Sample records for resonant third-integer extraction

  1. Preliminaries toward studying resonant extraction from the Debuncher

    SciTech Connect

    Michelotti, Leo; Johnstone, John; /Fermilab

    2009-06-01

    A recent proposal to detect {mu} {yields} e direct conversion at Fermilab asks for slow extraction of protons from the antiproton source, specifically from the Debuncher. [1] A third-integer resonance originally was considered for this, partly because of the Debuncher's three-fold symmetry and partly because its operational horizontal tune, {nu}{sub x} {approx} 9.765, is already within 0.1 of {nu}{sub x} = 29/3. Using a half integer resonance, {nu}{sub x} = 19/2, though not part of the original proposal, has been suggested more recently because (a) Fermilab has had a good deal of experience with half-integer extraction from the Tevatron, the Main Injector and the erstwhile Main Ring, and (b) for reasons we shall examine later, it depopulates the entire bunch without an abort at the end. This memo presents considerations preliminary to studying both possibilities. It is meant only as a starting point for investigations to be carried out in the future. The working constraints and assumptions have oscillated between two extremes: (1) making minimal changes in the antiproton source to minimize cost and (2) building another machine in the same tunnel. In this memo we adopt an attitude aligned more toward the first. The assumed parameters are listed in Table 1. A few are not (easily) subject to change, such as those related to the beam's momentum and revolution frequency and the acceptance of the debuncher. Two resonance exemplars are presented in the next section, with an explanation of the analytic and semi-analytic calculations that can be done for each. Section 3 contains preliminary numerical work that was done to validate the exemplars within the context of extraction from the Debuncher. A final section contains a summary. Following the bibliography, appendices contain (a) a qualitative, conceptual discussion of extraction for the novice, (b) a telegraphic review of the perturbative incantations used to filter the exemplars as principal resonances of quadrupole, sextupole and octupole distributions, (c) a brief discussion of linearly independent control circuits, and (d) two files describing the antiproton source's rings in MAD v.8 format, not readily available elsewhere. All figures are located at the end. We emphasize again, the work reported here barely begins the effort that will be required to design, validate and perform resonant extraction from the Debuncher. Our goal was to compile these preliminary notes in one place for easy future reference, preferably by a young, intelligent, motivated and energetic graduate student.

  2. Space charge effect of the high intensity proton beam during the resonance extraction for the Mu2e experiment at Fermilab

    SciTech Connect

    Park, Chong Shik; Amundson, James; Johnstone, John; Michelotti, Leo; Nagaslaev, Vladimir; Werkema, Steve; /Fermilab

    2011-03-01

    The proposed Mu2e experiment to search for direct {mu} {yields} e conversion at Fermilab plans slow, resonant extraction of a beam with 3 x 10{sup 12} protons from the Debuncher ring. Space charge of this high intensity beam is a critical factor, since it induces significant betatron tune spread and consequently affects resonance extraction processes, such as spill uniformity and beam losses. This study shows the multi-particle simulation results in the early stages of resonance extraction and spill uniformity in the presence of 2D and 3D space charge effects. We have presented the results of the third-integer resonance extraction in early stage for the Mu2e experiment in the presence of space charge effects. In order to track particles and to calculate self-consistent space charge effects, Synergia2 was used, which is capable of parallel computing. The space charge tune shift was computed and was reasonable value compared with the analytical calculation. Locations of the septum and Lambertson were chosen so that particles are kicked and extracted efficiently. The spill rates for with and without space charge effects were uniform, but should be improved for the early stage after the sextupole field ramping.

  3. 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

  4. 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.

  5. 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.

  6. Automated Brain Extraction from T2-weighted Magnetic Resonance Images

    PubMed Central

    Datta, Sushmita; Narayana, Ponnada A.

    2011-01-01

    Purpose To develop and implement an automated and robust technique to extract brain from T2-weighted images. Materials and Methods Magnetic resonance imaging (MRI) was performed on 75 adult volunteers to acquire dual fast spin echo (FSE) images with fat-saturation technique on a 3T Philips scanner. Histogram-derived thresholds were derived directly from the original images followed by the application of regional labeling, regional connectivity, and mathematical morphological operations to extract brain from axial late-echo FSE (T2-weighted) images. The proposed technique was evaluated subjectively by an expert and quantitatively using Bland-Altman plot and Jaccard and Dice similarity measures. Results Excellent agreement between the extracted brain volumes with the proposed technique and manual stripping by an expert was observed based on Bland-Altman plot and also as assessed by high similarity indices (Jaccard: 0.9825± 0.0045; Dice: 0.9912 ±0.0023). Conclusion Brain extraction using proposed automated methodology is robust and the results are reproducible. PMID:21448946

  7. Selective resonant extraction from the Fermilab Main Injector using electron lens

    SciTech Connect

    Vladimir Shiltsev and John Marriner

    2001-07-20

    We propose to use an electron lens for slow extraction of proton bunches from the Fermilab Main Injector. Negatively charged electron beam colliding with protons causes positive tune shift proportional to the electron current. If the resulting tune satisfies resonance condition, protons move to larger betatron amplitudes as in conventional slow extraction systems. Time variation of the electron current allows slow extraction from particular batches or even slow extraction from a single bunch.

  8. 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.

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

    NASA Astrophysics Data System (ADS)

    Schachter, L.; Dobrescu, S.; Stiebing, K. E.

    2006-03-01

    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 14GHz 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.

  10. Model extraction from magnetic resonance volume data using the deformable pyramid

    Microsoft Academic Search

    Jyrki Lötjönen; Pierre-Jean Reissman; Isabelle E. Magnin; Toivo Katila

    1999-01-01

    A general framework for automatic model extraction from magnetic resonance (MR) images is described. The framework is based on a two-stage algorithm. In the first stage, a geometrical and topological multiresolution prior model is constructed. It is based on a pyramid of graphs. In the second stage, a matching algorithm is described. This algorithm is used to deform the prior

  11. 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.

  12. Analysis of the optical extraction efficiency in gas-flow lasers with different types of resonator

    SciTech Connect

    Barmashenko, B.D.; Rosenwaks, S. [Department of Physics, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel)

    1996-12-01

    The celebrated Rigrod model [J. Appl. Phys. {bold 34,} 2602 (1963)] has recently been shown to be inadequate for calculating the output power of gas-flow lasers when the quenching of excited species is slow and the optical extraction efficiency is high [Opt. Lett. {bold 20,} 1480 (1995)]. The previous analysis of two-level systems is presented here in detail and extended to include the chemical oxygen-iodine laser (COIL). For both two-level systems and COIL{close_quote}s, we obtained simple analytic formulas for the output power, which should be used instead of the Rigrod model. We present the formulas for Fabry{endash}Perot, stable, and unstable resonators. Both the saturation parameter and the extraction efficiency differ from those appearing in the Rigrod model. The highest extraction efficiency is achievable for both stable and unstable resonators with uniform intensity distribution over the resonator cross section and is greater than that calculated by the Rigrod model. A rather surprising conclusion is that the extraction efficiency of unstable resonators can be increased substantially if one increases the length of the part of the mirrors lying downstream of the optical axis. The derived formulas are applied to describe published experimental results of supersonic COIL{close_quote}s. The dependence of the power on the threshold gain is evaluated and from this the plenum yield of singlet oxygen is estimated. The value of the yield is in better agreement with experimental measurements than that obtained by the Rigrod model. {copyright} {ital 1996 Optical Society of America.}

  13. Detection of free radicals in aqueous extracts of cigarette tar by electron spin resonance

    Microsoft Academic Search

    Lun-Yi Zang; Koni Stone; William A. Pryor

    1995-01-01

    Aqueous extracts of cigarette tar (ACT) autooxidize to produce semiquinone, hydroxyl, and superoxide radicals in air-saturated buffered aqueous solutions. The semiquinone species were detected by direct electron spin resonance (ESR) measurements and identified as o-and p-benzosemiquinone radicals by comparison with the ESR signals of catechol and hydroquinone radicals under similar conditions. The rate of formation of these radicals was dependent

  14. Extraction of the target isotope on the collector by the ion cyclotron resonance method

    NASA Astrophysics Data System (ADS)

    Potanin, E. P.

    2008-04-01

    Theoretical issues concerning isotope separation by the ion cyclotron resonance method are considered. A version of the experimental ion cyclotron resonance setup and ways of producing a plasma stream are described. Techniques used to vaporize the working agent and its transport to the ioniation zone are discussed. The separating characteristics of the hot-particle collector at certain parameters of the setup and plasma are calculated. A gadolinium isotope mixture is used as a model. The dependence of the 157Gd target isotope concentration on the separating plate on the longitudinal coordinate reckoned from the front edge of the separator is analyzed for different frequency offsets. The target isotope extraction ratio versus the plate distance of the separator for different values of the offset from the resonance frequency is found.

  15. RNA degradation in cell extracts: real-time monitoring by fluorescence resonance energy transfer.

    PubMed

    Uhler, Sarah A; Cai, Dawen; Man, Yunfang; Figge, Carina; Walter, Nils G

    2003-11-26

    Short noncoding RNAs are increasingly recognized as key regulators of essential cellular processes such as RNA interference. A better understanding of the processes by which such RNAs are degraded is necessary to expand our knowledge of these processes and our ability to harness them. To this end we have developed a novel fluorescence resonance energy transfer (FRET) assay to monitor in real-time the degradation kinetics of short RNAs by a purified RNase and S100 cytosolic HeLa cell extract. An unstructured RNA is found to be degraded more rapidly than a stem-loop RNA under all conditions tested except for low concentrations of cell extract, showing that secondary structure confers protection against RNase activity. The assay also allows for the quantitative comparison of inhibitors such as Contrad70 and aurin tricarboxylic acid (ATA). Finally, gel electrophoretic FRET analysis confirms that HeLa cell extract is dominated by 5' to 3' exonucleolytic activity. PMID:14624543

  16. Light extraction for a doubly resonant cavity organic LED: the RC2LED

    NASA Astrophysics Data System (ADS)

    Vandersteegen, Peter; Mladenovski, Saso; van Elsbergen, Volker; Gartner, Georg; Bienstman, Peter; Neyts, Kristiaan; Baets, Roel

    2007-09-01

    The RC2LED is a substrate emitting OLED which has three additional interference layers between the ITO electrode and the glass substrate. This creates two resonant optical cavities. The RC2LED has 2 resonant optical cavities. The first cavity is also present in regular devices and is formed by metal/organic layers/ITO. The second cavity is formed by 3 additional layers: a high refractive index layer (Nb IIO 5), a low refractive index layer (SiO II) and a high refractive index layer (Nb IIO 5). The additional layers introduce a strong wavelength dependent improvement of the extraction efficiency compared to the OLED without the additional layers. Our simulations show an improvement of the extraction efficiency of over 70% over a wavelength range of 75 nm compared to an OLED without the 3 layers. Light extraction is worse compared to the reference OLED for wavelengths outside this wavelength range. the when compared to the OLED. This improvement has been experimentally verified for a green OLED with an emission between 500nm and 650 nm. A numerical study shows a relative improvement of 10% for the luminous power efficiency of a 3 color white OLED with the additional layers. The emitted white corresponds with the light emitted by illuminant A. The WOLED has been composed of a fluorescent blue emitter, green and red phosphorescent emitters.

  17. 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.

  18. 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

  19. Extracting information about the rotator cuff from magnetic resonance images using deterministic and random techniques.

    PubMed

    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

  20. 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.

  1. Far-field Fano resonance in nanoring lattices modeled from extracted, point dipole polarizability

    SciTech Connect

    DeJarnette, Drew; Forcherio, Gregory T. [Microelectronics and Photonics Graduate Program, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Blake, Phillip [Department of Chemical Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Keith Roper, D., E-mail: dkroper@uark.edu [Microelectronics and Photonics Graduate Program, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Department of Chemical Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States)

    2014-01-14

    Coupling and extinction of light among particles representable as point dipoles can be characterized using the coupled dipole approximation (CDA). The analytic form for dipole polarizability of spheroidal particles supports rapid electrodynamic analysis of nanoparticle lattices using CDA. However, computational expense increases for complex shapes with non-analytical polarizabilities which require discrete dipole (DDA) or higher order approximations. This work shows fast CDA analysis of assembled nanorings is possible using a single dipole nanoring polarizability extrapolated from a DDA calculation by summing contributions from individual polarizable volume elements. Plasmon resonance wavelengths of nanorings obtained using extracted polarizabilities blueshift as wall dimensions-to-inner radius aspect ratio increases, consistent with published theory and experiment. Calculated far-field Fano resonance energy maximum and minimum wavelengths were within 1% of full volume element results. Considering polarizability allows a more complete physical picture of predicting plasmon resonance location than metal dielectric alone. This method reduces time required for calculation of diffractive coupling more than 40?000-fold in ordered nanoring systems for 400–1400?nm incident wavelengths. Extension of this technique beyond nanorings is possible for more complex shapes that exhibit dipolar or quadrupole radiation patterns.

