SciTech Connect

    Grover, B.C.

    1984-02-07

    A nuclear magnetic resonance gyro using two nuclear magnetic resonance gases, preferably xenon 129 and xenon 131, together with two alkaline metal vapors, preferably rubidium, potassium or cesium, one of the two alkaline metal vapors being pumped by light which has the wavelength of that alkaline metal vapor, and the other alkaline vapor being illuminated by light which has the wavelength of that other alkaline vapor.

  10. Resonant nonlinear ultrasound spectroscopy

    DOEpatents

    Johnson, Paul A. (Santa Fe, NM); TenCate, James A. (Los Alamos, NM); Guyer, Robert A. (Amherst, MA); Van Den Abeele, Koen E. A. (Sint-Niklaas, BE)

    2001-01-01

    Components with defects are identified from the response to strains applied at acoustic and ultrasound frequencies. The relative resonance frequency shift .vertline..DELTA..function./.function..sub.0.vertline., is determined as a function of applied strain amplitude for an acceptable component, where .function..sub.0 is the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak of a selected mode to determine a reference relationship. Then, the relative resonance frequency shift .vertline..DELTA..function./.function..sub.0 is determined as a function of applied strain for a component under test, where fo .function..sub.0 the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak to determine a quality test relationship. The reference relationship is compared with the quality test relationship to determine the presence of defects in the component under test.

  11. Radial Bragg Resonators

    NASA Astrophysics Data System (ADS)

    Scheuer, Jacob; Sun, Xiankai

    Circular resonators are promising candidates for a wide range of applications, ranging from optical communication systems through basic research involving highly confined fields and strong photon-atom interactions to biochemical and rotation sensing. The main characteristics of circular resonators are the Q factor, the free spectral range (FSR), and the modal volume, where the last two are primarily determined by the resonator radius. The total internal reflection (TIR) mechanism used for guidance in "conventional" resonators couples these attributes and limits the ability to realize compact devices exhibiting large FSR, small modal volume, and high Q. Recently, a new class of annular resonator, based on a single defect surrounded by radial Bragg reflectors, has been proposed and analyzed. The radial Bragg confinement decouples the modal volume from the Q and paves the way for the realization of compact, low-loss resonators. These properties as well as the unique mode profile of these circular Bragg nanoresonators (CBNRs) and nanolasers (CBNLs) make the devices within this class an excellent tool to realize nanometer scale semiconductor lasers and ultrasensitive detectors, as well as to study nonlinear optics.

  12. Recoil-induced Resonances as All-optical Switches

    NASA Astrophysics Data System (ADS)

    Narducci, F. A.; Desavage, S. A.; Gordon, K. H.; Duncan, D. L.; Welch, G. R.; Davis, J. P.

    2010-03-01

    We have measured recoil-induced resonances (RIR) [1,2] in our system of laser-cooled 85Rb atoms. Although this technique has been demonstrated to be useful for the purpose of extracting the cloud temperature [3], our aim was to demonstrate an all optical switch based on recoil-induced resonances. In addition to a very narrow ``free-space'' recoil-induced resonance of approximately 15 kHz, we also discovered a much broader resonance (˜30 MHz), caused by standing waves established by our trapping fields. We compare and contrast the switching dynamics of these two resonances and demonstrate optical switching using both resonances. Finally, we consider the applicability of the narrow, free-space resonance to the slowing of a weak probe field. [1] J. Guo, P.R. Berman, B. Dubetsky and G. Grynberg PRA, 46, 1426 (1992). [2] (a) P. Verkerk, B. Loumis, C. Salomon, C. Cohen-Tannoudji, J. Courtois PRL, 68, 3861 (1992). (b) G. Grynberg, J-Y Courtois, B. Lounis, P. Verkerk PRL, 72, 3017 (1994). [3] (a) T. Brzozowski, M. Brzozowska, J. Zachorowski, M. Zawada, W. Gawlik PRA, 71, 013401 (2005). (b) M. Brzozowska, T. Brzozowski J. Zachorowski, W. Gawlik PRA, 72, 061401(R), (2005).

  13. Threshold voltage extraction circuit 

    E-print Network

    Hoon, Siew Kuok

    2000-01-01

    A novel optimally self-biasing MOSFET threshold-voltage (V[]) extractor circuit is presented. It implements the most popular industrial extraction algorithm of biasing a saturated MOSFET to the linear portion of its [] versus [] characteristic...

  14. Supercritical Fluid Extraction 

    E-print Network

    Johnston, K. P.; Flarsheim, W. M.

    1984-01-01

    In supercritical fluid extraction, many options are available for achieving and controlling the desired selectivity, which is extremely sensitive to variations in pressure, temperature, and choice of solvent. The ability of supercritical fluids...

  15. Supercritical Fluid Extraction

    E-print Network

    Johnston, K. P.; Flarsheim, W. M.

    1984-01-01

    In supercritical fluid extraction, many options are available for achieving and controlling the desired selectivity, which is extremely sensitive to variations in pressure, temperature, and choice of solvent. The ability of supercritical fluids...

  16. Threshold voltage extraction circuit

    E-print Network

    Hoon, Siew Kuok

    2000-01-01

    A novel optimally self-biasing MOSFET threshold-voltage (V[]) extractor circuit is presented. It implements the most popular industrial extraction algorithm of biasing a saturated MOSFET to the linear portion of its [] versus [] characteristic...

  17. An automated and simple method for brain MR image extraction

    PubMed Central

    2011-01-01

    Background The extraction of brain tissue from magnetic resonance head images, is an important image processing step for the analyses of neuroimage data. The authors have developed an automated and simple brain extraction method using an improved geometric active contour model. Methods The method uses an improved geometric active contour model which can not only solve the boundary leakage problem but also is less sensitive to intensity inhomogeneity. The method defines the initial function as a binary level set function to improve computational efficiency. The method is applied to both our data and Internet brain MR data provided by the Internet Brain Segmentation Repository. Results The results obtained from our method are compared with manual segmentation results using multiple indices. In addition, the method is compared to two popular methods, Brain extraction tool and Model-based Level Set. Conclusions The proposed method can provide automated and accurate brain extraction result with high efficiency. PMID:21910906

  18. Standardized extracts, foods

    Microsoft Academic Search

    Robert F. Lemanske; Steve L. Taylor

    1987-01-01

    Summary  While progress has been made in the areas of food allergen characterization, both the complexity of the biochemical constituents\\u000a of food and the body’s normal physiologic (digestion) and immunologic responses to food ingestion provide challenging obstacles\\u000a to efforts aimed at developing standardized food extracts. As indicated above, while currently available food extracts can\\u000a be useful in the evaluation of food

  19. Liquid chromatographic extraction medium

    DOEpatents

    Horwitz, E. Philip (Naperville, IL); Dietz, Mark L. (Evanston, IL)

    1994-01-01

    A method and apparatus for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column is described. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water.

  20. Proton Resonance Spectroscopy in MAGNESIUM-24

    NASA Astrophysics Data System (ADS)

    Vanhoy, Jeffrey Rahn

    Excitation functions for proton elastic scattering and proton induced reactions on ('23)Na were measured with the KN Van de Graaff accelerator and associated high resolution system at Triangle Universities Nuclear Laboratory. Differential cross sections for the ('23)Na(p,p(,0)), (p,p(,1)),(p,(alpha)(,0)), and (p,(alpha)(,1)) reactions were obtained for the energy range E(,p) = 1.08 to 4.15 MeV with an overall experimental energy resolution of (TURN)400 eV. Resonance spins, parities, partial widths, and channel spin and orbital angular momentum mixing ratios were extracted with a multi-level, multi-channel R-matrix based computer program. Resonance parameters were determined for 72 levels between 12.72 and 15.05 MeV in the compound system ('24)Mg. An additional nineteen resonances were identified between 15.05 and 16.67 MeV in ('24)Mg; the resonance parameters for these states are incomplete. Two isobaric analog states were identified and two others tentatively located. Coulomb energies and proton spectroscopic factors were determined and compared with ('23)Na(d,p) spectroscopic factors. The s-wave proton strength function ratio of S(,J=2) / S(,J=1) was approximately one. This ratio can be used to set limits on the effective spin-spin interaction between projectile and target. The reduced width sum rule for proton and alpha decay is discussed and comparisons made with the present data. Results from this study indicate that additional measurements and analysis are required in several areas. Spectroscopic information on states in ('24)Na should be extended to allow additional identification of analog states. Improved methods are needed to evaluate and interpret alpha spectroscopic factors. Additional experiments to measure alpha angular distributions will be required to provide resonance parameters for states above E(,p) = 3 MeV.

  1. Experiment study of an electron cyclotron resonant ion source based on a tapered resonance cavity

    SciTech Connect

    Yang, Juan; Shi, Feng; Jin, Yizhou; Wang, Yunmin [College of Astronautics, Northwestern Polytechnic University, Xi'an, Shaanxi 710072 (China)] [College of Astronautics, Northwestern Polytechnic University, Xi'an, Shaanxi 710072 (China); Komurasaki, Kimiya [Department of Aeronautics and Astronautics, The University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-8656 (Japan)] [Department of Aeronautics and Astronautics, The University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-8656 (Japan)

    2013-12-15

    Electron cyclotron resonant plasma is one type of magnetised plasma generated by continuous microwave energy. It has the property of high degree of ionization and large volume at low gas pressure, which makes it useful for space propulsion and material processing. This article presents the experiment study of the plasma properties and ion beam extraction from an electron cyclotron resonant ion source based on a tapered resonance cavity. Optical emission spectroscopy based on a simple collisional radiation model was used for plasma diagnosis. Experiment results show that, at microwave power setting ranging from 7.06 to 17.40 W and mass flow rate ranging from 1 to 10 sccm, argon gas can be ionized. Ion beam of 109.1 mA from the ion source can be extracted at microwave power of 30 W, mass flow rate of 10 sccm, and accel voltage of 800 V. The diagnosed plasma temperature and density are 2.4–5.2 eV and 2 × 10{sup 16}–4.8 × 10{sup 17} m{sup ?3}, respectively.

  2. Ring resonator for lasers with annular gain media.

    PubMed

    Ehrlichmann, D; Habich, U; Plum, H D

    1994-10-20

    A ring resonator for lasers with annular gain media is presented. The resonator consists of two annular mirrors. While the radiation is reflected back and forth between the two annular mirrors, diffraction effects induce an additional azimuthal radiation flux. Output coupling is obtained through a decentered coupling aperture on the circumference of one of the two mirrors. The azimuthal radiation flux permits the extraction of optical power from the whole gain volume through the coupling aperture. The azimuthal radiation flux can revolve in two directions. The associated modes are degenerate, and random jumping between unidirectional and bidirectional operation is observed. Unidirectional operation has been stabilized but remains very sensitive to mirror alignment. High extraction efficiencies have been demonstrated experimentally with this resonator with a diffusion-cooled CO(2) laser and 2 times diffraction-limited beams have been obtained. An empty resonator model that shows the effect of edge diffraction at the coupling aperture on the resonator modes is also given. PMID:20941238

  3. Novel multisample dielectric resonators for electron paramagnetic resonance spectroscopy

    NASA Astrophysics Data System (ADS)

    Golovina, Iryna S.; Kolesnik, Sergiy P.; Geifman, Ilia N.; Belous, Anatoliy G.

    2010-04-01

    We have developed and tested two types of novel dielectric resonators for simultaneous recording of electron paramagnetic resonance (EPR) spectra from two to four samples. The resonator of the first type contains two holes, and the other resonator contains four holes for introduction of the samples. Also, the resonator structure includes a pair of gradient coils. Dielectric resonators made of materials with high dielectric constant with low losses can be inserted into the standard EPR cavity or waveguide in the maximum microwave magnetic field. Gradient coils are located outside the cavity (or waveguide) so that their axes are parallel to the static magnetic field. Computer simulations were made to obtain microwave characteristics of the resonators such as resonant frequency, sizes, and distribution of the fields. Spacing of the point samples and optimum value of the magnetic-field gradient have been chosen correctly. The designed resonators can be applied in express analysis using EPR technique, for instance.

  4. Solvent extraction studies of holmium with acidic extractants

    SciTech Connect

    Gaikwad, A.G.; Damodaran, A.D. (CSIR, Trivandrum (India))

    1993-03-01

    Liquid-liquid extraction studies of holmium with 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester, naphthenic, and Versatic 10 acids have been carried out. The nature of the extracted species and the extraction equilibrium constants of these systems have been determined from aqueous nitrate solution. The extraction mechanism and complexation models have been proposed. 11 refs., 8 figs.

  5. Not-so-resonant, resonant absorption

    SciTech Connect

    Brunel, F.

    1987-07-06

    When an intense electromagnetic wave is incident obliquely on a sharply bounded overdense plasma, strong energy absorption can be accounted for by the electrons that are dragged into the vacuum and sent back into the plasma with velocities vapprox. =v/sub osc/. This mechanism is more efficient than usual resonant absorption for v/sub osc//..omega..>L, with L being the density gradient length. In the very high-intensity CO/sub 2/-laser--target interaction, this mechanism may account for most of the energy absorption.

  6. Broad Feshbach resonances in collisions of ultracold Dysprosium atoms

    E-print Network

    Maier, Thomas; Kadau, Holger; Schmitt, Matthias; Wenzel, Matthias; Wink, Clarissa; Pfau, Tilman; Jachymski, Krzysztof; Julienne, Paul Sebastian

    2015-01-01

    We report on the observation of weakly-bound dimers of bosonic Dysprosium with a strong universal s-wave halo character. These states are responsible for broad magnetic Feshbach resonances. We analyze our findings using a coupled-channel theory taking into account the short range van der Waals interaction and a correction due to the strong dipole moment of Dysprosium. We are able to extract the scattering length as a function of magnetic field associated with these resonances. These results offer prospects of a tunability of the interactions in Dysprosium, which we illustrate by observing the saturation of three-body losses.

  7. Circular asymmetric Helmholtz resonators

    PubMed

    Selamet; Ji

    2000-05-01

    A three-dimensional (3D) analytical approach is developed to account for the nonplanar wave propagation in the cavity and neck of "piston-driven" circular asymmetric Helmholtz resonators. The present 3D analytical results are compared with (1) the numerical predictions from the boundary element method (BEM) to evaluate the analytical approach; and (2) the one-dimensional (1D) solution to examine the effect of nonplanar waves at area discontinuity between the neck and the cavity. In order to improve the 1D solution, the end correction is also determined by using the 3D analytical approach. The effect of neck offset on the resonance frequency of circular asymmetric Helmholtz resonators is investigated. Predictions of resonance frequency and transmission loss from the present 3D and corrected 1D analytical approaches are, respectively, identical and close to the BEM results, while the corrected 1D approach provides a better accuracy compared to the 1D solutions with Ingard's correction. Finally, the boundary element method is employed to determine the wave attenuation performance of the "pipe-mounted" Helmholtz resonators to examine the effect of multidimensional waves in the vicinity of the main duct and neck junction. PMID:10830358

  8. Resonances in Positronium Hydride

    NASA Technical Reports Server (NTRS)

    Drachman, Richard J.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Recently, Ho and his colleagues have calculated the positions and widths of a series of resonances in the Ps+H scattering system, using the complex -rotation method and have compared them with estimates that I made many years ago using a quite different technique. I assumed that the resonance mechanism was the existence in the rearrangement channel [e+ + H-] of an infinite series of perturbed Coulomb bound states. Although these must be broadened and shifted by coupling with the open scattering channel, I expected them to lie very close to the actual resonance positions. To verify this, I did a model calculation for S-waves, including the coupling, and found that the first two resonances were not shifted very far from their unperturbed position. The new, detailed calculation agrees with this result, but when the P-wave was examined it was found, surprisingly, that the lowest resonance indeed moved up in energy by a large amount. With the help of Joseph DiRienzi of the College of Notre Dame of Maryland I am now extending the old calculation to P- and D-waves, in an attempt to understand this unexpected energy shift. Results will be presented at the Workshop.

  9. Resonant ultrasound spectrometer

    DOEpatents

    Migliori, Albert (Santa Fe, NM); Visscher, William M. (Los Alamos, NM); Fisk, Zachary (Santa Fe, NM)

    1990-01-01

    An ultrasound resonant spectrometer determines the resonant frequency spectrum of a rectangular parallelepiped sample of a high dissipation material over an expected resonant response frequency range. A sample holder structure grips corners of the sample between piezoelectric drive and receive transducers. Each transducer is mounted on a membrane for only weakly coupling the transducer to the holder structure and operatively contacts a material effective to remove system resonant responses at the transducer from the expected response range. i.e., either a material such as diamond to move the response frequencies above the range or a damping powder to preclude response within the range. A square-law detector amplifier receives the response signal and retransmits the signal on an isolated shield of connecting cabling to remove cabling capacitive effects. The amplifier also provides a substantially frequency independently voltage divider with the receive transducer. The spectrometer is extremely sensitive to enable low amplitude resonance to be detected for use in calculating the elastic constants of the high dissipation sample.

  10. Nano-electromembrane extraction.

    PubMed

    Payán, María D Ramos; Li, Bin; Petersen, Nickolaj Jacob; Jensen, Henrik; Hansen, Steen Honoré; Pedersen-Bjergaard, Stig

    2013-06-27

    The present work has for the first time described nano-electromembrane extraction (nano-EME). In nano-EME, five basic drugs substances were extracted as model analytes from 200 ?L acidified sample solution, through a supported liquid membrane (SLM) of 2-nitrophenyl octyl ether (NPOE), and into approximately 8 nL phosphate buffer (pH 2.7) as acceptor phase. The driving force for the extraction was an electrical potential sustained over the SLM. The acceptor phase was located inside a fused silica capillary, and this capillary was also used for the final analysis of the acceptor phase by capillary electrophoresis (CE). In that way the sample preparation performed by nano-EME was coupled directly with a CE separation. Separation performance of 42,000-193,000 theoretical plates could easily be obtained by this direct sample preparation and injection technique that both provided enrichment as well as extraction selectivity. Compared with conventional EME, the acceptor phase volume in nano-EME was down-scaled by a factor of more than 1000. This resulted in a very high enrichment capacity. With loperamide as an example, an enrichment factor exceeding 500 was obtained in only 5 min of extraction. This corresponded to 100-times enrichment per minute of nano-EME. Nano-EME was found to be a very soft extraction technique, and about 99.2-99.9% of the analytes remained in the sample volume of 200 ?L. The SLM could be reused for more than 200 nano-EME extractions, and memory effects in the membrane were avoided by effective electro-assisted cleaning, where the electrical potential was actively used to clean the membrane. PMID:23764444

  11. Identification of benzethonium chloride in commercial grapefruit seed extracts.

    PubMed

    Takeoka, G; Dao, L; Wong, R Y; Lundin, R; Mahoney, N

    2001-07-01

    Commercial grapefruit seed extracts (GSE) were extracted with chloroform. The solvent was evaporated, and the resulting solid was subsequently analyzed by high-performance liquid chromatography, electrospray ionization mass spectrometry, nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis (by proton-induced X-ray emission [PIXE] analysis). The main constituent was identified as benzethonium chloride, a synthetic antimicrobial agent commonly used in cosmetics and other topical applications. This compound comprised 8.03% (n = 2) of the liquid GSE sample. Higher amounts of benzethonium chloride were found in powder GSE samples. PMID:11453769

  12. Coupled-Resonator-Induced Transparency

    NASA Technical Reports Server (NTRS)

    Smith, David D.; Chang, Hong-Rok; Fuller, Kirk A.; Rosenberger, A. T.; Boyd, Robert W.

    2003-01-01

    We demonstrate that a cancellation of absorption occurs on resonance for two (or any even number of) coupled optical resonators, due to mode splitting and classical destructive interference, particularly when the resonator finesse is large and the loss in the resonator furthest from the excitation waveguide is small. The linewidth and group velocity of a collection of such coupled-resonator structures may be decreased by using larger resonators of equal size, using larger resonators of unequal size where the optical path length of the larger resonator is an integer multiple of that of the smaller one, or by using a larger number of resonators per structure. We explore the analogy between these effects and electromagnetically induced transparency in an atomic system.

  13. Electrostatic (plasmon) resonances in nanoparticles

    NASA Astrophysics Data System (ADS)

    Mayergoyz, Isaak D.; Fredkin, Donald R.; Zhang, Zhenyu

    2005-10-01

    A surface integral eigenvalue based technique for the direct calculation of resonance values of the permittivity of nanoparticles, and hence resonance frequencies, is discussed. General physical properties of electrostatic (plasmon) resonances are presented. Strong orthogonality properties of resonance modes, a two-dimensional phenomenon of “twin” spectrum and explicit estimates of resonance frequencies in terms of geometrical characteristics of convex nanoparticles are reported. Second-order corrections for resonance values of the dielectric permittivity are derived. Tunability and optical controllability of plasmon resonances in semiconductor nanoparticles are discussed and, as a digression, a plausible plasmon resonance mechanism for nucleation and formation of ball lightning is outlined. An efficient numerical algorithm for the calculation of resonance frequencies is developed and illustrated by extensive computational results that are compared with theoretical results and available experimental data.

  14. Equivalent lumped elements G, L, C, and unloaded Q's of closed- and open-loop ring resonators

    Microsoft Academic Search

    Lung-Hwa Hsieh; Kai Chang

    2002-01-01

    A transmission-line model is used to extract the equivalent lumped-element circuits for the closed- and open-loop ring resonators. The unloaded Q values of the ring resonators can be calculated from the equivalent lumped elements G, L, and C. Four different configurations of microstrip ring resonators fabricated on low and high dielectric-constant substrates are used to investigate the lumped elements and

  15. Active Resonators for ADMX

    NASA Astrophysics Data System (ADS)

    Malagon, Ana; ADMX Collaboration

    2015-04-01

    The Axion Dark Matter experiment (ADMX) searches for dark matter axion particles converting into detectable photons in a microwave resonator immersed in a strong magnetic field. Here we will discuss a recently proposed technique to use active feedback in resonators as a way to increase the sensitivity of dark matter axion searches. We will briefly overview the theoretical motivation for axions and the current experimental setup of ADMX, then describe the principles of the active feedback system. Finally, we will discuss an active resonator prototype which demonstrates the improvement in signal to noise ratio. Supported by DOE Grants DE-FG02-97ER41029, DE-FG02-96ER40956, DE- AC52-07NA27344, DE-AC03-76SF00098, NSF Grant 1067242, and the Livermore LDRD program.

  16. Double entropic stochastic resonance

    NASA Astrophysics Data System (ADS)

    Burada, P. S.; Schmid, G.; Reguera, D.; Rubi, J. M.; Hänggi, P.

    2009-09-01

    We demonstrate the appearance of a purely entropic stochastic resonance (ESR) occurring in a geometrically confined system, where the irregular boundaries cause entropic barriers. The interplay between a periodic input signal, a constant bias and intrinsic thermal noise leads to a resonant ESR phenomenon in which feeble signals become amplified. This new phenomenon is characterized by the presence of two peaks in the spectral amplification at corresponding optimal values of the noise strength. The main peak is associated with the manifest stochastic resonance synchronization mechanism involving the inter-well noise-activated dynamics while a second peak relates to a regime of optimal sensitivity for intra-well dynamics. The nature of ESR, occurring when the origin of the barrier is entropic rather than energetic, offers new perspectives for novel investigations and potential applications. ESR by itself presents yet another case where one constructively can harvest noise in driven nonequilibrium systems.

  17. Quartz resonator processing system

    DOEpatents

    Peters, Roswell D. M. (Rustburg, VA)

    1983-01-01

    Disclosed is a single chamber ultra-high vacuum processing system for the oduction of hermetically sealed quartz resonators wherein electrode metallization and sealing are carried out along with cleaning and bake-out without any air exposure between the processing steps. The system includes a common vacuum chamber in which is located a rotatable wheel-like member which is adapted to move a plurality of individual component sets of a flat pack resonator unit past discretely located processing stations in said chamber whereupon electrode deposition takes place followed by the placement of ceramic covers over a frame containing a resonator element and then to a sealing stage where a pair of hydraulic rams including heating elements effect a metallized bonding of the covers to the frame.

  18. Magnetic Resonance Online Texts

    NSDL National Science Digital Library

    S�½kora, Stanislav

    This well-organized and very thorough website was developed by the physicist Stanislav Sykora with the aim of providing free online texts, theses, and course materials on the subjects of magnetic resonance (MR), magnetic resonance imaging (MRI), nuclear-magnetic resonance (NMR) and other related topics. The amount of material on the site is impressive. At the top of the page are links to an "MR Blog", as well as to "MR Links" and the "Site Plan & SEARCH". The NMR/MRI Extras section on the right side of the page is particularly useful for visitors interested in all things about MR. Its links to "Events" provides an up-to-date list of symposia, conferences, and meetings, along with links to the events' sites. The "Societies" link offers at least 50 groups about MR, some of which are country-based, and others that are region- or application-based.

  19. Magnetostrictive resonance excitation

    DOEpatents

    Schwarz, Ricardo B. (Los Alamos, NM); Kuokkala, Veli-Tapani (Tampere, FI)

    1992-01-01

    The resonance frequency spectrum of a magnetostrictive sample is remotely determined by exciting the magnetostrictive property with an oscillating magnetic field. The permeability of a magnetostrictive material and concomitant coupling with a detection coil varies with the strain in the material whereby resonance responses of the sample can be readily detected. A suitable sample may be a magnetostrictive material or some other material having at least one side coated with a magnetostrictive material. When the sample is a suitable shape, i.e., a cube, rectangular parallelepiped, solid sphere or spherical shell, the elastic moduli or the material can be analytically determined from the measured resonance frequency spectrum. No mechanical transducers are required and the sample excitation is obtained without contact with the sample, leading to highly reproducible results and a measurement capability over a wide temperature range, e.g. from liquid nitrogen temperature to the Curie temperature of the magnetostrictive material.

  20. SOLVENT EXTRACTION OF RARE EARTHS

    Microsoft Academic Search

    I. N. Plaksin; K. F. Barysheva; A. V. Astafeva

    1962-01-01

    Descriptions are given of rare earth separation by acid leaching and ; solvent extraction with TBP. Hydrometallurgical treatment of enriched rare earth ; products enables 85 to 95% extraction into nitric acid with 50% HNOâ ; Ieaching at 80 to 904DEC. Multistaged and counter-current extraction with TBP ; separates Ca and Fe from rare earth products, extracting up to 94

  1. Active acoustic classification via transient resonance scattering

    NASA Astrophysics Data System (ADS)

    Gaunaurd, Guillermo C.

    1992-12-01

    The echoes reflected by a sound ping emerging from active sonar when it interacts with a target in its path can be remotely sensed by a receiver. The presented approach capitalizes on an air inverse scattering method that exploits the presence of certain resonance features in these echoes returned by targets to classify them. Classifying underwater objects is important to naval programs such as mine countermeasures (MC) and anti-submarine warfare (ASW) to preclude wasting of ordnance on false targets. Although the classification of complex shapes is still a formidable task, considerable progress has been made in classifying simple shapes such as spheroidal or cylindrical shells. The briefly overviewed methodology has emphasized the extraction, isolation, and labeling of resonance features hidden within the echo, but little has been said about how these could be used to classify a target. A couple of simple examples illustrate exactly how these resonances can be linked to the physical characteristics of the target, allowing for its unambiguous characterization. The procedure, although illustrated with active acoustics (i.e., sonar), can be extended to any active return from any sensor, including radar.

  2. Doubly stochastic resonance

    PubMed

    Zaikin; Kurths; Schimansky-Geier

    2000-07-10

    We report the effect of doubly stochastic resonance which appears in nonlinear extended systems if the influence of noise is twofold: A multiplicative noise induces bimodality of the mean field of the coupled network and an independent additive noise governs the dynamic behavior in response to small periodic driving. For optimally selected values of the additive noise intensity stochastic resonance is observed, which is manifested by a maximal coherence between the dynamics of the mean field and the periodic input. Numerical simulations of the signal-to-noise ratio and theoretical results from an effective two state model are in good quantitative agreement. PMID:10991250

  3. Hexagonal quartz resonator

    DOEpatents

    Peters, R.D.M.

    1982-11-02

    A generally flat, relatively thin AT-cut piezoelectric resonator element structured to minimize the force-frequency effect when mounted and energized in a housing. The resonator is in the form of an equilateral hexagon with the X crystallographic axis of the crystal passing through one set of opposing corners with mounting being effected at an adjacent set of corners respectively [+-]60[degree] away from the X axis which thereby results in a substantially zero frequency shift of the operating frequency. 3 figs.

  4. Optomechanical trampoline resonators.

    PubMed

    Kleckner, Dustin; Pepper, Brian; Jeffrey, Evan; Sonin, Petro; Thon, Susanna M; Bouwmeester, Dirk

    2011-09-26

    We report on the development of optomechanical "trampoline" resonators composed of a tiny SiO(2)/Ta(2)O(5) dielectric mirror on a silicon nitride micro-resonator. We observe optical finesses of up to 4 × 10(4) and mechanical quality factors as high as 9 × 10(5) in relatively massive (~100 ng) and low frequency (10-200 kHz) devices. This results in a photon-phonon coupling efficiency considerably higher than previous Fabry-Perot-type optomechanical systems. These devices are well suited to ultra-sensitive force detection, ground-state optical cooling experiments, and demonstrations of quantum dynamics for such systems. PMID:21996913

  5. Method for resonant measurement

    DOEpatents

    Rhodes, George W. (5201 Rio Grande Blvd., N.W., Albuquerque, NM 87107); Migliori, Albert (Rte. 4, Box 258 Tano Rd., Sante Fe, NM 87501); Dixon, Raymond D. (396 Connie Ave., White Rock, NM 87544)

    1996-01-01

    A method of measurement of objects to determine object flaws, Poisson's ratio (.sigma.) and shear modulus (.mu.) is shown and described. First, the frequency for expected degenerate responses is determined for one or more input frequencies and then splitting of degenerate resonant modes are observed to identify the presence of flaws in the object. Poisson's ratio and the shear modulus can be determined by identification of resonances dependent only on the shear modulus, and then using that shear modulus to find Poisson's ratio using other modes dependent on both the shear modulus and Poisson's ratio.

  6. Method for resonant measurement

    DOEpatents

    Rhodes, G.W.; Migliori, A.; Dixon, R.D.

    1996-03-05

    A method of measurement of objects to determine object flaws, Poisson`s ratio ({sigma}) and shear modulus ({mu}) is shown and described. First, the frequency for expected degenerate responses is determined for one or more input frequencies and then splitting of degenerate resonant modes are observed to identify the presence of flaws in the object. Poisson`s ratio and the shear modulus can be determined by identification of resonances dependent only on the shear modulus, and then using that shear modulus to find Poisson`s ratio using other modes dependent on both the shear modulus and Poisson`s ratio. 1 fig.

  7. Dynamic resonance characteristic analysis of fiber ring resonator

    NASA Astrophysics Data System (ADS)

    Ying, Diqing; Ma, Huilian; Jin, Zhonghe

    2009-01-01

    A resonator fiber optic gyro is a high accuracy inertial rotation sensor based on the Sagnac effect. Fiber ring resonator is the core-sensing element in the resonator fiber optic gyro. The dynamic response of the resonator has been studied, and the ringing phenomenon is observed when sweeping the laser frequency. The dynamic characteristics of the resonator, which are related with the frequency sweep rate, have a decisive effect on the dynamic performance of the gyro system. In order to further analyze and better design the gyro system, deep analysis of the dynamic resonance characteristics is in urgent need. This paper gives out the condition for the ringing phenomenon, and analyzes the parameters for the ringing and the dynamic resonance curve through simulation. It is concluded that increasing the sweep rate will lift the ringing and deteriorate the parameters of the resonance curve, and finally have negative effects on the performance of the gyro system.

  8. White Light Emission from Vegetable Extracts

    PubMed Central

    Singh, Vikram; Mishra, Ashok K.