  2. Third Interger Resonance Slow Extraction Using RFKO at High Space Charge

    SciTech Connect

    Nagaslaev, V.; Amundson, J.; Johnstone, J.; Park, C.S.; Werkema, S.; /Fermilab

    2011-09-15

    A proposal to search for direct {mu} {yields} e conversion at Fermilab requires slow, resonant extraction of an intense proton beam. Large space charge forces will present challenges, partly due to the substantial betatron tune spread. The main challenges will be maintaining a uniform spill profile and moderate losses at the septum. We propose to use 'radio frequency knockout' (RFKO) for fine tuning the extraction. Strategies for the use of the RFKO method will be discussed here in the context of the Mu2e experiment. The feasibility of this method has been demonstrated in simulations. Tracking simulations show that optimal RFKO frequency modulation in case of the SC beam tune spread is substantially different from that of chromatic tune spread. FM should be centred at the bare betatron frequency rather than in the middle of the tune spread, and additional chromaticity must be added in order to facilitate rapid dilution of the dipole oscillations. Heating efficiency slowly decreases with the SC growing. Colored noise modulation (random signal within a given bandwidth) appears to be the most effective way of modulation, however its advantage over linear modulation is not very large, so practical reasons may prevail in the final choice between the two.

  3. 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.

  4. 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.

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

    NASA Astrophysics Data System (ADS)

    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.

  6. 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.

  7. Electron spin resonance study of free radicals formed from a procyanidin-rich pine ( Pinus maritima) bark extract, pycnogenol

    Microsoft Academic Search

    Qiong Guo; Baolu Zhao; Lester Packer

    1999-01-01

    The free radical generated from the oxidation of a French maritima pine bark extract Pycnogenol (PYC), by the horseradish peroxidase (HRP)–hydrogen peroxide (H2O2) system at pH 7.4–10.0 was studied using electron spin resonance (ESR) spectrometer. The formation rate of the PYC radical (aH = 0.92G; g = 2.0055) was dependent on the PYC and HRP concentrations and pH; the lifetime

  8. Seasonal variations of global lightning activity extracted from Schumann resonances using a genetic algorithm method

    Microsoft Academic Search

    Heng Yang; Victor P. Pasko; Gabriella Sátori

    2009-01-01

    A three-dimensional Finite Difference Time Domain (FDTD) model of the Earth-ionosphere cavity with a realistic conductivity profile is employed to study the global lightning activity using the observed intensity variations of Schumann resonances (SR). Comparison of the results derived from our FDTD model and the previous studies by other authors on related subjects shows that Schumann resonance is a good

  9. 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).

  10. Conceptual design of first toroidal electron cyclotron resonance ion source and modeling of ion extraction from it

    E-print Network

    Caliri, C; Volpe, F A

    2015-01-01

    Electron Cyclotron Resonance Ion Sources (ECRIS) progressed to higher and higher ion currents and charge states by adopting stronger magnetic fields (beneficial for confinement) and proportionally higher ECR frequencies. Further improvements would require the attainment of "triple products" of density, temperature and confinement time comparable with major fusion experiments. For this, we propose a new, toroidal rather than linear, ECRIS geometry, which would at the same time improve confinement and make better use of the magnetic field. Ion extraction is more complicated than from a linear device, but feasible, as our modelling suggests: single-particle tracings showed successful extraction by at least two techniques, making use respectively of a magnetic extractor and of ExB drifts. Additional techniques are briefly discussed.

  11. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

    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.

  13. Carbon beam extraction with 14.5 GHz electron cyclotron resonance ion source at Korea Atomic Energy Research Institute

    NASA Astrophysics Data System (ADS)

    Lee, Cheol Ho; Oh, Byung-Hoon; Chang, Dae-Sik; Jeong, Sun-Chan

    2014-02-01

    A 14.5 GHz Electron Cyclotron Resonance ion source (ECRIS) has been made to produce C4+ beam for using a carbon therapy facility and recently tested at KAERI. Highly charged carbon ions have been successfully extracted. When using only CO2 gas, the beam current of C4+ was almost 14 ?A at 15 kV extraction voltage. To get higher current of the C4+ beam, while optimizing confinement magnetic field configuration (e.g., axial strengths at minimum and extraction side), gas-mixing (CO2/He), and biased disk were introduced. When the gas mixing ratio of the CO2/He gas is 1:8 at an operational pressure of 5 × 10-7 mbar and the disk was biased to -150 V relative to the ion source body, the highest current of the C4+ beam was achieved to be 50 ?A, more than three times higher than previously observed only with CO2 gas. Some details on the operating conditions of the ECRIS were discussed.

  14. 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

  15. Resolution of the multichannel anomaly in the extraction of S-matrix resonance-pole parameters

    SciTech Connect

    Ceci, Sasa [Rudjer Boskovic Institute, Bijenicka cesta 54, P.O. Box 180, 10002 Zagreb (Croatia); Department of Physics and Astronomy, University of Georgia, Athens, GA 30602 (United States); Stahov, Jugoslav [Abilene Christian University, ACU Station Box 27963, Abilene, TX 79699 (United States); University of Tuzla, Faculty of Science, Univerzitetska 4, 35000 Tuzla (Bosnia and Herzegowina); Svarc, Alfred; Zauner, Branimir [Rudjer Boskovic Institute, Bijenicka cesta 54, P.O. Box 180, 10002 Zagreb (Croatia); Watson, Shon [Abilene Christian University, ACU Station Box 27963, Abilene, TX 79699 (United States)

    2008-06-01

    Within the framework of a mathematically well-defined coupled-channel T-matrix model we have improved the existing multichannel pole-extraction procedure based on the numerical analytic continuation of the channel propagator, and for the first time we present the full set of pole parameters for already published amplitudes. Standard single-channel pole-extraction method (speed plot) was then applied to those amplitudes and resulting sets of T-matrix poles were inspected. The anomaly has been established that in some partial waves the pole values extracted using the standard single-channel methods differ not only from the values obtained using the analytic continuation method, but also change from one reaction to another. Inspired by this peculiarity, we have developed a new single-channel pole-extraction method based solely on the assumption of the partial wave analyticity. Since the speed plot turns out to be the lowest order term of the proposed method, the anomaly is understood and resolved.

  16. Is it Possible to Extract Brain Metabolic Pathways Information from In Vivo H Nuclear Magnetic Resonance Spectroscopy Data?

    E-print Network

    de Lara, Alejandro Chinea Manrique

    2010-01-01

    In vivo H nuclear magnetic resonance (NMR) spectroscopy is an important tool for performing non-invasive quantitative assessments of brain tumour glucose metabolism. Brain tumours are considered as fast-growth tumours because of their high rate of proliferation. In addition, tumour cells exhibit profound genetic, biochemical and histological differences with respect to the original non-transformed cellular types. Therefore, there is a strong interest from the clinical investigator point of view in understanding the role of brain metabolites in normal and pathological conditions and especially on the development of early tumour detection techniques. Unfortunately, current diagnosis techniques ignore the dynamic aspects of these signals. It is largely believed that temporal variations of NMR Spectra are noisy or just simply do not carry enough information to be exploited by any reliable diagnosis procedure. Thus, current diagnosis procedures are mainly based on empirical observations extracted from single avera...

  17. Studies of emittance of multiply charged ions extracted from high temperature superconducting electron cyclotron resonance ion source, PKDELIS

    SciTech Connect

    Rodrigues, G.; Lakshmy, P. S.; Kumar, Sarvesh; Mandal, A.; Kanjilal, D.; Roy, A. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Baskaran, R. [Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamilnadu 603102 (India)

    2010-02-15

    For the high current injector project at Inter University Accelerator Centre, a high temperature superconducting electron cyclotron resonance (ECR) ion source, PKDELIS, would provide the high charge state ions. The emittance of the ECR ion source is an important parameter to design further beam transport system and to match the acceptances of the downstream radio frequency quadrupole and drift tube linac accelerators of the high current injector. The emittance of the analyzed beam of PKDELIS ECR source has been measured utilizing the three beam size technique. A slit and two beam profile monitors positioned at fixed distances from each other were used to measure the beam size. The digitized beam profiles have been analyzed to determine the emittance of various multiply charged ions. The variation of emittance with gas mixing, ultrahigh frequency power, and extraction energy are discussed in this presentation.

  18. 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.

  19. 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.

  20. Extraction of Resonance Parameters and Role of the Final State Interactions

    NASA Astrophysics Data System (ADS)

    Strakovsky, Igor I.; Briscoe, William J.; Kudryavtsev, Alexander E.; Tarasov, Vladimir E.

    2014-01-01

    We present an overview of the SAID group effort to analyze new ?n ? ?-p cross sections vs. the world database to get new multipoles and determine neutron electromagnetic couplings. The differential cross section for the processes ?n ? ?-p was extracted from new measurements at CLAS and MAMI-B accounting for Fermi motion effects in the impulse approximation (IA) as well as NN- and ?N-FSI effects beyond the IA. We evaluated results of several pion photoproduction analyses and compared ?N PWA results as a constraint for analyses of pion photoproduction data (Watson's theorem).

  1. Microwave-energy extraction from a resonator via oversized interference switch

    NASA Astrophysics Data System (ADS)

    Avgustinovich, V. A.; Artemenko, S. N.; Zhukov, A. A.

    2013-05-01

    We have studied an interference switch based on an oversized H-plane rectangular waveguide T-junction. Conditions necessary for effective operation of the switch as an energy extractor are evaluated. Microwave pulses of 3.5-ns duration with 2.8-MW power at a gain of 17.5 dB have been obtained using a prototype microwave compressor for the 3-cm waveband with a 72 × 34 mm2 waveguide resonator and a 58 × 25 mm2 waveguide switch. It is shown that, using the proposed switch, it is possible to obtain RF pulses with a power of up to ˜0.1 GW in the 3-cm band and ˜1 GW in the 10-cm band.

  2. Metabonomic analysis of water extracts from different angelica roots by ¹H-nuclear magnetic resonance spectroscopy.

    PubMed

    Chan, Pui Hei; Zhang, Wendy L; Lau, Chung-Ho; Cheung, Chi Yuen; Keun, Hector C; Tsim, Karl W K; Lam, Henry

    2014-01-01

    Angelica Radix, the roots of the genus Angelica, has been used for more than 2,000 years as a traditional medicine in Eastern Asia. The Chinese Pharmacopoeia records more than 100 herbal formulae containing Angelica roots. There are two common sources of Angelica roots, Angelica sinensis from China and A. gigas from Korea. The two species of Angelica roots differ in their chemical compositions, pharmacological properties and clinical efficacy. ¹H-NMR metabolic profiling has recently emerged as a promising quality control method for food and herbal chemistry. We explored the use of ¹H-NMR metabolic profiling for the quality control of Angelica Radix. Unlike previous work, we performed the metabolic profiling on hot water extracts, so as to mimic the clinically relevant preparation method. Unsupervised principle component analyses of both the full spectral profile and a selection of targeted molecules revealed a clear differentiation of three types of Angelica roots. In addition, the levels of 13 common metabolites were measured. Statistically significant differences in the levels of glucose, fructose and threonine were found between different sources of Angelica. Ferulic acid, a marker commonly used to evaluate Angelica root, was detected in our samples, but the difference in ferulic acid levels between the samples was not statistically significant. Overall, we successfully applied ¹H-NMR metabolic profiling with water extraction to discriminate all three sources of Angelica roots, and obtained quantitative information of many common metabolites. PMID:24658570

  3. Bioconjugated persistent luminescence nanoparticles for Föster resonance energy transfer immunoassay of prostate specific antigen in serum and cell extracts without in situ excitation.

    PubMed

    Wu, Bo-Yue; Yan, Xiu-Ping

    2015-02-17

    A novel Föster resonance energy transfer (FRET) immunoassay based on persistent luminescence nanoparticles (PLNP) was established for prostate specific antigen (PSA) detection in serum and cell extracts without in situ excitation. The specific FRET behavior allows highly selective and sensitive ratiometric photoluminescent detection of PSA in biological samples. PMID:25656741

  4. Nuclear resonant inelastic x-ray scattering: Methodology and extraction of vibrational properties of minerals

    NASA Astrophysics Data System (ADS)

    Hu, M. Y.; Alp, E. E.; Bi, W.; Sturhahn, W.; Toellner, T. S.; Zhao, J.