    2015-01-01

    A mixture of extracts from two common vegetables, red pomegranate and turmeric, when photoexcited at 380?nm, produced almost pure white light emission (WLE) with Commission Internationale d’Eclairage (CIE) chromaticity index (0.35, 0.33) in acidic ethanol. It was also possible to obtain WLE in polyvinyl alcohol film (0.32, 0.25), and in gelatin gel (0.26, 0.33) using the same extract mixture. The colour temperature of the WLE was conveniently tunable by simply adjusting the concentrations of the component emitters. The primary emitting pigments responsible for contributing to WLE were polyphenols and anthocyanins from pomegranate, and curcumin from turmeric. It was observed that a cascade of Forster resonance energy transfer involving polyphenolics, curcumin and anthocyanins played a crucial role in obtaining a CIE index close to pure white light. The optimized methods of extraction of the two primary emitting pigments from their corresponding plant sources are simple, cheap and fairly green. PMID:26083264

  9. White Light Emission from Vegetable Extracts.

    PubMed

    Singh, Vikram; Mishra, Ashok K

    2015-01-01

    A mixture of extracts from two common vegetables, red pomegranate and turmeric, when photoexcited at 380?nm, produced almost pure white light emission (WLE) with Commission Internationale d'Eclairage (CIE) chromaticity index (0.35, 0.33) in acidic ethanol. It was also possible to obtain WLE in polyvinyl alcohol film (0.32, 0.25), and in gelatin gel (0.26, 0.33) using the same extract mixture. The colour temperature of the WLE was conveniently tunable by simply adjusting the concentrations of the component emitters. The primary emitting pigments responsible for contributing to WLE were polyphenols and anthocyanins from pomegranate, and curcumin from turmeric. It was observed that a cascade of Forster resonance energy transfer involving polyphenolics, curcumin and anthocyanins played a crucial role in obtaining a CIE index close to pure white light. The optimized methods of extraction of the two primary emitting pigments from their corresponding plant sources are simple, cheap and fairly green. PMID:26083264

  10. Ferromagnetic resonance measurements in sub-nanometer Fe films

    NASA Astrophysics Data System (ADS)

    Mizuno, Hayato; Moriyama, Takahiro; Kawaguchi, Masashi; Nagata, Masaki; Tanaka, Kensho; Koyama, Tomohiro; Chiba, Daichi; Ono, Teruo

    2015-07-01

    We show that our ferromagnetic resonance (FMR) measurement based on the rectification effect is sufficiently sensitive for characterizing various static and dynamic magnetic properties of a sub-nanometer ferromagnetic film where the interfacial effects dominate. The extracted properties, such as the Landé g-factor, the effective demagnetizing field, and the Gilbert damping parameter, are reasonably well scaled with the film thickness, indicating that our measurements clearly capture the interfacial properties of the sub-nanometer-thick film. In particular, the capability of the g-factor extraction in the ultrathin film will be very helpful for characterizing the various interfacial effects involved with interfacial orbit moments and spin–orbit interactions.

  11. Simulation and beamline experiments for the superconducting electron cyclotron resonance ion source VENUS

    SciTech Connect

    Todd, Damon S.; Leitner, Daniela; Lyneis, Claude M.; Grote, David P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2008-02-15

    The particle-in-cell code WARP has been enhanced to incorporate both two- and three-dimensional sheath extraction models giving WARP the capability of simulating entire ion beam transport systems including the extraction of beams from plasma sources. In this article, we describe a method of producing initial ion distributions for plasma extraction simulations in electron cyclotron resonance (ECR) ion sources based on experimentally measured sputtering on the source biased disk. Using this initialization method, we present preliminary results for extraction and transport simulations of an oxygen beam and compare them with experimental beam imaging on a quartz viewing plate for the superconducting ECR ion source VENUS.

  12. Coupling Extraction From Off-Shell Cross-sections

    E-print Network

    Baradhwaj Coleppa; Tanumoy Mandal; Subhadip Mitra

    2014-10-09

    In this note, we present a novel method of extracting the couplings of a new heavy particle to the Standard Model states. Contrary to the usual discovery process which involves studying the on-shell production, we look at regions away from resonance to take advantage of the simple scaling of the cross-section with the couplings. We apply the procedure to the case of a heavy quark as an illustration.

  13. Magnetic Resonance Imaging and Magnetic Resonance Spectroscopy in Dementias

    PubMed Central

    Hsu, Yuan-Yu; Du, An-Tao; Schuff, Norbert; Weiner, Michael W.

    2007-01-01

    This article reviews recent studies of magnetic resonance imaging and magnetic resonance spectroscopy in dementia, including Alzheimer's disease, frontotemporal dementia, dementia with Lewy bodies, idiopathic Parkinson's disease, Huntington's disease, and vascular dementia. Magnetic resonance imaging and magnetic resonance spectroscopy can detect structural alteration and biochemical abnormalities in the brain of demented subjects and may help in the differential diagnosis and early detection of affected individuals, monitoring disease progression, and evaluation of therapeutic effect. PMID:11563438

  14. Extraction of a single Stokes line from a Brillouin fibre laser using a silicon oxynitride microring filter

    NASA Astrophysics Data System (ADS)

    Zulkifli, M. Z.; Chong, W. Y.; Melloni, A.; Morichetti, F.; Harun, S. W.; Ahmad, H.

    2013-09-01

    Extraction of a single channel Brillouin Stokes line generated by pumping a length of single mode fibre is demonstrated using a silicon oxynitride microring resonator. The high Q-factor microring resonator has a steep slope transmission profile with an extinction ratio of 20 dB and a free spectral range of 0.4 nm. Experimental results show that extraction of a single Brillouin Stokes line can be achieved with a side mode suppression ratio of more than 12 dB. Additionally, Brillouin Stokes line selection can be achieved by controlling the microring resonance wavelength by thermal tuning.

  15. Supercritical fluid extraction

    DOEpatents

    Wai, Chien M. (Moscow, ID); Laintz, Kenneth (Pullman, WA)

    1994-01-01

    A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated or lipophilic crown ether or fluorinated dithiocarbamate. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

  16. Efficient finite-difference time-domain computation of resonant frequencies of rectangular Lamé mode resonators via a combination of the symmetry boundary conditions and the Padé approximation

    NASA Astrophysics Data System (ADS)

    Yasui, Takashi; Hasegawa, Koji; Hirayama, Koichi

    2015-07-01

    Resonant frequency analysis of the fundamental and higher-order modes of Lamé mode resonators on a lossless isotropic solid is carried out by the finite-difference time-domain (FD-TD) method with the staggered grid with collocated grid points of velocities (SGCV). The symmetry boundary condition is implemented to reduce the size of the computational domain for the FD-TD method with the SGCV. One spectrum estimation technique based on the Padé approximation is employed to effectively extract the resonant frequencies from a spectrum transformed from the time series data calculated by the FD-TD method. Numerical results show the validity and efficiency of these techniques.

  17. Nanoscale devices based on plasmonic coaxial waveguide resonators

    NASA Astrophysics Data System (ADS)

    Mahigir, A.; Dastmalchi, P.; Shin, W.; Fan, S.; Veronis, G.

    2015-02-01

    Waveguide-resonator systems are particularly useful for the development of several integrated photonic devices, such as tunable filters, optical switches, channel drop filters, reflectors, and impedance matching elements. In this paper, we introduce nanoscale devices based on plasmonic coaxial waveguide resonators. In particular, we investigate threedimensional nanostructures consisting of plasmonic coaxial stub resonators side-coupled to a plasmonic coaxial waveguide. We use coaxial waveguides with square cross sections, which can be fabricated using lithography-based techniques. The waveguides are placed on top of a silicon substrate, and the space between inner and outer coaxial metals is filled with silica. We use silver as the metal. We investigate structures consisting of a single plasmonic coaxial resonator, which is terminated either in a short or an open circuit, side-coupled to a coaxial waveguide. We show that the incident waveguide mode is almost completely reflected on resonance, while far from the resonance the waveguide mode is almost completely transmitted. We also show that the properties of the waveguide systems can be accurately described using a single-mode scattering matrix theory. The transmission and reflection coefficients at waveguide junctions are either calculated using the concept of the characteristic impedance or are directly numerically extracted using full-wave three-dimensional finite-difference frequency-domain simulations.

  18. Radiofrequency coils for magnetic resonance applications: theory, design, and evaluation.

    PubMed

    Giovannetti, Giulio; Hartwig, Valentina; Positano, Vincenzo; Vanello, Nicola

    2014-01-01

    Magnetic resonance imaging and magnetic resonance spectroscopy are noninvasive diagnostic techniques based on the phenomenon of nuclear magnetic resonance. Radiofrequency coils are key components in both the transmission and receiving phases of magnetic resonance systems. Transmitter coils have to produce a highly homogeneous alternating field in a wide field of view, whereas receiver coils have to maximize signal detection while minimizing noise. Development of modern magnetic resonance coils often is based on numerical methods for simulating and predicting coil performance. Numerical methods allows the behavior of the coil in the presence of realistic loads to be simulated and the coil's efficiency at high magnetic fields to be investigated. After being built, coils have to be characterized in the laboratory to optimize their setting and performance by extracting several quality indices. Successively, coils performance has to be evaluated in a scanner using standardized image quality parameters with phantom and human experiments. This article reviews the principles of radiofrequency coils, coil performance parameters, and their estimation methods using simulations, workbench, and magnetic resonance experiments. Finally, an overview of future developments in radiofrequency coils technology is included. PMID:25403875

  19. Axicon based conical resonators with high power copper vapor laser

    NASA Astrophysics Data System (ADS)

    Singh, Bijendra; Subramaniam, V. V.; Daultabad, S. R.; Chakraborty, Ashim

    2010-07-01

    We report for the first time the performance of axicon based conical resonators (ABCRs) in a copper vapor laser, with novel results. The unstable conical resonator comprising of conical mirror (reflecting axicon) with axicon angle ˜?/18, cone angle ˜160°, and a convex mirror of 60 cm radius of curvature was effective in reducing the average beam divergence to ˜0.15 mrad (˜25 fold reduction compared to standard multimode plane-plane cavity) with output power of ˜31 W. Extraction efficiency of ˜50%-60% and beam divergence of <1 mrad was achieved in other stable ABCR configurations using flat and concave mirrors with the axicon. This is a significant improvement compared to 4-5 mrad normally observed in conventional stable resonators in copper vapor lasers. The conical resonators with copper vapor laser provide high misalignment tolerance ? ˜4-5 mrad where ? is the tilt angle of the conical mirror from optimum position responsible for ˜20% decline in laser power. The depth of focus d was ˜three times larger in case of conical resonator as compared to that of standard spherical unstable resonator under similar beam divergence and focusing conditions.

  20. Tandem resonator reflectance modulator

    Microsoft Academic Search

    I. J. Fritz; J. R. Wendt

    1994-01-01

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and

  1. Coronary magnetic resonance angiography

    Microsoft Academic Search

    Matthias Stuber; Robert G. Weiss

    2007-01-01

    Coronary magnetic resonance angiography (MRA) is a pow- erful noninvasive technique with high soft-tissue contrast for the visualization of the coronary anatomy without X-ray exposure. Due to the small dimensions and tortuous na- ture of the coronary arteries, a high spatial resolution and sufficient volumetric coverage have to be obtained. How- ever, this necessitates scanning times that are typically much

  2. Dispersive ionospheric Alfvén resonator

    Microsoft Academic Search

    Oleg A. Pokhotelov; D. Pokhotelov; A. Streltsov; V. Khruschev; M. Parrot

    2000-01-01

    A new model of the ionospheric Alfvén resonator (IAR) including the effect of wave frequency dispersion is presented. It is shown that the shear Alfvén waves in the IAR are coupled to the compressional mode through the boundary conditions at the ionosphere. This coupling results in the appearance of the Hall dispersion and subsequent shift of the IAR frequency spectrum.

  3. RESONATOR PARTICLE SEPARATOR

    Microsoft Academic Search

    J. P. Blewett; J. D. Kiesling

    1963-01-01

    A wave-guide resonator structure is designed for use in separating ; particles of equal momentum but differing in mass, having energies exceeding one ; billion eiectron volts. The particles referred to are those of sub-atomic size ; and are generally produced as a result of the bombardment of a target by a beam ; such as protons produced in a

  4. RESONATOR PARTICLE SEPARATOR

    Microsoft Academic Search

    1962-01-01

    A wave guide resonator structure is described for use in separating ; particles of equal momentum but differing in mass and having energies exceeding ; one billion electron volts. The particles are those of sub-atomic size and are ; generally produced as a result of the bombardment of a target by a beam such as ; protons produced in a

  5. Micromachined double resonator

    NASA Technical Reports Server (NTRS)

    Gutierrez, Roman (Inventor); Tang, Tony K. (Inventor); Shcheglov, Kirill (Inventor)

    2002-01-01

    A micromachined resonator mountable to an external support structure has a proof mass coupled to a base structure by a first spring structure, the base structure having a plurality of electrodes, and a second spring structure coupling the base structure to the external support structure.

  6. Resonance Ionization, Mass Spectrometry.

    ERIC Educational Resources Information Center

    Young, J. P.; And Others

    1989-01-01

    Discussed is an analytical technique that uses photons from lasers to resonantly excite an electron from some initial state of a gaseous atom through various excited states of the atom or molecule. Described are the apparatus, some analytical applications, and the precision and accuracy of the technique. Lists 26 references. (CW)

  7. Electroexcitation of Nucleon Resonances

    SciTech Connect

    Volker Burkert

    2003-05-01

    Recent electroproduction results in the domain of s-channel mucleon resonance excitation are presented, and preliminary data in the search for missing states will be discussed. I also address a new avenue to pursue N* physics using exclusive deeply virtual Compton scattering, recently measured for the first time at Jefferson Lab and DESY.

  8. Magnetic resonance imaging

    SciTech Connect

    Stark, D.D.; Bradley, W.G. Jr.

    1988-01-01

    The authors present a review of magnetic resonance imaging. Many topics are explored from instrumentation, spectroscopy, blood flow and sodium imaging to detailed clinical applications such as the differential diagnosis of multiple sclerosis or adrenal adenoma. The emphasis throughout is on descriptions of normal multiplanar anatomy and pathology as displayed by MRI.

  9. Coherent synchro-betatron resonance

    SciTech Connect

    Burov, A.; Lebedev, V.; /Fermilab

    2006-12-01

    Coherent synchro-betatron resonances can present a serious limit for low-energy synchrotrons with strong space charge. Here, an excitation of a dipole transverse mode is considered at resonance condition.

  10. Voltage tunable microwave ferrite resonator

    E-print Network

    Oates, Daniel E.

    A novel method of implementing a tunable resonator using an applied voltage is presented. Stress is used to tune a microstrip resonator fabricated on a polycrystalline ferrite substrate. The stress was applied either ...

  11. Infrared cubic dielectric resonator metamaterial.

    SciTech Connect

    Sinclair, Michael B.; Brener, Igal; Peters, David William; Ginn, James Cleveland, III; Ten Eyck, Gregory A.

    2010-06-01

    Dielectric resonators are an effective means to realize isotropic, low-loss optical metamaterials. As proof of this concept, a cubic resonator is analytically designed and then tested in the long-wave infrared.

  12. Shape resonances in molecular fields

    NASA Astrophysics Data System (ADS)

    Dehmer, J. L.

    A shape resonance is a quasibound state in which a particle is temporarily trapped by a potential barrier (i.e., the shape of the potential), through which it may eventually tunnel and escape. This simple mechanism plays a prominent role in a variety of excitation processes in molecules, ranging from vibrational excitation by slow electrons to ionization of deep core levels by X-rays. Moreover, their localized nature makes shape resonances a close connection between shape resonances in electron-molecule scattering and in molecular photoionization. Another is the frequent persistence of free-molecule shape resonant behavior upon adsorption on a surface or condensation into a molecular solid. The basic properties of shape resonance in molecular fields are discussed. Other aspects discussed are vibrational effects of shape resonances, connections between shape resonances in different physical settings, and examples of shape resonant behavior in more complex cases, which form current challenges in this field.

  13. Analysis of Fano-line shapes from agile resonant waveguide grating sensors using correlation techniques

    NASA Astrophysics Data System (ADS)

    Bougot-Robin, K.; Wen, W. J.; Benisty, H.

    2013-05-01

    The asymmetric Fano resonance lineshape, resulting from interference between background and a resonant scattering, is archetypal in resonant waveguide grating (RWG) reflectivity. Resonant profile shift resulting from a change of refractive index (from fluid medium or biomolecules at the chip surface) is classically used to perform label-free sensing. Lineshapes are sometimes sampled at discretized "detuning" values to relax instrumental demands, the highest reflectivity element giving a coarse resonance estimate. A finer extraction, needed to increase sensor sensitivity, can be obtained using a correlation approach, correlating the sensed signal to a zero-shifted reference signal. Correlation approach is robust to asymmetry of Fano lineshapes and allows more accurate determination than usual fitting options such as Gaussian or Lorentz shape fitting. Our findings are illustrated with resonance profiles from silicon nitride "chirped" RWGs operated at visible wavelengths. The scheme circumvents the classical but demanding spectral or angular scans: instead of varying angle or wavelength through fragile moving parts or special optics, a RWG structure parameter is varied. Then, the spatial reflectivity profiles of tracks composed of RWGs units with slowly varying filling factor (thus slowly varying resonance condition) are measured under monochromatic conditions. Extracting the resonance location using plain images of these "pixelated" Fano profiles allows multiplex refractive index based sensing with a sensitivity down to 2×10-5 RIU as demonstrated experimentally. This scheme based on a "Peak-tracking chip" demonstrates a new technique for bioarray imaging using a simpler set-up that maintains high performance with cheap lenses.

  14. EXTRACTIVE METALLURGY OF EUXENITE

    Microsoft Academic Search

    S. L. May; J. L. Tews; A. W. Henderson; W. G. Gruzensky

    1959-01-01

    Results of this study demonstrate that multiple-oxide minerals can be ; processed to usable compounds by the techniques described. The chlorination ; procedure offers an efficient method for extracting tantalum, niobium, uranium, ; titanium, thorium, and the rare-earth elements from their ores. Separation of ; the chloride products into four groups is of additional benefit for processing ; materials such

  15. Solidphase extraction of phenols

    Microsoft Academic Search

    I Rodr??guez; M. P Llompart; R Cela

    2000-01-01

    Sample preparation for phenol analysis using solid-phase extraction (SPE) is reviewed. The scope of the review has been restricted to the literature dealing with the analysis of phenols as the main objective. The use, advantages and disadvantages of silica sorbents, polymeric, functionalised, carbon-based and mixed available sorbents, when applied to the separation and preconcentration of phenols, as well as the

  16. Introduction to DNA Extractions

    NSDL National Science Digital Library

    Hays, Lana

    This lab exercise, authored by Lana Hays of Access Excellence at the National Health Museum, giving instructions for the extraction of DNA from several different starting materials. The lab employs everyday material which can be found at your local grocery store. The exercise is designed for the 6-12 grade level.

  17. Resonances in Coupled ?K??K Scattering from Quantum Chromodynamics

    DOE PAGESBeta

    Dudek, Jozef J.; Edwards, Robert G.; Thomas, Christopher E.; Wilson, David J.

    2014-10-01

    Using first-principles calculation within Quantum Chromodynamics, we are able to reproduce the pattern of experimental strange resonances which appear as complex singularities within coupled ?K, ?K scattering amplitudes. We make use of numerical computation within the lattice discretized approach to QCD, extracting the energy dependence of scattering amplitudes through their relation- ship to the discrete spectrum of the theory in a finite-volume, which we map out in unprecedented detail.

  18. Microscopic nuclear form factors for the pygmy dipole resonance

    NASA Astrophysics Data System (ADS)

    Lanza, E. G.; Vitturi, A.; Andrés, M. V.

    2015-05-01

    It is shown that the use of a proper form factor in the study of the pygmy dipole resonance (PDR) is of paramount importance in order to determine the correct values for the relevant quantities characterizing these new modes. Form factors calculated within a microscopic model are compared with those provided by different macroscopic collective models. Their differences, shown in the shape and magnitude, are reflected on the calculated cross section and therefore jeopardize the extracted physical quantities.

  19. Repetitive resonant railgun power supply

    DOEpatents

    Honig, E.M.; Nunnally, W.C.

    1985-06-19

    A repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. The supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles.

  20. High frequency STW resonator filters

    Microsoft Academic Search

    R. Almar; B. Horine; J. Andersen

    1992-01-01

    The authors present results obtained in the 1-GHz-2-GHz region for surface transverse wave (STW) resonator filters implemented using inline coupled (RFI) and combined mode resonator filter (CMRF) techniques. The STW device performance is strongly dependent on the surface confinement of the acoustic wave. In an inline resonator filter the inner grating serves the dual purpose of trapping the energy near

  1. A Micromachined Tunable Cavity Resonator

    Microsoft Academic Search

    D. Mercier; M. Chatras; J. C. Orlianges; C. Champeaux; A. Catherinot; P. Blondy; D. Cros; J. Papapolymerou

    2003-01-01

    This paper focuses on a tunable resonator fabricated using bulk and surface micro-machining techniques. The resonator consists of a silicon micro-machined metalized cavity coupled with a MEMS bridge capacitor for tunability purposes. The resonator is excited using coplanar waveguide lines to avoid losses from transitions and facilitate measurements. The unloaded quality factor of the device is about 150 depending on

  2. Eigenproblems in Resonant MEMS Design

    E-print Network

    Bai, Zhaojun

    Eigenproblems in Resonant MEMS Design David Bindel UC Berkeley, CS Division Eigenproblems inResonant MEMS Design ­ p.1/21 #12;What are MEMS? Eigenproblems inResonant MEMS Design ­ p.2/21 #12;RF MEMSResonant MEMS Design ­ p.3/21 #12;Micromechanical filters Filtered signal Mechanical filter Capacitive sense

  3. Signal amplification in a nanomechanical Duffing resonator via stochastic resonance

    NASA Astrophysics Data System (ADS)

    Almog, Ronen; Zaitsev, Stav; Shtempluck, Oleg; Buks, Eyal

    2007-01-01

    The authors experimentally study stochastic resonance in a nonlinear bistable nanomechanical doubly clamped beam resonator, which is capacitively excited by an adjacent gate electrode. The resonator is tuned to its bistability region by an intense pump near a point of equal transition rates between its two metastable states. The pump is amplitude modulated, inducing modulation of the activation barrier between the states. When noise is added to the excitation, resonator's displacement exhibits noise dependent amplification of the modulation signal. They measure resonator's response in the time and frequency domains, the spectral amplification, and the statistical distribution of the jump time.

  4. Superconducting coplanar waveguide resonators for electron spin resonance applications

    NASA Astrophysics Data System (ADS)

    Sigillito, A. J.; Jock, R. M.; Tyryshkin, A. M.; Malissa, H.; Lyon, S. A.

    2013-03-01

    Superconducting coplanar waveguide (CPW) resonators are a promising alternative to conventional volume resonators for electron spin resonance (ESR) experiments where the sample volume and thus the number of spins is small. However, the magnetic fields required for ESR could present a problem for Nb superconducting resonators, which can be driven normal. Very thin Nb films (50 nm) and careful alignment of the resonators parallel to the magnetic field avoid driving the Nb normal, but flux trapping can still be an issue. Trapped flux reduces the resonator Q-factor, can lead to resonant frequency instability, and can lead to magnetic field inhomogeneities. At temperatures of 1.9 K and in a magnetic field 0.32 T, we have tested X-band resonators fabricated directly on the surface of a silicon sample. Q-factors in excess of 15,000 have been obtained. A thin layer of GE varnish applied directly to the resonator has been used to glue a sapphire wafer to its surface, and we still find Q-factors of 16,000 or more in the 0.32 T field. ESR applications of these resonators will be discussed. Superconducting coplanar waveguide (CPW) resonators are a promising alternative to conventional volume resonators for electron spin resonance (ESR) experiments where the sample volume and thus the number of spins is small. However, the magnetic fields required for ESR could present a problem for Nb superconducting resonators, which can be driven normal. Very thin Nb films (50 nm) and careful alignment of the resonators parallel to the magnetic field avoid driving the Nb normal, but flux trapping can still be an issue. Trapped flux reduces the resonator Q-factor, can lead to resonant frequency instability, and can lead to magnetic field inhomogeneities. At temperatures of 1.9 K and in a magnetic field 0.32 T, we have tested X-band resonators fabricated directly on the surface of a silicon sample. Q-factors in excess of 15,000 have been obtained. A thin layer of GE varnish applied directly to the resonator has been used to glue a sapphire wafer to its surface, and we still find Q-factors of 16,000 or more in the 0.32 T field. ESR applications of these resonators will be discussed. Supported in part by the ARO.

  5. Resonant structure of ?-->3??0?? and ?-->???? decays

    NASA Astrophysics Data System (ADS)

    Edwards, K. W.; Janicek, R.; Patel, P. M.; Sadoff, A. J.; Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Davis, R.; Kotov, S.; Kravchenko, I.; Kwak, N.; Zhao, X.; Anderson, S.; Frolov, V. V.; Kubota, Y.; Lee, S. J.; Mahapatra, R.; O'neill, J. J.; Poling, R.; Riehle, T.; Smith, A.; Ahmed, S.; Alam, M. S.; Athar, S. B.; Jian, L.; Ling, L.; Mahmood, A. H.; Saleem, M.; Timm, S.; Wappler, F.; Anastassov, A.; Duboscq, J. E.; Gan, K. K.; Gwon, C.; Hart, T.; Honscheid, K.; Kagan, H.; Kass, R.; Lorenc, J.; Schwarthoff, H.; von Toerne, E.; Zoeller, M. M.; Richichi, S. J.; Severini, H.; Skubic, P.; Undrus, A.; Bishai, M.; Chen, S.; Fast, J.; Hinson, J. W.; Lee, J.; Menon, N.; Miller, D. H.; Shibata, E. I.; Shipsey, I. P.; Kwon, Y.; Lyon, A. L.; Thorndike, E. H.; Jessop, C. P.; Lingel, K.; Marsiske, H.; Perl, M. L.; Savinov, V.; Ugolini, D.; Zhou, X.; Coan, T. E.; Fadeyev, V.; Korolkov, I.; Maravin, Y.; Narsky, I.; Shelkov, V.; Stroynowski, R.; Ye, J.; Wlodek, T.; Artuso, M.; Ayad, R.; Dambasuren, E.; Kopp, S.; Majumder, G.; Moneti, G. C.; Mountain, R.; Schuh, S.; Skwarnicki, T.; Stone, S.; Titov, A.; Viehhauser, G.; Wang, J. C.; Wolf, A.; Wu, J.; Csorna, S. E.; McLean, K. W.; Marka, S.; Xu, Z.; Godang, R.; Kinoshita, K.; Lai, I. C.; Pomianowski, P.; Schrenk, S.; Bonvicini, G.; Cinabro, D.; Greene, R.; Perera, L. P.; Zhou, G. J.; Chan, S.; Eigen, G.; Lipeles, E.; Schmidtler, M.; Shapiro, A.; Sun, W. M.; Urheim, J.; Weinstein, A. J.; Würthwein, F.; Jaffe, D. E.; Masek, G.; Paar, H. P.; Potter, E. M.; Prell, S.; Sharma, V.; Asner, D. M.; Eppich, A.; Gronberg, J.; Hill, T. S.; Lange, D. J.; Morrison, R. J.; Nelson, T. K.; Richman, J. D.; Briere, R. A.; Behrens, B. H.; Ford, W. T.; Gritsan, A.; Krieg, H.; Roy, J.; Smith, J. G.; Alexander, J. P.; Baker, R.; Bebek, C.; Berger, B. E.; Berkelman, K.; Blanc, F.; Boisvert, V.; Cassel, D. G.; Dickson, M.; Drell, P. S.; Ecklund, K. M.; Ehrlich, R.; Foland, A. D.; Gaidarev, P.; Galik, R. S.; Gibbons, L.; Gittelman, B.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Hopman, P. I.; Jones, C. D.; Kreinick, D. L.; Lee, T.; Liu, Y.; Meyer, T. O.; Mistry, N. B.; Ng, C. R.; Nordberg, E.; Patterson, J. R.; Peterson, D.; Riley, D.; Thayer, J. G.; Thies, P. G.; Valant-Spaight, B.; Warburton, A.; Avery, P.; Lohner, M.; Prescott, C.; Rubiera, A. I.; Yelton, J.; Zheng, J.; Brandenburg, G.; Ershov, A.; Gao, Y. S.; Kim, D. Y.-J.; Wilson, R.; Browder, T. E.; Li, Y.; Rodriguez, J. L.; Yamamoto, H.; Bergfeld, T.; Eisenstein, B. I.; Ernst, J.; Gladding, G. E.; Gollin, G. D.; Hans, R. M.; Johnson, E.; Karliner, I.; Marsh, M. A.; Palmer, M.; Plager, C.; Sedlack, C.; Selen, M.; Thaler, J. J.; Williams, J.

    2000-04-01

    The resonant structure of the four pion final state in the decay ?-->3??0?? has been analyzed using 4.27 million ?+?- pairs collected by the CLEO II experiment at the Cornell Electron Storage Ring. A partial wave analysis of the resonant structure of the ?-->3??0?? decay has been performed; the spectral decomposition of the four pion system is dominated by the ?? and a1? final states. The mass and width of the ?' resonance have been extracted from a fit to the ?-->???? spectral function. We have searched for second class currents in the decay ?-->???? using spin-parity analysis and established an upper limit on the non-vector current contribution.

  6. Surface-resistance measurements using superconducting stripline resonators

    SciTech Connect

    Hafner, Daniel; Dressel, Martin; Scheffler, Marc, E-mail: scheffl@pi1.physik.uni-stuttgart.de [1. Physikalisches Institut, Universität Stuttgart, D-70550 Stuttgart (Germany)] [1. Physikalisches Institut, Universität Stuttgart, D-70550 Stuttgart (Germany)

    2014-01-15

    We present a method to measure the absolute surface resistance of conductive samples at a set of GHz frequencies with superconducting lead stripline resonators at temperatures 1–6 K. The stripline structure can easily be applied for bulk samples and allows direct calculation of the surface resistance without the requirement of additional calibration measurements or sample reference points. We further describe a correction method to reduce experimental background on high-Q resonance modes by exploiting TEM-properties of the external cabling. We then show applications of this method to the reference materials gold, tantalum, and tin, which include the anomalous skin effect and conventional superconductivity. Furthermore, we extract the complex optical conductivity for an all-lead stripline resonator to find a coherence peak and the superconducting gap of lead.

  7. Cost effectiveness of magnetic resonance imaging in the neurosciences.

    PubMed Central

    Szczepura, A K; Fletcher, J; Fitz-Patrick, J D

    1991-01-01

    OBJECTIVES--To measure, in a service setting, the effect of magnetic resonance imaging on diagnosis, diagnostic certainty, and patient management in the neurosciences; to measure the cost per patient scanned; to estimate the marginal cost of imaging and compare this with its diagnostic impact; to measure changes in patients' quality of life; and to record the diagnostic pathway leading to magnetic resonance imaging. DESIGN--Controlled observational study using questionnaires on diagnosis and patient management before and after imaging. Detailed costing study. Quality of life questionnaires at the time of imaging and six months later. Diagnostic pathways extracted from medical records for a representative sample. SETTING--Regional superconducting 1.5 T magnetic resonance service. SUBJECTS--782 consecutive neuroscience patients referred by consultants for magnetic resonance imaging during June 1988-9; diagnostic pathways recorded for 158 cases. MAIN OUTCOME MEASURES--Costs of magnetic resonance imaging and preliminary investigations; changes in planned management and resulting savings; changes in principal diagnosis and diagnostic certainty; changes in patients' quality of life. RESULTS--Average cost of magnetic resonance imaging was estimated at 206.20/patient pounds (throughput 2250 patients/year, 1989-90 prices including contrast and upgrading). Before magnetic resonance imaging diagnostic procedures cost 164.40/patient pounds (including inpatient stays). Management changed after imaging in 208 (27%) cases; saving an estimated 80.90/patient pounds. Confidence in planned management increased in a further 226 (29%) referrals. Consultants' principal diagnosis changed in 159 of 782 (20%) referrals; marginal cost per diagnostic change was 626 pounds. Confidence in diagnosis increased in 236 (30%) referrals. No improvement in patients' quality of life at six month assessment. CONCLUSIONS--Any improvement in diagnosis with magnetic resonance imaging is achieved at a higher cost. Techniques for monitoring the cost effectiveness of this technology need to be developed. PMID:1819260

  8. Identification of Resonant States via the Generalized Virial Theorem

    E-print Network

    Luigi Genovese; Alessandro Cerioni; Maxime Morinière; Thierry Deutsch

    2015-04-02

    The numerical extraction of resonant states of open quantum systems is usually a difficult problem. Regularization techniques, such as the mapping to complex coordinates or the addition of Complex Absorbing Potentials are typically employed, as they render resonant wavefunctions localized and therefore normalizable. Physically relevant metastable states have energies that do not depend on the chosen regularization method. Their identification therefore involves cumbersome comparisons between multiple regularised calculations, often performed graphically, which require fine-tuning and specific intuition to avoid approximated, if not wrong, results. In this Letter, we define an operator that explicitly measures such invariance, valid for any arbitrary mapping of spatial coordinates. Resonant states of the system can eventually simply be identified evaluating the expectation value of this operator. Our method eases the extraction of resonant states even for numerical potentials that are difficult to scale to complex coordinates, and avoids the need for ad hoc complex absorbing potentials. We provide explicit evidence of our findings discussing one-dimensional case-studies,also in the presence of external electric fields.

  9. Low power laser concepts for high power laser ring resonator alignment

    Microsoft Academic Search

    D. M. Swain; G. F. Morr; D. H. Schwamb; R. E. Waldo

    1993-01-01

    The paper discusses the design features of four low-power laser (LPL) concepts (the external LPL concept, the annular LPL, the compact beam LPL, and the rear cone LPL) for use in the alignment of a high-power laser (HPL) for space applications and describes a specific high-power ring resonator, the High Extraction Decentered Annular Ring Resonator. Particular attention is given to

  10. Spectral parameters of resonance sound scattering from a circular cylindrical thin elastic shell

    Microsoft Academic Search

    O. P. Piddubniak; N. G. Piddubniak

    1999-01-01

    The resonance scattering of plane sound waves from a circular cylindrical thin elastic shell with a vacuum inside is investigated. The R-matrix method for suppression of the background contribution in the total form-function and for extraction of the spectral information (positions and widths of the spectral lines) is used. The resonance characteristics of the multipole order m=2 are analyzed in

  11. Resonant and High Magnetic Available BE

    E-print Network

    Ohta, Shigemi

    .2 resonant scattering resonant and high magneticfield scattering resonant scattering and XMCD resonant and high magneticfield scattering and XMCD BE Beamline equivalent 1 BE is a station running Footnotes: a = Resonant scattering program inactive since summer 2010 b = Resonant and high magneticfield

  12. Injection-controlled laser resonator

    DOEpatents

    Chang, Jim J. (Dublin, CA)

    1995-07-18

    A new injection-controlled laser resonator incorporates self-filtering and self-imaging characteristics with an efficient injection scheme. A low-divergence laser signal is injected into the resonator, which enables the injection signal to be converted to the desired resonator modes before the main laser pulse starts. This injection technique and resonator design enable the laser cavity to improve the quality of the injection signal through self-filtering before the main laser pulse starts. The self-imaging property of the present resonator reduces the cavity induced diffraction effects and, in turn, improves the laser beam quality.

  13. Injection-controlled laser resonator

    DOEpatents

    Chang, J.J.

    1995-07-18

    A new injection-controlled laser resonator incorporates self-filtering and self-imaging characteristics with an efficient injection scheme. A low-divergence laser signal is injected into the resonator, which enables the injection signal to be converted to the desired resonator modes before the main laser pulse starts. This injection technique and resonator design enable the laser cavity to improve the quality of the injection signal through self-filtering before the main laser pulse starts. The self-imaging property of the present resonator reduces the cavity induced diffraction effects and, in turn, improves the laser beam quality. 5 figs.

  14. Analysis of human muscle extracts by proton NMR

    SciTech Connect

    Venkatasubramanian, P.N.; Barany, M.; Arus, C.

    1986-03-01

    Perchloric acid extracts were prepared from pooled human muscle biopsies from patients diagnosed with scoliosis (SCOL) and cerebral palsy (CP). After neutralization with KOH and removal of perchlorate, the extracts were concentrated by freeze drying and dissolved in /sup 2/H/sub 2/O to contain 120 O.D. units at 280 nm per 0.5 ml. /sup 1/H NMR spectroscopy was performed with the 5 mm probe of a Varian XL300 instrument. Creatine, lactate, carnosine, and choline were the major resonances in the one-dimensional spectra of both extracts. With creatine as reference, 2.5-fold more lactate was found in SCOL than in CP, and a much smaller difference was also found in their carnosine content. Two-dimensional COSY comparison revealed several differences between the two extracts. Taurine, N-acetyl glutamate, glycerophosphoryl choline (or phosphoryl choline) and an unidentified spot were present only in the extract from SCOL but not in that from CP. On the other hand, aspartate, hydroxy-proline, carnitine and glycerophosphoryl ethanolamine were only present in CP but absent in SCOL. Alanine, cysteine, lysine and arginine appeared in both extracts without an apparent intensity difference.

  15. Effects of hot water extraction and fungal decay on wood crystalline cellulose structure

    Microsoft Academic Search

    Caitlin HowellAnne; Anne Christine Steenkjær Hastrup; Rory Jara; Flemming Hofmann Larsen; Barry Goodell; Jody Jellison

    The effect of hot-water extraction and two types of fungal decay, brown rot and white rot, on wood crystalline cellulose structure\\u000a was examined using a combination of X-ray diffraction (XRD) and 13C solid-state nuclear magnetic resonance (NMR) spectroscopy. Although having opposite effects on the overall crystallinity\\u000a of the wood, the XRD results revealed that both extraction and brown-rot decay caused

  16. Novel method for multiturn extraction: trapping charged particles in islands of phase space.

    PubMed

    Cappi, R; Giovannozzi, M

    2002-03-11

    A novel method for multiturn extraction from a circular particle accelerator is presented, based on trapping particles into islands of phase space generated by nonlinear resonances. By appropriate use of sextupoles and octupoles, stable islands can be created at small amplitude in phase space. By varying the linear tune, particles can be trapped inside these islands and then transported towards higher amplitudes for extraction. Results of numerical simulations are discussed. PMID:11909360

  17. Removal of Bioremediation Residues by Vegetable Oil Extraction and Slurry Phase Biotreatment

    Microsoft Academic Search

    Y. Xu; M. Lu; F. He; Y. Li

    2011-01-01

    Bioremediation residues in a highly petroleum-contaminated soil were characterized by Fourier transform–ion cyclotron resonance–mass spectrometry (FT-ICR-MS). Naphthenic acids (O2 species) dominated the residues. Rapeseed oil was used to extract the residues from the soil. Extraction efficiency was approximately 80% when the oil–soil (v\\/m) ratio was 2:1. Total mass removal of the residues was more than 90% when the resulting contaminated

  18. Pygmy dipole resonance

    NASA Astrophysics Data System (ADS)

    Ponomarev, Vladimir

    2014-09-01

    The pygmy dipole resonance (PDR) is a low-energy debris of the 1hslash? El-strength which is pushed by an isovector residual interaction to higher energies to form the giant dipole resonance. It exhausts about 1% of the EWSR below the particle threshold. High energy resolution experiments performed during the last decade reveal fine structure of the PDR in many nuclei. We report on the studies of the PDR fine structure performed within the Quasiparticle-Phonon model. Excited states are described by a wave function which includes one-, two-, and three-phonon configurations, i.e. the configuration space in calculations below the threshold is almost complete. We discuss also some particular features of the PDR excitation in different nuclear reactions.

  19. Photorefractivity in WGM resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Savchenkov, Anatoliy; Strekalov, Dmitry; Ilchenko, Vladimir; Maleki, Lute

    2006-01-01

    We report on observation of photorefractive effects in whispering gallery mode resonators made of as-grown and magnesium doped lithium niobate and lithium tantalate in the near as well as far infrared. The effects manifested themselves as dynamic modification of the spectra as well as quality factors of the resonators coupled to the laser radiation. We have observed a significant (exceeding 10-4) change of the ordinary index of refraction of all the materials exposed with 780 nm light. Photorefractive effects have also been detected at 1550 nm. Our experiments support the conclusion that the photorefractivity does not have a distinct red boundary. We show that the maximum saturated refractive index change in the infrared is of the same order of magnitude as in the visible light.

  20. Saw Blades and Resonance

    NASA Astrophysics Data System (ADS)

    Liebl, Michael

    2005-05-01

    This paper describes an inexpensive, classroom experiment that allows students to quantitatively investigate resonance using a hacksaw blade. The blade clamped to the edge of a table forms a cantilever that may vibrate at any of a number of preferred frequencies. A small cylindrical magnet is fixed to the saw blade. An electromagnetic coil powered by a frequency generator causes large-amplitude vibrations of the saw blade at the resonant frequencies. Vibrations of a similar system, a vibrating car antenna, have been discussed by Newburgh and Newburgh. The dramatic increases in the oscillation amplitude are both instructive and fascinating. Analogies may be drawn to systems ranging from a child on a swing to the Tacoma Narrows bridge.

  1. Energetics of stochastic resonance

    NASA Astrophysics Data System (ADS)

    Jung, Peter; Marchesoni, Fabio

    2011-12-01

    In this paper, we discuss the motion of a Brownian particle in a double-well potential driven by a periodic force in terms of energies delivered by the periodic and the noise forces and energy dissipated into the viscous environment. It is shown that, while the power delivered by the periodic force to the Brownian particle is controlled by the strength of the noise, the power delivered by the noise itself is independent of the amplitude and frequency of the periodic force. The implications of this result for the mechanism of stochastic resonance in an equilibrium system is that it is not energy from the noise force which enhances a small periodic force, but rather an increase of energy delivered by the periodic force, regulated by the strength of the noise. We further re-evaluate the frequency dependence of stochastic resonance in terms of energetic terms including efficiency.

  2. Energetics of stochastic resonance.

    PubMed

    Jung, Peter; Marchesoni, Fabio

    2011-12-01

    In this paper, we discuss the motion of a Brownian particle in a double-well potential driven by a periodic force in terms of energies delivered by the periodic and the noise forces and energy dissipated into the viscous environment. It is shown that, while the power delivered by the periodic force to the Brownian particle is controlled by the strength of the noise, the power delivered by the noise itself is independent of the amplitude and frequency of the periodic force. The implications of this result for the mechanism of stochastic resonance in an equilibrium system is that it is not energy from the noise force which enhances a small periodic force, but rather an increase of energy delivered by the periodic force, regulated by the strength of the noise. We further re-evaluate the frequency dependence of stochastic resonance in terms of energetic terms including efficiency. PMID:22225390

  3. Resonance with Stochastic Time

    NASA Astrophysics Data System (ADS)

    Ohira, Toru

    2010-06-01

    We introduce a resonant phenomenon using a model incorporating delay (temporal non-locality) and stochastic time (temporal stochasticity). Although this model is a very simple linear dynamical differential equation, the addition of these elements makes it very rich. As an illustrative example, we describe a human stick balancing experiment that includes added fluctuations. We discuss how these concepts of temporal non-locality and stochasticity could play a role in characterizing biological and physiological systems, as well as in physics.

  4. Cross resonant optical antenna.

    PubMed

    Biagioni, P; Huang, J S; Duò, L; Finazzi, M; Hecht, B

    2009-06-26

    We propose a novel cross resonant optical antenna consisting of two perpendicular nanosized gold dipole antennas with a common feed gap. We demonstrate that the cross antenna is able to convert propagating fields of any polarization state into correspondingly polarized, localized, and enhanced fields and vice versa. The cross antenna structure therefore opens the road towards the control of light-matter interactions based on polarized light as well as the analysis of polarized fields on the nanometer scale. PMID:19659107

  5. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, Ian J. (Albuquerque, NM); Wendt, Joel R. (Albuquerque, NM)

    1994-01-01

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors.

  6. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, I.J.; Wendt, J.R.

    1994-09-06

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors. 8 figs.

  7. Magnetic resonance imaging methodology

    Microsoft Academic Search

    Ewald Moser; Andreas Stadlbauer; Christian Windischberger; Harald H. Quick; Mark E. Ladd

    2009-01-01

    Introduction  Magnetic resonance (MR) methods are non-invasive techniques to provide detailed, multi-parametric information on human anatomy,\\u000a function and metabolism. Sensitivity, specificity, spatial and temporal resolution may, however, vary depending on hardware\\u000a (e.g., field strength, gradient strength and speed) and software (optimised measurement protocols and parameters for the various\\u000a techniques). Furthermore, multi-modality imaging may enhance specificity to better characterise complex disease patterns.

  8. Magnetic resonance urography

    Microsoft Academic Search

    John R. Leyendecker; John W. Gianini

    2009-01-01

    Excellent contrast resolution and lack of ionizing radiation make magnetic resonance urography (MRU) a promising technique\\u000a for noninvasively evaluating the entire urinary tract. While MRU currently lags behind CT urography (CTU) in spatial resolution\\u000a and efficiency, new hardware and sequence developments have contributed to a resurgence of interest in MRU techniques. By\\u000a combining unenhanced sequences with multiphase contrast-enhanced and excretory

  9. Solid phase extraction membrane

    DOEpatents

    Carlson, Kurt C [Nashville, TN; Langer, Roger L [Hudson, WI

    2002-11-05

    A wet-laid, porous solid phase extraction sheet material that contains both active particles and binder and that possesses excellent wet strength is described. The binder is present in a relatively small amount while the particles are present in a relatively large amount. The sheet material is sufficiently strong and flexible so as to be pleatable so that, for example, it can be used in a cartridge device.

  10. Extraction of gamma

    E-print Network

    Robert Fleischer

    2001-10-22

    After a brief look at the well-known standard approaches to determine the angle gamma of the unitarity triangle, we focus on two kinds of strategies, employing $B\\to\\pi K$ modes, and U-spin-related B decays. Interesting "puzzles", which may already be indicated by the present B-factory data, are pointed out, and the importance of the extraction of hadronic parameters, which are provided by these strategies as by-products, is emphasized.

  11. [Skeleton extractions and applications].

    SciTech Connect

    Quadros, William Roshan

    2010-05-01

    This paper focuses on the extraction of skeletons of CAD models and its applications in finite element (FE) mesh generation. The term 'skeleton of a CAD model' can be visualized as analogous to the 'skeleton of a human body'. The skeletal representations covered in this paper include medial axis transform (MAT), Voronoi diagram (VD), chordal axis transform (CAT), mid surface, digital skeletons, and disconnected skeletons. In the literature, the properties of a skeleton have been utilized in developing various algorithms for extracting skeletons. Three main approaches include: (1) the bisection method where the skeleton exists at equidistant from at least two points on boundary, (2) the grassfire propagation method in which the skeleton exists where the opposing fronts meet, and (3) the duality method where the skeleton is a dual of the object. In the last decade, the author has applied different skeletal representations in all-quad meshing, hex meshing, mid-surface meshing, mesh size function generation, defeaturing, and decomposition. A brief discussion on the related work from other researchers in the area of tri meshing, tet meshing, and anisotropic meshing is also included. This paper concludes by summarizing the strengths and weaknesses of the skeleton-based approaches in solving various geometry-centered problems in FE mesh generation. The skeletons have proved to be a great shape abstraction tool in analyzing the geometric complexity of CAD models as they are symmetric, simpler (reduced dimension), and provide local thickness information. However, skeletons generally require some cleanup, and stability and sensitivity of the skeletons should be controlled during extraction. Also, selecting a suitable application-specific skeleton and a computationally efficient method of extraction is critical.

  12. Resonant non-gaussianity

    SciTech Connect

    Flauger, Raphael [Department of Physics, Yale University, New Haven, CT 06520 (United States); Pajer, Enrico, E-mail: raphael.flauger@yale.edu, E-mail: ep295@cornell.edu [Department of Physics, Cornell University, Ithaca, NY 14853 (United States)

    2011-01-01

    We provide a derivation from first principles of the primordial bispectrum of scalar perturbations produced during inflation driven by a canonically normalized scalar field whose potential exhibits small sinusoidal modulations. A potential of this type has been derived in a class of string theory models of inflation based on axion monodromy. We use this model as a concrete example, but we present our derivations and results for a general slow-roll potential with superimposed modulations. We show analytically that a resonance between the oscillations of the background and the oscillations of the fluctuations is responsible for the production of an observably large non-Gaussian signal. We provide an explicit expression for the shape of this resonant non-Gaussianity. We show that there is essentially no overlap between this shape and the local, equilateral, and orthogonal shapes, and we stress that resonant non-Gaussianity is not captured by the simplest version of the effective field theory of inflation. We hope our analytic expression will be useful to further observationally constrain this class of models.

  13. Gravito-electromagnetic resonances

    E-print Network

    Christos G. Tsagas

    2011-08-10

    The interaction between gravitational and electromagnetic radiation has a rather long research history. It is well known, in particular, that gravity-wave distortions can drive propagating electromagnetic signals. Since forced oscillations provide the natural stage for resonances to occur, gravito-electromagnetic resonances have been investigated as a means of more efficient gravity-wave detection methods. In this report, we consider the coupling between the Weyl and the Maxwell fields on a Minkowski background, which also applies to astrophysical environments where gravity is weak, at the second perturbative level. We use covariant methods that describe gravitational waves via the transverse component of the shear, instead of pure-tensor metric perturbations. The aim is to calculate the properties of the electromagnetic signal, which emerges from the interaction of its linear counterpart with an incoming gravitational wave. Our analysis shows how the wavelength and the amplitude of the gravitationally driven electromagnetic wave vary with the initial conditions. More specifically, for certain initial data, the amplitude of the induced electromagnetic signal is found to diverge. Analogous, diverging, gravito-electromagnetic resonances were also reported in cosmology. Given that, we extend our Minkowski-space study to cosmology and discuss analogies and differences in the physics and in the phenomenology of the Weyl-Maxwell coupling between the aforementioned two physical environments.

  14. Bactericidal activity of herbal extracts

    Microsoft Academic Search

    Nikolaus Thuille; Manfred Fille; Markus Nagl

    2003-01-01

    The antimicrobial activity of total herbal extracts has been investigated. The MIC of extracts of Evodia rutaecarpa and grape kernel ranged between 0.25 and 1 mg\\/ml against gram-positive cocci and P. aeruginosa. Cocci were killed after 30 – 90 min of incubation in grape kernel extract (0.5 – 1.5 mg\\/ml), and after 8 h in evodia extract (0.5 – 1

  15. Extraction chemistry of some bidentate organophosphorus compounds

    Microsoft Academic Search

    L. L. Martella; J. D. Navratil; W. F. Santiago

    1978-01-01

    The extraction chemistry of methylenediphosphonates, carbamoylphosphonates, and carbamoylmethylenephosphonates has been investigated. The bidentate organophosphorus compounds extract actinides strongly, extract lanthanides, iron, gallium, molybdenum, titanium, vanadium, and zirconium partially, and do not extract most other elements from 5 to 7 M nitric acid. The properties of the extractants and extraction mechanisms are discussed. The effect of complexing agents on the extraction

  16. 659.5-nm high-power solid state laser with a two-rod telescope resonator

    NASA Astrophysics Data System (ADS)

    Wu, Shouyue; Chen, Baizhong; Yu, Ge

    2014-12-01

    A two-rod V-type telescope resonator is proposed to obtain the single-frequency 659.5nm high power red laser output with possessing the advantages of both the flat-flat symmetrical resonator and telescope resonator. This resonator extracts the pumping power by equalizing the fundamental mode volumes to the greatest extent possible at the tandem two rods. Simultaneously, it aggrandizes the SHG (second-harmonic generation) efficiency by sharply compressing the spot size in the relatively independent focus cavity. In the experiment, the red laser power reaches 63.1W under total 1000W LD pumping power.

  17. Detection and identification of underwater targets by resonance or resonant scattering

    Microsoft Academic Search

    Gee-In Goo

    1997-01-01

    This paper presents the resonance or resonant scattering technique for detection and identification of underwater targets. Based on the resonance theory and the resonant scattering theory (RST), all underwater objects resonate at their natural frequencies when impinged by acoustic energy. These resonating natural frequencies appear as modulations on the frequency domain of the target echoes. Since these natural resonances are

  18. Resonant tunneling IR detectors

    NASA Technical Reports Server (NTRS)

    Woodall, Jerry M.; Smith, T. P., III

    1990-01-01

    Researchers propose a novel semiconductor heterojunction photodetector which would have a very low dark current and would be voltage tunable. A schematic diagram of the device and its band structure are shown. The two crucial components of the device are a cathode (InGaAs) whose condition band edge is below the conduction band edge of the quantum wells and a resonant tunneling filter (GaAs-AlGaAs). In a standard resonant tunneling device the electrodes are made of the same material as the quantum wells, and this device becomes highly conducting when the quantum levels in the wells are aligned with the Fermi level in the negatively biased electrode. In contrast, the researchers device is essentially non-conducting under the same bias conditions. This is because the Fermi Level of the cathode (InGaAs) is still well below the quantum levels so that no resonant transport occurs and the barriers (AlGaAs) effectively block current flow through the device. However, if light with the same photon energy as the conduction-band discontinuity between the cathode and the quantum wells, E sub c3-E sub c1, is shone on the sample, free carriers will be excited to an energy corresponding to the lowest quantum level in the well closest to the cathode (hv plue E sub c1 = E sub o). These electrons will resonantly tunnel through the quantum wells and be collected as a photocurrent in the anode (GaAs). To improve the quantum efficiency, the cathode (InGaAs) should be very heavily doped and capped with a highly reflective metal ohmic contact. The thickness of the device should be tailored to optimize thin film interference effects and afford the maximum absorption of light. Because the device relies on resonant tunneling, its response should be very fast, and the small voltages needed to change the responsivity should allow for very high frequency modulation of the photocurrent. In addition, the device is tuned to a specific photon energy so that it can be designed to detect a fairly narrow range of wavelengths. This selectivity is important for reducing the photocurrent due to spurious light sources.

  19. Joint Inference in Information Extraction

    Microsoft Academic Search

    Hoifung Poon; Pedro Domingos

    2007-01-01

    The goal of information extraction is to extract database records from text or semi-structured sources. Traditionally, information extraction proceeds by first segmenting each can- didate record separately, and then merging records that refer to the same entities. While computationally efficient, this ap- proach is suboptimal, because it ignores the fact that segment- ing one candidate record can help to segment

  20. All-optical clock recovery from 40 Gbit/s RZ signal based on microring resonators.

    PubMed

    Xiong, Meng; Ding, Yunhong; Zhang, Qiang; Zhang, Xinliang

    2011-10-01

    A scheme for high-speed clock recovery from return-to-zero (RZ) signal with microring resonators is presented. By using a silicon microring resonator (MRR) for clock extraction and a 3-order nonlinear series-coupled microring resonator (SCMR) for amplitude equalization, clock pulses with amplitude modulation less than 1 dB can be obtained. The proposed scheme is also designed and numerically studied by 3D full vectorial film mode matching method (FMM) and coupled mode theory (CMT). Simulation results show that clock can be recovered at 40 Gbit/s with short rise- and fall- times. PMID:22016205

  1. Chemical oxygen-iodine laser power generation with an off-axis hybrid resonator.

    PubMed

    Handke, Jürgen; Schall, Wolfgang O; Hall, Thomas; Duschek, Frank; Grünewald, Karin M

    2006-06-01

    A rectangular negative branch off-axis hybrid resonator was coupled to a 10 kW class chemical oxygen-iodine laser. Resonator setup and alignment turned out to be straightforward. The extracted power was 6.6 kW and reached approximately 70% of the power for an optimized stable resonator. The divergence of the emitted laser beam in the unstable direction was lower than two times the diffraction limit. Experimentally measured margins for mirror misalignment were found in close agreement with numerical calculations. PMID:16724146

  2. Tunable resonant and non-resonant interactions between a phase qubit and LC resonator

    NASA Astrophysics Data System (ADS)

    Allman, Michael Shane; Whittaker, Jed D.; Castellanos-Beltran, Manuel; Cicak, Katarina; da Silva, Fabio; Defeo, Michael; Lecocq, Florent; Sirois, Adam; Teufel, John; Aumentado, Jose; Simmonds, Raymond W.

    2014-03-01

    We use a flux-biased radio frequency superconducting quantum interference device (rf SQUID) with an embedded flux-biased direct current (dc) SQUID to generate strong resonant and non-resonant tunable interactions between a phase qubit and a lumped-element resonator. The rf-SQUID creates a tunable magnetic susceptibility between the qubit and resonator providing resonant coupling rates from zero to near the ultra-strong coupling regime. By modulating the magnetic susceptibility, non-resonant parametric coupling achieves rates > 100 MHz . Nonlinearity of the magnetic susceptibility also leads to parametric coupling at subharmonics of the qubit-resonator detuning. Controllable coupling is generically important for constructing coupled-mode systems ubiquitous in physics, useful for both, quantum information architectures and quantum simulators. This work supported by NIST and NSA grant EAO140639.

  3. Proton Spin Structure in the Resonance Region

    SciTech Connect

    Wesselmann, F. R. [University of Virginia, Charlottesville, Virginia 22903 (United States); Norfolk State University, Norfolk, Virginia 23504 (United States); Slifer, K.; Tajima, S.; Crabb, D.; Day, D.; Frlez, E.; Lindgren, R.; McKee, P.; McNulty, D.; Norum, B.; Pocanic, D.; Prok, Y.; Rondon, O. A.; Sawatzky, B.; Smith, C.; Wang, K.; Zeier, M.; Zhu, H. [University of Virginia, Charlottesville, Virginia 22903 (United States); Aghalaryan, A.; Asaturyan, R. [Yerevan Physics Institute, Yerevan (Armenia)] (and others)

    2007-03-30

    We have examined the spin structure of the proton in the region of the nucleon resonances (1.085 GeVextracted the asymmetries A{sub 1} and A{sub 2}, and the spin structure functions g{sub 1} and g{sub 2}. We found a notably nonzero A{sub perpendicular}, significant contributions from higher-twist effects, and only weak support for polarized quark-hadron duality.

  4. Charmonium resonances and Fano line shapes

    E-print Network

    Xu Cao; H. Lenske

    2014-08-24

    Anomalous line shapes of quarkonia are explained naturally as an interference effect of a $c\\bar c$ confined closed channel with the surrounding continua, well established in other fields of physics as Fano-resonances. We discuss a quark model coupled-channel analysis describing quarkonium as a mixing of closed $Q\\bar Q$ and molecular-like $D\\bar D$ open channels. The asymmetric line shapes observed in $\\psi(3770)$ production cross sections in $e^+e^-$ annihilation to $D^0\\bar{D}^0$ and $D^+ D^-$, respectively, are described very well. The method allows to extract directly from the data the amount of $Q\\bar Q \\leftrightarrow D\\bar D$ configuration mixing.

  5. Fast Resonator Depopulation with a Simple Measurement Pulse Shape

    NASA Astrophysics Data System (ADS)

    McClure, Douglas; Paik, Hanhee; Bishop, Lev S.; Gambetta, Jay; Steffen, Matthias; Chow, Jerry

    2015-03-01

    Recent innovations have enabled fast, accurate qubit readout in the circuit QED architecture, but often it is also important to quickly return the readout resonator to its ground state afterward: any residual photons continue to measure and Stark-shift the qubit, preventing high-fidelity gates. Simply waiting several times the resonator decay constant is inadequate for multi-qubit operations in which some qubits need to be measured and reused while others remain in superpositions, which would lose coherence during this time. Here we demonstrate fast, qubit-state-independent resonator reset using a readout pulse with a simple piecewise-constant envelope. The pulse differs from a square pulse only by the addition of two segments at the end, whose width and amplitude depend on the resonator linewidth and qubit-resonator coupling strength. To quantify the effectiveness of the pulse at resetting the cavity, we extract the residual photon population using a Ramsey experiment performed shortly after the pulse. Comparing the result to that obtained using a square pulse followed by a delay of the same length as the extra segments, we find that the extra segments shorten the total wait time needed to recover high qubit coherence by about 300 ns, more than twice the cavity time constant. We acknowledge support from IARPA under Contract W911NF-10-1-0324.

  6. Pediatric Brain Extraction Using Learning-based Meta-algorithm

    PubMed Central

    Shi, Feng; Wang, Li; Dai, Yakang; Gilmore, John H.; Lin, Weili; Shen, Dinggang

    2012-01-01

    Magnetic resonance imaging of pediatric brain provides valuable information for early brain development studies. Automated brain extraction is challenging due to the small brain size and dynamic change of tissue contrast in the developing brains. In this paper, we propose a novel Learning Algorithm for Brain Extraction and Labeling (LABEL) specially for the pediatric MR brain images. The idea is to perform multiple complementary brain extractions on a given testing image by using a meta-algorithm, including BET and BSE, where the parameters of each run of the meta-algorithm are effectively learned from the training data. Also, the representative subjects are selected as exemplars and used to guide brain extraction of new subjects in different age groups. We further develop a level-set based fusion method to combine multiple brain extractions together with a closed smooth surface for obtaining the final extraction. The proposed method has been extensively evaluated in subjects of three representative age groups, such as neonate (less than 2 months), infant (1–2 years), and child (5–18 years). Experimental results show that, with 45 subjects for training (15 neonates, 15 infant, and 15 children), the proposed method can produce more accurate brain extraction results on 246 testing subjects (75 neonates, 126 infants, and 45 children), i.e., at average Jaccard Index of 0.953, compared to those by BET (0.918), BSE (0.902), ROBEX (0.901), GCUT (0.856), and other fusion methods such as Majority Voting (0.919) and STAPLE (0.941). Along with the largely-improved computational efficiency, the proposed method demonstrates its ability of automated brain extraction for pediatric MR images in a large age range. PMID:22634859

  7. Extracting Tag Hierarchies

    PubMed Central

    Tibély, Gergely; Pollner, Péter; Vicsek, Tamás; Palla, Gergely

    2013-01-01

    Tagging items with descriptive annotations or keywords is a very natural way to compress and highlight information about the properties of the given entity. Over the years several methods have been proposed for extracting a hierarchy between the tags for systems with a "flat", egalitarian organization of the tags, which is very common when the tags correspond to free words given by numerous independent people. Here we present a complete framework for automated tag hierarchy extraction based on tag occurrence statistics. Along with proposing new algorithms, we are also introducing different quality measures enabling the detailed comparison of competing approaches from different aspects. Furthermore, we set up a synthetic, computer generated benchmark providing a versatile tool for testing, with a couple of tunable parameters capable of generating a wide range of test beds. Beside the computer generated input we also use real data in our studies, including a biological example with a pre-defined hierarchy between the tags. The encouraging similarity between the pre-defined and reconstructed hierarchy, as well as the seemingly meaningful hierarchies obtained for other real systems indicate that tag hierarchy extraction is a very promising direction for further research with a great potential for practical applications. Tags have become very prevalent nowadays in various online platforms ranging from blogs through scientific publications to protein databases. Furthermore, tagging systems dedicated for voluntary tagging of photos, films, books, etc. with free words are also becoming popular. The emerging large collections of tags associated with different objects are often referred to as folksonomies, highlighting their collaborative origin and the “flat” organization of the tags opposed to traditional hierarchical categorization. Adding a tag hierarchy corresponding to a given folksonomy can very effectively help narrowing or broadening the scope of search. Moreover, recommendation systems could also benefit from a tag hierarchy. PMID:24391901

  8. Optical resonator and laser applications

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, Shervin (Inventor); Vanzyl, Jakob J. (Inventor); Yariv, Amnon (Inventor)

    2006-01-01

    The invention discloses a semi-ring Fabry-Perot (SRFP) optical resonator structure comprising a medium including an edge forming a reflective facet and a waveguide within the medium, the waveguide having opposing ends formed by the reflective facet. The performance of the SRFP resonator can be further enhanced by including a Mach-Zehnder interferometer in the waveguide on one side of the gain medium. The optical resonator can be employed in a variety of optical devices. Laser structures using at least one SRFP resonator are disclosed where the resonators are disposed on opposite sides of a gain medium. Other laser structures employing one or more resonators on one side of a gain region are also disclosed.