    2013-12-01

    Nuclear resonant inelastic x-ray scattering (NRIXS) is a synchrotron radiation based experimental method [1]. Since its introduction almost 20 years ago [2], NRIXS has found an expanding range of applications of studying lattice dynamics in condensed matter physics, materials science, high-pressure research, geosciences, and biophysics. After the first high pressure application in geophysics of measuring sound velocity of iron up to 153 GPa [3], it has become a widely used method to investigate deep earth compositions through sound velocity measurements [4,5]. Thermodynamic properties are also explored, in particular Grueneisen parameters [6]. Later, it was realized that isotope fractionaton factors can be derived from NRIXS measurements [7,8]. Sum rules and moments of NRIXS is a critical part of this methodology [9,10]. We will discuss this and in general the data analysis of NRIXS which enables the above mentioned applications. [1] Alp et al. Hyperfine Interactions 144/145, 3 (2002) [2] Sturhahn et al., PRL 74, 3832 (1995) [3] Mao et al., Science 292, 914 (2001) [4] Hu et al., PRB 67, 094304 (2003) [5] Sturhahn & Jackson, GSA special paper 421 (2007) [6] Murphy et al., Geophys. Res. Lett. 38, L24306 (2011) [7] Polyakov, Science 323, 912 (2009) [8] Dauphas et al., Geochimica et Cosmochimica Acta 94, 254 (2012) [9] Lipkin, PRB 52, 10073 (1995) [10] Hu et al., PRB 87, 064301 (2013)

  5. Pattern Recognition Analysis of Proton Nuclear Magnetic Resonance Spectra of Brain Tissue Extracts from Rats Anesthetized with Propofol or Isoflurane

    PubMed Central

    Kawaguchi, Hiroshi; Hirakawa, Keiko; Miyauchi, Kensuke; Koike, Kaoru; Ohno, Youkichi; Sakamoto, Atsuhiro

    2010-01-01

    Background General anesthesia is routinely used as a surgical procedure and its safety has been endorsed by clinical outcomes; however, its effects at the molecular level have not been elucidated. General anesthetics influence glucose metabolism in the brain. However, the effects of anesthetics on brain metabolites other than those related to glucose have not been well characterized. We used a pattern recognition analysis of proton nuclear magnetic resonance spectra to visualize the changes in holistic brain metabolic phenotypes in response to the widely used intravenous anesthetic propofol and the volatile anesthetic isoflurane. Methodology/Principal Findings Rats were randomized into five groups (n?=?7 each group). Propofol and isoflurane were administered to two groups each, for 2 or 6 h. The control group received no anesthesia. Brains were removed directly after anesthesia. Hydrophilic compounds were extracted from excised whole brains and measured by proton nuclear magnetic resonance spectroscopy. All spectral data were processed and analyzed by principal component analysis for comparison of the metabolite profiles. Data were visualized by plotting principal component (PC) scores. In the plots, each point represents an individual sample. The propofol and isoflurane groups were clustered separately on the plots, and this separation was especially pronounced when comparing the 6-h groups. The PC scores of the propofol group were clearly distinct from those of the control group, particularly in the 6-h group, whereas the difference in PC scores was more subtle in the isoflurane group and control groups. Conclusions/Significance The results of the present study showed that propofol and isoflurane exerted differential effects on holistic brain metabolism under anesthesia. PMID:20567596

  6. 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.

  7. Preliminary results of the ion extraction simulations applied to the MONO1000 and SUPERSHyPIE electron cyclotron resonance ion sources

    SciTech Connect

    Pierret, C.; Maunoury, L.; Biri, S.; Pacquet, J. Y.; Tuske, O.; Delferriere, O. [CIRIL, avenue Henri Becquerel, BP 5133, F-14070 Caen cedex 05 (France); ATOMKI, Bem ter 18/c, H-4026 Debrecen (Hungary); GANIL, Bd H. Becquerel BP 55027, F-14076 Caen cedex 05 (France); CEA/Saclay, DSM/DAPNIA, 91191 Gif/Yvette (France)

    2008-02-15

    The goal of this article is to present simulations on the extraction from an electron cyclotron resonance ion source (ECRIS). The aim of this work is to find out an extraction system, which allows one to reduce the emittances and to increase the current of the extracted ion beam at the focal point of the analyzing dipole. But first, we should locate the correct software which is able to reproduce the specific physics of an ion beam. To perform the simulations, the following softwares have been tested: SIMION 3D, AXCEL, CPO 3D, and especially, for the magnetic field calculation, MATHEMATICA coupled with the RADIA module. Emittance calculations have been done with two types of ECRIS: one with a hexapole and one without a hexapole, and the difference will be discussed.

  8. 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

    NASA Astrophysics Data System (ADS)

    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.

  9. 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

    SciTech Connect

    Yorita, T., E-mail: yorita@rcnp.osaka-u.ac.jp; Hatanaka, K.; Fukuda, M.; Ueda, H.; Yasuda, Y.; Morinobu, S.; Tamii, A.; Kamakura, K. [Research Center for Nuclear Physics (RCNP), Osaka University, Osaka 567-0047 (Japan)] [Research Center for Nuclear Physics (RCNP), Osaka University, Osaka 567-0047 (Japan)

    2014-02-15

    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.

  10. 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

  11. 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

  12. 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

  13. Extracting partial decay rates of helium from complex rotation: autoionizing resonances of the one-dimensional configurations

    NASA Astrophysics Data System (ADS)

    Zimmermann, Klaus; Lugan, Pierre; Jörder, Felix; Heitz, Nicolai; Schmidt, Maximilian; Bouri, Celsus; Rodriguez, Alberto; Buchleitner, Andreas

    2015-01-01

    Partial autoionization rates of doubly excited one-dimensional helium in the collinear Zee and eZe configuration are obtained by means of the complex rotation method. The approach presented here relies on a projection of back-rotated resonance wave functions onto singly ionized H{{e}+} channel wave functions and the computation of the corresponding particle fluxes. In spite of the long-range nature of the Coulomb potential between the electrons and the nucleus, an asymptotic region where the fluxes are stationary is clearly observed. Low-lying doubly excited states are found to decay predomintantly into the nearest single-ionization continuum. This approach paves the way for a systematic analysis of the decay rates observed in higher-dimensional models, and of the role of electronic correlations and atomic structure in recent photoionization experiments.

  14. 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

  15. 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

  16. Targeting high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance analysis with high-resolution radical scavenging profiles-Bioactive secondary metabolites from the endophytic fungus Penicillium namyslowskii.

    PubMed

    Wubshet, Sileshi G; Nyberg, Nils T; Tejesvi, Mysore V; Pirttilä, Anna Maria; Kajula, Marena; Mattila, Sampo; Staerk, Dan

    2013-08-01

    The high-resolution radical scavenging profile of an extract of the endophytic fungus Penicillium namyslowskii was used to target analysis by high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy, i.e., HPLC-HRMS-SPE-NMR, for identification of anti-oxidative secondary metabolites. This revealed the two chromatographic peaks with the highest relative response in the radical scavenging profile to be griseophenone C and peniprequinolone. The HPLC-HRMS-SPE-NMR analysis was performed in the tube-transfer mode using a cryogenically cooled NMR probe designed for 1.7mm NMR tubes. To further explore the potential of the above HPLC-HRMS-SPE-NMR platform for analysis of endophytic extracts, six peaks displaying no radical scavenging activity were also analyzed. This allowed unambiguous identification of six metabolites, i.e., dechlorogriseofulvin, dechlorodehydrogriseofulvin, griseofulvin, dehydrogriseofulvin, mevastatin acid, and mevastatin. The high mass sensitivity of the 1.7mm cryogenically cooled NMR probe allowed for the first time acquisition of direct detected (13)C NMR spectra of fungal metabolites, i.e., dechlorogriseofulvin and griseofulvin, directly from crude extract via HPLC-HRMS-SPE-NMR. Dechlorodehydrogriseofulvin was reported for the first time from nature. PMID:23827469

  17. 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

  18. Identification of degradation products in loxoprofen sodium adhesive tapes by liquid chromatography–mass spectrometry and dynamic pressurized liquid extraction–solid-phase extraction coupled to liquid chromatography–nuclear magnetic resonance spectroscopy

    Microsoft Academic Search

    Tomonori Murakami; Takao Kawasaki; Akira Takemura; Naoto Fukutsu; Naoyuki Kishi; Fumiyo Kusu

    2008-01-01

    Rapid and unambiguous identification of three degradation products (DP-1, DP-2 and DP-3) found in heat-stressed loxoprofen sodium adhesive tapes (Loxonin tapes) was achieved by LC–MS and dynamic pressurized liquid extraction (PLE)–solid-phase extraction (SPE) coupled to LC–NMR without complicated isolation or purification processes. The molecular formulae of the degradation products were determined by accurate mass measurements and product ion analyses and

  19. A study on prevention of an electric discharge at an extraction electrode of an electron cyclotron resonance ion source for cancer therapy

    SciTech Connect

    Kishii, Y., E-mail: Ando.Yasuto@ct.MitsubishiElectric.co.jp; Kawasaki, S. [Energy Systems Center, Mitsubishi Electric Corporation, 1-1-2 Wadasaki-cho, Hyogo-ku, Kobe 652-8555 (Japan)] [Energy Systems Center, Mitsubishi Electric Corporation, 1-1-2 Wadasaki-cho, Hyogo-ku, Kobe 652-8555 (Japan); Kitagawa, A.; Muramatsu, M. [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)] [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Uchida, T. [Bio-Nano Electronics Research Center, Toyo University, 2100 Kujirai, Kawagoe 350-8585 (Japan) [Bio-Nano Electronics Research Center, Toyo University, 2100 Kujirai, Kawagoe 350-8585 (Japan); Graduate School of Interdisciplinary New Science, Toyo University, 2100 Kujirai, Kawagoe 350-8585 (Japan)

    2014-02-15

    A compact ECR ion source has utilized for carbon radiotherapy. In order to increase beam intensity with higher electric field at the extraction electrode and be better ion supply stability for long periods, electric geometry and surface conditions of an extraction electrode have been studied. Focusing attention on black deposited substances on the extraction electrode, which were observed around the extraction electrode after long-term use, the relation between black deposited substances and the electrical insulation property is investigated. The black deposited substances were inspected for the thickness of deposit, surface roughness, structural arrangement examined using Raman spectroscopy, and characteristics of electric discharge in a test bench, which was set up to simulate the ECR ion source.

  20. A study on prevention of an electric discharge at an extraction electrode of an electron cyclotron resonance ion source for cancer therapy

    NASA Astrophysics Data System (ADS)

    Kishii, Y.; Kawasaki, S.; Kitagawa, A.; Muramatsu, M.; Uchida, T.

    2014-02-01

    A compact ECR ion source has utilized for carbon radiotherapy. In order to increase beam intensity with higher electric field at the extraction electrode and be better ion supply stability for long periods, electric geometry and surface conditions of an extraction electrode have been studied. Focusing attention on black deposited substances on the extraction electrode, which were observed around the extraction electrode after long-term use, the relation between black deposited substances and the electrical insulation property is investigated. The black deposited substances were inspected for the thickness of deposit, surface roughness, structural arrangement examined using Raman spectroscopy, and characteristics of electric discharge in a test bench, which was set up to simulate the ECR ion source.

  1. Metabolomic analysis of Strychnos nux-vomica, Strychnos icaja and Strychnos ignatii extracts by 1H nuclear magnetic resonance spectrometry and multivariate analysis techniques

    Microsoft Academic Search

    Michel Frédérich; Young Hae Choi; Luc Angenot; Goetz Harnischfeger; Alfons W. M. Lefeber; Robert Verpoorte

    2004-01-01

    1H Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos nux-vomica (seeds, stem bark, root bark), Strychnos ignatii (seeds), and Strychnos icaja (leaves, stem bark, root bark, collar bark). The principal component analysis (PCA) of the 1H NMR spectra showed a clear discrimination between all samples, using the three first

  2. Resonances and resonance widths

    SciTech Connect

    Collins, T.

    1986-05-01

    Two-dimensional betatron resonances are much more important than their simple one-dimensional counterparts and exhibit a strong dependence on the betatron phase advance per cell. A practical definition of ''width'' is expanded upon in order to display these relations in tables. A primarily pedagogical introduction is given to explain the tables, and also to encourage a wider capability for deriving resonance behavior and wider use of ''designer'' resonances.

  3. Benzimidazole carbamate residues in milk: Detection by Surface Plasmon Resonance-biosensor, using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method for extraction.

    PubMed

    Keegan, Jemma; Whelan, Michelle; Danaher, Martin; Crooks, Steven; Sayers, Regina; Anastasio, Aniello; Elliott, Christopher; Brandon, David; Furey, Ambrose; O'Kennedy, Richard

    2009-11-10

    A surface plasmon resonance (SPR) biosensor screening assay was developed and validated to detect 11 benzimidazole carbamate (BZT) veterinary drug residues in milk. The polyclonal antibody used was raised in sheep against a methyl 5(6)-[(carboxypentyl)-thio]-2-benzimidazole carbamate protein conjugate. A sample preparation procedure was developed using a modified QuEChERS method. BZT residues were extracted from milk using liquid extraction/partition with a dispersive solid phase extraction clean-up step. The assay was validated in accordance with the performance criteria described in 2002/657/EC. The limit of detection of the assay was calculated from the analysis of 20 known negative milk samples to be 2.7mugkg(-1). The detection capability (CCbeta) of the assay was determined to be 5mugkg(-1) for 11 benzimidazole residues and the mean recovery of analytes was in the range 81-116%. A comparison was made between the SPR-biosensor and UPLC-MS/MS analyses of milk samples (n=26) taken from cows treated different benzimidazole products, demonstrating the SPR-biosensor assay to be fit for purpose. PMID:19854341

  4. 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.

  5. HPLC-NMR revisited: using time-slice high-performance liquid chromatography-solid-phase extraction-nuclear magnetic resonance with database-assisted dereplication.

    PubMed

    Johansen, Kenneth T; Wubshet, Sileshi G; Nyberg, Nils T

    2013-03-19

    Time-based trapping of chromatographically separated compounds onto solid-phase extraction (SPE) cartridges and subsequent elution to NMR tubes was done to emulate the function of HPLC-NMR for dereplication purposes. Sufficient mass sensitivity was obtained by use of a state-of-the-art HPLC-SPE-NMR system with a cryogenically cooled probe head, designed for 1.7 mm NMR tubes. The resulting (1)H NMR spectra (600 MHz) were evaluated against a database of previously acquired and prepared spectra. The in-house-developed matching algorithm, based on partitioning of the spectra and allowing for changes in the chemical shifts, is described. Two mixtures of natural products were used to test the approach: an extract of Carthamus oxyacantha (wild safflower), containing an array of spiro compounds, and an extract of the endophytic fungus Penicillum namyslowski, containing griseofulvin and analogues. The database matching of the resulting spectra positively identified expected compounds, while the number of false positives was few and easily recognized. PMID:23432092

  6. Coal liquefaction process streams characterization and evaluation. Characterization of coal-derived materials by field desorption mass spectrometry, two-dimensional nuclear magnetic resonance, supercritical fluid extraction, and supercritical fluid chromatography/mass spectrometry

    SciTech Connect

    Campbell, J.A.; Linehan, J.C.; Robins, W.H. [Battelle Pacific Northwest Lab., Richland, WA (United States)

    1992-07-01

    Under contract from the DOE , and in association with CONSOL Inc., Battelle, Pacific Northwest Laboratory (PNL) evaluated four principal and several complementary techniques for the analysis of non-distillable direct coal liquefaction materials in support of process development. Field desorption mass spectrometry (FDMS) and nuclear magnetic resonance (NMR) spectroscopic methods were examined for potential usefulness as techniques to elucidate the chemical structure of residual (nondistillable) direct coal liquefaction derived materials. Supercritical fluid extraction (SFE) and supercritical fluid chromatography/mass spectrometry (SFC/MS) were evaluated for effectiveness in compound-class separation and identification of residual materials. Liquid chromatography (including microcolumn) separation techniques, gas chromatography/mass spectrometry (GC/MS), mass spectrometry/mass spectrometry (MS/MS), and GC/Fourier transform infrared (FTIR) spectroscopy methods were applied to supercritical fluid extracts. The full report authored by the PNL researchers is presented here. The following assessment briefly highlights the major findings of the project, and evaluates the potential of the methods for application to coal liquefaction materials. These results will be incorporated by CONSOL into a general overview of the application of novel analytical techniques to coal-derived materials at the conclusion of CONSOL`s contract.

  7. Application of high performance liquid chromatography coupled to on-line solid-phase extraction-nuclear magnetic resonance spectroscopy for the analysis of degradation products of V-class nerve agents and nitrogen mustard.

    PubMed

    Mazumder, Avik; Kumar, Ajeet; Purohit, Ajay K; Dubey, Devendra K

    2010-04-23

    The detection and identification of the degradation products of nitrogen mustard and nerve agent VX by high performance liquid chromatography coupled to on-line solid-phase extraction-nuclear magnetic resonance spectroscopy (HPLC-UV-SPE-NMR) were demonstrated. The analytes selected for the study were N,N-dimethylaminoethanol (DMAE), N,N-diethylaminoethanol (DEAE), N,N-diisopropylaminoethanol (DIAE) and triethanolamine (TEA). Offline solid-phase extraction (SPE) followed by derivatization was applied to eliminate the interferents and make the analytes amenable for UV detection. Thereafter, chromatographically separated derivatives were trapped on on-line SPE cartridges. They were subsequently eluted and 1H NMR and COSY spectra were obtained. The overall detection limits of the LC-UV-SPE-NMR method for the mentioned analytes were found to be 18, 23, 25, and 32 mg/L respectively. Applicability of the method to real samples was demonstrated by the analysis of samples provided during the 22nd OPCW official proficiency test. The method gave reproducible NMR spectra devoid of intense background signals. PMID:20303089

  8. Feshbach Resonances in Ultracold Gases

    NASA Astrophysics Data System (ADS)

    Kokkelmans, Servaas

    2015-09-01

    In this chapter, we describe scattering resonance phenomena in general, and focus on the mechanism of Feshbach resonances, for which a multi-channel treatment is required. We derive the dependence of the scattering phase shift on magnetic field and collision energy. From this, the scattering length and effective range coefficient can be extracted -- expressions which are particularly useful for ultracold gases.

  9. Extraction of overt verbal response from the acoustic noise in a functional magnetic resonance imaging scan by use of segmented active noise cancellation.

    PubMed

    Jung, Kwan-Jin; Prasad, Parikshit; Qin, Yulin; Anderson, John R

    2005-03-01

    A method to extract the subject's overt verbal response from the obscuring acoustic noise in an fMRI scan is developed by applying active noise cancellation with a conventional MRI microphone. Since the EPI scanning and its accompanying acoustic noise in fMRI are repetitive, the acoustic noise in one time segment was used as a reference noise in suppressing the acoustic noise in subsequent segments. However, the acoustic noise from the scanner was affected by the subject's movements, so the reference noise was adaptively adjusted as the scanner's acoustic properties varied in time. This method was successfully applied to a cognitive fMRI experiment with overt verbal responses. PMID:15723385

  10. A comparative study of feature extraction and blind source separation of independent component analysis (ICA) on childhood brain tumour 1H magnetic resonance spectra.

    PubMed

    Hao, Jie; Zou, Xin; Wilson, Martin P; Davies, Nigel P; Sun, Yu; Peet, Andrew C; Arvanitis, Theodoros N

    2009-10-01

    Independent component analysis (ICA) has the potential of determining automatically the metabolite signals which make up MR spectra. However, the reliability with which this is accomplished and the optimal approach for investigating in vivo MRS have not been determined. Furthermore, the properties of ICA in brain tumour MRS with respect to dataset size and data quality have not been systematically explored. The two common techniques for applying ICA, blind source separation (BSS) and feature extraction (FE) were examined in this study using simulated data and the findings confirmed on patient data. Short echo time (TE 30 ms), low and high field (1.5 and 3 T) in vivo brain tumour MR spectra of childhood astrocytoma, ependymoma and medulloblastoma were generated by using a quantum mechanical simulator with ten metabolite and lipid components. Patient data (TE 30 ms, 1.5 T) were acquired from children with brain tumours. ICA of simulated data shows that individual metabolite components can be extracted from a set of MRS data. The BSS method generates independent components with a closer correlation to the original metabolite and lipid components than the FE method when the number of spectra in the dataset is small. The experiments also show that stable results are achieved with 300 MRS at an SNR equal to 10. The FE method is relatively insensitive to different ranges of full width at half maximum (FWHM) (from 0 to 3 Hz), whereas the BSS method degrades on increasing the range of FWHM. The peak frequency variations do not affect the results within the range of +/-0.08 ppm for the FE method, and +/-0.05 ppm for the BSS method. When the methods were applied to the patient dataset, results consistent with the synthesized experiments were obtained. PMID:19431141

  11. A derivatization strategy for the detection and identification of volatile trialkylphosphites using liquid chromatography-online solid phase extraction and offline nuclear magnetic resonance spectroscopy.

    PubMed

    Mazumder, Avik; Gutch, Pranav K; Dubey, Devendra K

    2015-05-01

    We demonstrate herein the application of selective derivatization method that converts volatile and labile trialkylphosphites (TAPs) into virtually non-volatile, thermally stable, and UV absorbing derivatives. After simple sample preparation, purification/enrichment of the derivatives was achieved by using high performance liquid chromatography (HPLC) coupled to on-line post column solid phase extraction (SPE) system. These derivatives were subjected to (31)P{(1)H} NMR and 1D-selTOCSY experiments. Conclusive identification was achieved on the basis of their HPLC retention time and NMR spectral signatures ( [Formula: see text] , (n)JH-H, and (3)JP-H). This method was tested for the unambiguous identification of a mixture containing low concentrations (?10?gmL(-1)) of trimethylphosphite (TMP), triethylphosphite (TEP), triisopropylphosphite (TIP), and tributylphosphite (TBP) along with a high concentration of irrelevant background chemicals. It offered a high dynamic range and good detection limit and recovery (>75%) without the need for special NMR probe heads or exotic NMR experiments. PMID:25840658

  12. Analysis of sesquiterpene lactones, lignans, and flavonoids in wormwood (Artemisia absinthium L.) using high-performance liquid chromatography (HPLC)-mass spectrometry, reversed phase HPLC, and HPLC-solid phase extraction-nuclear magnetic resonance.

    PubMed

    Aberham, Anita; Cicek, Serhat Sezai; Schneider, Peter; Stuppner, Hermann

    2010-10-27

    Today, the medicinal use of wormwood (Artemisia absinthium) is enjoying a resurgence of popularity. This study presents a specific and validated high-performance liquid chromatography (HPLC)-diode array detection method for the simultaneous determination and quantification of bioactive compounds in wormwood and commercial preparations thereof. Five sesquiterpene lactones, two lignans, and a polymethoxylated flavonoid were baseline separated on RP-18 material, using a solvent gradient consisting of 0.085% (v/v) o-phosphoric acid and acetonitrile. The flow rate was 1.0 mL/min, and chromatograms were recorded at 205 nm. The stability of absinthin was tested exposing samples to light, moisture, and different temperatures. Methanolic and aqueous solutions of absinthin were found to be stable for up to 6 months. This was also the case when the solid compound was kept in the refrigerator at -35 °C. In contrast, the colorless needles, when stored at room temperature, turned yellow. Three degradation compounds (anabsin, anabsinthin, and the new dimer 3'-hydroxyanabsinthin) were identified by HPLC-mass spectrometry and HPLC-solid-phase extraction-nuclear magnetic resonance and quantified by the established HPLC method. PMID:20886883

  13. Fluorescence resonance energy transfer-based real-time polymerase chain reaction method without DNA extraction for the genotyping of F5, F2, F12, MTHFR, and HFE.

    PubMed

    Martinez-Serra, Jordi; Robles, Juan; Nicolàs, Antoni; Gutierrez, Antonio; Ros, Teresa; Amat, Juan Carlos; Alemany, Regina; Vögler, Oliver; Abelló, Aina; Noguera, Aina; Besalduch, Joan

    2014-01-01

    Blood samples are extensively used for the molecular diagnosis of many hematological diseases. The daily practice in a clinical laboratory of molecular diagnosis in hematology involves using a variety of techniques, based on the amplification of nucleic acids. Current methods for polymerase chain reaction (PCR) use purified genomic DNA, mostly isolated from total peripheral blood cells or white blood cells (WBC). In this paper we describe a real-time fluorescence resonance energy transfer-based method for genotyping directly from blood cells. Our strategy is based on an initial isolation of the WBCs, allowing the removal of PCR inhibitors, such as the heme group, present in the erythrocytes. Once the erythrocytes have been lysed, in the LightCycler(®) 2.0 Instrument, we perform a real-time PCR followed by a melting curve analysis for different genes (Factors 2, 5, 12, MTHFR, and HFE). After testing 34 samples comparing the real-time crossing point (CP) values between WBC (5×10(6) WBC/mL) and purified DNA (20 ng/?L), the results for F5 Leiden were as follows: CP mean value for WBC was 29.26±0.566 versus purified DNA 24.79±0.56. Thus, when PCR was performed from WBC (5×10(6) WBC/mL) instead of DNA (20 ng/?L), we observed a delay of about 4 cycles. These small differences in CP values were similar for all genes tested and did not significantly affect the subsequent analysis by melting curves. In both cases the fluorescence values were high enough, allowing a robust genotyping of all these genes without a previous DNA purification/extraction. PMID:25028568

  14. 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.

  15. Resonance scraping

    SciTech Connect

    Collins, T.

    1986-06-01

    Protons lost in a ring leave at a few preferred locations, determined by some non-linear property of the dipoles. This paper suggests taking control of lost protons by beating the magnets at their own game - by means of a designed resonance used as a beam scraper. It is a study of suitable resonances, including estimates of the required multipole element strengths. The appropriate resonances are two-dimensional. A large number of figures is included.