  9. Cavity Optomechanics with Graphene Resonators

    NASA Astrophysics Data System (ADS)

    Barton, Robert; Storch, Isaac; Adiga, Vivekananda; Sakakibara, Reyu; Wang, Si Ping; Ong, Peijie; Ilic, B.; McEuen, Paul; Parpia, Jeevak; Craighead, Harold

    2012-02-01

    Optical manipulation of micromechanical and nanomechanical resonators promises control of quantum states of macroscopic systems, among other applications. Because the spring constant of a resonator scales with its mass, there are advantages associated with using the lightest possible membranes as the mechanical elements. Here, we demonstrate that graphene, a one-atom-thick membrane, can be used as the mechanically active part of an optomechanical system. We show that a laser coupled to a Fabry-Perot cavity between a graphene resonator and a reflective backplane can both enhance and damp graphene motion. The enhancement of resonator motion is sufficient to induce self-oscillation, which is useful for applications in sensing and signal processing. These experiments demonstrate that graphene resonators are useful for optomechanical applications and show promise for resonator cooling toward the quantum ground state.

  10. Laser resonators with tilted reflectors.

    PubMed

    Sanderson, R L; Streifer, W

    1969-11-01

    In this paper we solve the mode problem for laser resonators having identical tilted spherical reflectors of rectangular shape in both stable and unstable configurations. Gaussian quadrature integration is employed to convert the integral equation for the modes into a matrix equation which is solved with the matrix diagonalization program ALLMAT. Plane parallel and aligned concentric resonators have identical losses; however, the latter are shown to be much less sensitive to alignment. We find that for low loss modes in the tilted stable resonator the loss can be approximated by the average loss of two aligned resonators; the region of validity for this approximation is given. Stable resonator losses increase monotonically with tilt; however, this is not always true for the unstable resonator where the loss may decrease for small tilts. PMID:20076006

  11. Fermi resonance in optical microcavities.

    PubMed

    Yi, Chang-Hwan; Yu, Hyeon-Hye; Lee, Ji-Won; Kim, Chil-Min

    2015-04-01

    Fermi resonance is a phenomenon of quantum mechanical superposition, which most often occurs between normal and overtone modes in molecular systems that are nearly coincident in energy. We find that scarred resonances in deformed dielectric microcavities are the very phenomenon of Fermi resonance, that is, a pair of quasinormal modes interact with each other due to coupling and a pair of resonances are generated through an avoided resonance crossing. Then the quantum number difference of a pair of quasinormal modes, which is a consequence of quantum mechanical superposition, equals periodic orbits, whereby the resonances are localized on the periodic orbits. We derive the relation between the quantum number difference and the periodic orbits and confirm it in an elliptic, a rectangular, and a stadium-shaped dielectric microcavity. PMID:25974558

  12. DISSIPATIVE DIVERGENCE OF RESONANT ORBITS

    SciTech Connect

    Batygin, Konstantin [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Morbidelli, Alessandro, E-mail: kbatygin@gps.caltech.edu [Departement Cassiopee, Universite de Nice-Sophia Antipolis, Observatoire de la Cote d'Azur, F-06304 Nice (France)

    2013-01-01

    A considerable fraction of multi-planet systems discovered by the observational surveys of extrasolar planets reside in mild proximity to first-order mean-motion resonances. However, the relative remoteness of such systems from nominal resonant period ratios (e.g., 2:1, 3:2, and 4:3) has been interpreted as evidence for lack of resonant interactions. Here, we show that a slow divergence away from exact commensurability is a natural outcome of dissipative evolution and demonstrate that libration of critical angles can be maintained tens of percent away from nominal resonance. We construct an analytical theory for the long-term dynamical evolution of dissipated resonant planetary pairs and confirm our calculations numerically. Collectively, our results suggest that a significant fraction of the near-commensurate extrasolar planets are in fact resonant and have undergone significant dissipative evolution.

  13. Coal extraction - environmental prediction

    SciTech Connect

    C. Blaine Cecil; Susan J. Tewalt

    2002-08-01

    To predict and help minimize the impact of coal extraction in the Appalachian region, the U.S. Geological Survey (USGS) is addressing selected mine-drainage issues through the following four interrelated studies: spatial variability of deleterious materials in coal and coal-bearing strata; kinetics of pyrite oxidation; improved spatial geologic models of the potential for drainage from abandoned coal mines; and methodologies for the remediation of waters discharged from coal mines. As these goals are achieved, the recovery of coal resources will be enhanced. 2 figs.

  14. Structure of hyperon resonances

    SciTech Connect

    Umino, Y.

    1992-01-01

    Baryons are composite objects. Although this fact has been verified beyond doubt, the authors are far from understanding its internal structure using first principles based on Quantum Chromodynamics (QCD). This theory of strong interactions governs the dynamics of quarks and gluons with which the authors ultimately would like to describe nuclear physics. Any realistic model of baryons should therefore simulate QCD and somehow make connections to nuclear physics. In this work, the authors use a candidate for one such model, the chiral bag model, to examine whether it can offer any valuable insights into the structure of hyperon resonances, especially those that might play important roles in hypernuclear physics. The authors begin by calculating the mass spectrum of negative parity hyperons in this model calculation are discussed and an estimate is made of the magnitude of theoretical uncertainty in the results. After exploring how the masses and the spin-flavor compositions of the hyperon resonances are determined, the authors find a reasonable fit to the mass spectrum. However, a comparison with another model prediction indicates that this alone is insufficient to determine the structure of excited hyperons. Therefore, the authors calculate some strong interaction properties and radiative decay widths of the two lightest hyperon resonances. Both of these quantities are sensitive to the spin-flavor composition of the hyperons and the former are of interest to low energy KN interactions while the latter also test model dependent electromagnetic transition operators. The authors also comment on the complicated structure of the [Lambda](1405) and argue that experimental determination of hyperon radiative widths would provide an ideal probe to explore the structure of excited strange baryons.

  15. Antimicrobial Efficacy of Henna Extracts

    PubMed Central

    Al-Rubiay, Kathem K.; Jaber, Nawres N; Alrubaiy, Laith K.

    2008-01-01

    Lawsonia inermis (henna plant) has been used in herbal medicine for ages. However, the medical benefits of this plant have been discussed in only a few publications. In this study, the antibacterial effects of water, alcoholic and oily extracts of Lawsonia inermis leaves against bacterial cultures isolated from various skin diseases were investigated and compared with Tetracycline, Ampicillin, Gentamicin and Ciprofloxacin antibiotics. Cultures of Staphylococcus aureus Staphylococcus epidermidis (Co-agulase negative staphylococci or CONS), ß-hemolytic streptococci and Pseudomonas aeruginosa species were obtained from 74 (35 females, 39 males) patients with different skin infections who attended the Dermatology outpatient clinic in Basra General Hospital. The bacterial isolates were treated with L. inermis extracts in vitro. Alcoholic and oily extracts were more effective than the water extract which had no effects using standard method of NCCL, 2000. Alcoholic extracts had the highest antibacterial activity with a MIC of 0.125-0.150 µg/ml against ß-hemolytic streptococci and against CONS was 0.125-175 µg/ml .Oily extracts had a MIC of 0.25-0.30 µg/ml against Staphylococcus epidermidis (cons). Both alcoholic and oily extracts had the same MIC (0.5 µg/ml) on Staphylococcus aureus. However, alcoholic extracts were more effective on Pseudomonas aeruginosa with a MIC of 0.5-0.57 µg/ml than oily extract (MIC of 0.20-0.28 µg/ml). However, there were no statically differences between the effects of oily and alcoholic henna extracts (p= 0.050). When comparing the extracts’ MICs with those of antibiotics, alcoholic extracts showed pronounced antibacterial effects against the isolated bacteria in vitro but oily extracts had much similar MICs to those of antibiotics and there are significant difference between effect of both extracts and antibiotics p>0.050. PMID:22334837

  16. Breast magnetic resonance imaging.

    PubMed

    Johnson, Marlene M

    2012-01-01

    Mammography has long been considered the gold standard for screening breast cancer. Although it reduces the risk of breast cancer mortality by enabling early diagnosis, it does not detect all breast cancers. Numerous breast imaging technologies are emerging as effective adjunctive diagnostic tools when mammography results are negative or inconclusive. Contrast-enhanced magnetic resonance (CE-MR) imaging, in particular, has demonstrated a high sensitivity and has proven to be most effective, especially with patients at high risk for developing breast cancer. This article discusses the clinical applications for breast MR imaging, use of CE-MR for breast cancer detection, and other emerging breast imaging technologies. PMID:22267704

  17. Resonance test system

    DOEpatents

    Musial, Walter (Boulder, CO); White, Darris (Superior, CO)

    2011-05-31

    An apparatus (10) for applying at least one load to a specimen (12) according to one embodiment of the invention may comprise a mass (18). An actuator (20) mounted to the specimen (12) and operatively associated with the mass (18) moves the mass (18) along a linear displacement path (22) that is perpendicular to a longitudinal axis of the specimen (12). A control system (26) operatively associated with the actuator (20) operates the actuator (20) to reciprocate the mass (18) along the linear displacement path (22) at a reciprocating frequency, the reciprocating frequency being about equal to a resonance frequency of the specimen (12) in a test configuration.

  18. Nuclear Magnetic Resonance Gyroscope

    NASA Astrophysics Data System (ADS)

    Larsen, Michael

    2011-05-01

    The navigation grade micro Nuclear Magnetic Resonance Gyroscope (micro-NMRG) being developed by the Northrop Grumman Corporation is currently in phase 4 of the DARPA Navigation Grade Integrated Micro Gyro (NGIMG) program. The micro-NMRG technology is pushing the boundaries of size, weight, power, and performance allowing new small platform applications of navigation grade Inertial Navigation System (INS) technology. Information on the historical development of the technology, basics of operation, task performance goals, application opportunities, and a phase 2 sample of earth rate measurement data will be presented. Funding Provided by the Defense Advanced Research Projects Agency (DARPA)

  19. Nuclear magnetic resonance spectroscopy

    SciTech Connect

    Harris, R.K.

    1986-01-01

    NMR is remarkable in the number of innovations that have appeared and become established within the past five years. This thoroughly up-to-date account of the field explains fundamentals and applications of the NMR phenomenon from the viewpoint of a physical chemist. Beginning with descriptions of basic concepts involved in continuous wave operation, the book goes on to cover spectral analysis, relaxation phenomena, the effects of pulses, the Fourier transform model, double resonance and the effects of chemical exchange and quadrupolar interactions. The book also includes the new techniques for work on solids and for complicated pulse sequences, plus abundant figures and illustrative spectra.

  20. Mercury's resonant rotation from secular orbital elements

    E-print Network

    Stark, Alexander; Hussmann, Hauke

    2015-01-01

    We used recently produced Solar System ephemeris, which incorporate two years of ranging observations to the MESSENGER spacecraft, to extract the secular orbital elements for Mercury and associated uncertainties. As Mercury is in a stable 3:2 spin-orbit resonance these values constitute an important reference for the planet's measured rotational parameters, which in turn strongly bear on physical interpretation of Mercury's interior structure. In particular, we derive an mean orbital period of 87.96934962 $\\pm$ 0.00000037 days and (assuming the perfect resonance) a spin rate of 6.138506839 $\\pm$ 0.000000028 degree/day. The difference between this rotation rate and the currently adopted rotation rate (Archinal et al, 2011) corresponds to a longitudinal displacement of approx. 67 m per year at the equator. Moreover, we present a basic approach for the calculation of the orientation of the instantaneous Laplace and Cassini planes of Mercury. The analysis allows us to assess the uncertainties in physical paramete...

  1. Coupled resonator vertical cavity laser

    SciTech Connect

    Choquette, K.D.; Chow, W.W.; Hou, H.Q.; Geib, K.M.; Hammons, B.E.

    1998-01-01

    The monolithic integration of coupled resonators within a vertical cavity laser opens up new possibilities due to the unique ability to tailor the interaction between the cavities. The authors report the first electrically injected coupled resonator vertical-cavity laser diode and demonstrate novel characteristics arising from the cavity coupling, including methods for external modulation of the laser. A coupled mode theory is used model the output modulation of the coupled resonator vertical cavity laser.

  2. GAUSSIAN BEAM LASER RESONATOR PROGRAM

    NASA Technical Reports Server (NTRS)

    Cross, P. L.

    1994-01-01

    In designing a laser cavity, the laser engineer is frequently concerned with more than the stability of the resonator. Other considerations include the size of the beam at various optical surfaces within the resonator or the performance of intracavity line-narrowing or other optical elements. Laser resonators obey the laws of Gaussian beam propagation, not geometric optics. The Gaussian Beam Laser Resonator Program models laser resonators using Gaussian ray trace techniques. It can be used to determine the propagation of radiation through laser resonators. The algorithm used in the Gaussian Beam Resonator program has three major components. First, the ray transfer matrix for the laser resonator must be calculated. Next calculations of the initial beam parameters, specifically, the beam stability, the beam waist size and location for the resonator input element, and the wavefront curvature and beam radius at the input surface to the first resonator element are performed. Finally the propagation of the beam through the optical elements is computed. The optical elements can be modeled as parallel plates, lenses, mirrors, dummy surfaces, or Gradient Index (GRIN) lenses. A Gradient Index lens is a good approximation of a laser rod operating under a thermal load. The optical system may contain up to 50 elements. In addition to the internal beam elements the optical system may contain elements external to the resonator. The Gaussian Beam Resonator program was written in Microsoft FORTRAN (Version 4.01). It was developed for the IBM PS/2 80-071 microcomputer and has been implemented on an IBM PC compatible under MS DOS 3.21. The program was developed in 1988 and requires approximately 95K bytes to operate.

  3. CMOS-based resonant sensors

    Microsoft Academic Search

    Oliver Brand

    2005-01-01

    The paper provides an overview of resonant sensors based on CMOS technology. Applications of these sensors range from inertial sensors to chemical\\/biochemical sensors, from atomic force microscopy to high-frequency filters. CMOS technology enables to co-integrate the resonant microstructures with necessary analog and digital circuit functions. The paper discusses CMOS-based fabrication approaches for resonant sensors, possible sensing and actuation schemes, suitable

  4. COMMISSIONING RESULTS OF SLOW EXTRACTION OF HEAVY IONS FROM THE AGS BOOSTER.

    SciTech Connect

    Brown, K A; Bellavia, S; Binello, S; Brelsford, B; Dumont, D; Eng, W; Gardner, G; Gassner, D; Glenn, J W; Hammons, L; Hock, J; Hoff, L; Hutchinson, E; Jamilkowski, J; Kling, N; Kotlyar, Y; Krishock, A; Lockey, R; Mapes, M; Marneris, I; Marr, G; McNerney, A; Meyer, A; Morris, J; Naylor, C; Nemesure, S; Phillips, D; Rusek, A; Ryan, J; Shrey, T; Snydstrup, L; Tsoupas, N; Vankuik, B; Zahariou-Cohen, K

    2003-05-12

    Brookhaven's AGS Booster has been modified to deliver slow extracted beam to a new beam line, the NASA Space Radiation Laboratory (NSRL). This facility was constructed in collaboration with NASA for the purpose of performing radiation effect studies for the NASA space program. The design of the resonant extraction system has been described in [1]. A more detailed description, which includes predictions of the slow extracted beam time structure has been described in [2]. In this report we will present results of the system commissioning and performance.

  5. Fast-extraction modulators for Los Alamos Scientific LaboratorY Proton Storage Ring

    SciTech Connect

    Nunnally, W.C.; Hudgings, D.W.; Sarjeant, W.J.

    1980-01-01

    The development of a short-bunch mode fast-extraction modulator for the LASL proton storage ring has made necessary the design and development of a resonant transformer charging circuit and the design of a new FIB line circuit to provide bipolar pulse outputs with low prepulse, postpulse, and an optimum high-voltage switch environments. The systems are now being developed to operate reliably at the high-average powers required. The short-bunch mode fast-extraction modulator prototype is presently operating. The initial construction of the long-bunch mode fast-extraction modulator prototype is under way, with results expected within the year.

  6. Orbital resonances around black holes.

    PubMed

    Brink, Jeandrew; Geyer, Marisa; Hinderer, Tanja

    2015-02-27

    We compute the length and time scales associated with resonant orbits around Kerr black holes for all orbital and spin parameters. Resonance-induced effects are potentially observable when the Event Horizon Telescope resolves the inner structure of Sgr A*, when space-based gravitational wave detectors record phase shifts in the waveform during the resonant passage of a compact object spiraling into the black hole, or in the frequencies of quasiperiodic oscillations for accreting black holes. The onset of geodesic chaos for non-Kerr spacetimes should occur at the resonance locations quantified here. PMID:25768747

  7. Fano resonances in nanoscale structures

    SciTech Connect

    Miroshnichenko, Andrey E.; Flach, Sergej; Kivshar, Yuri S. [Nonlinear Physics Centre and Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Max-Planck-Institut fuer Physik Komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden (Germany); Nonlinear Physics Centre and Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

    2010-07-15

    Modern nanotechnology allows one to scale down various important devices (sensors, chips, fibers, etc.) and thus opens up new horizons for their applications. The efficiency of most of them is based on fundamental physical phenomena, such as transport of wave excitations and resonances. Short propagation distances make phase-coherent processes of waves important. Often the scattering of waves involves propagation along different paths and, as a consequence, results in interference phenomena, where constructive interference corresponds to resonant enhancement and destructive interference to resonant suppression of the transmission. Recently, a variety of experimental and theoretical work has revealed such patterns in different physical settings. The purpose of this review is to relate resonant scattering to Fano resonances, known from atomic physics. One of the main features of the Fano resonance is its asymmetric line profile. The asymmetry originates from a close coexistence of resonant transmission and resonant reflection and can be reduced to the interaction of a discrete (localized) state with a continuum of propagation modes. The basic concepts of Fano resonances are introduced, their geometrical and/or dynamical origin are explained, and theoretical and experimental studies of light propagation in photonic devices, charge transport through quantum dots, plasmon scattering in Josephson-junction networks, and matter-wave scattering in ultracold atom systems, among others are reviewed.

  8. Does Geometric Coupling Generates Resonances?

    E-print Network

    I. C. Jardim; G. Alencar; R. R. Landim; R. N. Costa Filho

    2015-05-08

    Geometrical coupling in a co-dimensional one Randall-Sundrum scenario (RS) is used to study resonances of $p-$form fields. The resonances are calculated using the transfer matrix method. The model studied consider the standard RS with delta-like branes, and branes generated by kinks and domain-wall as well. The parameters are changed to control the thickness of the smooth brane. With this a very interesting pattern is found for the resonances. The geometrical coupling does not generate resonances for the reduced $p-$form in all cases considered.

  9. Electromagnetic production of hyperon resonances

    E-print Network

    K. Hicks; D. Keller; W. Tang

    2010-12-14

    The study of hyperon resonances has entered a new era of precision with advent of high-statistics photoproduction data from the CLAS detector at Jefferson Lab. These data have multi-particle final states, allowing clean identification of exclusive reactions associated with strange mesons and baryons. Examples of physics results are: evidence for isospin interference in the decay of the $\\Lambda(1405)$ resonance; a strong suggestion of meson cloud effects in the structure of the $\\Sigma(1385)$ resonance; data from $K^*$ photoproduction that will test the existence of the purported $K_0(800)$ meson. Properties of other hyperon resonances will also be studied in the near future.

  10. New approach to resonance crossing.

    PubMed

    Franchetti, G; Zimmermann, F

    2012-12-01

    Time-varying nonlinear oscillatory systems produce phenomena of resonance crossing and trapping of particles in resonance islands. Traditionally, such processes have been analyzed in terms of adiabatic conditions. Considering, as an example, a simplified one-dimensional model describing the "electron-cloud pinch" during a bunch passage in a particle accelerator, here we present an approach to resonance trapping which does not require any adiabatic condition. Instead we introduce the concept of the attraction point and investigate invariance and scaling properties of motion close to the attraction point, considering a single resonance crossing. PMID:23368210

  11. SPATIAL AND FREQUENCY DEPENDENCIES OF LOCAL PHOTORESPONSE OF HTS STRIP-LINE RESONATOR IN THE REGIME OF TWO-TONE MICROWAVE

    E-print Network

    Anlage, Steven

    SPATIAL AND FREQUENCY DEPENDENCIES OF LOCAL PHOTORESPONSE OF HTS STRIP-LINE RESONATOR IN THE REGIME resonators. The approach is based on frequency and spatial uniqueness of LSM images that can be extracted) response with respect to pumping power. This manifests itself as global intermodulation product distortion

  12. Magnetic pulsed extraction of highly charged ions from a plateau ECRIS

    Microsoft Academic Search

    L. Müller; A. Heinen; H. W. Ortjohann; H. J. Andrä

    2002-01-01

    The afterglow is known to produce pulses of highly charged ions suited for injection to accelerator facilities. We tested a new technique of magnetic pulsed extraction (PUMAEX) in our plateau-ECR ion source PECRIS III. This source has a large resonance volume due to a homogeneous magnetic field in its center. Compared to the afterglow of PECRIS III we reached higher

  13. Steps and Bumps: Precision Extraction of Discrete States of Molecular Max A. Little,

    E-print Network

    Berry, Richard

    of discrete states observed using advanced experimental techniques such as Fo¨rster resonance energy transfer College London, London, United Kingdom ABSTRACT We report statistical time-series analysis tools providingSteps and Bumps: Precision Extraction of Discrete States of Molecular Machines Max A. Little

  14. Resonance analysis of ^147Sm(n,alpha ) cross sections: Comparison to statistical model calculations and possible indications of non-statistical effects

    Microsoft Academic Search

    P. E. Koehler; Yu. M. Gledenov; T. Rauscher; C. Fröhlich

    2003-01-01

    We have measured the ^147Sm(n,alpha ) cross section from 3 eV to 500 keV and performed an R-matrix analysis in the resolved region (E_n< 700 eV) to extract alpha widths for 104 resonances. We compare the resulting resonance parameters to nuclear statistical model calculations. Comparing average resonance parameters rather than cross sections allows more direct tests of potentials used in

  15. Ion cyclotron resonance cell

    DOEpatents

    Weller, R.R.

    1995-02-14

    An ion cyclotron resonance cell is disclosed having two adjacent sections separated by a center trapping plate. The first section is defined by the center trapping plate, a first end trapping plate, and excitation and detector electrodes. The second section includes a second end trapping plate spaced apart from the center plate, a mirror, and an analyzer. The analyzer includes a wavelength-selective light detector, such as a detector incorporating an acousto-optical device (AOD) and a photodetector. One or more ion guides, grounded plates with holes for the ion beam, are positioned within the vacuum chamber of the mass spectrometer between the ion source and the cell. After ions are trapped and analyzed by ion cyclotron resonance techniques in the first section, the ions of interest are selected according to their mass and passed into the second section for optical spectroscopic studies. The trapped ions are excited by light from a laser and caused thereby to fluoresce. The fluorescent light emitted by the excited ions is reflected by the mirror and directed onto the detector. The AOD is scanned, and the photodetector output is recorded and analyzed. The ions remain in the second section for an extended period, enabling multiple studies to be carried out on the same ensemble of ions. 5 figs.

  16. Ion cyclotron resonance cell

    DOEpatents

    Weller, Robert R. (Aiken, SC)

    1995-01-01

    An ion cyclotron resonance cell having two adjacent sections separated by a center trapping plate. The first section is defined by the center trapping plate, a first end trapping plate, and excitation and detector electrodes. The second section includes a second end trapping plate spaced apart from the center plate, a mirror, and an analyzer. The analyzer includes a wavelength-selective light detector, such as a detector incorporating an acousto-optical device (AOD) and a photodetector. One or more ion guides, grounded plates with holes for the ion beam, are positioned within the vacuum chamber of the mass spectrometer between the ion source and the cell. After ions are trapped and analyzed by ion cyclotron resonance techniques in the first section, the ions of interest are selected according to their mass and passed into the second section for optical spectroscopic studies. The trapped ions are excited by light from a laser and caused thereby to fluoresce. The fluorescent light emitted by the excited ions is reflected by the mirror and directed onto the detector. The AOD is scanned, and the photodetector output is recorded and analyzed. The ions remain in the second section for an extended period, enabling multiple studies to be carried out on the same ensemble of ions.

  17. Nuclear Magnetic Resonance Gyroscope

    NASA Astrophysics Data System (ADS)

    Larsen, Michael; Griffith, Robert; Bulatowicz, Michael

    2014-03-01

    The navigation grade micro Nuclear Magnetic Resonance Gyroscope (micro-NMRG) being developed by the Northrop Grumman Corporation (NGC) has concluded the fourth and final phase of the DARPA Navigation Grade Integrated Micro Gyro (NGIMG) program. Traditional MEMS gyros utilize springs as an inherent part of the sensing mechanism, leading to bias and scale factor sensitivity to acceleration and vibration. As a result, they have not met performance expectations in real world environments and to date have been limited to tactical grade applications. The Nuclear Magnetic Resonance Gyroscope (NMRG) utilizes the fixed precession rate of a nuclear spin in a constant magnetic field as an inertial reference for determining rotation. The nuclear spin precession rate sensitivity to acceleration and vibration is negligible for most applications. Therefore, the application of new micro and batch fabrication methods to NMRG technology holds great promise for navigation grade performance in a low cost and compact gyro. This presentation will describe the operational principles, design basics, and demonstrated performance of the NMRG including an overview of the NGC designs developed and demonstrated in the DARPA gyro development program.

  18. nuclear magnetic resonance gyroscope

    SciTech Connect

    Karwacki, F. A.; Griffin, J.

    1985-04-02

    A nuclear magnetic resonance gyroscope which derives angular rotation thereof from the phases of precessing nuclear moments utilizes a single-resonance cell situated in the center of a uniform DC magnetic field. The field is generated by current flow through a circular array of coils between parallel plates. It also utilizes a pump and read-out beam and associated electronics for signal processing and control. Encapsulated in the cell for sensing rotation are odd isotopes of Mercury Hg/sup 199/ and Hg/sup 201/. Unpolarized intensity modulated light from a pump lamp is directed by lenses to a linear polarizer, quarter wave plate combination producing circularly polarized light. The circularly polarized light is reflected by a mirror to the cell transverse to the field for optical pumping of the isotopes. Unpolarized light from a readout lamp is directed by lenses to another linear polarizer. The linearly polarized light is reflected by another mirror to the cell transverse to the field and orthogonal to the pump lamp light. The linear light after transversing the cell strikes an analyzer where it is converted to an intensity-modulated light. The modulated light is detected by a photodiode processed and utilized as feedback to control the field and pump lamp excitation and readout of angular displacement.

  19. TE10 resonant iris with angular alignment

    E-print Network

    Bornemann, Jens

    TE10 resonant iris with angular alignment TE101 mode cavities TM110 mode cavities TE01 (TE10) resonant iris 1a 1b Fig. 1: Filter configurations utilizing cavity and iris resonances. Resonant irises and resonant irises. Two different configurations, which allow precise control of the direct couplings between

  20. The Ether Extract and the Chloroform Extract of Soils.

    E-print Network

    Fraps, G. S.; Rather, J. B.

    1913-01-01

    I39-3I3-5m TEXAS AGRICULTURAL EXPERIMENT STATIONS BULLETIN NO. 155 JANUARY, 1913 DIVISION OF CHEMISTRY TECHNICAL BULLETIN THE ETHER EXTRACT AND THE CHLORO? FORM EXTRACT OF SOILS BY G. S. FRAPS and J. B. RATHER POSTOFFICE COLLEGE STATION... postal card will bring these publications. THE ETHER EXTRACT AND THE CHLOROFORM EXTRACT OF SOILS. (t. S. FliAPS , Chemist. ?J. B. o Y . C U G O Assistant Chemist. The soil may coDtarn any of the Substances which are found in plants or animals...

  1. Resonance lock and planetary dynamics

    NASA Astrophysics Data System (ADS)

    Haghighipour, Nader

    1999-11-01

    The main purpose of this study is to utilize the method of partial averaging in order to analyze the dynamics of a planetary system while captured in resonance. A restricted planar circular three-body system, consisting of a star and two planets, is studied as a simple model for a planetary system. The mass of the inner planet is considered to be larger and the system is assumed to be moving in a freely rotating uniform interplanetary medium with constant density. Numerical integrations of this system indicate a resonance capture when the dynamical friction of the interplanetary medium is taken into account. As a result of this resonance trapping, the ratio of orbital periods of the two planets becomes nearly commensurable and the eccentricity and semimajor axis of the osculating orbit of the outer planet and also its angular momentum and total energy become constant. It appears from the numerical work that the resulting commensurability and also the resonant values of the orbital elements of the outer planet are essentially independent of the initial relative positions of the two bodies. In order to analytically explain this resonance phenomenon, the method of partial averaging near a resonance is utilized and the dynamics of the partially averaged system at resonance is studied. The finding that resonance lock occurs for all initial relative positions of the two planets is confirmed by analyzing the dynamics of the first order partially averaged system at resonance. It is also shown in this study that the first- order partially averaged system at resonance does not provide a complete picture of the evolutionary dynamics of the system and the similarity between the dynamical behavior of the averaged system and the main planetary system holds only for short time intervals. To overcome these limitations, the method of partial averaging near a resonance is extended to the second order of perturbation and a complete picture of the dynamical behavior of the system at resonance is presented. It is shown that the dynamics of the second-order partially averaged system at resonance resembles the dynamical evolution of the main system during the resonance lock in general. Analytical explanations for the evolution of the orbital elements of the main system while captured in resonance are also presented.

  2. Tunable dynamic Fano resonances in coupled-resonant optical waveguide

    E-print Network

    Longhi, Stefano

    2015-01-01

    A route toward lineshape engineering of Fano resonances in photonic structures is theoretically proposed, which uses dynamic modulation of the refractive index of a microcavity. The method is exemplified by considering coupled-resonator optical waveguide systems. An exact Floquet analysis, based on coupled-mode theory, is presented. Two distinct kinds of resonances can be dynamically created, depending on whether the static structure sustains a localized mode or not. In the former case a single Fano resonance arises, which can be tuned in both frequency and line width by varying the refractive index modulation amplitude and frequency. In the latter case two resonances, in the form of narrow asymmetric dips in the transmittance, are found, which can overlap resulting in an electromagnetically-induced transparency effect.

  3. Tunable dynamic Fano resonances in coupled-resonant optical waveguide

    E-print Network

    Stefano Longhi

    2015-05-15

    A route toward lineshape engineering of Fano resonances in photonic structures is theoretically proposed, which uses dynamic modulation of the refractive index of a microcavity. The method is exemplified by considering coupled-resonator optical waveguide systems. An exact Floquet analysis, based on coupled-mode theory, is presented. Two distinct kinds of resonances can be dynamically created, depending on whether the static structure sustains a localized mode or not. In the former case a single Fano resonance arises, which can be tuned in both frequency and line width by varying the refractive index modulation amplitude and frequency. In the latter case two resonances, in the form of narrow asymmetric dips in the transmittance, are found, which can overlap resulting in an electromagnetically-induced transparency effect.

  4. Electric Oxygen-Iodine Laser Performance Enhancement using Larger Discharge and Resonator Mode Volumes

    E-print Network

    Carroll, David L.

    Electric Oxygen-Iodine Laser Performance Enhancement using Larger Discharge and Resonator Mode transition of atomic iodine for only a 50% increase in gain length (5.1 cm to 7.6 cm), flow rates that significantly higher power was available in the electric oxygen-iodine laser gas flow which could be extracted

  5. Array enhanced logical stochastic resonance in the presence of delta correlated noise

    Microsoft Academic Search

    Lei Zhang; Yanchang Xiao; Xiangping Wu

    2011-01-01

    In the presence of noise floor, we investigate the logical stochastic resonance phenomenon in a parallel array consisting of bistable devices, which is driven by various cycling combinations of logic inputs. The probability of the correct logic output is calculated according to true table of logic relationships. In contrast with a single system, the significant logic response can be extracted

  6. Magnetic resonance detects metabolic changes associated with chemotherapy-induced apoptosis

    Microsoft Academic Search

    S M Ronen; F DiStefano; C L McCoy; D Robertson; T A D Smith; N M Al-Saffar; J Titley; D C Cunningham; J R Griffiths; M O Leach; P A Clarke

    1999-01-01

    Apoptosis was induced by treating L1210 leukaemia cells with mechlorethamine, and SW620 colorectal cells with doxorubicin. The onset and progression of apoptosis were monitored by assessing caspase activation, mitochondrial transmembrane potential, phosphatidylserine externalization, DNA fragmentation and cell morphology. In parallel, 31P magnetic resonance (MR) spectra of cell extracts were recorded. In L1210 cells, caspase activation was detected at 4 h.