  16. Unstable resonator with canceling edge waves

    Microsoft Academic Search

    M. E. Smithers; T. C. Salvi; G. C. Dente

    1982-01-01

    It is pointed out that unstable optical resonators offer large mode volumes and high extraction ratios combined with good beam quality. They are distinguished by an output which expands around rather than passing through the output mirror. These properties make them especially attractive for high-energy laser applications. However, diffractive scattering back into the resonator from the sharp aperture at the

  17. Gravitoelectromagnetic resonances

    Microsoft Academic Search

    Christos G. Tsagas

    2011-01-01

    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, gravitoelectromagnetic resonances have been investigated as a means of more efficient gravity-wave detection methods. In this report, we consider the coupling between

  18. Injection and extraction for cyclotrons

    E-print Network

    Kleeven, W

    2006-01-01

    The main design goals for beam injection are explained and special problems related to a central region with internal ion source are considered. The principle of a PIG source is addressed. The issue of vertical focusing in the cyclotron centre is briefly discussed. Several examples of numerical simulations are given. Different ways of (axial) injection are briefly outlined. A proposal for a magnetostatic axial inflector is given. Different solutions for beam extraction are treated. These include the internal target, extraction by stripping, resonant extraction using a deflector and self-extraction. The different ways of creating a turn-separation are explained. The purpose of different types of extraction devices such as harmonic coils, deflectors and gradient corrector channels are outlined. Several illustrations are given in the form of photographs and drawings.

  19. Magnetic Resonance

    Cancer.gov

    Focus Group on Magnetic Resonance Spectroscopy (MRS) in Clinical Oncology(April 1999) To explore the technical requirements for MRS and the application of hydrogen and multinuclear spectroscopy for tumor response to therapy.

  20. Differential cross section and polarization extractions for gamma p going to K+sigma0 and gamma p going to phi p using CLAS at Jefferson Lab, towards a partial wave analysis in search of missing baryon resonances

    NASA Astrophysics Data System (ADS)

    Dey, Biplab

    In the first part of this work, we present differential cross section and polarization measurements for the reactions gammap ? K+Sigma0 and gammap ? ?p. The data were collected using the large-acceptance CLAS detector stationed in Ball B at Jefferson Lab. An unpolarized energy-tagged photon beam produced via bremsstrahlung and a liquid hydrogen cryotarget was used for this, during the so-called g11a experimental run-period. The kinematic coverage of our results is from near production threshold to s = 2.84 GeV in energy and -0.95 ? costhetac.m. ? +0.95 in the meson production angle thetac.m.. For the most part, our results are finely binned in 10-MeV-wide s bins. For the ?p channel, we analyze both the charged (? ? K+K -) and the neutral (? ? K0SK0L ) decay modes. For K+Sigma 0, our work corresponds to a 300 MeV increase in energy coverage for the differential cross sections and forms the first extensive recoil polarization world dataset. For ?p, where previous world data is either non-existent or exist with wide energy bins and very limited statistics, our results will be the first extensive world dataset for both the cross sections and the spin density matrix elements r0MM' . Our K+Sigma0 results are now published as PRC 82, 025202 (2010) [1] and the ?p results are also nearing completion of internal Collaboration analysis review. In addition, we have also been able to extend upon a previous K+? analysis in the backward-angles and near-threshold kinematic regimes, using a higher statistics dataset. The second segment consists of setting up a general framework for performing a coupled-channel partial wave analysis (PWA) on these extracted data results. Our final goal is to search for the so-called "missing" baryon resonances, that is, states predicted by quark models, but absent in conventional piN analyses. We construct the amplitudes and polarization observables required for this PWA. For polarizations in the pseudo-scalar sector, sign discrepancies due to different conventions adopted by different authors in the field are treated in a systematic manner and this study has been published as PRC 83, 055208 (2011) [2]. During our preliminary PWA, we found that certain normalization discrepancies exist between CLAS and older higher energy data from SLAC/DESY/CEA. A systematic global study of these normalization issues and their effect on the coupling constants in hadrodynamic model is presented. Our PWA is an ongoing work and the rich set of data results and analysis tools obtained here will provide a strong impetus for continuing investigations.

  1. Tooth Extraction

    MedlinePLUS

    ... the immune system. Wisdom teeth , also called third molars, are often extracted either before or after they ... sinus during removal of an upper back tooth (molar) — A small hole usually will close up by ...

  2. DNA Extraction

    NSDL National Science Digital Library

    Janice Stephens

    2011-01-01

    In this activity related to plant biotechnology, learners extract DNA from fruit to investigate how it looks and feels. The procedure is similar to what scientists have to do before they can use information contained in this DNA. This lesson guide includes procedure and discussion questions to help learners reflect on the process and purpose of DNA extraction. Modifications for younger learners are included in a related PDF (see related resources).

  3. 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

  4. 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.

  5. 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.

  6. Resonance conditions

    E-print Network

    P. Rebusco

    2005-10-14

    Non-linear parametric resonances occur frequently in nature. Here we summarize how they can be studied by means of perturbative methods. We show in particular how resonances can affect the motion of a test particle orbiting in the vicinity of a compact object. These mathematical toy-models find application in explaining the structure of the observed kHz Quasi-Periodic Oscillations: we discuss which aspects of the reality naturally enter in the theory, and which one still remain a puzzle.

  7. Resonance production

    NASA Astrophysics Data System (ADS)

    Fachini, Patricia

    2004-08-01

    Recent results on rgr(770)0, K(892)*0, f0(980), phgr(1020), Dgr(1232)++ and Lgr(1520) production in A+A and p+p collisions at SPS and RHIC energies are presented. These resonances are measured via their hadronic decay channels and used as a sensitive tool to examine the collision dynamics in the hadronic medium through their decay and regeneration. The modification of resonance mass, width and shape due to phase space and dynamical effects are discussed.

  8. Statistical properties of resonance states in a double Morse potential well

    Microsoft Academic Search

    S. Dallwig; I. Weese; Th. Weiss; Ch. Schlier

    1996-01-01

    The resonances of a collinear ABA molecule with a double Morse potential well are computed by means of complex scaling. For each symmetry, this system has about 40 resonances in 10 channels. The extraction of the resonance parameters from the raw data has been automatized, allowing the computation of all resonances for more than 40 values of the kinetic coupling

  9. Autostereogram resonators

    NASA Astrophysics Data System (ADS)

    Leavey, Sean; Rae, Katherine; Murray, Adam; Courtial, Johannes

    2012-09-01

    Autostereograms, or "Magic Eye" pictures, are repeating patterns designed to give the illusion of depth. Here we discuss optical resonators that create light patterns which, when viewed from a suitable position by a monocular observer, are autostereograms of the three-dimensional shape of one of the mirror surfaces.

  10. Extractant composition

    DOEpatents

    Smith, Barbara F. (Los Alamos, NM); Jarvinen, Gordon D. (Los Alamos, NM); Ryan, Robert R. (Los Alamos, NM)

    1990-01-01

    An organic extracting solution useful for separating elements of the actinide series of the periodic table from elements of the lanthanide series, where both are in trivalent form. The extracting solution consists of a primary ligand and a secondary ligand, preferably in an organic solvent. The primary ligand is a substituted monothio-1,3-dicarbonyl, which includes a substituted 4-acyl-2-pyrazolin-5-thione, such as 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT). The secondary ligand is a substituted phosphine oxide, such as trioctylphosphine oxide (TOPO).

  11. Gravitoelectromagnetic resonances

    NASA Astrophysics Data System (ADS)

    Tsagas, Christos G.

    2011-08-01

    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, gravitoelectromagnetic 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, gravitoelectromagnetic 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.

  12. 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…

  13. Contrasting Extraction Types.

    ERIC Educational Resources Information Center

    Postal, Paul M.

    1994-01-01

    This paper grounds a novel typology yielding three major types of English (L(eft)-extraction, defined by their relationship to resumptive pronouns (RPs): (1) B-extractions, which require RPs in their extraction sites, (2) A1-extractions, which allow RPs in their extraction sites, and (3) A2-extractions, which forbid RPs in their extraction sites.…

  14. Magnetic resonance image enhancement using V-filter

    SciTech Connect

    Yamamoto, H.; Sugita, K. (School of Health Sciences, Okayama Univ., Shikata, Okayama 700 (JP)); Kanzaki, N.; Johja, I.; Hiraki, Y. (Okayama Univ. (Japan). School of Medicine); Kuwahara, M. (Osaka Industrial Univ., Nakagaito, Daito 574 (JP))

    1990-06-01

    The purpose of this study is to present a method of boundary enhancement algorithms for magnetic resonance images using a V-filter. The boundary of the brain tumor was precisely extracted by the region segmentation techniques.

  15. Heavy ion excitation and photon decay of giant resonances

    SciTech Connect

    Bertrand, F.E.; Beene, J.R.; Sjoreen, T.P.

    1983-01-01

    Results are presented for excitation of giant multipole resonances by inelastic scattering of 350 and 500 MeV /sup 16/O projectiles from /sup 90/Zr and /sup 208/Pb. The giant quadrupole resonance is excited with large cross sections and a very large resonance peak to continuum ratio is obtained. Extracted cross sections agree with DWBA calculations which use standard collective model form factors. Using 380 MeV 170 to excite the giant resonances, the ..gamma..-ray decay has been measured for the giant quadrupole resonance region of /sup 208/Pb. 10 references.

  16. Features of power extraction in EOIL

    NASA Astrophysics Data System (ADS)

    Mezhenin, Andrey V.; Azyazov, Valeriy N.

    2015-02-01

    The single-frequency two-level (SFTL) generation model was applied to predict the power extraction efficiency in electrically driven oxygen-iodine laser (EOIL). The analysis of the calculated and published experimental data showed that power extraction from the cw EOIL is limited by the rate of energy transfer from singlet oxygen molecules O2(1?) to iodine atoms I(2P3/2) and about half of the produced singlet oxygen molecules were carried out from the resonator. To increase power extraction efficiency it will be necessary to substantially extend concentrations of singlet oxygen molecules and iodine atoms in the active medium of EOIL.

  17. Neutron Skin and Giant Resonances in Nuclei

    E-print Network

    Vadim Rodin

    2007-04-02

    Some aspects, both experimental and theoretical, of extracting the neutron skin $\\Delta R$ from properties of isovector giant resonances are discussed. Existing proposals are critically reviewed. The method relying on the energy difference between the GTR and IAS is shown to lack sensitivity to $\\Delta R$. A simple explanation of the linear relation between the symmetry energy and the neutron skin is also given.

  18. Internal friction studies by resonant ultrasound spectroscopy

    Microsoft Academic Search

    R. G. Leisure; K. Foster; J. E. Hightower; D. S. Agosta

    2004-01-01

    A description is given of the use of resonant ultrasound spectroscopy (RUS) to study internal friction in solids. The technique is applicable to a wide range of sample sizes and shapes. A method to extract the internal friction from the RUS spectrum in the presence of a coherent background signal is discussed. RUS has been used to study the internal

  19. Resonant ultrasound spectroscopy and homogeneity in polycrystals

    Microsoft Academic Search

    Gunes Kaplan; T. W. Darling; K. R. McCall

    2009-01-01

    Resonant ultrasound spectroscopy (RUS) is capable of determining the bulk elastic properties of a solid from its characteristic vibration frequencies, given the dimensions, density and shape of the sample. The model used for extracting values of the elastic constants assumes perfect homogeneity, which can be approximated by average–isotropic polycrystals. This approximation is excellent in the small grain regime assumed for

  20. Regenerative feedback resonant circuit

    DOEpatents

    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.

  1. Magnetic resonance angiography

    MedlinePLUS

    MRA; Angiography - magnetic resonance ... Kwong RY. Cardiovascular Magnetic Resonance Imaging. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . ...