  7. Comparison of isobaric analog resonance experiments with unified model calculations for N = 83 nuclei

    Microsoft Academic Search

    H. Clement; G. Graw

    1975-01-01

    The 01+ and 21+ parentage expansion of excited states in 139Ba, 141Ce and 145Sm has been determined via the analysis of the elastic and inelastic scattering of polarized protons in the energy region of their analog resonances. The extracted spectroscopic information indicates that present unified model calculations give a considerable overestimate of the strength of characteristic configurations in the weak

  8. Visualizing Resonances in the Complex Plane with Vibrational Phase Contrast Coherent Anti-Stokes Raman Scattering

    Microsoft Academic Search

    Martin Jurna; Erik T. Garbacik; Jeroen P. Korterik; Jennifer L. Herek; Cees Otto; Herman L. Offerhaus

    2010-01-01

    In coherent anti-Stokes Raman scattering (CARS), the emitted signal carries both amplitude and phase information of the molecules in the focal volume. Most CARS experiments ignore the phase component, but its detection allows for two advantages over intensity-only CARS. First, the pure resonant response can be determined, and the nonresonant background rejected, by extracting the imaginary component of the complex

  9. Periodic orbit analysis of molecular vibrational spectra: 1:1 resonant coupled modes

    E-print Network

    Periodic orbit analysis of molecular vibrational spectra: 1:1 resonant coupled modes Daniel C of states for a model molecular vibrational Hamiltonian describing two coupled anharmonic Morse oscillators. Periods of classical periodic orbits as a function of energy and coupling parameter are extracted directly

  10. Automated extraction of nested sulcus features from human brain MRI data.

    PubMed

    Bao, Forrest Sheng; Giard, Joachim; Tourville, Jason; Klein, Arno

    2012-01-01

    Extracting objects related to a fold in the cerebral cortex ("sulcus features") from human brain magnetic resonance imaging data has applications in morphometry, landmark-based registration, and anatomical labeling. In prior work, sulcus features such as surfaces, fundi and pits have been extracted separately. Here we define and extract nested sulcus features in a hierarchical manner from a cortical surface mesh having curvature or depth values. Our experimental results show that the nested features are comparable to features extracted separately using other methods, and that they are consistent across subjects and with manual label boundaries. Our open source feature extraction software will be made freely available as part of the Mindboggle project (http://www.mindboggle.info). PMID:23366910

  11. Double-Grating Displacement Structure for Improving the Light Extraction Efficiency of LEDs

    PubMed Central

    Wang, Zhibin; Hao, Yang; Wang, Zhongdong; Liu, Xian; Zhang, Qian; Zhu, Dandan

    2012-01-01

    To improve the light extraction efficiency of light-emitting diodes (LEDs), grating patterns were etched on GaN and silver film surfaces. The grating-patterned surface etching enabled the establishment of an LED model with a double-grating displacement structure that is based on the surface plasmon resonance principle. A numerical simulation was conducted using the finite difference time domain method. The influence of different grating periods for GaN surface and silver film thickness on light extraction efficiency was analyzed. The light extraction efficiency of LEDs was highest when the grating period satisfied grating coupling conditions. The wavelength of the highest value was also close to the light wavelength of the medium. The plasmon resonance frequencies on both sides of the silver film were affected by silver film thickness. With increasing film thickness, plasmon resonance frequency tended toward the same value and light extraction efficiency reached its maximum. When the grating period for the GaN surface was 365 nm and the silver film thickness was 390 nm, light extraction efficiency reached a maximum of 55%. PMID:23118613

  12. Impurity Extraction by Droplets

    NASA Technical Reports Server (NTRS)

    Morrison, G.; Kincaid, J. M.

    1985-01-01

    The goals are to model and to measure the phase equilibrium properties of a finely divided fluid containing a large number of chemically similar species. The objective is to develop an accurate, usable model for such phenomena as pollutant extraction of rain clouds, industrial separation in spray towers, and separation in emulsions. The project was designed as a hierarchy of complementary theoretical and experimental steps. A theory was developed to describe the segregation of complex impurities at the interface of a solvent. This phenomenon is important in phase behavior when a large fraction of molecules in a material are near an interface, the situation in a finely divided material. The theory will be modified to account for the effect of surface curvature on the surface tension. The study of mixtures differs from pure fluids not only because of the surface effects but also because composition differences between the droplet and the surrounding vapor can stabilize a droplet with respect to a bulk phase.

  13. Adaptive feature extraction expert

    SciTech Connect

    Yuschik, M.

    1983-01-01

    The identification of discriminatory features places an upper bound on the recognition rate of any automatic speech recognition (ASR) system. One way to structure the extraction of features is to construct an expert system which applies a set of rules to identify particular properties of the speech patterns. However, these patterns vary for an individual speaker and from speaker to speaker so that another expert is actually needed to learn the new variations. The author investigates the problem by using sets of discriminatory features that are suggested by a feature generation expert, improves the selectivity of these features with a training expert, and finally develops a minimally spanning feature set with a statistical selection expert. 12 references.

  14. Actinide extraction methods

    DOEpatents

    Peterman, Dean R. (Idaho Falls, ID) [Idaho Falls, ID; Klaehn, John R. (Idaho Falls, ID) [Idaho Falls, ID; Harrup, Mason K. (Idaho Falls, ID) [Idaho Falls, ID; Tillotson, Richard D. (Moore, ID) [Moore, ID; Law, Jack D. (Pocatello, ID) [Pocatello, ID

    2010-09-21

    Methods of separating actinides from lanthanides are disclosed. A regio-specific/stereo-specific dithiophosphinic acid having organic moieties is provided in an organic solvent that is then contacted with an acidic medium containing an actinide and a lanthanide. The method can extend to separating actinides from one another. Actinides are extracted as a complex with the dithiophosphinic acid. Separation compositions include an aqueous phase, an organic phase, dithiophosphinic acid, and at least one actinide. The compositions may include additional actinides and/or lanthanides. A method of producing a dithiophosphinic acid comprising at least two organic moieties selected from aromatics and alkyls, each moiety having at least one functional group is also disclosed. A source of sulfur is reacted with a halophosphine. An ammonium salt of the dithiophosphinic acid product is precipitated out of the reaction mixture. The precipitated salt is dissolved in ether. The ether is removed to yield the dithiophosphinic acid.

  15. Ethanol production by extractive fermentation

    Microsoft Academic Search

    M. Minier; G. Goma

    1982-01-01

    The ideal method to produce a terminal metabolite inhibitor of cell growth and production is to remove and recover it from the fermenting broth as it is formed. Extractive fermentation is achieved in the case of ethanol production by coupling both fermentation and liquid-liquid extraction. The solvent of extraction is 1-dodecanol (or a mixture 1-dodecanol, 1-tetradecanol); study of the inhibitory

  16. Automatic breast border extraction

    NASA Astrophysics Data System (ADS)

    Olsen, Christina M.

    2005-04-01

    In computer aided mammography algorithms there are several processing steps, which must be performed. The basic segmentation procedure involves extracting the principal feature on a mammogram; the breast border. This is performed by segmenting the breast and the non-breast into distinct regions. In this paper, a method for extracting the breast border is proposed. The method has performance similar to established techniques but with higher degrees of automatization and robustness. It iteratively adapts a model of the background to ensure a robust object detection yielding a smooth outline of the breast. The main idea is to identify the "knee" in the cumulative intensity histogram of the image. The intensity value at the knee is thereafter used to automatically define a region, to be modelled by a two-dimensional polynomial surface of degree two. The modelled background is then subtracted from the original image. The procedure described is iteratively performed until the degree of non-uniformity of the grey-scale background is smaller then a certain value. Thereafter the difference image is post-processed by a flood-filling algorithm, a new threshold is estimated as above and applied to yield a binary image. Lastly morphological operations are performed to smoothen the breast border. In conclusion, the strength in the proposed method, compared to similar methods, is that it makes use of an iterative approach to reduce the effects of the background, it produces smooth edges and automatically finds thresholds. It is also evaluated on the entire MIAS database (322 images) with a performance of 94%.

  17. Multi-frequency resonant antenna

    NASA Technical Reports Server (NTRS)

    Temps, A. J., Jr.; Visscher, J.

    1970-01-01

    Antenna is simultaneously resonant at 8.75 MHz, 11.825 MHz, and 20.562 MHz. It provides a near-field radiator which has a constant current distribution across its radiating elements for each of the resonant frequencies.

  18. Electromechanical Resonators from Graphene Sheets

    Microsoft Academic Search

    J. Scott Bunch; Arend M. Van der Zande; Scott S. Verbridge; Ian W. Frank; David M. Tanenbaum; Jeevak M. Parpia; Harold G. Craighead; Paul L. McEuen

    2007-01-01

    Nanoelectromechanical systems were fabricated from single- and multilayer graphene sheets by mechanically exfoliating thin sheets from graphite over trenches in silicon oxide. Vibrations with fundamental resonant frequencies in the megahertz range are actuated either optically or electrically and detected optically by interferometry. We demonstrate room-temperature charge sensitivities down to 8 × 10–4 electrons per root hertz. The thinnest resonator consists

  19. Analytical Treatment of Planetary Resonances

    E-print Network

    Konstantin Batygin; Alessandro Morbidelli

    2013-05-28

    An ever-growing observational aggregate of extrasolar planets has revealed that systems of planets that reside in or near mean-motion resonances are relatively common. While the origin of such systems is attributed to protoplanetary disk-driven migration, a qualitative description of the dynamical evolution of resonant planets remains largely elusive. Aided by the pioneering works of the last century, we formulate an approximate, integrable theory for first-order resonant motion. We utilize the developed theory to construct an intuitive, geometrical representation of resonances within the context of the unrestricted three-body problem. Moreover, we derive a simple analytical criterion for the appearance of secondary resonances between resonant and secular motion. Subsequently, we demonstrate the onset of rapid chaotic motion as a result of overlap among neighboring first-order mean-motion resonances, as well as the appearance of slow chaos as a result of secular modulation of the planetary orbits. Finally, we take advantage of the integrable theory to analytically show that, in the adiabatic regime, divergent encounters with first-order mean-motion resonances always lead to persistent apsidal anti-alignment.

  20. Scattering resonances as viscosity limits

    E-print Network

    Maciej Zworski

    2015-05-04

    Using the method of complex scaling we show that scattering resonances of $ - \\Delta + V $, $ V \\in L^\\infty_{\\rm{c}} ( \\mathbb R^n ) $, are limits of eigenvalues of $ - \\Delta + V - i \\epsilon x^2 $ as $ \\epsilon \\to 0+ $. That justifies a method proposed in computational chemistry and reflects a general principle for resonances in other settings.

  1. Resonating feathers produce courtship song.

    PubMed

    Bostwick, Kimberly S; Elias, Damian O; Mason, Andrew; Montealegre-Z, Fernando

    2010-03-22

    Male Club-winged Manakins, Machaeropterus deliciosus (Aves: Pipridae), produce a sustained tonal sound with specialized wing feathers. The fundamental frequency of the sound produced in nature is approximately 1500 Hz and is hypothesized to result from excitation of resonance in the feathers' hypertrophied shafts. We used laser Doppler vibrometry to determine the resonant properties of male Club-winged Manakin's wing feathers, as well as those of two unspecialized manakin species. The modified wing feathers exhibit a response peak near 1500 Hz, and unusually high Q-values (a measure of resonant tuning) for biological objects (Q up to 27). The unmodified wing feathers of the Club-winged Manakin do not exhibit strong resonant properties when measured in isolation. However, when measured still attached to the modified feathers (nine feathers held adjacent by an intact ligament), they resonate together as a unit near 1500 Hz, and the wing produces a second harmonic of similar or greater amplitude than the fundamental. The feathers of the control species also exhibit resonant peaks around 1500 Hz, but these are significantly weaker, the wing does not resonate as a unit and no harmonics are produced. These results lend critical support to the resonant stridulation hypothesis of sound production in M. deliciosus. PMID:19906670

  2. Passive vapor extraction feasibility study

    SciTech Connect

    Rohay, V.J.

    1994-06-30

    Demonstration of a passive vapor extraction remediation system is planned for sites in the 200 West Area used in the past for the disposal of waste liquids containing carbon tetrachloride. The passive vapor extraction units will consist of a 4-in.-diameter pipe, a check valve, a canister filled with granular activated carbon, and a wind turbine. The check valve will prevent inflow of air that otherwise would dilute the soil gas and make its subsequent extraction less efficient. The granular activated carbon is used to adsorb the carbon tetrachloride from the air. The wind turbine enhances extraction rates on windy days. Passive vapor extraction units will be designed and operated to meet all applicable or relevant and appropriate requirements. Based on a cost analysis, passive vapor extraction was found to be a cost-effective method for remediation of soils containing lower concentrations of volatile contaminants. Passive vapor extraction used on wells that average 10-stdft{sup 3}/min air flow rates was found to be more cost effective than active vapor extraction for concentrations below 500 parts per million by volume (ppm) of carbon tetrachloride. For wells that average 5-stdft{sup 3}/min air flow rates, passive vapor extraction is more cost effective below 100 ppm.

  3. Transverse-longitudinal integrated resonator

    DOEpatents

    Hutchinson, Donald P. (Knoxville, TN); Simpson, Marcus L. (Knoxville, TN); Simpson, John T. (Knoxville, TN)

    2003-03-11

    A transverse-longitudinal integrated optical resonator (TLIR) is disclosed which includes a waveguide, a first and a second subwavelength resonant grating in the waveguide, and at least one photonic band gap resonant structure (PBG) in the waveguide. The PBG is positioned between the first and second subwavelength resonant gratings. An electro-optic waveguide material may be used to permit tuning the TLIR and to permit the TLIR to perform signal modulation and switching. The TLIR may be positioned on a bulk substrate die with one or more electronic and optical devices and may be communicably connected to the same. A method for fabricating a TLIR including fabricating a broadband reflective grating is disclosed. A method for tuning the TLIR's transmission resonance wavelength is also disclosed.

  4. Delta connected resonant snubber circuit

    DOEpatents

    Lai, Jih-Sheng (Knoxville, TN); Peng, Fang Zheng (Oak Ridge, TN); Young, Sr., Robert W. (Oak Ridge, TN); Ott, Jr., George W. (Knoxville, TN)

    1998-01-01

    A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.

  5. Delta connected resonant snubber circuit

    DOEpatents

    Lai, J.S.; Peng, F.Z.; Young, R.W. Sr.; Ott, G.W. Jr.

    1998-01-20

    A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 36 figs.

  6. Crossing of depolarization resonances at saturne (SACLAY)

    NASA Astrophysics Data System (ADS)

    Grorud, E.; Laclare, J.-L.; Leleux, G.; Nakach, A.; Ropert, A.

    1983-03-01

    This paper gives the results of the 1981-1982 campaign of polarization measurements at Saturne. Resonance crossing techniques are given for each type of resonance. The adiabatic crossing of a resonance (spin flip) is proved to be reliable.

  7. Resonant double photoionisation spectroscopy of magnesium

    NASA Astrophysics Data System (ADS)

    Sokell, Emma; Safgren, Stephan; Bolognesi, Paola; Feyer, Vitaliy; Coreno, Marcello; Avaldi, Lorenzo

    2012-11-01

    Resonant triple-differential cross-section (TDCS) measurements on atomic magnesium on the 2p ? 3d resonance are presented. These measurements are similar to recent measurements made in strontium at the 4p ? 4d resonance [1].

  8. Folded dipole plasmonic resonators.

    PubMed

    Choonee, K; Syms, R R A

    2013-11-01

    A class of folded ordered plasmonic dipole nanoresonators based on insulator-metal-insulator (IMI) slab waveguides is proposed and studied. This work is motivated by the development of a novel fabrication process that avoids the need for direct write nanolithography and instead relies on accessible UV lithography and other top-down parallel fabrication techniques that result in metallic dolmen structures with nanometre sized gaps. In this context, the dolmen geometry consists of two vertical segments supporting a flat horizontal slab. It is shown using frequency domain finite element analysis that such structures, which are essentially folded dipole antennas, resonate in a similar manner to their linear unfolded counterparts. The effect of the likely fabrication features is also studied. PMID:24216810

  9. Baryon Spectroscopy and Resonances

    SciTech Connect

    Robert Edwards

    2011-12-01

    A short review of current efforts to determine the highly excited state spectrum of QCD, and in particular baryons, using lattice QCD techniques is presented. The determination of the highly excited spectrum of QCD is a major theoretical and experimental challenge. The experimental investigation of the excited baryon spectrum has been a long-standing element of the hadronic-physics program, an important component of which is the search for so-called 'missing resonances', baryonic states predicted by the quark model based on three constituent quarks but which have not yet been observed experimentally. Should such states not be found, it may indicate that the baryon spectrum can be modeled with fewer effective degrees of freedom, such as in quark-diquark models. In the past decade, there has been an extensive program to collect data on electromagnetic production of one and two mesons at Jefferson Lab, MIT-Bates, LEGS, MAMI, ELSA, and GRAAL. To analyze these data, and thereby refine our knowledge of the baryon spectrum, a variety of physics analysis models have been developed at Bonn, George Washington University, Jefferson Laboratory and Mainz. To provide a theoretical determination and interpretation of the spectrum, ab initio computations within lattice QCD have been used. Historically, the calculation of the masses of the lowest-lying states, for both baryons and mesons, has been a benchmark calculation of this discretized, finite-volume computational approach, where the aim is well-understood control over the various systematic errors that enter into a calculation; for a recent review. However, there is now increasing effort aimed at calculating the excited states of the theory, with several groups presenting investigations of the low-lying excited baryon spectrum, using a variety of discretizations, numbers of quark flavors, interpolating operators, and fitting methodologies. Some aspects of these calculations remain unresolved and are the subject of intense effort, notably the ordering of the Roper resonance in the low-lying Nucleon spectrum.

  10. Cascaded resonant bridge converters

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A. (Inventor)

    1989-01-01

    A converter for converting a low voltage direct current power source to a higher voltage, high frequency alternating current output for use in an electrical system where it is desired to use low weight cables and other circuit elements. The converter has a first stage series resonant (Schwarz) converter which converts the direct current power source to an alternating current by means of switching elements that are operated by a variable frequency voltage regulator, a transformer to step up the voltage of the alternating current, and a rectifier bridge to convert the alternating current to a direct current first stage output. The converter further has a second stage series resonant (Schwarz) converter which is connected in series to the first stage converter to receive its direct current output and convert it to a second stage high frequency alternating current output by means of switching elements that are operated by a fixed frequency oscillator. The voltage of the second stage output is controlled at a relatively constant value by controlling the first stage output voltage, which is accomplished by controlling the frequency of the first stage variable frequency voltage controller in response to second stage voltage. Fault tolerance in the event of a load short circuit is provided by making the operation of the first stage variable frequency voltage controller responsive to first and second stage current limiting devices. The second stage output is connected to a rectifier bridge whose output is connected to the input of the second stage to provide good regulation of output voltage wave form at low system loads.

  11. Auxiliary resonant DC tank converter

    DOEpatents

    Peng, Fang Z. (Knoxville, TN)

    2000-01-01

    An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

  12. Analysis of antioxidants extracted from polypropylene by supercritical fluid extraction.

    PubMed

    Garde, J A; Catalá, R; Gavara, R

    1998-01-01

    Maximal potential migration of six antioxidants (AO) from five polypropylene (PP) formulations was determined by two supercritical fluid extraction (SFE) procedures, both of which contained static and dynamic steps. All analytical conditions affecting the extraction were studied and optimized using Irgafos 168 as standard. SFE was more efficient as temperature and fluid density increased. During the static step in which the samples were exposed to the fluid without flux, the introduction of hexane and methanol as fluid modifiers significantly improved the extraction. Hexane appears to facilitate polymer swelling while methanol solvates the antioxidants. In the dynamic step (in which the extraction actually occurs) time is the key parameter. Extraction for 90 min results in an efficiency of around 75%. The introduction of modifiers during this step (by an HPLC-SFE procedure) did not produce any significant improvement. When SFE was carried out on all samples, extraction efficiency was around 75% except for Irganox 1010 and Hostanox O3. The large molecular volume of these antioxidants may be responsible for the considerable reduction of extraction efficiency. Particle size and shape of polymer sample were also important. The greater the surface to volume ratio the greater the extraction efficiency. PMID:10209581

  13. Statistical Assignment of Neutron Orbital Angular Momentum to a Resonance

    SciTech Connect

    Oh, Soo-Youl [Korea Atomic Energy Research Institute (Korea, Republic of); Chang, Jonghwa [Korea Atomic Energy Research Institute (Korea, Republic of); Leal, Luiz C. [Oak Ridge National Laboratory (United States)

    2004-09-15

    We have derived formulas in a general form for suggesting the neutron orbital angular momentum quantum number l to each neutron resonance if it is not identified experimentally. By assuming the (2J + 1) law of level density, these general formulas are reduced to the formulas found in previous works. The suggestion of l is based on the probability that a resonance having a certain value of g{gamma}{sub n} is an l-wave resonance. The probability is calculated from the Bayes theorem on conditional probability. For each l, the probability density function (pdf) of g{gamma}{sub n} was derived from the {chi}{sup 2} distribution proposed by Porter and Thomas. The pdf takes into account two possible channel spins that result in the same total spin for a given l larger than zero. Meanwhile, regardless of the resolution of measurement, we suggest adopting the level density as the prior probability in the Bayesian approach, as Gyulassy et al. did. As a sample problem, we presented the result of l-assignment for {sup 109}Ag resonances. The SUGGEL code, in which the methodology is incorporated, correctly assigned l's for 67 among 70 resonances for which l's had been determined experimentally. The other test for {sup 27}Al showed the applicability of the code as a preanalysis tool, even though such applicability is limited to a certain extent for light nuclides. The use of the code SUGGEL is expected to reduce the number of repeated runs of a fitting code such as SAMMY, thus reducing time and effort for the extraction of resonance parameters from measurements.

  14. Antioxidative and antiproliferative activities of different horsetail (Equisetum arvense L.) extracts.

    PubMed

    Cetojevi?-Simin, Dragana D; Canadanovi?-Brunet, Jasna M; Bogdanovi?, Gordana M; Djilas, Sonja M; Cetkovi?, Gordana S; Tumbas, Vesna T; Stojiljkovi?, Bratislav T

    2010-04-01

    In this study we investigated antioxidative and antiproliferative activity of different horsetail (Equisetum arvense L.) extracts. The antioxidative activity was measured by the electron spin resonance (ESR) spectroscopy-spin trapping method. The influence of different horsetail extracts during lipid peroxidation of (1) sunflower oil induced by the lipophilic azo-initiator 4,4'-azobis(4-cyanovaleric acid) and (2) soybean phosphatidylcholine liposomes induced by the hydrophilic azo-initiator 2,2'-azobis(2-amidinopropane) dihydrochloride was studied. Antiproliferative activity was measured using the sulforhodamine B colorimetric assay on the human cancer cell lines HeLa, HT-29, and MCF7. The results of ESR analysis confirmed that the extracts investigated suppressed the formation of lipid peroxyl radicals in both systems investigated in a dose-dependent manner. The results indicate that n-butanol, methanol, ethyl acetate, and water extracts had significant peroxyl radical scavenging activity. Extracts inhibited cell growth that was dependent on cell line, type of extract, and extract concentration. Ethyl acetate extract exhibited the most prominent antiproliferative effect, without inducing any cell growth stimulation on human tumor cell lines. The results obtained suggest that the horsetail extracts could be used as an easily accessible source of natural antioxidants and as potential phytochemicals. PMID:20170379

  15. Electron Paramagnetic Resonance -- Nuclear Magnetic Resonance Three Axis Vector Magnetometer

    NASA Astrophysics Data System (ADS)

    Bulatowicz, Michael; Clark, Philip; Griffith, Robert; Larsen, Michael; Mirijanian, James

    2012-06-01

    The Northrop Grumman Corporation is leveraging the technology developed for the Nuclear Magnetic Resonance Gyroscope (NMRG) to build a combined Electron Paramagnetic Resonance -- Nuclear Magnetic Resonance (EPR-NMR) magnetometer. The EPR-NMR approach provides a high bandwidth and high sensitivity simultaneous measurement of all three vector components of the magnetic field averaged over the small volume of the sensor's one vapor cell. This poster will describe the history, operational principles, and design basics of the EPR-NMR magnetometer including an overview of the NSD designs developed and demonstrated to date. General performance results will also be presented.

  16. Evolution of the pygmy dipole resonance in Sn isotopes

    E-print Network

    H. K. Toft; A. C. Larsen; A. Bürger; M. Guttormsen; A. Görgen; H. T. Nyhus; T. Renstrøm; S. Siem; G. M. Tveten; A. Voinov

    2011-05-18

    Nuclear level density and $\\gamma$-ray strength functions of $^{121,122}$Sn below the neutron separation energy are extracted with the Oslo method using the ($^3$He,$^3$He$^\\prime\\gamma$) and ($^3$He,$\\alpha \\gamma$) reactions. The level densities of $^{121,122}$Sn display step-like structures, interpreted as signatures of neutron pair breaking. An enhancement in both strength functions, compared to standard models for radiative strength, is observed in our measurements for $E_\\gamma \\gtrsim 5.2 $ MeV. This enhancement is compatible with pygmy resonances centered at $\\approx 8.4(1)$ and $\\approx 8.6(2)$ MeV, respectively, and with integrated strengths corresponding to $\\approx1.8^{+1}_{-5}%$ of the classical Thomas-Reiche-Kuhn sum rule. Similar resonances were also seen in $^{116-119}$Sn. Experimental neutron-capture cross reactions are well reproduced by our pygmy resonance predictions, while standard strength models are less successful. The evolution as a function of neutron number of the pygmy resonance in $^{116-122}$Sn is described as a clear increase of centroid energy from 8.0(1) to 8.6(2) MeV, but with no observable difference in integrated strengths.

  17. Surface Plasmon Resonance Evaluation of Colloidal Metal Aerogel Filters

    NASA Technical Reports Server (NTRS)

    Smith, David D.; Sibille, Laurent; Cronise, Raymond J.; Noever, David A.

    1997-01-01

    Surface plasmon resonance imaging has in the past been applied to the characterization of thin films. In this study we apply the surface plasmon technique not to determine macroscopic spatial variations but rather to determine average microscopic information. Specifically, we deduce the dielectric properties of the surrounding gel matrix and information concerning the dynamics of the gelation process from the visible absorption characteristics of colloidal metal nanoparticles contained in aerogel pores. We have fabricated aerogels containing gold and silver nanoparticles. Because the dielectric constant of the metal particles is linked to that of the host matrix at the surface plasmon resonance, any change 'in the dielectric constant of the material surrounding the metal nanoparticles results in a shift in the surface plasmon wavelength. During gelation the surface plasmon resonance shifts to the red as the average or effective dielectric constant of the matrix increases. Conversely, formation of an aerogel or xerogel through supercritical extraction or evaporation of the solvent produces a blue shift in the resonance indicating a decrease in the dielectric constant of the matrix. From the magnitude of this shift we deduce the average fraction of air and of silica in contact with the metal particles. The surface area of metal available for catalytic gas reaction may thus be determined.

  18. Evolution of the pygmy dipole resonance in Sn isotopes

    SciTech Connect

    Toft, H. K.; Larsen, A. C.; Buerger, A.; Guttormsen, M.; Goergen, A.; Nyhus, H. T.; Renstroem, T.; Siem, S.; Tveten, G. M. [Department of Physics, University of Oslo, N-0316 Oslo (Norway); Voinov, A. [Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States)

    2011-04-15

    Nuclear level density and {gamma}-ray strength functions of {sup 121,122}Sn below the neutron separation energy are extracted with the Oslo method using the ({sup 3}He,{sup 3}He{sup '{gamma}}) and ({sup 3}He,{alpha}{gamma}) reactions. The level densities of {sup 121,122}Sn display steplike structures, interpreted as signatures of neutron pair breaking. An enhancement in both strength functions, compared to standard models for radiative strength, is observed in our measurements for E{sub {gamma}} > or approx. 5.2 MeV. This enhancement is compatible with pygmy resonances centered at {approx_equal}8.4(1) and {approx_equal}8.6(2) MeV, respectively, and with integrated strengths corresponding to {approx_equal}1.8{sub -5}{sup +1}% of the classical Thomas-Reiche-Kuhn sum rule. Similar resonances were also seen in {sup 116-119}Sn. Experimental neutron-capture cross reactions are well reproduced by our pygmy resonance predictions, while standard strength models are less successful. The evolution as a function of neutron number of the pygmy resonance in {sup 116-122}Sn is described as a clear increase of centroid energy from 8.0(1) to 8.6(2) MeV, but with no observable difference in integrated strengths.

  19. NAMED ENTITY EXTRACTION FROM SPEECH

    Microsoft Academic Search

    Francis Kubala; Richard Schwartz; Ralph Weischedel

    We report results using a hidden Markov model to extract information from broadcast news. IdentiFinder™ was trained on the broadcast news corpus and tested on both the 1996 HUB-4 development test data and the 1997 HUB-4 evaluation test data with respect to the named entity (NE) task: extracting ? names of locations, persons, and organizations;

  20. Extractive reserves in Brazilian Amazonia

    Microsoft Academic Search

    Philip M. Fearnside

    1989-01-01

    In 1985 an opportunity arose for maintaining tracts of Amazonian forest under sustainable use. Brazil's National Council of Rubber Tappers and the Rural Worker's Union proposed the creation of a set of reserves of a new type, called extractive reserves. The first six are being established in one of the Brazilian states most threatened by deforestatation. The creation of extractive

  1. Antifungal activity of juniper extracts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sawdust from three species of Juniperus (i.e., J. virginianna, J. occidentalis, and J. ashei) were extracted with hexane or ethanol and the extracts tested for antifungal activity against four species of wood-rot fungi. These species studied represent the junipers with the greatest potential for co...

  2. PHYSIOLOGICALLY BASED EXTRACTION PROCEDURE (PBEP)

    EPA Science Inventory

    The goal of this project is to develop an extraction procedure which mimics the physiological conditions in the human gastrointestinal track. Using this extraction procedure, the mass of contaminants which desorb from hazardous soil will be estimated. This project has focused ...

  3. Extracting company names from text

    Microsoft Academic Search

    Lisa F. Rau

    1991-01-01

    A detailed description is given of an implemented algorithm that extracts company names automatically from financial news. Extracting company names from text is one problem; recognizing subsequent references to a company is another. The author addresses both problems in an implemented, well-tested module that operates as a detachable process from a set of natural language processing tools. She implements a

  4. Delignification of Miscanthus by Extraction

    Microsoft Academic Search

    Sasisanker Padmanabhan; Edmond Zaia; Katherine Wu; Harvey W. Blanch; Douglas S Clark; Alexis T Bell; John M. Prausnitz

    2011-01-01

    Removal of lignin from miscanthus liberates cellulose and hemicellulose for hydrolysis to obtain sugars that can subsequently be fermented to ethanol or butanol. Extraction of lignin from raw miscanthus at 70°C is feasible when the extracting solvent contains a base (Ethylenediamine, EDA) mixed with an organic solvent or a mildly hydrophobic ionic liquid. A 50–50 (by weight) mixture of EDA

  5. Delignification of Miscanthus by Extraction

    Microsoft Academic Search

    Sasisanker Padmanabhan; Edmond Zaia; Katherine Wu; Harvey W. Blanch; Douglas S. Clark; Alexis T. Bell; John M. Prausnitz

    2012-01-01

    Removal of lignin from miscanthus liberates cellulose and hemicellulose for hydrolysis to obtain sugars that can subsequently be fermented to ethanol or butanol. Extraction of lignin from raw miscanthus at 70°C is feasible when the extracting solvent contains a base (Ethylenediamine, EDA) mixed with an organic solvent or a mildly hydrophobic ionic liquid. A 50–50 (by weight) mixture of EDA

  6. Information Extraction Using Link Grammar

    Microsoft Academic Search

    Norshuhani Zamin; Bandar Seri Iskandar

    2009-01-01

    In the last few years, information extraction (IE) has become a rapidly expanding field as the machine-readable documents keep growing exponentially. IE is the perfect solution to transform factual knowledge from publications into database entries. Many efforts have been made to automatically extract and mine scientific texts ranging from biochemical to terrorism attacks reports. This study is looking into the

  7. Pitch Extraction and Fundamental Frequency

    E-print Network

    Regina, University of

    Pitch Extraction and Fundamental Frequency: History and Current Techniques David Gerhard Technical and Fundamental Frequency: History and Current Techniques David Gerhard Abstract: Pitch extraction (also called fundamental frequency estimation) has been a popular topic in many fields of research since the age

  8. Keyword Extraction Using Language Network

    Microsoft Academic Search

    Jianyi Liu; Jinghua Wang

    2007-01-01

    In this paper, we introduced language network and described three kinds of networks. Keyword extraction is an important technology in many areas of document processing. In particularly, a keyword extraction algorithm based on language network and PageRank is proposed. Firstly a semantic network for a single document is build, then Pagerank is applied in the network to decide on the

  9. Successive solvolytic extraction of petrocrops

    SciTech Connect

    Sharma, D.K.; Pradeep, A.K. [Indian Institute of Technology, Delhi, New Delhi (India); Tiwari, M. [M.D. Univ., Rohtak (India)] [and others

    1996-12-31

    Petrocrops may provide a renewable source of petroleum in the future. The use of low boiling nonpolar (hexane) and polar (methanol) solvents may afford nonpolar and polar biocrudes respectively by successive extractions. However, further successive extraction of spent residue obtained in anthracene oil, quinoline, or liquid paraffin may afford recovery of biopolymer biocrude. These biocrudes may be hydro treated to yield liquid fuels.

  10. Lasing from active optomechanical resonators

    NASA Astrophysics Data System (ADS)

    Czerniuk, T.; Brüggemann, C.; Tepper, J.; Brodbeck, S.; Schneider, C.; Kamp, M.; Höfling, S.; Glavin, B. A.; Yakovlev, D. R.; Akimov, A. V.; Bayer, M.

    2014-07-01

    Planar microcavities with distributed Bragg reflectors (DBRs) host, besides confined optical modes, also mechanical resonances due to stop bands in the phonon dispersion relation of the DBRs. These resonances have frequencies in the 10- to 100-GHz range, depending on the resonator’s optical wavelength, with quality factors exceeding 1,000. The interaction of photons and phonons in such optomechanical systems can be drastically enhanced, opening a new route towards the manipulation of light. Here we implemented active semiconducting layers into the microcavity to obtain a vertical-cavity surface-emitting laser (VCSEL). Thereby, three resonant excitations—photons, phonons and electrons—can interact strongly with each other providing modulation of the VCSEL laser emission: a picosecond strain pulse injected into the VCSEL excites long-living mechanical resonances therein. As a result, modulation of the lasing intensity at frequencies up to 40?GHz is observed. From these findings, prospective applications of active optomechanical resonators integrated into nanophotonic circuits may emerge.

  11. Annular Bragg defect mode resonators

    NASA Astrophysics Data System (ADS)

    Scheuer, Jacob; Green, William M. J.; DeRose, Guy; Yariv, Amnon

    2004-06-01

    We propose and analyze a new type of resonator in an annular geometry which is based on a single defect surrounded by radial Bragg reflectors on both sides. Unlike conventional, total internal reflection based ring resonators, this structure supports modal fields with very low azimuthal number (large radial k-vector component). We show that the conditions for efficient mode confinement are different from those of conventional Bragg waveguiding in a rectangular geometry. To realize tight confinement of the light in the defect, chirped gratings are required. Compared to a conventional resonator, the new resonator exhibits larger FSR and lower losses making it suitable for both telecom and sensing applications. In addition, the resonance wavelength and Q factor of the device are very sensitive to environmental changes, and thus provide ideal observables for sensing applications. Annular Bragg resonators with several unique geometries have been fabricated in an InGaAsP multi-quantum-well membrane. The spectral properties of the resonators have been investigated through analysis of photoluminescence induced by pulsed optical excitation.

  12. Conserved number fluctuations in a hadron resonance gas model

    NASA Astrophysics Data System (ADS)

    Garg, P.; Mishra, D. K.; Netrakanti, P. K.; Mohanty, B.; Mohanty, A. K.; Singh, B. K.; Xu, N.

    2013-11-01

    Net-baryon, net-charge and net-strangeness number fluctuations in high energy heavy-ion collisions are discussed within the framework of a hadron resonance gas (HRG) model. Ratios of the conserved number susceptibilities calculated in HRG are being compared to the corresponding experimental measurements to extract information about the freeze-out condition and the phase structure of systems with strong interactions. We emphasize the importance of considering the actual experimental acceptances in terms of kinematics (pseudorapidity (?) and transverse momentum (pT)), the detected charge state, effect of collective motion of particles in the system and the resonance decay contributions before comparisons are made to the theoretical calculations. In this work, based on HRG model, we report that the net-baryon number fluctuations are least affected by experimental acceptances compared to the net-charge and net-strangeness number fluctuations.

  13. Optofluidic ring resonator dye lasers

    NASA Astrophysics Data System (ADS)

    Sun, Yuze; Suter, Jonathan D.; Fan, Xudong

    2010-02-01

    We overview the recent progress on optofluidic ring resonator (OFRR) dye lasers developed in our research group. The fluidics and laser cavity design can be divided into three categories: capillary optofluidic ring resonator (COFRR), integrated cylindrical optofluidic ring resonator (ICOFRR), and coupled optofluidic ring resonator (CpOFRR). The COFRR dye laser is based on a micro-sized glass capillary with a wall thickness of a few micrometers. The capillary circular cross-section forms the ring resonator and supports the whispering gallery modes (WGMs) that interact evanescently with the gain medium in the core. The laser cavity structure is versatile to adapt to the gain medium of any refractive index. Owing to the high Q-factor (>109), the lasing threshold of 25 nJ/mm2 is achieved. Besides directly pump the dye molecules, lasing through fluorescence resonance energy transfer (FRET) between the donor and acceptor dye molecules is also studied in COFRR laser. The energy transfer process can be further controlled by designed DNA scaffold labeled with donor/acceptor molecules. The ICOFRR dye laser is based on a cylindrical ring resonator fused onto the inner surface of a thick walled glass capillary. The structure has robust mechanical strength to sustain rapid gain medium circulation. The CpOFRR utilizes a cylindrical ring resonator fused on the inner surface of the COFRR capillary. Since the capillary wall is thin, the individual WGMs of the cylindrical ring resonator and the COFRR couples strongly and forms Vernier effect, which provides a way to generate a single mode dye laser.

  14. Nonlocal Intracranial Cavity Extraction

    PubMed Central

    Manjón, José V.; Eskildsen, Simon F.; Coupé, Pierrick; Romero, José E.; Collins, D. Louis; Robles, Montserrat

    2014-01-01

    Automatic and accurate methods to estimate normalized regional brain volumes from MRI data are valuable tools which may help to obtain an objective diagnosis and followup of many neurological diseases. To estimate such regional brain volumes, the intracranial cavity volume (ICV) is often used for normalization. However, the high variability of brain shape and size due to normal intersubject variability, normal changes occurring over the lifespan, and abnormal changes due to disease makes the ICV estimation problem challenging. In this paper, we present a new approach to perform ICV extraction based on the use of a library of prelabeled brain images to capture the large variability of brain shapes. To this end, an improved nonlocal label fusion scheme based on BEaST technique is proposed to increase the accuracy of the ICV estimation. The proposed method is compared with recent state-of-the-art methods and the results demonstrate an improved performance both in terms of accuracy and reproducibility while maintaining a reduced computational burden. PMID:25328511

  15. Evaluation of the Chromium Resonance Parameters Including Resonance Parameter Covariance

    SciTech Connect

    Leal, Luiz C [ORNL; Derrien, Herve [ORNL; Guber, Klaus H [ORNL; Arbanas, Goran [ORNL; Wiarda, Dorothea [ORNL

    2011-01-01

    The intent of this work is to report the results and describe the procedures utilized to evaluate the chromium isotopes' cross sections, i.e., (50)Cr, (52)Cr, (53)Cr, and (54)Cr, for criticality safety applications. The evaluations were done in the resolved resonance region using the reduced Reich-Moore R-matrix formalism. The novel aspect of this evaluation is the inclusion of new transmission and capture cross-section measurements performed at the Oak Ridge Electron Linear Accelerator (ORELA) for energies below 100 keV and the extension of the (53)Cr energy region. The resonance analysis was performed with the multilevel R-matrix code, SAMMY, which utilizes the generalized least-squares technique based on the Bayes' theory. Complete sets of resonance parameters and resonance parameter covariance matrices (RPCMs) were obtained for each of the chromium isotopes from the SAMMY analysis of the experimental database.

  16. Stepped Impedance Resonators for High Field Magnetic Resonance Imaging

    PubMed Central

    Akgun, Can E.; DelaBarre, Lance; Yoo, Hyoungsuk; Sohn, Sung-Min; Snyder, Carl J.; Adriany, Gregor; Ugurbil, Kamil; Gopinath, Anand; Vaughan, J. Thomas

    2014-01-01

    Multi-element volume radio-frequency (RF) coils are an integral aspect of the growing field of high field magnetic resonance imaging (MRI). In these systems, a popular volume coil of choice has become the transverse electromagnetic (TEM) multi-element transceiver coil consisting of microstrip resonators. In this paper, to further advance this design approach, a new microstrip resonator strategy in which the transmission line is segmented into alternating impedance sections referred to as stepped impedance resonators (SIRs) is investigated. Single element simulation results in free space and in a phantom at 7 tesla (298 MHz) demonstrate the rationale and feasibility of the SIR design strategy. Simulation and image results at 7 tesla in a phantom and human head illustrate the improvements in transmit magnetic field, as well as, RF efficiency (transmit magnetic field versus SAR) when two different SIR designs are incorporated in 8-element volume coil configurations and compared to a volume coil consisting of microstrip elements. PMID:23508243

  17. Magnetic resonance in solids

    SciTech Connect

    O'Connell, A.J.

    1992-01-01

    In this thesis electron paramagnetic resonance (EPR) and electro-nuclear double resonance (ENDOR) experiments are reported on paramagnetic defects in two host materials: (a) Cr[sup 3+] in the ferroelectric lecontite and (b) color centres and the Fe[sup 3+] centre in lithium oxide. A. Lecontite. Lecontite, NaNH[sub 4]SO[sub 4][center dot]2H[sub 2]O, undergoes a phase transition to a ferroelectric phase below [Tc] = 101 K. Reported here are EPR measurements on doped Cr[sup 3+] ions at two distinct sites, made at a variety of temperatures in an attempt to ascertain the details of the structural changes occurring at [Tc]. The room temperature data are compared to various models for the two defects using the Newman superposition model. The results show that the Cr[sup 3+] ions are at Na[sup +] sites, highly distorted due to charge compensation of the trivalent dopant and therefore that the EPR of these defects is not representative of the bulk material. B. Lithium oxide. Investigations of three defect in lithium oxide, Li[sub 2]O are reported here. (i) The electronic F[sup +] -centre has been investigated using EPR and [sup 7]Li ENDOR to determine the transferred hyperfine structure (THFS) due to hyperfine interactions of the defect wavefunction with the ligand nuclei. Comparison with F-centres in other simple ionic hosts shows that the centre is highly localized and this observation is explained by the charge states of the ligands and the defect site. (ii) EPR and [sup 7]Li ENDOR of the interstitial neutral hydrogen centre H[sup 0] show a novel tunnelling effect. At low temperatures the defect has tetragonal symmetry but at higher temperatures there is evidence of tunnelling between six equivalent sites, leading to effective cubic symmetry. (iii) THFS of Fe[sup 3+] centres, measured using [sup 7]Li ENDOR, interpreted using the Newman superposition model, are used to determine the distortions of the neighboring ligands.

  18. Guided resonance reflective phase shifters

    NASA Astrophysics Data System (ADS)

    Horie, Yu; Arbabi, Amir; Faraon, Andrei

    2015-02-01

    We present reflective phase shifters based on high contrast gratings resting on a low-index spacer backed by a metallic mirror. The guided resonance of the grating combined with the reflection from the metallic mirror leads to an all-pass filter with 2? phase shift variation and unity reflectivity across the resonance. We present simulations, fabrication and measurement of passive devices fabricated in silicon over gold using a polymer as the spacer layer. Active control at high modulation speeds can be achieved by shifting the guided resonance wavelength using carrier injection or thermo-optic effect in silicon.

  19. Multiple resonant railgun power supply

    DOEpatents

    Honig, E.M.; Nunnally, W.C.

    1985-06-19

    A multiple repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. A plurality of serially connected paired parallel rails are powered by similar power supplies. Each supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles. The multiple serial operation permits relatively small energy components to deliver overall relatively large amounts of energy to the projectiles being propelled.

  20. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

    1997-12-30

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.

  1. Resonant and non-resonant microwave absorption as a probe of the magnetic dynamics and switching in spin valves

    NASA Astrophysics Data System (ADS)

    Timopheev, A. A.; Sobolev, N. A.; Pogorelov, Y. G.; Talalaevskij, A. V.; Teixeira, J. M.; Cardoso, S.; Freitas, P. P.; Kakazei, G. N.

    2013-07-01

    We use the resonant and non-resonant microwave absorption to probe the dynamic and static magnetic parameters of weakly coupled spin valves. The sample series include spin valve structures with varying thickness of the non-magnetic metallic spacer and reference samples comprised only a free or fixed magnetic layer. Beside the common resonance absorption peaks, the observed microwave spectra present step-like features with hysteretic behavior. The latter effect is a direct manifestation of the interlayer coupling between the ferromagnetic layers and provides two static magnetic parameters, the switching field and coercivity of the fixed layer. The analysis of the microwave absorption spectra under in-plane rotation of the applied magnetic field at different spacer thicknesses permits a deeper insight in the magnetic interactions in this system as compared to the conventional magnetometry. We combine the standard Smit-Beljers formalism for the angular dependence of the resonance fields with a Landau-Lifshitz-Gilbert dynamics extended to describe in detail the intensity of microwave absorption in the spin valves. In this way, we extract a set of parameters for each layer including the effective magnetization and anisotropy, exchange bias and interlayer coupling, as well as Gilbert damping. The model reproduces well the experimental findings, both qualitatively and quantitatively, and the estimated parameters are in a reasonable agreement with the values known from the literature. The proposed theoretical treatment can be adopted for other multilayered dynamic systems as, e.g., spin-torque oscillators.

  2. High quality factor nanocrystalline diamond micromechanical resonators limited by thermoelastic damping

    NASA Astrophysics Data System (ADS)

    Najar, Hadi; Chan, Mei-Lin; Yang, Hsueh-An; Lin, Liwei; Cahill, David G.; Horsley, David A.

    2014-04-01

    We demonstrate high quality factor thin-film nanocrystalline diamond micromechanical resonators with quality factors limited by thermoelastic damping. Cantilevers, single-anchored and double-anchored double-ended tuning forks, were fabricated from 2.5 ?m thick in-situ boron doped nanocrystalline diamond films deposited using hot filament chemical vapor deposition. Thermal conductivity measured by time-domain thermoreflectance resulted in 24 ± 3 W m-1 K-1 for heat transport through the thickness of the diamond film. The resonant frequencies of the fabricated resonators were 46 kHz-8 MHz and showed a maximum measured Q ? 86 000 at fn = 46.849 kHz. The measured Q-factors are shown to be in good agreement with the limit imposed by thermoelastic dissipation calculated using the measured thermal conductivity. The mechanical properties extracted from resonant frequency measurements indicate a Young's elastic modulus of ?788 GPa, close to that of microcrystalline diamond.

  3. Green's function method for single-particle resonant states in relativistic mean field theory

    E-print Network

    T. T. Sun; S. Q. Zhang; Y. Zhang; J. N. Hu; J. Meng

    2014-09-30

    Relativistic mean field theory is formulated with the Green's function method in coordinate space to investigate the single-particle bound states and resonant states on the same footing. Taking the density of states for free particle as a reference, the energies and widths of single-particle resonant states are extracted from the density of states without any ambiguity. As an example, the energies and widths for single-neutron resonant states in $^{120}$Sn are compared with those obtained by the scattering phase-shift method, the analytic continuation in the coupling constant approach, the real stabilization method and the complex scaling method. Excellent agreements are found for the energies and widths of single-neutron resonant states.

  4. Coupling of a locally implanted rare-earth ion ensemble to a superconducting micro-resonator

    NASA Astrophysics Data System (ADS)

    Wisby, I.; de Graaf, S. E.; Gwilliam, R.; Adamyan, A.; Kubatkin, S. E.; Meeson, P. J.; Tzalenchuk, A. Ya.; Lindström, T.

    2014-09-01

    We demonstrate the coupling of rare-earth ions locally implanted in a substrate (Gd3+ in Al2O3) to a superconducting NbN lumped-element micro-resonator. The hybrid device is fabricated by a controlled ion implantation of rare-earth ions in well-defined micron-sized areas, aligned to lithographically defined micro-resonators. The technique does not degrade the internal quality factor of the resonators which remain above 105. Using microwave absorption spectroscopy, we observe electron-spin resonances in good agreement with numerical modelling and extract corresponding coupling rates of the order of 1 MHz and spin linewidths of 50-65 MHz.

  5. Coupling of a locally implanted rare-earth ion ensemble to a superconducting micro-resonator

    E-print Network

    I. Wisby; S. E. de Graaf; R. Gwilliam; A. Adamyan; S. Kubatkin; P. J. Meeson; A. Ya. Tzalenchuk; T. Lindström

    2014-09-10

    We demonstrate the coupling of rare-earth ions locally implanted in a substrate (Gd$^{3+}$ in Al$_{2}$O$_{3}$) to a superconducting NbN lumped-element micro-resonator. The hybrid device is fabricated by a controlled ion implantation of rare-earth ions in well-defined micron-sized areas, aligned to lithographically defined micro-resonators. The technique does not degrade the internal quality factor of the resonators which remain above $10^{5}$. Using microwave absorption spectroscopy we observe electron-spin resonances in good agreement with numerical modelling and extract corresponding coupling rates of the order of $1$ MHz and spin linewidths of $50 - 65$ MHz.

  6. Integrated modeling of electron cyclotron resonance ion sources and charge breeders with GEM, MCBC, and IonEx

    SciTech Connect

    Kim, J. S.; Zhao, L.; Cluggish, B. P.; Galkin, S. A.; Grubert, J. E. [FAR-TECH, Inc., 3550 General Atomics Court, MS 15-155, San Diego, California 92121 (United States); Pardo, R. C.; Vondrasek, R. C. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2010-02-15

    A numerical toolset to help in understanding physical processes in the electron cyclotron resonance charge breeder (ECRCB) and further to help optimization and design of current and future machines is presented. The toolset consists of three modules (Monte Carlo charge breeding code, generalized electron cyclotron resonance ion source modeling, and ion extraction), each modeling different processes occurring in the ECRCB from beam injection to extraction. The toolset provides qualitative study, such as parameter studies, and scaling of the operation, and physical understanding in the ECRCB. The methodology and a sample integrated modeling are presented.

  7. Ferromagnetic Resonance Imaging with Magnetic Resonance Force Microscopy

    NASA Astrophysics Data System (ADS)

    Pelekhov, Denis

    2009-03-01

    Magnetic resonance force microscopy achieves very high resolution three-dimensional imaging capabilities of magnetic resonance imaging by taking advantage of very high sensitivity mechanical force detection. This enables non-contacting, microscopic studies and imaging of a broad range of materials. As a consequence of the strong interactions between spins, the assumptions underlying conventional MRI are not applicable to FMR imaging. However, using a new approach to localizing the resonant volume in an FMR measurement founded on the strong, nonuniform magnetic field of the micromagnetic probe tip, we have demonstrated scanned probe Ferromagnetic Resonance (FMR) imaging [1]. The scanned probe FMR images obtained in patterned ferromagnetic films are well explained by detailed numerical modeling. In addition to illuminating the mechanisms underlying localized FMR, the model provides the basis for submicron scanned probe FMR imaging of films and buried ferromagnetic elements. This work was supported by the U.S. Department of Energy through Grant No. DE-FG02-03ER46054. [1] ``Local Ferromagnetic Resonance Imaging with Magnetic Resonance Force Microscopy,'' Yu. Obukhov, D.V. Pelekhov, J. Kim, P. Banerjee, I. Martin, E. Nazaretski, R. Movshovich, S. An, T.J. Gramila, S. Batra, and P. C. Hammel, Phys. Rev. Lett. 100(19), 197601 (2008).

  8. Barium Tagging from nEXO Using Resonance Ionization Spectroscopy

    NASA Astrophysics Data System (ADS)

    Twelker, K.; Kravitz, S.

    nEXO is a 5-ton liquid enriched-xenon time projection chamber (TPC) to search for neutrinoless double-beta decay, designed to have the sensitivity to completely probe the inverted mass hierarchy of Majorana neutrinos. The detector will accommodate-as a background reduction technique-a system to recover and identify the barium decay product. This upgrade will allow a background-free measurement of neutrinoless double-beta decay and increase the half-life sensitivity of the experiment by at least one order of magnitude. Ongoing research and development includes a system to test barium extraction from liquid xenon using surface adsorption and Resonance Ionization Spectroscopy (RIS).

  9. Near-field microwave probe for local ferromagnetic resonance characterization

    NASA Astrophysics Data System (ADS)

    Mircea, Dragos I.; Clinton, T. W.

    2007-04-01

    A local ferromagnetic resonance (FMR) technique using a thin-film microwave probe fabricated on coaxial transmission line is presented. Some key features of this probe are its micron-scale size coupled with broadband FMR characterization and mobility: a small area of any location on a magnetic medium can be probed. Permeability of Permalloy (Py) films has been measured, where the authors extract physical parameters, such as FMR frequency, anisotropy field, damping, and spin wave exchange constant, in excellent agreement with independent measurements. Samples of arbitrary shape and size can be measured with a spatial resolution that scales with the size of the probe "tip."

  10. Deposition of diamondlike films by electron cyclotron resonance microwave plasmas

    NASA Technical Reports Server (NTRS)

    Pool, F. S.; Shing, Y. H.

    1990-01-01

    Hard a-C:H films have been deposited through electron cyclotron resonance (ECR) microwave plasma decomposition of CH4 diluted with H2 gas. It has been found that hard diamondlike films could only be produced under a RF-induced negative self-bias of the substrate stage. Raman spectra indicate the deposition of two distinct film types: one film type exhibiting well-defined bands at 1360 and 1580/cm and another displaying a broad Raman peak centered at approximately 1500/cm. Variation of the mirror magnetic-field profile of the ECR system was examined, demonstrating the manipulation of film morphology through the extraction of different ion energies.

  11. Surface plasmon resonance arrays

    NASA Astrophysics Data System (ADS)

    Suriono, Usman

    This thesis work describes the development of a prototype of multiple channel biosensor based on the principle of Surface Plasmon Resonance. Particularly, a device consists of an array of 864 channels sensor has been designed and fabricated, providing an efficient, high throughput and cost-effective method to analyze multiple DNA samples simultaneously. The sensor device design is derived from the Kretschmann geometry. The glass prism is integrated with the sensor chip by having an opto-interface sheet sandwich between them. The sensor chip is fabricated by utilizing microelectronics process such as photolithography, plasma etching, E-beam, and anodic bonding. Each sensor channel has a dimension of 500 microns width, 1200 microns height, and 500 microns depth which can hold liquid with volume up to 0.3 mm 3. However, the sensor actuation, to advance from one channel to another, is accomplished by rotating the sensor chip, like a CDROM player. The device is characterized for the optimum performance, modeling, and calibration purpose. Metal layer properties are used as the parameters for performance optimization. For the device modeling and calibration, thin film PECVD silicon oxide is deposited on gold surface at different thickness. Biomolecular binding between Avidin and Biotin is used as a demonstration of SPR arrays application. The device is capable of detecting the binding, including binding at different concentrations of Avidin. Finally, several other potential applications of SPR sensor are also proposed.

  12. Nuclear Magnetic Resonance

    NASA Astrophysics Data System (ADS)

    Reuhs, Bradley L.; Simsek, Senay

    Nuclear magnetic resonance (NMR) spectroscopy is a powerful analytical technique with a wide variety of applications. It may be used for complex structural studies, for protocol or process development, or as a simple quality assay for which structural information is important. It is nondestructive, and high-quality data may be obtained from milligram, even microgram, quantities of sample. Whereas other spectroscopy techniques may be used to determine the nature of the functional groups present in a sample, only NMR spectroscopy can provide the data necessary to determine the complete structure of a molecule. The applicability of NMR to food analysis has increased over the last three decades. In addition to improved instrumentation and much lower costs, very complex and specialized NMR techniques can now be routinely performed by a student or technician. These experiments can be set up with the click of a button/icon, as all the basic parameters are embedded into default experiment files listed in the data/work station software, and the results are obtained in a short time.

  13. Magnetic resonance cell

    SciTech Connect

    Kwon, T.M.; Volk, C.H.

    1984-05-01

    There is disclosed a nuclear magnetic alignment device for use in a nuclear magnetic resonance gyroscope and the like. One embodiment includes a container for gas having a layer of rubidium hydride on its inner surface. The container comprising a spherical portion and a tip portion, is rotationally symmetric about an axis of symmetry. Enclosed within the container is a nuclear moment gas having a nuclear electric quadrupole moment, such as xenon-131, and an optically pumpable substance, such as rubidium. A portion of the rubidium is a vapor. The remainder is a condensed pellet which is deposited in the tip of the container such that the pellet is also rotationally symmetric about the axis of symmetry of the container. A layer of rubidium hydride is deposited on the inner surface of the container. The device further includes means for orienting the symmetry axis of the container at an angle to an applied magnetic field such that the relaxation time constant of the aligned nuclear moment gas is substantially at a maximum.

  14. Pressurized liquid extraction of medicinal plants

    Microsoft Academic Search

    Björn Benthin; Henning Danz; Matthias Hamburger

    1999-01-01

    The suitability of pressurized liquid extraction (PLE) in medicinal plant analysis was investigated. PLE extracts from a selection of representative herbs were compared with extracts obtained according to Pharmacopoeia monographs with respect to yield of relevant plant constituents, extraction time and solvent consumption. In all cases a significant economy in time and solvents was realized, while extraction yields of the

  15. A micro-machined resonator

    SciTech Connect

    Godshall, N.A.; Koehler, D.R.; Liang, A.Y.; Smith, B.K.

    1991-12-31

    This invention is comprised of a micro-machined resonator, typically quartz, with upper and lower micromachinable support members, or covers, having etched wells which may be lined with conductive electrode material, between the support members is a quartz resonator having an energy trapping quartz mesa capacitively coupled to the electrodes through a diaphragm; the quartz resonator is supported by either micro-machined cantilever springs or by thin layers extending over the surfaces of the support. If the diaphragm is rigid, clock applications are available, and if the diaphragm is resilient, then transducer applications can be achieved. Either the thin support layers or the conductive electrode material can be integral with the diaphragm. In any event, the covers are bonded to form a hermetic seal and the interior volume may be filled with a gas or may be evacuated. In addition, one or both of the covers may include oscillator and interface circuitry for the resonator.

  16. Morphological resonances for multicomponent immunoassays

    NASA Astrophysics Data System (ADS)

    Whitten, W. B.; Shapiro, M. J.; Ramsey, J. M.; Bronk, B. V.

    1995-06-01

    An immunoassay technique capable of detecting and identifying a number of species of microorganisms in a single analysis is described. The method uses optical-resonance size discrimination of microspheres to identify antibodies to which stained microorganisms are bound.

  17. Orbital resonances in exoplanetary systems

    NASA Astrophysics Data System (ADS)

    Popova, E. A.; Shevchenko, I. I.

    2014-12-01

    At present, more than 700 exoplanetary systems are known to have been discovered. They incorporate more than 130 multiplanet systems, i.e. those hosting two or more planets. The orbital resonance and near-resonance phenomena are ubiquitous in them. We present a statistical and dynamical analysis of the resonance structure of the multiplanet systems and planetary systems of binary stars. We have built distributions of the orbital period ratios, separately considering the cases of inner and outer location of the massive perturber. The histograms reveal apparent peaks close to the first order orbital resonances 2/1 and 3/2 in both cases; this confirms previous findings. We have performed analytical modelling of the histograms, and obtained exact positions of the peaks. Moreover, we have built the "period ratio – eccentricity" diagrams, with collision curves superimposed, so that to find anomalous systems.

  18. Frequency response of resonant converters

    Microsoft Academic Search

    K. Siri; C. Q. Lee; S. J. Fang

    1990-01-01

    The general theory of the discrete small-signal analyses of resonant converters has been formulated in a closed form. For simplicity and verification, the state-plane diagram technique is used for the analysis. This theory is applicable to converters in half-bridge or full-bridge configurations when operated in the continuous conduction mode. Using a series resonant converter (SRC) as an example, the analytic

  19. Empathy in schizophrenia: impaired resonance

    Microsoft Academic Search

    Helene Haker; Wulf Rössler

    2009-01-01

    Resonance is the phenomenon of one person unconsciously mirroring the motor actions as basis of emotional expressions of another\\u000a person. This shared representation serves as a basis for sharing physiological and emotional states of others and is an important\\u000a component of empathy. Contagious laughing and contagious yawning are examples of resonance. In the interpersonal contact with\\u000a individuals with schizophrenia we

  20. Resonance Constraints on Rhythmic Movement

    Microsoft Academic Search

    Paul J. Treffner; M. T. Turvey

    1993-01-01

    The component frequencies of rhythmic patterns forming rational ratios, either simple (e.g., 1:2, 1:3) or complex (e.g., 2:3, 2:5), are known as mode locks or resonances. A general theory of resonances is provided by the circle map, the Farey series, and continued fractions. Predictions were evaluated in which rhythms (simple and poly) were established implicitly—the subject neither intended them nor

  1. Resonant snubbers with auxiliary switches

    Microsoft Academic Search

    W. McMurray

    1989-01-01

    A resonant snubber is described for voltage-source inverters, current-source inverters, and self-commutated frequency changers. The main self-turn-off devices have shunt capacitors directly across them. The lossless resonant snubber described avoids trapping energy in a converter circuit where high dynamic stresses at both turn-on and turn-off are normally encountered. This is achieved by providing a temporary parallel path through a small

  2. Injecting asteroid fragments into resonances

    NASA Technical Reports Server (NTRS)

    Farinella, Paolo; Gonczi, R.; Froeschle, Christiane; Froeschle, Claude

    1992-01-01

    We have quantitatively modeled the chance insertion of asteroid collisional fragments into the 3:1 and g = g(sub 6) resonances, through which they can achieve Earth-approaching orbits. Although the results depend on some poorly known parameters, they indicate that most meteorites and near-earth asteroids probably come from a small and non-representative sample of asteroids, located in the neighborhood of the two resonances.

  3. Wavelength tracking with thermally controlled silicon resonators

    E-print Network

    Mellor-Crummey, John

    of the resonant wavelength of a silicon dual-ring resonator. The feedback signal is the difference in optical-optic tuning with micro-heaters. This control scheme keeps the central wavelength of the resonator aligning, and R. Baets, "Athermal Silicon-on-insulator ring resonators by overlaying a polymer cladding

  4. Endovascular extraction techniques for pacemaker and ICD lead extraction

    PubMed Central

    Bracke, F.A.; Meijer, A.; van Gelder, B.