  2. Improved longitudinal EMAT transducer for elastic constant extraction

    Microsoft Academic Search

    Maurício Pereira da Cunha; Jared W. Jordan

    2005-01-01

    Elastic constants are extracted by measuring the shear and longitudinal bulk acoustic wave (BAW) velocities along several crystal orientations. Rapid, precise measurement of crystal elastic properties are fundamental in the evaluation of new materials for the fabrication of acoustic wave based filters and resonators. The extraction of elastic constants can be done by the use of external piezoelectric transducers in

  3. Extraction of Dicarboxylic Acids by ABC Extractants

    Microsoft Academic Search

    N. Syzova; A. M. Eyal; A. Vitner; B. Hazan

    2004-01-01

    Extraction of various dicarboxylic acids (maleic, malic, malonic, succinic, and tartaric) by acid–base couple (ABC) extractants was studied. The main extraction mechanisms were found to be ion?pair and hydrogen?bond formation. The relative contribution of each mechanism and extraction efficiency were found to be controlled by parameters such as acid–base properties and hydrogen?bonding capability of the components of the ABC extractants

  4. Parameter extraction from fabricated silicon photonic devices.

    PubMed

    Chen, Xi; Li, Zheng; Mohamed, Moustafa; Shang, Li; Mickelson, Alan R

    2014-03-01

    Three sets of devices were simulated, designed, and laid out for fabrication in the EuroPractice shuttle program and then measured in-house after fabrication. A combination of analytical and numerical modeling is used to extract the dispersion curves that define the effective index of refraction as a function of wavelength for three different classes of silicon photonic devices, namely, micro-ring resonators, racetrack resonators, and directional couplers. The results of this phenomenological study are made plausible by the linearity of the extracted dispersion curves with wavelength over the wavelength regime of interest (S and C bands) and the use of the determined effective indices to reconstruct the measured transmission as a function of wavelength curves in close agreement with experiment. The extracted effective indices can be used to place limits on the actual fabricated values of waveguide widths, thicknesses, radii of curvature, and coupling gaps. PMID:24663369

  5. Texture Coding in the Rat Whisker System: Slip-Stick Versus Differential Resonance

    Microsoft Academic Search

    Jason Wolfe; Dan N. Hill; Sohrab Pahlavan; Patrick J. Drew; David Kleinfeld; Daniel E. Feldman

    2008-01-01

    Rats discriminate surface textures using their whiskers (vibrissae), but how whiskers extract texture information, and how this information is encoded by the brain, are not known. In the resonance model, whisker motion across different textures excites mechanical resonance in distinct subsets of whiskers, due to variation across whiskers in resonance frequency, which varies with whisker length. Texture information is therefore

  6. 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

  7. Unstable resonators with excited converging wave

    SciTech Connect

    Hodgson, N. (Optisches Institut, Technische Universitat Berlin, Strasse des 17. Juni 135, 1000 Berlin 12 (DE)); Weber, H. (Festkoerper-Laser-Institut Berlin GmbH, Strasse des 17, Juni 135, 1000 Berlin (DE))

    1990-04-01

    This paper reports the properties of unstable resonators with an additional mirror inside or outside the resonator investigated, both experimentally and theoretically. The additional mirror excites the converging wave, and by this, output coupling is decreased without affecting beam quality. Experiments were performed with a pulsed Nd:YAG system. The theoretical model was based on the coupled Kirchhoff integrals and solved numerically. Agreement between theory and experiments indicates that this kind of resonator provides high focusability and maximum extraction efficiency simultaneously, even with low-gain media. This enables one to apply unstable resonators to solid-state lasers with low small-signal gain, like alexandrite or CW-pumped Nd:YAG.

  8. Unstable resonator with canceling edge waves

    NASA Astrophysics Data System (ADS)

    Smithers, M. E.; Salvi, T. C.; Dente, G. C.

    1982-02-01

    It is pointed out that unstable optical resonators offer large mode volumes and high extraction ratios combined with good beam quality. They are distinguished by an output which expands around rather than passing through the output mirror. These properties make them especially attractive for high-energy laser applications. However, diffractive scattering back into the resonator from the sharp aperture at the edge of the output mirror significantly affects the resonator modes. A design is proposed which greatly reduces the effect of edge diffraction on the resonator modes. The design concept involves the introduction of a second discontinuity in the surface of the feedback mirror. This discontinuity, which can be a phase step, then serves as another source of edge waves which interfere with the waves from the outer edge. The position and strength of the internal discontinuity are chosen to produce cancellation of the edge waves at the geometric source point. This reduces the effect of edge diffraction.

  9. Apparatus for hydrocarbon extraction

    DOEpatents

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  10. 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

  11. Photoacoustic resonance spectroscopy for biological tissue characterization

    NASA Astrophysics Data System (ADS)

    Gao, Fei; Feng, Xiaohua; Zheng, Yuanjin; Ohl, Claus-Dieter

    2014-06-01

    By "listening to photons," photoacoustics allows the probing of chromosomes in depth beyond the optical diffusion limit. Here we report the photoacoustic resonance effect induced by multiburst modulated laser illumination, which is theoretically modeled as a damped mass-string oscillator and a resistor-inductor-capacitor (RLC) circuit. Through sweeping the frequency of multiburst modulated laser, the photoacoustic resonance effect is observed experimentally on phantoms and porcine tissues. Experimental results demonstrate different spectra for each phantom and tissue sample to show significant potential for spectroscopic analysis, fusing optical absorption and mechanical vibration properties. Unique RLC circuit parameters are extracted to quantitatively characterize phantom and biological tissues.

  12. 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.

  13. Optical Fano resonance of an individual semiconductor nanostructure

    NASA Astrophysics Data System (ADS)

    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.

  14. Crossing simple resonances

    SciTech Connect

    Collins, T.

    1985-08-01

    A simple criterion governs the beam distortion and/or loss of protons on a fast resonance crossing. Results from numerical integrations are illustrated for simple sextupole, octupole, and 10-pole resonances.

  15. Nanomechanical resonance detector

    DOEpatents

    Grossman, Jeffrey C; Zettl, Alexander K

    2013-10-29

    An embodiment of a nanomechanical frequency detector includes a support structure and a plurality of elongated nanostructures coupled to the support structure. Each of the elongated nanostructures has a particular resonant frequency. The plurality of elongated nanostructures has a range of resonant frequencies. An embodiment of a method of identifying an object includes introducing the object to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the object. An embodiment of a method of identifying a molecular species of the present invention includes introducing the molecular species to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the molecular species.

  16. MRI (Magnetic Resonance Imaging)

    MedlinePLUS

    ... Radiation-Emitting Products and Procedures Medical Imaging MRI (Magnetic Resonance Imaging) Description Uses Risks/Benefits Information for ... Regulations & Performance Standards Industry Guidance Other Resources Description Magnetic resonance imaging (MRI) is a medical imaging procedure ...

  17. Alkaline extraction of wastewater activated sludge biosolids.

    PubMed

    García Becerra, Flor Y; Acosta, Edgar J; Allen, D Grant

    2010-09-01

    Activated sludge produced by wastewater treatment facilities are a sub-utilized by-product whose handling and disposal represent significant costs to these facilities. In this work, we introduced a simple and effective alkaline extraction technique that extracts up to 75% of the sludge's organic matter into a liquor containing potentially useful organic material (proteins, carbohydrates, etc.). The results suggest that at pH 11 and above, cell lysis occurs, liberating substantial quantities of organic material into the alkaline solution. When compared to a cation exchange resin (CER) extraction developed for analytical purposes, the alkaline extraction recovered 3x more organic material. The alkaline extract was highly surface active, despite containing a relatively small fraction of lipids. At pH 12 and above the lipid fraction was enriched with C15-C16 fatty acid residues, likely associated with cell membrane phospholipids as suggested by nuclear magnetic resonance spectroscopy ((31)P NMR). Size exclusion chromatography studies show that the extract is enriched with biopolymers or assemblies of molecular weights in the order of tens of thousands of Daltons. Potential uses for the extract are discussed. PMID:20435473

  18. Optically Enhanced Magnetic Resonance

    E-print Network

    Suter, Dieter

    Optically Enhanced Magnetic Resonance Dieter Suter Universit¨at Dortmund, Germany 1 Introduction 1.1 Motivation The physical mechanism of nuclear magnetic resonance spectroscopy, the excitation of transitions. In most magnetic resonance experiments, these couplings are used to monitor the environment of the nuclei

  19. Magnetic Resonance Spectroscopy (MRS)

    E-print Network

    Mandal, Pravat K.

    Magnetic Resonance Spectroscopy (MRS) and Its Application in Alzheimer's Disease PRAVAT K. MANDAL1, Pennsylvania ABSTRACT: Magnetic resonance spectroscopy (MRS) is a noninvasive tool to measure the chemical; PRESS; STEAM; 2D MRS; Alzheimer's disease I. INTRODUCTION Magnetic resonance spectroscopy (MRS) is a rap

  20. 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.

  1. ELECTRON PARAMAGNETIC RESONANCE SPECTROSCOPY

    E-print Network

    Crofts, Antony R.

    CHAPTER 3 ELECTRON PARAMAGNETIC RESONANCE SPECTROSCOPY 1 Sergei A. Dikanov and 2 Antony R. Crofts 1 for the investigation of unpaired electron spins. Two terms are used in the literature: electron paramagnetic resonance (EPR) and electron spin resonance (ESR). We will use the first term in this chapter. During the sixty

  2. An Inexpensive Resonance Demonstration

    ERIC Educational Resources Information Center

    Dukes, Phillip

    2005-01-01

    The phenomenon of resonance is applicable to almost every branch of physics. Without resonance, there wouldn't be televisions or stereos, or even swings on the playground. However, resonance also has undesirable side effects such as irritating noises in the car and the catastrophic events such as helicopters flying apart. In this article, the…

  3. Resonance transformer power conditioners

    Microsoft Academic Search

    R. M. Ness; S. G. E. Pronko; J. R. Cooper; E. Y. Chu

    1990-01-01

    Designs for power conditioning systems based on the resonance transformer have been developed for applications requiring compact, lightweight power supplies ranging from average power levels of 10 kW to over 1 MW. The resonance transformer is a patented concept which depends on a set of resonant LC circuits to produce transformer-like voltage or current gain. Because this approach does not

  4. [Magnetic resonance spectroscopy].

    PubMed

    Tsa?, I V; Kulikov, S A; Kozinets, G I

    2001-06-01

    Life-time diagnosis of the initial pathological shifts in the organism remains an and still unsolved important problem of modern medicine. Magnetic resonance spectroscopy based on the nuclear magnetic resonance phenomenon is one of the methods which can help to solve this problem. Modern reports about the use of magnetic resonance spectroscopy in the diagnosis of various diseases are reviewed. PMID:11521591

  5. 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.

  6. 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.

  7. 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.

  8. Molecular dynamics investigation of carbon nanotube resonance

    NASA Astrophysics Data System (ADS)

    Chang, I.-Ling

    2013-06-01

    In this work, a methodology to directly extract resonant information from an equilibrium molecular dynamics simulation is proposed and demonstrated by analyzing the vibrational behavior of carbon nanotubes (CNTs). Different vibrational motions, i.e. longitudinal, transverse, rotational and radial, could be easily distinguished and computed through the time sequence of the velocity components of atoms at the equilibrating process. Fast Fourier transform is adopted to perform the transformation of vibration information from time to frequency domain. The effects of CNT length, radius and boundary condition on the resonant behaviors of CNTs are systematically investigated. Moreover, the simulation results are compared with those predicted based on the Euler-Bernoulli beam theory. Note that the simulated longitudinal and rotational resonant behaviors agree quite well with the theoretical prediction and a slight deviation is observed in the transverse prediction.

  9. Resonant and non-resonant magnetic scattering

    SciTech Connect

    McWhan, D.B.; Hastings, J.B.; Kao, C.C.; Siddons, D.P.

    1991-01-01

    The tunability and the polarization of synchrotron radiation open upon new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and thy fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measure the spin polarized density of states. The production and analysis of polarized beams are discussed in the context of the study of magnetism with synchrotron radiation.

  10. Resonant and non-resonant magnetic scattering

    SciTech Connect

    McWhan, D.B.; Hastings, J.B.; Kao, C.C.; Siddons, D.P.

    1991-12-31

    The tunability and the polarization of synchrotron radiation open upon new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and thy fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measure the spin polarized density of states. The production and analysis of polarized beams are discussed in the context of the study of magnetism with synchrotron radiation.

  11. 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.

  12. Fabry-Pérot resonances in one-dimensional plasmonic nanostructures.

    PubMed

    Dorfmüller, Jens; Vogelgesang, Ralf; Weitz, R Thomas; Rockstuhl, Carsten; Etrich, Christoph; Pertsch, Thomas; Lederer, Falk; Kern, Klaus

    2009-06-01

    We study the near-field optical behavior of Fabry-Pérot resonances in thin metal nanowires, also referred to as quasi one-dimensional plasmonic nanoantennas. From eigenmodes well beyond quadrupolar order we extract both, propagation constant and reflection phase of the guided surface plasmon polariton with superb accuracy. The combined symmetry breaking effects of oblique illumination and retardation allow the excitation of dipole forbidden, even order resonances. All measurements are supported by rigorous simulations of the experimental situation. PMID:19472987

  13. 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.

  14. A proton nuclear magnetic resonance study of sulfmyoglobin cyanide.

    PubMed

    Magliozzo, R S; Peisach, J

    1986-07-25

    The proton nuclear magnetic resonance spectrum of sulfmyoglobin cyanide was studied at 400 MHz. The position of a methyl-group resonance at low field is consistent with a chlorin-like structure for the prosthetic group. The proton NMR spectrum of the cyanide derivative of the purified prosthetic group which decomposes upon extraction from the protein was found to be the same as that of the cyanide derivative of the prosthetic group extracted from myoglobin and a sample prepared from hemin-Cl. PMID:3730393

  15. Fast robust automated brain extraction.

    PubMed

    Smith, Stephen M

    2002-11-01

    An automated method for segmenting magnetic resonance head images into brain and non-brain has been developed. It is very robust and accurate and has been tested on thousands of data sets from a wide variety of scanners and taken with a wide variety of MR sequences. The method, Brain Extraction Tool (BET), uses a deformable model that evolves to fit the brain's surface by the application of a set of locally adaptive model forces. The method is very fast and requires no preregistration or other pre-processing before being applied. We describe the new method and give examples of results and the results of extensive quantitative testing against "gold-standard" hand segmentations, and two other popular automated methods. PMID:12391568

  16. Enhanced light extraction from circular Bragg grating coupled microcavities

    NASA Astrophysics Data System (ADS)

    Su, Mark Y.; Mirin, Richard P.