    2001-01-01

    In the last few years, comprehensive endovascular techniques have been developed to extract chronically implanted pacemaker and defibrillator leads. It is important that referring physician have knowledge of the advantages and limitations of the different techniques. In this paper we discuss the techniques and results of the currently used endovascular extraction techniques. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:25696690

  5. Tactile resonance sensors in medicine.

    PubMed

    Lindahl, O A; Constantinou, C E; Eklund, A; Murayama, Y; Hallberg, P; Omata, S

    2009-01-01

    Tactile sensors in general are used for measuring the physical parameters associated with contact between sensor and object. Tactile resonance sensors in particular are based on the principle of measuring the frequency shift, Deltaf, defined as the difference between a freely vibrating sensor resonance frequency and the resonance frequency measured when the sensor makes contact to an object. Deltaf is therefore related to the acoustic impedance of the object and can be used to characterize its material properties. In medicine, tactile resonance sensor systems have been developed for the detection of cancer, human ovum fertility, eye pressure and oedema. In 1992 a Japanese research group published a paper presenting a unique phase shift circuit to facilitate resonance measurements. In this review we summarize the current state-of-the-art of tactile resonance sensors in medicine based on the phase shift circuit and discuss the relevance of the measured parameters for clinical diagnosis. Future trends and applications enabled by this technology are also predicted. PMID:19384701

  6. Spin resonance without spin splitting

    NASA Astrophysics Data System (ADS)

    Hell, M.; Sothmann, B.; Leijnse, M.; Wegewijs, M. R.; König, J.

    2015-05-01

    We predict that a single-level quantum dot without discernible splitting of its spin states develops a spin-precession resonance in charge transport when embedded into a spin valve. The resonance occurs in the generic situation of Coulomb blockaded transport with ferromagnetic leads whose polarizations deviate from perfect antiparallel alignment. The resonance appears when electrically tuning the interaction-induced exchange field perpendicular to one of the polarizations—a simple condition relying on vectors in contrast to usual resonance conditions associated with energy splittings. The spin resonance can be detected by stationary d I /d V spectroscopy and by oscillations in the time-averaged current using a gate-pulsing scheme. The generic noncollinearity of the ferromagnets and junction asymmetry allow for an all-electric determination of the spin-injection asymmetry, the anisotropy of spin relaxation, and the magnitude of the exchange field. We also investigate the impact of a nearby superconductor on the resonance position. Our simplistic model turns out to be generic for a broad class of coherent few-level quantum systems.

  7. Extraction and elemental analysis of Coleus forskohlii extract

    PubMed Central

    Kanne, Haritha; Burte, Narayan Pandurang; Prasanna, V.; Gujjula, Ravi

    2015-01-01

    Background: Coleus forskohlii Willd. is a popular traditional medicine used since ancient times for treatment of heart diseases, abdominal colic and respiratory disorders. Objective: The aim of this study was to characterize the root extract of the medicinal plant Coleus forskohlii. Materials and Methods: Dry roots of C. forskohlii were used to extract Forskolin using toluene as a solvent. Thus, obtained extract of C. forskohlii was standardized to 30% and used for further studies. Results: The physical properties of the extract were analyzed through scanning electron microscopy analysis, while the characterization of root extract through X-ray diffraction (XRD) and element analysis. The morphological feature of the C. forskohlii extract showed a flake like structure and the XRD showed sulfur trioxide (SO3) and trimer of sulfur trioxide (S3 O9). Through element analysis, elements such as carbon, oxygen, magnesium, aluminum, silicon, phosphorous, and sulfur were identified. Carbon showed the highest weight of 75.49% in comparison to all other elements.

  8. Extraction, isolation and characterization of bioactive compounds from plants' extracts.

    PubMed

    Sasidharan, S; Chen, Y; Saravanan, D; Sundram, K M; Yoga Latha, L

    2011-01-01

    Natural products from medicinal plants, either as pure compounds or as standardized extracts, provide unlimited opportunities for new drug leads because of the unmatched availability of chemical diversity. Due to an increasing demand for chemical diversity in screening programs, seeking therapeutic drugs from natural products, interest particularly in edible plants has grown throughout the world. Botanicals and herbal preparations for medicinal usage contain various types of bioactive compounds. The focus of this paper is on the analytical methodologies, which include the extraction, isolation and characterization of active ingredients in botanicals and herbal preparations. The common problems and key challenges in the extraction, isolation and characterization of active ingredients in botanicals and herbal preparations are discussed. As extraction is the most important step in the analysis of constituents present in botanicals and herbal preparations, the strengths and weaknesses of different extraction techniques are discussed. The analysis of bioactive compounds present in the plant extracts involving the applications of common phytochemical screening assays, chromatographic techniques such as HPLC and, TLC as well as non-chromatographic techniques such as immunoassay and Fourier Transform Infra Red (FTIR) are discussed. PMID:22238476

  9. Atomic resonance spectrometers and filters (review)

    SciTech Connect

    Matveev, O.I.

    1987-09-01

    The authors review the physical principles of recording and filtering light quanta with the aid of atomic resonance media and assess the latest accomplishments and future applications of atomic resonance spectrometers and filters in various fields. Specific topics include fluorescence resonance spectrometers and their performance in absorption and emission spectroscopy;fluorescence resonance spectrometers working with excited atoms; resonance absorption filters; optoacoustic resonance spectrometers; magneto-optical filters; ionization resonance spectrometers using lasers; frequency standards for laser radiation and the detection of infrared and ultrahigh-frequency radiation.

  10. Microelectromechanical resonator and method for fabrication

    DOEpatents

    Wittwer, Jonathan W. (Albuquerque, NM); Olsson, Roy H. (Albuquerque, NM)

    2009-11-10

    A method is disclosed for the robust fabrication of a microelectromechanical (MEM) resonator. In this method, a pattern of holes is formed in the resonator mass with the position, size and number of holes in the pattern being optimized to minimize an uncertainty .DELTA.f in the resonant frequency f.sub.0 of the MEM resonator due to manufacturing process variations (e.g. edge bias). A number of different types of MEM resonators are disclosed which can be formed using this method, including capacitively transduced Lame, wineglass and extensional resonators, and piezoelectric length-extensional resonators.

  11. Microelectromechanical resonator and method for fabrication

    DOEpatents

    Wittwer, Jonathan W. (Albuquerque, NM); Olsson, Roy H. (Albuquerque, NM)

    2010-01-26

    A method is disclosed for the robust fabrication of a microelectromechanical (MEM) resonator. In this method, a pattern of holes is formed in the resonator mass with the position, size and number of holes in the pattern being optimized to minimize an uncertainty .DELTA.f in the resonant frequency f.sub.0 of the MEM resonator due to manufacturing process variations (e.g. edge bias). A number of different types of MEM resonators are disclosed which can be formed using this method, including capacitively transduced Lame, wineglass and extensional resonators, and piezoelectric length-extensional resonators.

  12. Evaluation of the antioxidant, anti-inflammatory, and anticancer activities of Euphorbia hirta ethanolic extract.

    PubMed

    Sharma, Neelesh; Samarakoon, Kalpa W; Gyawali, Rajendra; Park, Yang-Ho; Lee, Sung-Jin; Oh, Sung Jong; Lee, Tae-Hoon; Jeong, Dong Kee

    2014-01-01

    This study evaluated the chemical composition, antioxidant, anti-inflammatory and anticancer activities of a Euphorbia hirta L. extract. The antioxidant activities of whole E. hirta ethanol extract were determined by electron spin resonance spectrophotometric analysis of 1,1-diphenyl-2-picryl-hydrazyl (DPPH), hydroxyl, and alkyl radical levels and by using an online high-performance liquid chromatography (HPLC)-2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay. The E. hirta ethanol extract (0.5 mg/mL) exhibited DPPH-scavenging activity of 61.19% ± 0.22%, while the positive control (0.5 mg/mL ascorbic acid) had 100% ± 0.22% activity. The concentration of the extract required to trap 50% of DPPH (IC50) was 0.205 mg/mL. Online HPLC analysis of the extract also showed strong antioxidant activity. The anti-inflammatory activity of the E. hirta extract was assessed in lipopolysaccharide-induced RAW 264.7 macrophages. The anti-inflammatory activity was highest in the presence of 200 µg/mL E. hirta extract, and nitric oxide production was decreased significantly (p < 0.05). The extract also showed selective anticancer activity at a concentration of 100 µg/mL (p < 0.05). These results indicated that E. hirta may warrant further investigation for the development of antioxidant, anti-inflammatory, and anticancer herbal medications. PMID:25225720

  13. Coal extraction by aprotic dipolar solvents. Final report. [Tetramethylurea, hexa-methylphosphoramide

    SciTech Connect

    Sears, J T

    1985-12-01

    The overall goals of this project were to examine the rate and amount of extraction of coals at low temperature by a class of solvents with a generic structure to include tetramethylurea (TMU) and hexa-methylphosphoramide (HMPA) and to examine the nature of the extracted coal chemicals. The class of solvents with similar action, however, can be classified as aprotic, base solvents or, somewhat more broadly, specific solvents. The action of solvents by this last classification was then examined to postulate a mechanism of attack. Experimental work was conducted to explain the specific solvent attack including (1) pure solvent extraction, (2) extraction in mixtures with otherwise inert solvents and inhibitors, and (3) extraction with simultaneous catalytic enhancement attempts including water-gas shift conversion. Thus nuclear magnetic resonance (NMR) and gas-chromatograph mass spectrometer (GC-MS) analysis of extract molecules and extraction with high-pressure CO in TMU (plus 2% H2O) was performed. Effects of solvent additives such as cumene and quinone of large amounts of inert solvents such as tetralin, liminone, or carbon disulfide on extraction were also determined. Results are discussed. 82 refs., 36 figs., 37 tabs.

  14. Clamping instability and van der Waals forces in carbon nanotube mechanical resonators.

    PubMed

    Aykol, Mehmet; Hou, Bingya; Dhall, Rohan; Chang, Shun-Wen; Branham, William; Qiu, Jing; Cronin, Stephen B

    2014-05-14

    We investigate the role of weak clamping forces, typically assumed to be infinite, in carbon nanotube mechanical resonators. Due to these forces, we observe a hysteretic clamping and unclamping of the nanotube device that results in a discrete drop in the mechanical resonance frequency on the order of 5-20 MHz, when the temperature is cycled between 340 and 375 K. This instability in the resonant frequency results from the nanotube unpinning from the electrode/trench sidewall where it is bound weakly by van der Waals forces. Interestingly, this unpinning does not affect the Q-factor of the resonance, since the clamping is still governed by van der Waals forces above and below the unpinning. For a 1 ?m device, the drop observed in resonance frequency corresponds to a change in nanotube length of approximately 50-65 nm. On the basis of these findings, we introduce a new model, which includes a finite tension around zero gate voltage due to van der Waals forces and shows better agreement with the experimental data than the perfect clamping model. From the gate dependence of the mechanical resonance frequency, we extract the van der Waals clamping force to be 1.8 pN. The mechanical resonance frequency exhibits a striking temperature dependence below 200 K attributed to a temperature-dependent slack arising from the competition between the van der Waals force and the thermal fluctuations in the suspended nanotube. PMID:24758201

  15. Elastic scattering of Al25+p to explore the resonance structure in Si26

    NASA Astrophysics Data System (ADS)

    Jung, H. S.; Lee, C. S.; Kwon, Y. K.; Moon, J. Y.; Lee, J. H.; Yun, C. C.; Kim, M. J.; Hashimoto, T.; Yamaguchi, H.; Kahl, D.; Kubono, S.; Wakabayashi, Y.; Togano, Y.; Choi, Seonho; Kim, Y. H.; Kim, Y. K.; Park, J. S.; Kim, E. J.; Moon, C.-B.; Teranishi, T.; Iwasa, N.; Yamada, T.; Kato, S.; Cherubini, S.; Hayakawa, S.; Rapisarda, G. G.

    2014-09-01

    Background: The properties of resonances in Si26 are important to better constrain the Al25(p,?)Si26 reaction rate relevant to the synthesis of galactic Al26gs and energy generation in explosive stellar environment at higher temperature. Purpose: Al25+p elastic scattering was measured to further constrain and investigate disagreements in resonance parameters for the high-lying excited states of Si26 with high statistics and without background contamination within the target. Methods: The experiment was performed by bombarding a thick H2 target with an Al25 radioactive ion beam. The resonances at excitation energies of 6.6-8.3 MeV in the Si26 compound nucleus were studied at the low-energy radioactive-ion beam facility CRIB (Center for Nuclear Study Radioactive Ion Beam separator) at the University of Tokyo. Results: Six resonant states were observed and their resonance parameters were extracted by an R-matrix analysis. Our resonance parameters for two levels are in good agreement with the results of previous studies, while for four others, excitation energy, proton partial width, and spin-parity assignment disagree with the results of recent study via elastic scattering of Al25+p. Conclusion: The parameters of resonant states in Si26 determined in the present work for the Al25(p,?)Si26 reaction rate are consistent with that of the previous result, solving spin-parity assignment discrepancies between experiments, relevant at higher temperatures.

  16. Stochastic Resonance: from climate to biology

    E-print Network

    Roberto Benzi

    2007-02-05

    In this paper I will review some basic aspects of the mechanism of stochastic resonance. Stochastic resonance was first introduced as a possible mechanism to explain long term climatic variation. Since then, there have been many applications of stochastic resonance in physical and biological systems. I will show that in complex system, stochastic resonance can substantially change as a function of the ``system complexity''. Also, I will briefly mention how to apply stochastic resonance for the case of Brownian motors.

  17. Lattice QCD Evidence for Exotic Tetraquark Resonance

    E-print Network

    Hideo Suganuma; Kyosuke Tsumura; Noriyoshi Ishii; Fumiko Okiharu

    2005-11-04

    We study the manifestly exotic tetraquark D$_{\\rm s0}^{++}(cu\\bar s \\bar d)$ and the scalar tetraquark $f_0(ud \\bar u \\bar d)$ in SU(3)$_c$ anisotropic quenched lattice QCD with the $O(a)$-improved Wilson (clover) fermion with various quark masses including the idealized SU(4)$_f$ case. For $f_0(ud\\bar u \\bar d)$ etc., we only consider connected diagrams at the quenched level, i.e., the tetraquark $f_0(ud\\bar u\\bar d)$ is identical with D$_{\\rm s0}^{++} (cu\\bar s \\bar d)$ in the idealized SU(4)$_f$ case. First, for comparison, we study the lowest $q\\bar q$ scalar meson, and find that it has a large mass of about 1.37GeV after chiral extrapolation, which corresponds to $f_0(1370)$. Second, we investigate the lowest 4Q state in the spatial periodic boundary condition, and find that it is just a scattering state of two pseudoscalar mesons, as is expected. Third, to extract spatially-localized 4Q resonances, we use the Hybrid Boundary Condition (HBC) method, where anti-periodic and periodic boundary conditions are imposed on quarks ($c$,$u$) and antiquarks ($\\bar s$,$\\bar d$), respectively. By applying the HBC on a finite-volume lattice, the threshold of the two-meson scattering state is raised up, while the mass of a compact 4Q resonance is almost unchanged. In HBC, we find a nontrivial 4Q resonance state about 100 MeV below the two-meson threshold in some quark-mass region. Its chiral behavior largely differs from a two-meson scattering state. The scalar tetraquark $f_0(ud\\bar u\\bar d)$ is found to have the mass of about 1.1GeV after chiral extrapolation, and seems to correspond to $f_0(980)$. Then, the manifestly exotic tetraquark D$_{\\rm s0}^{++}(cu\\bar s \\bar d)$ would exist around 1GeV in the idealized SU(4)$_f$ chiral limit. Finally, MEM analysis is applied to obtain the spectral function of the 4Q system.

  18. COMPARING EXTRACTIONS OF SIVERS FUNCTIONS.

    SciTech Connect

    VOGELSANG, W.

    2005-09-07

    A comparison is given of the various recently published extractions of the Sivers functions from the HERMES and COMPASS data on single-transverse spin asymmetries in semi-inclusive deeply inelastic scattering.

  19. DNA Extraction & Staging Laboratory (DESL)

    Cancer.gov

    As part of the Cancer Genomics Research Laboratory (CGR), the DNA Extraction and Staging Laboratory (DESL) located in Frederick, MD, is responsible for the preparation of samples for investigators at NCI's Division of Cancer Epidemiology and Genetics (DCEG).

  20. Parallel algorithms for inductance extraction

    E-print Network

    Mahawar, Hemant

    2007-09-17

    of the iterative method becomes a challenging task. This work presents a class of parallel algorithms for fast and accurate inductance extraction of VLSI circuits. We use the solenoidal basis approach that converts the linear system into a reduced system...

  1. Extracting information from informal communication

    E-print Network

    Rennie, Jason D. M. (Jason Daniel Malyutin), 1976-

    2007-01-01

    This thesis focuses on the problem of extracting information from informal communication. Textual informal communication, such as e-mail, bulletin boards and blogs, has become a vast information resource. However, such ...

  2. Graph-cut energy minimization for object extraction in MRCP medical images.

    PubMed

    Logeswaran, Rajasvaran; Kim, Dongho; Kim, Jungwhan; Jung, Keechul; Song, Bundo

    2012-02-01

    Bile duct identification and extraction in magnetic resonance cholangiopancreatography (MRCP) images, is a necessary step in the development of computer-aided diagnosis systems using such images. MRCP is becoming the de facto modality in the diagnosis of biliary diseases and even in the pre-surgical workup for liver transplants. The energy minimization graph-cut method is a proven technique in the extraction of objects in natural images, and even used in 3D reconstruction. This paper proposes several versions of the graph-cut approach for the extraction of the biliary structures in MRCP images. The schemes include a fully interactive lazy snapping method, a manual point selection method for minimal user interaction and an automated phase unwrapping via max flows (PUMA) implementation. The performance of the algorithms vary, but the results support that the scheme is a promising semi-automated object extraction scheme for the significant biliary structures in medical MRCP images. PMID:20703717

  3. Hub4 Information Extraction Evaluation

    Microsoft Academic Search

    David S. Pallett; John S. Garofolo; Jonathan G. Fiscus; Mark A. Przybocki

    1998-01-01

    This paper documents the Information Extraction Named-EntityEvaluation (IE-NE), one of the new spokes added to theDARPA-sponsored 1998 Hub-4 Broadcast News Evaluation.This paper discusses the information extraction task as posedfor the 1998 Broadcast News Evaluation. This paper reviewsthe evaluation metrics, the scoring process, and the test corpusthat was used for the evaluation. Finally, this paper reviews theresults of the first running

  4. Extraction of silicones from soil

    Microsoft Academic Search

    Robert G. Lehmann

    1993-01-01

    Silicone polymer, polydimethylsiloxane (PDMS), was extracted from soil incubated at 100 mg kg[sup [minus]1] for 0,1,3,7,14, and 28 d with mean recovery of 95.4% ([sigma] = 2.1%). From four agricultural soils incubated for one week at 1, 10, and 100 mg kg[sup [minus]1], mean extraction recovery was 95.6% ([sigma] = 3.2%). The method is now being used in [sup 14]C

  5. Point Source Extraction with MOPEX

    E-print Network

    David Makovoz; Francine R. Marleau

    2005-06-30

    MOPEX (MOsaicking and Point source EXtraction) is a package developed at the Spitzer Science Center for astronomical image processing. We report on the point source extraction capabilities of MOPEX. Point source extraction is implemented as a two step process: point source detection and profile fitting. Non-linear matched filtering of input images can be performed optionally to increase the signal-to-noise ratio and improve detection of faint point sources. Point Response Function (PRF) fitting of point sources produces the final point source list which includes the fluxes and improved positions of the point sources, along with other parameters characterizing the fit. Passive and active deblending allows for successful fitting of confused point sources. Aperture photometry can also be computed for every extracted point source for an unlimited number of aperture sizes. PRF is estimated directly from the input images. Implementation of efficient methods of background and noise estimation, and modified Simplex algorithm contribute to the computational efficiency of MOPEX. The package is implemented as a loosely connected set of perl scripts, where each script runs a number of modules written in C/C++. Input parameter setting is done through namelists, ASCII configuration files. We present applications of point source extraction to the mosaic images taken at 24 and 70 micron with the Multiband Imaging Photometer (MIPS) as part of the Spitzer extragalactic First Look Survey and to a Digital Sky Survey image. Completeness and reliability of point source extraction is computed using simulated data.

  6. Production of large area low-energy electron beams by extraction from a multidipolar plasma (abstract)

    SciTech Connect

    Lacoste, A.; Bechu, S.; Maulat, O.; Pelletier, J.; Arnal, Y. [Laboratoire de Physique Subatomique et de Cosmologie - UJF, CNRS IN2P3 et ST2I, INPG, Centre de Recherche Plasmas-Materiaux-Nanostructures, 53 rue des Martyrs, 38026 Grenoble, Cedex (France)

    2008-02-15

    The production of large area low-energy electron beams by extraction from a low-pressure plasma is investigated. In order to extract electron beams of given energy from a plasma, the plasma potential, as referred to wall potential, must be stationary and independent of the extraction potential. The macroscopic neutrality of the plasma therefore requires that reactor walls are metallic and that extraction to reactor wall area ratio is less than the square root of the electron to ion mass ratio. These specifications are fulfilled in the source presented in this study where the plasma is produced in a cylindrical chamber by seven elementary dipolar sources distributed over the end flange of a cylindrical chamber opposite to the extraction grid. The plasma is sustained at electron cyclotron resonance by microwaves at 2.45 GHz in the chamber whose wall potential (extraction potential) can be varied from 0 to -200 V with respect to the ground potential. The electron beam extracted from the plasma through the grid then expands in a second chamber whose walls are set at the ground potential. The details of the experimental arrangement built on the above specifications are presented and the characteristics of argon plasmas measured by using cylindrical Langmuir probes as a function of the extraction voltage. In the same way, electron beam characteristics in the ground potential chamber are also measured using both planar and cylindrical Langmuir probes. In particular, variations in plasma and beam potentials are simultaneously determined as a function of extraction voltage. Current-voltage extraction characteristics are also reported, which show that electron beams in the ampere range can be extracted between 0 and -200 V. The experimental results are in good agreement with the expected electron source behavior.

  7. Molecular magnetic resonance imaging

    PubMed Central

    Hengerer, A; Grimm, J

    2006-01-01

    Molecular MRI (mMRI) is a special implementation of Molecular Imaging for the non-invasive visualisation of biological processes at the cellular and molecular level. More specifically, mMRI comprises the contrast agent-mediated alteration of tissue relaxation times for the detection and localisation of molecular disease markers (such as cell surface receptors, enzymes or signaling molecules), cells (e.g. lymphocytes, stem cells) or therapeutic drugs (e.g. liposomes, viral particles). MRI yields topographical, anatomical maps; functional MRI (fMRI) provides rendering of physiologic functions and magnetic resonance spectroscopy (MRS) reveals the distribution patterns of some specific metabolites. mMRI provides an additional level of information at the molecular or cellular level, thus extending MRI further beyond the anatomical and physiological level. These advances brought by mMRI are mandatory for MRI to be competitive in the age of molecular medicine. mMRI is already today increasingly used for research purposes, e.g. to facilitate the examination of cell migration, angiogenesis, apoptosis or gene expression in living organisms. In medical diagnostics, mMRI will pave the way toward a significant improvement in early detection of disease, therapy planning or monitoring of outcome and will therefore bring significant improvement in the medical treatment for patients. In general, Molecular Imaging demands high sensitivity equipment, capable of quantitative measurements to detect probes that interact with targets at the pico- or nanomolar level. The challenge to detect such sparse targets can be exemplified with cell surface receptors, a common target for molecular imaging. At high expression levels (bigger than 106 per cell) the receptor concentration is approx. 1015 per ml, i.e. the concentration is in the micromole range. Many targets, however, are expressed in even considerably lower concentrations. Therefore the most sensitive modalities, namely nuclear imaging (PET and SPECT) have always been at the forefront of Molecular Imaging, and many nuclear probes in clinical use today are already designed to detect molecular mechanisms (such as FDG, detecting high glucose metabolism). In recent years however, Molecular Imaging has commanded attention from beyond the field of nuclear medicine. Further imaging modalities to be considered for molecular imaging primarily include optical imaging, MRI and ultrasound. PMID:21614236

  8. Reverse resonance and stochastic resonance in intracellular calcium oscillations

    NASA Astrophysics Data System (ADS)

    Duan, Wei-Long; Long, Fei; Li, Chun

    2014-05-01

    The roles of time delay on the coherence resonance are investigated in the intracellular calcium oscillation system described by the processes of active and passive transport of intracellular Ca2+ driven by colored noises. From the numerical simulation of the reciprocal coefficient of variance of interspike intervals of calcium spikes by the method of second-order algorithm, the results indicate that: (i) The stochastic or reverse synchronization is induced by a certain value of time delay or correlation time; (ii) A phenomenon of reverse resonance can be obtained in the function of reciprocal coefficient of variance vs. time delay or vs. strength of noises as time delay increases; (iii) Both stochastic and reverse resonance are observed in the function of reciprocal coefficient of variance vs. correlation time with varying strength of noises.

  9. High rejection, tunable parallel resonance in micromachined lead zirconate titanate on silicon resonators

    E-print Network

    Afshari, Ehsan

    High rejection, tunable parallel resonance in micromachined lead zirconate titanate on silicon; published online 9 September 2011) This paper presents a micromachined lead zirconate titanate-film lead zirconate titanate (PZT) resonator work,10 where improved series resonance motional resistance

  10. Extractant composition including crown ether and calixarene extractants

    DOEpatents

    Meikrantz, David H. (Idaho Falls, ID); Todd, Terry A. (Aberdeen, ID); Riddle, Catherine L. (Idaho Falls, ID); Law, Jack D. (Pocalello, ID); Peterman, Dean R. (Idaho Falls, ID); Mincher, Bruce J. (Idaho Falls, ID); McGrath, Christopher A. (Blackfoot, ID); Baker, John D. (Blackfoot, ID)

    2009-04-28

    An extractant composition comprising a mixed extractant solvent consisting of calix[4] arene-bis-(tert-octylbenzo)-crown-6 ("BOBCalixC6"), 4',4',(5')-di-(t-butyldicyclo-hexano)-18-crown-6 ("DtBu18C6"), and at least one modifier dissolved in a diluent. The DtBu18C6 may be present at from approximately 0.01M to approximately 0.4M, such as at from approximately 0.086 M to approximately 0.108 M. The modifier may be 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol ("Cs-7SB") and may be present at from approximately 0.01M to approximately 0.8M. In one embodiment, the mixed extractant solvent includes approximately 0.15M DtBu18C6, approximately 0.007M BOBCalixC6, and approximately 0.75M Cs-7SB modifier dissolved in an isoparaffinic hydrocarbon diluent. The extractant composition further comprises an aqueous phase. The mixed extractant solvent may be used to remove cesium and strontium from the aqueous phase.

  11. The Regge-plus-resonance model for kaon production on the proton and the neutron

    E-print Network

    J. Ryckebusch; L. De Cruz; P. Vancraeyveld; T. Vrancx

    2011-07-29

    The Regge-plus-resonance (RPR) framework for kaon photoproduction on the proton and the neutron is an economical single-channel model with very few parameters. Not only does the RPR model allow one to extract resonance information from the data, it has predictive power. As an example we show that the RPR model makes fair predictions for the $p(e,e'K^{+})\\Lambda$ and the $n(\\gamma,K^{+})\\Sigma ^{-}$ observables starting from amplitudes optimized for the reaction $p(\\gamma, K ^{+})\\Lambda$ and $p(\\gamma,K^{+})\\Sigma ^{0}$ respectively.

  12. INEX modeling of the Boeing ring optical resonator free-electron laser

    SciTech Connect

    Goldstein, J.C.; Tokar, R.L.; McVey, B.D.; Elliott, C.J. (Los Alamos National Lab., NM (USA)); Dowell, D.H.; Laucks, M.L.; Lowrey, A.R. (Boeing Aerospace and Electronics Co., Seattle, WA (USA))

    1990-01-01

    We present new results from the integrated numerical model of the accelerator/beam transport system and ring optical resonator of the Boeing free-electron laser experiment. Modifications of the electron-beam transport have been included in a previously developed PARMELA model and are shown to reduce dramatically emittance growth in the 180{degree} bend. The new numerically generated electron beam is used in the 3-D FEL simulation code FELEX to calculate expected laser characteristics with the ring optical resonator and the 5-m untapered THUNDER wiggler. Gain, extraction efficiency, and optical power are compared with experimental data. Performance sensitivity to optical cavity misalignments is studied.

  13. The Giant Monopole Resonance in the Sn Isotopes: Why is Tin so "Fluffy"?

    E-print Network

    U. Garg

    2006-08-03

    The isoscalar giant monopole resonance (GMR) has been investigated in a series of Sn isotopes (A=112--124) using inelstic scattering of 400-MeV alpha particles at extremely forward angles (including 0deg). The primary aim of the investigation has been to explore the role of the "symmetry-energy" term in the expression for nuclear incompressibility. It is found that the energies of the GMR in the Sn isotopes are significantly lower than those expected from the nuclear incompressibility previously extracted from the available data on the compressional-mode giant resonances.

  14. Anti-resonance mixing filter

    NASA Technical Reports Server (NTRS)

    Evans, Paul S. (Inventor)

    2001-01-01

    In a closed loop control system that governs the movement of an actuator a filter is provided that attenuates the oscillations generated by the actuator when the actuator is at a resonant frequency. The filter is preferably coded into the control system and includes the following steps. Sensing the position of the actuator with an LVDT and sensing the motor position where motor drives the actuator through a gear train. When the actuator is at a resonant frequency, a lag is applied to the LVDT signal and then combined with the motor position signal to form a combined signal in which the oscillation generated by the actuator are attenuated. The control system then controls ion this combined signal. This arrangement prevents the amplified resonance present on the LVDT signal, from causing control instability, while retaining the steady state accuracy associated with the LVDT signal. It is also a characteristic of this arrangement that the signal attenuation will always coincide with the load resonance frequency of the system so that variations in the resonance frequency will not effectuate the effectiveness of the filter.

  15. Optically induced parametric magnetic resonances

    NASA Astrophysics Data System (ADS)

    Jimenez, Ricardo; Knappe, Svenja; Kitching, John

    2011-05-01

    Optically pumped vector magnetometers based on zero-field resonances have reached very high sensitivities by operating at high atomic densities where dephasing due to spin-exchange collisions can be suppressed. Simplified setups, with just one laser beam have measured magnetic fields from the human brain and heart. A key feature in these magnetometers is the introduction of an rf magnetic field along the measurement axis to generate a parametric resonance. Lock-in detection of the transmitted light, at an odd harmonic of the modulation frequency, allows the reduction of the low frequency noise and generates a resonance with dispersive shape. Here we study a zero-field vector magnetometer where the parametric resonances are induced by the vector AC stark-shift of light. This approach does not produce any external magnetic field that could disturb the reading of other magnetometers in the vicinity and could provide an alternative in applications where an applied AC-field cannot be used. We have characterized the vector AC stark-shift effect of light on Rb atoms contained in a micromachined vapor cell with buffer gas. We have obtained parametric resonances induced by modulation of the light-shift. We also analyze the detunings and intensities of the light-shift beam that maintain the magnetometer within the spin-exchange relaxation-free regime.

  16. Turn-By Beam Extraction during Acceleration in a Synchrotron

    NASA Astrophysics Data System (ADS)

    Tsoupas, Nicholaos; Trbojevic, Dejan

    2014-02-01

    A synchrotron to accelerate protons or carbon ions for medical applications is being designed at Brookhaven National Laboratory (BNL). Single beam bunches with maximum beam energy of 1.18 GeV and 400 MeV/u for protons and carbon ions respectively will be extracted from the synchrotron at 15 Hz. For protons, the maximum required energy for irradiating a tumor is ˜206 MeV. A pencil-like proton beam containing ˜5.4×107 p/bunch delivers a therapeutic dose of 2.5 Gy in ˜1.5 minutes to treat a tumor of 1 liter volume. It will take ˜80 minutes with bunches containing 4.5×104 ions/bunch to deliver the same dose of 2.5 Gy with a 400 MeV/u pencil-like carbon beam. This extended treatment time when using carbon ions is not acceptable. In addition, the synchrotron cannot be controlled with a beam bunch containing such a low number of carbon ions. To overcome these two problems of the extended treatment time and the low bunch intensity required for the treatment when carbon ions are used, we have devised a method to “peel” the required 4.5×104 carbon-ions/bunch from the accelerating carbon beam bunch containing ˜108 ions/bunch and deliver them to the tumor on a “turn-by-turn” basis. Unlike other methods of beam extraction from a synchrotron, such as resonance extraction, this method does not allow for any beam losses during the extraction and the carbon beam can be peeled off in less than 15 ms during the acceleration or deceleration cycle of the synchrotron. Thus, this turn-by-turn beam extraction method provides beam with variable energy and precisely controlled beam current during the 30 ms acceleration or deceleration time.