    2006-07-01

    A sevenfold enhancement of light extraction over a 130nm bandwidth from a semiconductor at room temperature was achieved using circular Bragg gratings (CBGs) etched around the periphery of a vertical-cavity light-emitting structure. The CBG defined an in-plane circular cavity for light trapped in guided modes. Maximum enhancement was observed with CBGs that efficiently coupled circular cavity modes into resonant extracted modes of the vertical cavity. The enhancement factor corresponded to a 41% external efficiency.

  17. PITFALLS OF SEQUENTIAL EXTRACTION

    EPA Science Inventory

    An increasing number of researchers are using sequential extraction to determine the speciation of trace elements in sediments. nfortunately, sequential extraction methods have not been successfully validated. he results are simply taken as providing "operational definitions" of ...

  18. Grape Seed Extract

    MedlinePLUS

    ... Extract Common Name: grape seed extract Latin Name: Vitis vinifera grapes.jpg © Steven Foster On this page: What ... naturaldatabase.com on June 25, 2009. Grape seed ( Vitis vinifera, Vitis coignetiae ). Natural Standard Database Web site. Accessed ...

  19. Mistletoe Extracts (PDQ)

    MedlinePLUS

    ... Trials Cancer Statistics Research & Funding News About NCI Mistletoe Extracts (PDQ®) Patient Version Health Professional Version Last Modified: 02/20/2014 Mistletoe Extracts (PDQ®) Overview Questions and Answers About Mistletoe ...

  20. Exhaustive extraction of peptides by electromembrane extraction.

    PubMed

    Huang, Chuixiu; Gjelstad, Astrid; Pedersen-Bjergaard, Stig

    2015-01-01

    This fundamental work illustrates for the first time the possibility of exhaustive extraction of peptides using electromembrane extraction (EME) under low system-current conditions (<50 ?A). Bradykinin acetate, angiotensin II antipeptide, angiotensin II acetate, neurotensin, angiotensin I trifluoroacetate, and leu-enkephalin were extracted from 600 ?L of 25 mM phosphate buffer (pH 3.5), through a supported liquid membrane (SLM) containing di-(2-ethylhexyl)-phosphate (DEHP) dissolved in an organic solvent, and into 600 ?L of an acidified aqueous acceptor solution using a thin flat membrane-based EME device. Mass transfer of peptides across the SLM was enhanced by complex formation with the negatively charged DEHP. The composition of the SLM and the extraction voltage were important factors influencing recoveries and current with the EME system. 1-nonanol diluted with 2-decanone (1:1 v/v) containing 15% (v/v) DEHP was selected as a suitable SLM for exhaustive extraction of peptides under low system-current conditions. Interestingly, increasing the SLM volume from 5 to 10 ?L was found to be beneficial for stable and efficient EME. The pH of the sample strongly affected the EME process, and pH 3.5 was found to be optimal. The EME efficiency was also dependent on the acceptor solution composition, and the extraction time was found to be an important element for exhaustive extraction. When EME was carried out for 25 min with an extraction voltage of 15 V, the system-current across the SLM was less than 50 ?A, and extraction recoveries for the model peptides were in the range of 77-94%, with RSD values less than 10%. PMID:25467476

  1. Mesonic Content of the Nucleon and the Roper Resonance

    E-print Network

    M. Dillig; M. Schott

    2006-04-24

    We investigate colorless (mesonic) 3q-q qbar components in the nucleon and the Roper resonance N*(1440). Starting from constituent quarks and gluons we estimate the excitation of quark-antiquark pairs in a gluon exchange model with the strong coupling constant extracted from a comparison with a non-perturbative resonating group calculation of the pi, eta, rho and omega content of the nucleon. Applying the same model to the Roper resonance, we find as the most striking result a very strong scalar-isoscalar sigma content of the N*(1440) with a strength of the 3q-q qbar configurations comparable to the 3q component itself.

  2. 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

  3. 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.

  4. Information extraction system

    DOEpatents

    Lemmond, Tracy D; Hanley, William G; Guensche, Joseph Wendell; Perry, Nathan C; Nitao, John J; Kidwell, Paul Brandon; Boakye, Kofi Agyeman; Glaser, Ron E; Prenger, Ryan James

    2014-05-13

    An information extraction system and methods of operating the system are provided. In particular, an information extraction system for performing meta-extraction of named entities of people, organizations, and locations as well as relationships and events from text documents are described herein.

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

    E-print Network

    Knospe, A G

    2015-01-01

    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 phi(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.

  6. 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.

  7. Acoustic Levitator Maintains Resonance

    NASA Technical Reports Server (NTRS)

    Barmatz, M. B.; Gaspar, M. S.

    1986-01-01

    Transducer loading characteristics allow resonance tracked at high temperature. Acoustic-levitation chamber length automatically adjusted to maintain resonance at constant acoustic frequency as temperature changes. Developed for containerless processing of materials at high temperatures, system does not rely on microphones as resonance sensors, since microphones are difficult to fabricate for use at temperatures above 500 degrees C. Instead, system uses acoustic transducer itself as sensor.

  8. On open electromagnetic resonators: relation between interferometers and resonators

    SciTech Connect

    Manenkov, Aleksandr A; Bykov, Vladimir P; Kuleshov, N V [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2010-05-26

    The physical difference between the concepts 'Fabry-Perot interferometer' and 'open resonator' is discussed. It is shown that the use of the term 'Fabry-Perot resonator' for open laser resonators is incorrect both from the historical viewpoint and from the viewpoint of the physical meaning of the processes occurring in these resonators. (laser beams and resonators)

  9. Giant resonance decay

    SciTech Connect

    Beene, J.R.; Bertrand, F.E.

    1990-01-01

    Decay studies of giant multipole resonances are discussed, emphasizing the role of Coulomb excitation with intermediate energy heavy ions, which can provide very large cross sections for both isoscalar and isovector resonances. We discuss measurement of the photon decay of one and two phonon giant resonances, reporting results where available. It is pointed out throughout the presentation that the use of E1 photons as a tag'' provides a means to observe weakly excited resonances that cannot be observed in the singles spectra. 30 refs., 16 figs., 1 tab.

  10. 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.

  11. Microwave characterization of high-temperature superconducting thin films using stripline resonators

    Microsoft Academic Search

    Alan D. Macdonald; Stuart A. Long; Jeffery T. Williams; David R. Jackson; Christopher L. Lichtenberg; Matthew L. Davis; Jaroslaw L. Wosik; John C. Wolfe

    1990-01-01

    A method was derived for the extraction of the surface resistivity (Rs) of high-Tc superconducting (HTS) thin films at microwave frequencies, using a stripline resonator circuit. Surface resistivity values were calculated by measuring the difference in Q-values of a stripline resonator configuration when an HTS thin film was substituted for one of the metallic ground planes. Cryogenic tests were completed

  12. Determination of elastic moduli of rock samples using resonant ultrasound spectroscopy

    Microsoft Academic Search

    Tj Ulrich; K. R. McCall; R. A. Guyer

    2002-01-01

    Resonant ultrasound spectroscopy (RUS) is a method whereby the elastic tensor of a sample is extracted from a set of measured resonance frequencies. RUS has been used successfully to determine the elastic properties of single crystals and homogeneous samples. In this paper, we study the application of RUS to macroscopic samples of mesoscopically inhomogeneous materials, specifically rock. Particular attention is

  13. Fano resonances in prism-coupled multimode square micropillar resonators

    Microsoft Academic Search

    Ho-Tong Lee; Linjie Zhou; Andrew W. Poon

    2005-01-01

    We report Fano resonances in a multimode square glass micropillar resonator; the resonances were obtained by using angle-resolved prism coupling. Our experiments reveal characteristically asymmetric line shapes of high-Q resonances and of detuned low-Q resonances in multimode reflection spectra. The asymmetric resonance line shapes evolve for an approximately pi phase within a 0.5° range of reflection angles. We model our

  14. Perturbed open resonators.

    PubMed

    Barone, S R

    1971-04-01

    The resonant frequencies and diffraction losses of two-mirror open resonators which depart somewhat from an ideal configuration are evaluated by a perturbative technique. Detailed results are derived and discussed for flat mirrors of rectangular or circular aperture with a parabolic phase perturbation as well as flat-roof and conical systems with large apex angle. PMID:20094565

  15. Helioseismology The Resonant Sun

    E-print Network

    Helioseismology The Resonant Sun Professor Bill Chaplin, School of Physics & Astronomy University Eddington #12;The Unseen Interior ''At first sight it would seem that the deep interior of the sun and stars;Overview What are resonant oscillations of the Sun? How do we observe the oscillations? What can we learn

  16. 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.

  17. Ion Cyclotron Resonance Accelerator

    Microsoft Academic Search

    T. L. Grimm; C. T. Ramsell; R. C. York

    1997-01-01

    The Ion Cyclotron Resonance Accelerator (ICRA) is based on the operating principles of cyclotrons and gyrotrons, and should provide beam suitable for the production of radioisotopes for positron emission tomography (PET) or neutrons at a fraction of the cost of present day cyclotrons and linacs. The concept extends cyclotron resonance acceleration to ions by using a superconducting solenoid and a

  18. 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…

  19. Resonant column test

    Microsoft Academic Search

    V. P. Drnevich

    1978-01-01

    The resonant column test is used to determine by vibration the shear modulus, shear damping, rod modulus (Young's modulus) and rod damping of cylindrical specimens of soil in the undisturbed and remolded conditions. The vibration apparatus, apparatus calibration, and calculations are described. The reduction of all resonant column test data is presented in a computer program.

  20. Nuclear magnetic resonance gyroscope

    Microsoft Academic Search

    F. A. Karwacki; J. Griffin

    1985-01-01

    A nuclear magnetic resonance gyroscope which derives angular rotation from the phases of precessing nuclear moments utilizes a single-resonance cel 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 readout beam and associated electronics for signal processing

  1. 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.

  2. Mode conversion losses in silicon-on-insulator photonic wire based racetrack resonators

    Microsoft Academic Search

    Fengnian Xia; Lidija Sekaric; Yurii A. Vlasov

    2006-01-01

    Two complimentary types of SOI photonic wire based devices, the add\\/drop (A\\/D) filter using a racetrack resonator and the Mach-Zehnder interferometer with one arm consisting of an identical resonator in all-pass filter (APF) configuration, were fabricated and characterized in order to extract the optical properties of the resonators and predict the performance of the optical delay lines based on such

  3. An inductively coupled, doubly tuned resonator for in vivo nuclear magnetic resonance spectroscopy

    NASA Astrophysics Data System (ADS)

    McNichols, Roger J.; Wright, Steven M.; Wasser, Jeremy S.; Coté, Gerard L.

    1999-08-01

    We present a coil designed for in vivo 31P and 1H nuclear magnetic resonance spectroscopy which consists of a doubly tuned resonator inductively coupled to separate 1H and 31P feed coils. The advantages of the resonator include the ability to 1H shim over the same volume from which 31P spectra are extracted by using a single sample coil, elimination of coupling problems between separate 1H and 31P coils, ease of design and tuning over conventional double-tuned coils, and reduced match/tune sensitivity to coil loading, which is important in in vivo applications. We have used this coil to collect phosphorus spectra from the in situ heart of the western painted turtle (Chrysemys picta bellii) at 2 T. The total heart volume was less than 1 mL and acquisition time was just under 10 min.

  4. 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.

  5. 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.

  6. 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.

  7. Polaritonic Feshbach resonance

    NASA Astrophysics Data System (ADS)

    Takemura, N.; Trebaol, S.; Wouters, M.; Portella-Oberli, M. T.; Deveaud, B.

    2014-07-01

    A Feshbach resonance occurs when the energy of two interacting free particles comes into resonance with a molecular bound state. When approaching this resonance, marked changes in the interaction strength between the particles can arise. Feshbach resonances provide a powerful tool for controlling the interactions in ultracold atomic gases, which can be switched from repulsive to attractive, and have allowed a range of many-body quantum physics effects to be explored. Here we demonstrate a Feshbach resonance based on the polariton spinor interactions in a semiconductor microcavity. By tuning the energy of two polaritons with anti-parallel spins across the biexciton bound state energy, we show an enhancement of attractive interactions and a prompt change to repulsive interactions. A mean-field two-channel model quantitatively reproduces the experimental results. This observation paves the way for a new tool for tuning polariton interactions and to move forward into quantum correlated polariton physics.