  17. Cesium and strontium extraction using a mixed extractant solvent including crown ether and calixarene extractants

    DOEpatents

    Meikrantz, David H. (Idaho Falls, ID); Todd, Terry A. (Aberdeen, ID); Riddle, Catherine L. (Idaho Falls, ID); Law, Jack D. (Pocatello, ID); Peterman, Dean R. (Idaho Falls, ID); Mincher, Bruce J. (Idaho Falls, ID); McGrath, Christopher A. (Blackfoot, ID); Baker, John D. (Blackfoot, ID)

    2007-11-06

    A mixed extractant solvent including calix[4]arene-bis-(tert-octylbenzo)-crown-6 ("BOBCalixC6"), 4',4',(5')-di-(t-butyldicyclo-hexano)-18-crown-6 ("DtBu18C6"), and at least one modifier dissolved in a diluent. The mixed extractant solvent may be used to remove cesium and strontium from an acidic solution. The DtBu18C6 may be present from approximately 0.01 M to approximately 0.4M, such as from approximately 0.086 M to approximately 0.108 M. The modifier may be 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol ("Cs-7SB") and may be present from approximately 0.01M to approximately 0.8M. In one embodiment, the mixed extractant solvent includes approximately 0.15M DtBu18C6, approximately 0.007M BOBCalixC6, and approximately 0.75M Cs-7SB modifier dissolved in an isoparaffinic hydrocarbon diluent. The mixed extractant solvent may form an organic phase in an extraction system that also includes an aqueous phase. Methods of extracting cesium and strontium as well as strontium alone are also disclosed.

  18. Lattice QCD Evidence for Exotic Tetraquark Resonance

    E-print Network

    Suganuma, H; Ishii, N; Okiharu, F; Suganuma, Hideo; Tsumura, Kyosuke; Ishii, Noriyoshi; Okiharu, Fumiko

    2005-01-01

    We study the manifestly exotic tetraquark D$_{\\rm s0}^{++}(cu\\bar s \\bar d)$ and the scalar tetraquark $f_0(ud \\bar u \\bar d)$ in SU(3)$_c$ anisotropic quenched lattice QCD with the $O(a)$-improved Wilson (clover) fermion with various quark masses including the idealized SU(4)$_f$ case. For $f_0(ud\\bar u \\bar d)$ etc., we only consider connected diagrams at the quenched level, i.e., the tetraquark $f_0(ud\\bar u\\bar d)$ is identical with D$_{\\rm s0}^{++} (cu\\bar s \\bar d)$ in the idealized SU(4)$_f$ case. First, for comparison, we study the lowest $q\\bar q$ scalar meson, and find that it has a large mass of about 1.37GeV after chiral extrapolation, which corresponds to $f_0(1370)$. Second, we investigate the lowest 4Q state in the spatial periodic boundary condition, and find that it is just a scattering state of two pseudoscalar mesons, as is expected. Third, to extract spatially-localized 4Q resonances, we use the Hybrid Boundary Condition (HBC) method, where anti-periodic and periodic boundary conditions ar...

  19. Effect of feature extraction for brain tumor classification based on short echo time 1H MR spectra

    Microsoft Academic Search

    J. Luts; J. B. Poullet; J. M. Garcia-Gomez; A. Heerschap; M. Robles; J. A. Suykens; S. van Huffel

    2008-01-01

    This study examines the effect of feature extraction methods prior to automated pattern recognition based on magnetic resonance spectroscopy (MRS) for brain tumor diagnosis. Since individual inspection of spectra is time-consuming and requires specific spectroscopic expertise, the introduction of clinical decision support systems (DSSs) is expected to strongly promote the clinical use of MRS. This study focuses on the feature

  20. Electrostatic septa design and performance for injection and extraction to and from the MIT-Bates South Hall Ring (SHR)

    Microsoft Academic Search

    S. Sobczynski; R. Averill; M. Farkhondeh; J. Flanz; C. Sibley

    1993-01-01

    The MIT-Bates South Hall Ring (SHR) is an election storage ring undergoing commissioning. Electrostatic septa are used to inject electrons into and resonantly extract electrons from the ring. This report describes the engineering design and performance achieved for 2 electrostatic septa constructed with 270, 50 micron thick, 5 mm wide molybdenum foils stretched over a long precision machined, C-shaped carrier.

  1. Supercritical Fluid Chromatography, Pressurized Liquid Extraction and Supercritical Fluid Extraction

    SciTech Connect

    Henry, Matthew C.; Yonker, Clement R.

    2006-06-15

    In this review we examine the related fields of supercritical fluid chromatography (SFC) and supercritical fluid extraction (SFE). We reviewed the published literature in the period from November 2003 to November 2005. Well over 300 papers were published in this period. This large body of work indicates continuing active growth of the field, but an exhaustive review is beyond the scope of this work. We have chosen to include a sampling of publications that best represent the continuing trends and new ideas in the field. In keeping with past reviews on this subject1, we have broadened our scope to include fluid systems operating at high temperature and pressure, but below the critical point. Various terms have been applied to this state: sub-critical fluid extraction, pressurized liquid extraction, and accelerated solvent extraction. The term accelerated solvent extraction has been used by instrument manufacturers to refer to this process, but we will use the more descriptive term pressurized liquid extraction (PLE) to refer to these systems. Most of the research in the field is of an “evolutionary” rather than “revolutionary” nature. As in the previous review period, applications papers make up a majority of the published work. Pharmaceutical applications continue to be a strong theme. Most of the pharmaceutical work has centered on preparative, rather than analytical, separations. Chiral separations are an exception, as analytical scale separations of chiral compounds are an area of intense interest. Food and natural products represent the next largest body of work. Major themes are the isolation and characterization of high-value added foodstuffs, fragrances, and flavor compounds from novel natural materials or agricultural by-products. The areas of food, natural products, and pharmaceutical separation science converge in the area of so-called nutraceuticals. These are typically high-value products, either sold alone or as part of a fortified food, that are regulated as food supplements but are intended to treat disease or maintain health. Antioxidants and beneficial lipid products are major examples in this category. The final major category consists of environmental applications, both as an extraction technique for environmental analysis, and as a possible remediation strategy for removing contaminants that would otherwise be too expensive to recover. Most of the work in this area has focused on non-polar compounds, such as polyaromatic hydrocarbons (PAHs) and poly-chlorinated biphenyls (PCB’s), where non-polar supercritical (SC) CO2 offers high extraction efficiencies. Co-solvent systems combining CO2 with one or more modifiers extend the utility of SC CO2 to polar and even ionic compounds. Supercritical water can extract polar compounds, and it has the additional advantage of combining extraction and destruction of contaminants via the supercritical water oxidation (SUWOX) process. Supercritical fluids are also useful in various niche applications. Fuel extraction, conversion, and analysis is one such application. Extraction of metals from various matrixes is also an area of continuing interest. The application of supercritical fluid (SCF) technology to production of nano-structured materials is a new area likely to see rapid growth in the next few years.

  2. Viscoelastic coupling of nanoelectromechanical resonators.

    SciTech Connect

    Simonson, Robert Joseph; Staton, Alan W.

    2009-09-01

    This report summarizes work to date on a new collaboration between Sandia National Laboratories and the California Institute of Technology (Caltech) to utilize nanoelectromechanical resonators designed at Caltech as platforms to measure the mechanical properties of polymeric materials at length scales on the order of 10-50 nm. Caltech has succeeded in reproducibly building cantilever resonators having major dimensions on the order of 2-5 microns. These devices are fabricated in pairs, with free ends separated by reproducible gaps having dimensions on the order of 10-50 nm. By controlled placement of materials that bridge the very small gap between resonators, the mechanical devices become coupled through the test material, and the transmission of energy between the devices can be monitored. This should allow for measurements of viscoelastic properties of polymeric materials at high frequency over short distances. Our work to date has been directed toward establishing this measurement capability at Sandia.

  3. Resonance structure of ?--->K-?+?-?? decays

    NASA Astrophysics Data System (ADS)

    Asner, D. M.; Eppich, A.; Gronberg, J.; Hill, T. S.; Lange, D. J.; Morrison, R. J.; Briere, R. A.; Behrens, B. H.; Ford, W. T.; Gritsan, A.; Roy, J.; Smith, J. G.; Alexander, J. P.; Baker, R.; Bebek, C.; Berger, B. E.; Berkelman, K.; Blanc, F.; Boisvert, V.; Cassel, D. G.; Dickson, M.; Drell, P. S.; Ecklund, K. M.; Ehrlich, R.; Foland, A. D.; Gaidarev, P.; Galik, R. S.; Gibbons, L.; Gittelman, B.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Hopman, P. I.; Jones, C. D.; Kreinick, D. L.; Lohner, M.; Magerkurth, A.; Meyer, T. O.; Mistry, N. B.; Ng, C. R.; Nordberg, E.; Patterson, J. R.; Peterson, D.; Riley, D.; Thayer, J. G.; Thies, P. G.; Valant-Spaight, B.; Warburton, A.; Avery, P.; Prescott, C.; Rubiera, A. I.; Yelton, J.; Zheng, J.; Brandenburg, G.; Ershov, A.; Gao, Y. S.; Kim, D. Y.-J.; Wilson, R.; Browder, T. E.; Li, Y.; Rodriguez, J. L.; Yamamoto, H.; Bergfeld, T.; Eisenstein, B. I.; Ernst, J.; Gladding, G. E.; Gollin, G. D.; Hans, R. M.; Johnson, E.; Karliner, I.; Marsh, M. A.; Palmer, M.; Plager, C.; Sedlack, C.; Selen, M.; Thaler, J. J.; Williams, J.; Edwards, K. W.; Janicek, R.; Patel, P. M.; Sadoff, A. J.; Ammar, R.; Bean, A.; Besson, D.; Davis, R.; Kravchenko, I.; Kwak, N.; Zhao, X.; Anderson, S.; Frolov, V. V.; Kubota, Y.; Lee, S. J.; Mahapatra, R.; O'neill, J. J.; Poling, R.; Riehle, T.; Smith, A.; Urheim, J.; Ahmed, S.; Alam, M. S.; Athar, S. B.; Jian, L.; Ling, L.; Mahmood, A. H.; Saleem, M.; Timm, S.; Wappler, F.; Anastassov, A.; Duboscq, J. E.; Gan, K. K.; Gwon, C.; Hart, T.; Honscheid, K.; Hufnagel, D.; Kagan, H.; Kass, R.; Pedlar, T. K.; Schwarthoff, H.; Thayer, J. B.; von Toerne, E.; Zoeller, M. M.; Richichi, S. J.; Severini, H.; Skubic, P.; Undrus, A.; Chen, S.; Fast, J.; Hinson, J. W.; Lee, J.; Menon, N.; Miller, D. H.; Shibata, E. I.; Shipsey, I. P.; Pavlunin, V.; Cronin-Hennessy, D.; Kwon, Y.; Lyon, A. L.; Thorndike, E. H.; Jessop, C. P.; Marsiske, H.; Perl, M. L.; Savinov, V.; Ugolini, D.; Zhou, X.; Coan, T. E.; Fadeyev, V.; Maravin, Y.; Narsky, I.; Stroynowski, R.; Ye, J.; Wlodek, T.; Artuso, M.; Ayad, R.; Boulahouache, C.; Bukin, K.; Dambasuren, E.; Karamov, S.; Kopp, S.; Majumder, G.; Moneti, G. C.; Mountain, R.; Schuh, S.; Skwarnicki, T.; Stone, S.; Viehhauser, G.; Wang, J. C.; Wolf, A.; Wu, J.; Csorna, S. E.; Danko, I.; McLean, K. W.; Márka, Sz.; Xu, Z.; Godang, R.; Kinoshita, K.; Lai, I. C.; Schrenk, S.; Bonvicini, G.; Cinabro, D.; Perera, L. P.; Zhou, G. J.; Eigen, G.; Lipeles, E.; Schmidtler, M.; Shapiro, A.; Sun, W. M.; Weinstein, A. J.; Würthwein, F.; Jaffe, D. E.; Masek, G.; Paar, H. P.; Potter, E. M.; Prell, S.; Sharma, V.

    2000-10-01

    Using a sample of 4.7 fb-1 integrated luminosity accumulated with the CLEO II detector at the Cornell Electron Storage Ring (CESR), we investigate the mass spectrum and resonant structure in ?--->K-?+?-?? decays. We measure the relative fractions of K1(1270) and K1(1400) resonances in these decays, as well as the K1 masses and widths. Our fitted K1 resonances are somewhat broader than previous hadroproduction measurements, and in agreement with recent CERN LEP results from tau decay. The larger central value of our measured width supports models which attribute the small ?--->K-?+?-?? branching fraction to larger K1 widths than are presently tabulated. We also determine the Ka-Kb mixing angle ?K.

  4. Two-photon resonance fluorescence

    SciTech Connect

    Alexanian, Moorad; Bose, Subir K. [Department of Physics and Physical Oceanography, University of North Carolina Wilmington, Wilmington, North Carolina 28403 (United States); Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States)

    2006-12-15

    We present a theory of two-photon resonance fluorescence of an atom or molecule in which the excitation by an external electromagnetic field as well as fluorescence emission is mediated by two-photon processes. The treatment is based on first dressing the atom or molecule by the external field and then evaluating perturbatively the effect of the interaction with the vacuum or fluorescent field and so resonance fluorescence can be considered as spontaneous emission from the dressed atom. The introduction of the combined system of atom and external field via dressed states leads to simpler calculations and more transparent physics. The fluorescence spectrum derived by us has similarities as well as differences with that of one-photon resonance fluorescence and earlier theoretical predictions for the two-photon case.

  5. Photon Localization in Resonant Media

    NASA Astrophysics Data System (ADS)

    Genack, Azriel

    2002-03-01

    Unlike electrons that can be trapped by the Coulomb interaction at atomic sites, photons are not bound by individual particles. They may, however, be strongly scattered at Mie resonances, with the scattering cross section considerably exceeding the geometric cross section. We utilize Mie resonances to localize microwave radiation in low-density quasi-one dimensional samples of randomly positioned dielectric spheres. We explore factors that facilitate photon localization and probe the properties of localized waves. Sharp dips in the ensemble average of transmission and peaks in the average photon transit time are found near the first five Mie resonances. A decisive statistical test of photon localization, based on measurements of the variance of the intensity normalized by its ensemble average value, shows, however, that localization occurs only in a narrow window above the first Mie resonance. Measurements of this localization parameter are compared to measurements of the dimensionless conductance and of the Thouless number in samples with and without absorption. The Thouless number, which is the ratio of the width to the spacing of quasi-modes of a random medium, is obtained from measurements of the field correlation function with frequency shift and of the spacing between resonances in a sealed cavity. In samples with negligible absorption, these parameters coincide. The localization parameters reach a minimum within the window of localization as a result of collective scattering. In the presence of absorption, only the variance of intensity remains a reliable guide to localization. When the sample is cooled to 77 K to reduce absorption, narrow Lorentzian transmission peaks are observed as a result of resonant tunneling through long-lived localized modes. The enhancement of intensity in long-lived modes as the localization threshold is approached is related to sharp line lasing in random amplifying media. In collaboration with Andrey Chabanov.

  6. Resonant transfer excitation: Interference effects

    SciTech Connect

    Shafroth, S.M. [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy; Benhenni, M. [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy]|[Toulouse-3 Univ., 31 (France). Lab. de Decharges dans les Gaz; Swenson, J.K. [Oak Ridge National Lab., TN (United States)]|[Lawrence Livermore National Lab., CA (United States); Schulz, M. [Oak Ridge National Lab., TN (United States)]|[Missouri Univ., Rolla, MO (United States). Dept. of Physics; Giese, J.P.; Schone, H. [Oak Ridge National Lab., TN (United States)]|[Kansas State Univ., Manhattan, KS (United States). Dept. of Physics; Vane, C.R.; Dittner, P.F.; Datz, S. [Oak Ridge National Lab., TN (United States)

    1991-12-31

    Interference effects in RTE (Resonant Transfer Excitation) can be studied for low Z projectiles via Auger electrons emitted from highly ionized fast moving projectile ions following collisions with low Z targets. RTE in ion-atom collisions is closely related to dielectronic recombination. In the latter case which is of practical interest to the fusion power program an electron with the proper velocity incident on a highly charged ion is resonantly captured and simultaneously interacts with an inner shell electron to excite it, thus forming a doubly excited state which may decay predominantly by X-ray emission for higher Z ions or by Auger electron decay for lower Z ions. The resonant velocity is that of the Auger electron emitted by the ion in the doubly excited state in RTE the electrons to be captured are in low Z atomic (typically He) or Molecular (typically H{sub 2}) targets and the ions are produced by accelerators in highly charged states with the appropriate resonant velocity. The resonance is much broadened by the velocity distribution of the target electrons. Thus the resonance width as a function of projectile energy is determined by folding the Compton profile of the target electrons with the dielectronic recombination cross sections. A weaker effect and more speculative is Two Electron Transfer Excitation. Here one target electron excites the projectile 1s electron to the 2p shell for example and the other target electron is captured to an excited state of the projectile. This effect becomes more important at projectile energies higher than the energy where the RTE cross section has its maximum value. The electron--electron interaction has been beautifully demonstrated by Zouros et al. Finally, there might be interference with shakeup. This paper will present angular distribution measurements of Auger lines so that the effects of interference between these various processes can be studied.

  7. Resonant transfer excitation: Interference effects

    SciTech Connect

    Shafroth, S.M. (North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy); Benhenni, M. (North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy Toulouse-3 Univ., 31 (France). Lab. de Decharges dans les Gaz); Swenson, J.K. (Oak Ridge National Lab., TN (United States) Lawrence Livermore National Lab., CA (United States)); Schulz, M. (Oak R

    1991-01-01

    Interference effects in RTE (Resonant Transfer Excitation) can be studied for low Z projectiles via Auger electrons emitted from highly ionized fast moving projectile ions following collisions with low Z targets. RTE in ion-atom collisions is closely related to dielectronic recombination. In the latter case which is of practical interest to the fusion power program an electron with the proper velocity incident on a highly charged ion is resonantly captured and simultaneously interacts with an inner shell electron to excite it, thus forming a doubly excited state which may decay predominantly by X-ray emission for higher Z ions or by Auger electron decay for lower Z ions. The resonant velocity is that of the Auger electron emitted by the ion in the doubly excited state in RTE the electrons to be captured are in low Z atomic (typically He) or Molecular (typically H{sub 2}) targets and the ions are produced by accelerators in highly charged states with the appropriate resonant velocity. The resonance is much broadened by the velocity distribution of the target electrons. Thus the resonance width as a function of projectile energy is determined by folding the Compton profile of the target electrons with the dielectronic recombination cross sections. A weaker effect and more speculative is Two Electron Transfer Excitation. Here one target electron excites the projectile 1s electron to the 2p shell for example and the other target electron is captured to an excited state of the projectile. This effect becomes more important at projectile energies higher than the energy where the RTE cross section has its maximum value. The electron--electron interaction has been beautifully demonstrated by Zouros et al. Finally, there might be interference with shakeup. This paper will present angular distribution measurements of Auger lines so that the effects of interference between these various processes can be studied.

  8. Antimicrobial effect of rosemary extracts.

    PubMed

    Del Campo, J; Amiot, M J; Nguyen-The, C

    2000-10-01

    A rosemary extract commercially exploited (Oxy'less) as an antioxidant of lipids in foods was dissolved in ethanol (100 mg/ml), and the solution was tested against foodborne microorganisms. For gram-positive bacteria, the MIC of the ethanolic solution was 1% for Leuconostoc mesenteroides, 0.5% for Listeria monocytogenes, 0.5% for Staphylococcus aureus, 0.13% for Streptococcus mutans, and 0.06% for Bacillus cereus. It slowed the growth of Penicillium roquefortii and Botrytis cinerea. Up to 1% of the ethanolic solution had no activity on the gram-negative bacteria Escherichia coli, Salmonella Enteritidis, and Erwinia carotovora and on the yeasts Rhodotorula glutinis and Cryptococcus laurentii. Antibacterial activity of the rosemary extract was strongly influenced by the composition of the media. The MIC was reduced by low pH, high NaCl contents, and low temperatures. Low pH and high NaCl concentration had a synergistic effect on the MIC of the rosemary extract for S. aureus. Lipids, surface-active agents, and some proteins decreased its antibacterial activity, whereas pectin had no effect. The inhibitory effect was little modified by heat treatment (100 degrees C). The natural microflora of pasteurized zucchini broth was inhibited by 0.5% of the rosemary extract. The antibacterial activity was linked to the compounds extracted with hexane, which are presumably phenolic diterpenoids. PMID:11041135

  9. Three-dimensional feature extraction

    NASA Astrophysics Data System (ADS)

    Kuan, D.

    1983-06-01

    Range images offer significant advantages over passive reflectance images because they preserve the 3-D information of the scene viewed from the sensor. Therefore, range data is becoming an increasingly important source of information for a variety of applications including 3-D target classification, autonomous vehicles, and robot vision. This research is part of an effort to develop a 3-D object recognition system for vehicle objects in air-to-ground laser range imagery. The full system includes image feature extraction, object modeling, model-driven prediction, and feature to model matching. This paper presents several three-dimensional feature extraction techniques for use on laser range imagery. These include object-ground segmentation, projection image generation from range data, and 3-D physical edge detection. We emphasize extracting 3-D physical features of the object from 3-D range data without restricting ourselves in a sensor-centered range image format. The object-ground segmentation and projection image generation techniques extract global object features from range data, and are useful for object orientation estimation and major structures identification. The 3-D physical edge detector directly calculates the physical angle of the object surface. It is not only useful for physical edge (convex, concave, occluding) detection, but also provides useful information for extracting planar and curved surfaces.

  10. SNAKE DEPLORIZING RESONANCE STUDY IN RHIC

    SciTech Connect

    BAI,M.; CAMERON, P.; LUCCIO, A.; HUANG, H.; PITISYN, V.; ET AL.

    2007-06-25

    Snake depolarizing resonances due to the imperfect cancellation of the accumulated perturbations on the spin precession between snakes were observed at the Relativistic Heavy Ion Collider (RHIC). During the RHIC 2005 and 2006 polarized proton runs, we mapped out the spectrum of odd order snake resonance at Q{sub y} = 7/10. Here, Q, is the beam vertical betatron tune. We also studied the beam polarization after crossing the 7/10th resonance as a function of resonance crossing rate. This paper reports the measured resonance spectrum as well as the results of resonance crossing.

  11. Designing triple resonance Tesla transformers of arbitrary modal frequency ratio

    NASA Astrophysics Data System (ADS)

    Reed, John Randolph

    2006-03-01

    The purpose of this article is to disclose an automated method to design and investigate multimegavolt triple resonance Tesla transformers. The pulse transformer's "frequency equation" is presented for the first time. The frequency equation derivation properly models all the inductors, with their self-capacitances, which have yet to be treated in an orthodox manner. The analysis gives new insight into the transformer by showing the relationship between the roots of the frequency equation and the transformer's modal frequencies. The roots are shown to be subject to manipulation, and so the modal frequencies are controllable. The method efficiently extracts solutions (transformer circuits) from the frequency equation constrained to oscillate at an arbitrary and general modal frequency ratio (to include noninteger). A ratio of the present general interest is 1:2:3. This particular ratio forces the maxima of the three coexisting modal oscillations to align, and their amplitudes sum to produce a local maximum, at a specific time. The same alignment phenomenon occurs with the dual resonance transformer with a modal ratio of 1:2. A pulse transformer is designed as a demonstration. The energy in each of the three oscillations is examined at the moment of peak voltage in the demonstration transformer to show the investigative power of the new equations. This generalized tool will prove useful in the campaign to analytically locate global maximums from the triple resonance transformer's governing amplitude equation for output voltage.

  12. Ferromagnetic resonance in compositionally modulated Cu-Ni thin films

    NASA Astrophysics Data System (ADS)

    Dillon, J. F., Jr.; Gyorgy, E. M.; Rupp, L. W., Jr.; Yafet, Y.; Testardi, L. R.

    1981-03-01

    Ferromagnetic resonance at 12 GHz has been studied in some of the same compositionally modulated CuNi films on which magnetization measurements were reported recently. The best samples, e.g., a film designated [20?10]880 (i.e, 880 repetitions of [20Å Cu on 10Å Ni]) show the 295 K resonance behavior expected for a magnetic material with an easy plane uniaxial anisotropy and a line width ?H˜103 Oe. As T is lowered the quantity Drf.?4?M+2K/M extracted from the line position data using Kittel's equations increases roughly linearly with decreasing T. For [10?10] 2440, Drf goes from ˜4 kOe at 295 K to ˜20 kOe at 80 K. This low temperature value agrees with that obtained from He temperature magnetization curves. A remarkable result of the magnetization measurements was the fact that Ddc at 4.2 K was essentially the same for [10?10], [20?10], and [40?10] samples. In striking contrast, the microwave values at 80 K decrease markedly with increasing thickness of the Cu layers. Simple averaging of the resonance equations has not led to an explanation of this difference.

  13. Resonator coiling in thermoacoustic engines

    SciTech Connect

    Olson, J.R.; Swift, G.W. [Condensed Matter and Thermal Phys. Group, Los Alamos Natl. Lab, Los Alamos, NM 87545 (United States)

    1995-11-01

    Coiling the resonator of a thermoacoustic engine is one way to try to minimize the engine`s size. However, flow in bent pipes is known to alter the fluid flow pattern because of centrifugal forces. Theory and measurements will be presented on the energy dissipation caused by oscillating flow in curved pipes. Measurements have been taken using free oscillations of liquids in U-tubes, and using a thermoacoustic engine with straight and bent resonators. [Work supported by the TTI program of the US Department of Energy, and by the Tektronix Corporation.

  14. Gallium nitride nanowire electromechanical resonators

    NASA Astrophysics Data System (ADS)

    Gray, Jason Michael

    Nanoscale mechanical resonators are of great interest for high-resolution sensing applications, where the small resonator mass and high quality factor (Q, defined as resonance frequency f0 over full width at half maximum power) lead to unprecedented sensitivity. Here, we investigate gallium nitride (GaN) nanowire (NW) resonators. The single-crystal, c-axis NWs are 5 mum -- 20 mum long, with diameters from 50 nm -- 500 nm, and grow essentially free of defects. Our initial experiments involve measuring the resonances of as-grown NWs in a scanning electron microscope, where we observe exceptionally high Q values of 10 4 -- 105, one to two orders of magnitude higher than most NWs of comparable size. Using a single NW as a mass sensor, we then demonstrate a sub-attogram mass sensitivity. To provide a more flexible measurement technique that avoids electron-microscope detection, we fabricate doubly clamped NWs with an entirely electronic drive and readout scheme using a combination of lithographic patterning and dielectrophoresis. An electrostatic gate induces vibration, while readout utilizes the piezoresistivity of GaN. Observed resonances range from 9--36 MHz with Q values typically around 103 at room temperature and 10 -4 Pa. We use the behavior of f0 and Q to sense the NW's local environment, such as the additional sources of energy dissipation not present in the as-grown NWs. By cooling the device to 8 K, Q increases by an order of magnitude to above 104, with a highest value to date of 26,000 under vacuum. We explore additional NW properties through the thermal noise in the NW's mechanical motion and the exponential decay of mechanical motion in the presence of burst drive. Finally, we investigate the low-frequency 1/f parameter noise displayed by f0. We show that the noise in f0 is consistent with noise in the NW's resistance leading to temperature noise from local Joule heating, which in turn generates resonance frequency noise. For sensor applications, there will be optimal drive conditions that balance the f 0 noise with the signal-to-noise ratio of the system. With these insights, along with the simple drive and readout technique, these GaN-NW doubly clamped resonators have significant potential for high-resolution sensing applications.

  15. Annular Bragg defect mode resonators

    NASA Astrophysics Data System (ADS)

    Scheuer, Jacob; Yariv, Amnon

    2003-11-01

    We propose and analyze a new type of a resonator in an annular geometry that is based on a single defect surrounded by radial Bragg reflectors on both sides. We show that the conditions for efficient mode confinement are different from those of the conventional Bragg waveguiding in a rectangular geometry. A simple and intuitive approach to the design of optimal radial Bragg reflectors is proposed and employed, yielding chirped gratings. Small bending radii and strong control over the resonator dispersion are possible by the Bragg confinement. A design compromise between large free-spectral-range requirements and fabrication tolerances is suggested.

  16. Interventional Cardiovascular Magnetic Resonance Imaging

    PubMed Central

    Saikus, Christina E.; Lederman, Robert J.

    2010-01-01

    Cardiovascular magnetic resonance (CMR) combines excellent soft-tissue contrast, multiplanar views, and dynamic imaging of cardiac function without ionizing radiation exposure. Interventional cardiovascular magnetic resonance (iCMR) leverages these features to enhance conventional interventional procedures or to enable novel ones. Although still awaiting clinical deployment, this young field has tremendous potential. We survey promising clinical applications for iCMR. Next, we discuss the technologies that allow CMR-guided interventions and, finally, what still needs to be done to bring them to the clinic. PMID:19909937

  17. Resonance impact ionization in superlattices

    NASA Astrophysics Data System (ADS)

    Mon, K. K.; Hess, K.

    1982-06-01

    We propose an enhancement of the electron or hole impact ionization coefficients (? or ?) by introducing resonant impact ionization states into the (conduction or valence) band by using suitable lattice matched multilayer heterojunctions (superlattices). Model calculations for the AlAs:GaAs superlattice indicate resonance enhancements can occur over a wide range of energy gaps (1.54-1.9 eV). The gap can be varied by choosing the appropriate ratio of the alternating layer thickness. This effect should be useful for improving the signal/noise ratio of avalanche photodiodes significantly.

  18. Resonance in a head massager

    NASA Astrophysics Data System (ADS)

    Ribeiro, Jair Lúcio Prados

    2015-04-01

    Mechanical structures such as pendula, bridges, or buildings always exhibit one (or more) natural oscillation frequency.1 If that structure is subjected to oscillatory forces of this same frequency, resonance occurs, with consequent increase of the structure oscillation amplitude. There is no shortage of simple experiments for demonstrating resonance in high school classes using a variety of materials, such as saw blades,2 guitars,3 pendulums,4 wine glasses,5 bottles,6 Ping-Pong balls,7 and pearl strings.8 We present here an experimental demonstration using only an inexpensive head (or scalp) massager, which can be purchased for less than a dollar.

  19. MATERIALS AND METHODS 1) DNA extraction

    E-print Network

    Collins, Gary S.

    MATERIALS AND METHODS 1) DNA extraction · DNA was extracted from the ileo-cecal nodes of 475 Holstein cows from two herds using the Qiagen DNA extraction kit (Valencia, CA). 2) Map detection · Map and Jerome, Idaho, respectively. DNA was extracted from ileo-cecal lymph nodes using the Qiagen (Valencia, CA

  20. Stochastic resonance in electrical circuits. I. Conventional stochastic resonance

    Microsoft Academic Search

    Dmitrii G. Luchinsky; Riccardo Mannella; Peter V. E. McClintock; Nigel G. Stocks

    1999-01-01

    Stochastic resonance (SR), a phenomenon in which a periodic signal in a nonlinear system can be amplified by added noise, is introduced and discussed. Techniques for investigating SR using electronic circuits are described in practical terms. The physical nature of SR, and the explanation of weak-noise SR as a linear response phenomenon, are considered. Conventional SR, for systems characterized by