  8. 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.

  9. Efficient utilization of licorice root by alkaline extraction.

    PubMed

    Ohno, Hirokazu; Miyoshi, Shozo; Araho, Daisuke; Kanamoto, Taisei; Terakubo, Shigemi; Nakashima, Hideki; Tsuda, Tadashi; Sunaga, Katsuyoshi; Amano, Shigeru; Ohkoshi, Emika; Sakagami, Hiroshi; Satoh, Kazue; Yamamoto, Masaji

    2014-01-01

    Compared to studies of water extracts of plants, those utilising alkaline extracts are limited. Both water and alkaline extracts from licorice root were compared regarding their biological activities. Licorice root was successively extracted first with water or alkaline solution (pH 9 or 12), and the alkaline (pH 12.0) extract was further separated into 50% ethanol-soluble and -insoluble fractions. Viable cell number was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Antibacterial activity against Porphyromonas gingivalis 381 was determined by turbidity assay. Cytochrome P-450 (CYP)3A4 activity was measured by ?-hydroxylation of testosterone using human recombinant CYP3A4. Radical intensity of superoxide and hydroxyl radicals was determined by electron spin resonance spectroscopy. Alkaline extraction yielded slightly higher amounts of dried materials compared to water extraction. Alkaline extract showed higher anti-HIV and antibacterial activities, and similar magnitudes of CYP3A4 inhibitory and superoxide and hydroxyl radical-scavenging activities, compared to water extract. When alkaline extract was fractionated by 50% ethanol, anti-HIV activity was recovered from the insoluble fraction representing approximately 3% of the alkaline extract, whereas antibacterial activity was concentrated in the soluble fraction rich in glycyrrhizid acid, flavanones and chalcones. All extracts and sub-fractions led to bimodal hormetic dose-response (maximum hormetic response=238%) on the bacterial growth. The present study demonstrated the superiority of alkaline extraction over water extraction for preparing anti-HIV and antibacterial agents at higher yield from licorice root. PMID:25189890

  10. Exploring DNA Extraction Erica Butts

    E-print Network

    Perkins, Richard A.

    · Define DNA extraction · Downstream concerns for DNA extraction · Methods used to evaluate extraction into the extraction process and determine the amount recovered DNA Sources: #12;Applied Genetics Extraction MethodsApplied Genetics Exploring DNA Extraction Efficiency Erica Butts Research Biologist, Applied

  11. Solvent Extract, Plant Extraction Correspondence to Author:

    E-print Network

    Sunil H. Ganatra; Archana M. Ramteke; Shweta P. Durge; S. U. Patil; Dr. S. H. Ganatra

    ABSTRACT: Cyamopsis tetragonoloba L. is belongs to the family Fabaceae. It is used as herbal and as vegetable from ancient times. It is abundant in tropical region of Africa and Asia. Preliminary phytochemicals investigations have been carried out on the seed extract using n-Hexane, Ethyl Acetate, Acetone, Ethanol and Methanol solvents. Qualitative phytochemicals analysis reflects the presence of Phenol, Quinone, Steroid, Flavanoids and Terpenoid in the plant extract. TLC profiling of seed extracts give an idea about the presence of various phytochemicals. Different Rf (Retention factor) value of various phytochemicals provide valuable clue regarding their polarity and selection of solvents for separation of phytochemicals. INTRODUCTION: Cyamopsis tetragonoloba L. (syn. C. psoraloides) or cluster bean (also called as Guar, Guwar and Guvar bean), is a drought-tolerant summer annual legume and it is cultivated as a feed

  12. 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.

  13. Materials for Bulk Acoustic Resonators and Filters

    NASA Astrophysics Data System (ADS)

    Loebl, Hans-Peter

    2003-03-01

    Highly selective solidly mounted bulk acoustic wave (BAW) band pass filters are suited for mobile and wireless systems in the GHz frequency range between 0.8 and 10 GHz. Electro-acoustic thin film BAW resonators are the building blocks these BAW filters. Piezoelectric materials used in these resonators include mainly AlN or ZnO which can be deposited by dedicated thin film sputter deposition techniques. Using these piezo-electric materials and using suited materials for the acoustic Bragg reflector, BAW resonators with high quality factors can be fabricated. The achievable filter bandwidth is approximately 4Alternatively, also ferroelectric thin films might be used to achieve higher coupling coefficient and thus filter bandwidth. BAW resonators and filters have been designed and fabricated on 6" Silicon and glass wafers. Results are presented for resonators and filters operating between 1.95 and 8 GHz. The talk will give an overview of the material aspects which are important for BAW devices. It will be shown that modeling of the resonator and filter response using 1D electro-acoustic simulation (1,2) which includes losses is essential to extract acoustic and electrical material parameters. (1) Solidly Mounted Bulk Acoustic Wave Filters for the Ghz Frequency Range, H.P. Loebl, C. Metzmacher , D.N.Peligrad , R. Mauczok , M. Klee , W. Brand , R.F. Milsom , P.Lok , F.van Straten , A. Tuinhout , J.W.Lobeek, IEEE 2002 Ultrasonics Symposium Munich, October 2002. (2) Combined Acoustic-Electromagnetic Simulation Of Thin-Film Bulk Acoustic Wave Filters, R.F. Milsom, H-P. Löbl, D.N. Peligrad, J-W. Lobeek, A. Tuinhout, R. H. ten Dolle IEEE 2002 Ultrasonics Symposium Munich, October 2002.

  14. 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

  15. 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.

  16. Resonator decoupling and polarization of radiation in a CO 2 laser

    Microsoft Academic Search

    V. A. Zhdanovskii; V. N. Snopko

    1974-01-01

    The presence of an aperture in the mirror destroys mirror symmetry, introduces strong inhomogeneity into the spatial distribution of the radiation field, reduces laser stability, and does not ensure extraction of radiation energy from the entire transverse cross section of the active medium. In [2] the extraction of generation energy from the resonator was accomplished by means of Fresnel reflection

  17. Tunable multiwalled nanotube resonator

    DOEpatents

    Zettl, Alex K. (Kensington, CA); Jensen, Kenneth J. (Berkeley, CA); Girit, Caglar (Albany, CA); Mickelson, William E. (San Francisco, CA); Grossman, Jeffrey C. (Berkeley, CA)

    2011-03-29

    A tunable nanoscale resonator has potential applications in precise mass, force, position, and frequency measurement. One embodiment of this device consists of a specially prepared multiwalled carbon nanotube (MWNT) suspended between a metal electrode and a mobile, piezoelectrically controlled contact. By harnessing a unique telescoping ability of MWNTs, one may controllably slide an inner nanotube core from its outer nanotube casing, effectively changing its length and thereby changing the tuning of its resonance frequency. Resonant energy transfer may be used with a nanoresonator to detect molecules at a specific target oscillation frequency, without the use of a chemical label, to provide label-free chemical species detection.

  18. Tunable multiwalled nanotube resonator

    DOEpatents

    Jensen, Kenneth J; Girit, Caglar O; Mickelson, William E; Zettl, Alexander K; Grossman, Jeffrey C

    2013-11-05

    A tunable nanoscale resonator has potential applications in precise mass, force, position, and frequency measurement. One embodiment of this device consists of a specially prepared multiwalled carbon nanotube (MWNT) suspended between a metal electrode and a mobile, piezoelectrically controlled contact. By harnessing a unique telescoping ability of MWNTs, one may controllably slide an inner nanotube core from its outer nanotube casing, effectively changing its length and thereby changing the tuning of its resonance frequency. Resonant energy transfer may be used with a nanoresonator to detect molecules at a specific target oscillation frequency, without the use of a chemical label, to provide label-free chemical species detection.

  19. Ferromagnetic resonance in ?-Co magnetic composites.

    PubMed

    Chalapat, Khattiya; Timonen, Jaakko V I; Huuppola, Maija; Koponen, Lari; Johans, Christoffer; Ras, Robin H A; Ikkala, Olli; Oksanen, Markku A; Seppälä, Eira; Paraoanu, G S

    2014-12-01

    We investigate the electromagnetic properties of assemblies of nanoscale ?-cobalt crystals with size range between 5 to 35 nm, embedded in a polystyrene matrix, at microwave (1-12 GHz) frequencies. We investigate the samples by transmission electron microscopy imaging, demonstrating that the particles aggregate and form chains and clusters. By using a broadband coaxial-line method, we extract the magnetic permeability in the frequency range from 1 to 12 GHz, and we study the shift of the ferromagnetic resonance (FMR) with respect to an externally applied magnetic field. We find that the zero-magnetic field ferromagnetic resonant peak shifts towards higher frequencies at finite magnetic fields, and the magnitude of complex permeability is reduced. At fields larger than 2.5 kOe the resonant frequency changes linearly with the applied magnetic field, demonstrating the transition to a state in which the nanoparticles become dynamically decoupled. In this regime, the particles inside clusters can be treated as non-interacting, and the peak position can be predicted from Kittel's FMR theory for non-interacting uniaxial spherical particles combined with the Landau-Lifshitz-Gilbert equation. In contrast, at low magnetic fields this magnetic order breaks down and the resonant frequency in zero magnetic field reaches a saturation value reflecting the interparticle interactions as resulting from aggregation. Our results show that the electromagnetic properties of these composite materials can be tuned by external magnetic fields and by changes in the aggregation structure. PMID:25397945

  20. Ferromagnetic resonance in ?-Co magnetic composites

    NASA Astrophysics Data System (ADS)

    Chalapat, Khattiya; Timonen, Jaakko V. I.; Huuppola, Maija; Koponen, Lari; Johans, Christoffer; Ras, Robin H. A.; Ikkala, Olli; Oksanen, Markku A.; Seppälä, Eira; Paraoanu, G. S.

    2014-12-01

    We investigate the electromagnetic properties of assemblies of nanoscale ?-cobalt crystals with size range between 5 to 35 nm, embedded in a polystyrene matrix, at microwave (1–12 GHz) frequencies. We investigate the samples by transmission electron microscopy imaging, demonstrating that the particles aggregate and form chains and clusters. By using a broadband coaxial-line method, we extract the magnetic permeability in the frequency range from 1 to 12 GHz, and we study the shift of the ferromagnetic resonance (FMR) with respect to an externally applied magnetic field. We find that the zero-magnetic field ferromagnetic resonant peak shifts towards higher frequencies at finite magnetic fields, and the magnitude of complex permeability is reduced. At fields larger than 2.5 kOe the resonant frequency changes linearly with the applied magnetic field, demonstrating the transition to a state in which the nanoparticles become dynamically decoupled. In this regime, the particles inside clusters can be treated as non-interacting, and the peak position can be predicted from Kittel?s FMR theory for non-interacting uniaxial spherical particles combined with the Landau–Lifshitz–Gilbert equation. In contrast, at low magnetic fields this magnetic order breaks down and the resonant frequency in zero magnetic field reaches a saturation value reflecting the interparticle interactions as resulting from aggregation. Our results show that the electromagnetic properties of these composite materials can be tuned by external magnetic fields and by changes in the aggregation structure.

  1. Hunting resonance poles with Rational Approximants

    E-print Network

    Pere Masjuan

    2010-12-13

    Based on the mathematically well defined Pad\\'e Theory, a theoretically safe new procedure for the extraction of the pole mass and width of resonances is proposed. In particular, thanks to the Montessus de Ballore's theorem we are able to unfold the Second Riemann sheet of an amplitude to search the position of the resonant pole in the complex plane. The method is systematic and provides a model-independent treatment of the prediction and the corresponding errors of the approximation. This letter partially covers the material presented by the author at the 15th International QCD Conference: QCD 10 (25th anniversary), Montpellier, France, 28 Jun - 3 Jul 2010 and at the Quark Confinement and the Hadron Spectrum IX, 30 August - 3 September 2010, Madrid, Spain.

  2. 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.

  3. 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.

  4. Magnetic Resonance Imaging and Magnetic Resonance Spectroscopy in Dementias

    Microsoft Academic Search

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

    2001-01-01

    This article reviews recent studies of magnetic resonance imaging and magnetic resonance spectroscopy in demen tia, 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 spec troscopy can detect structural alteration and biochemical abnormalities in the brain of demented subjects and may help in the differential

  5. 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

  6. 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.

  7. Onion DNA Extraction

    NSDL National Science Digital Library

    Lana Hays

    2009-01-01

    This laboratory exercise is designed to show learners how DNA can easily be extracted from onion cells using simple materials. Use this experiment to supplement any unit on genetics and to demonstrate how scientists study DNA. Adult supervision is recommended. This resource guide includes tips and suggestions for instructors as well as other DNA extraction experiments and a chart for learners to answer questions.

  8. Yeast DNA Extraction

    NSDL National Science Digital Library

    Lana Hays

    2009-01-01

    This laboratory exercise is designed to show learners how DNA can easily be extracted from yeast using simple materials. Use this experiment to supplement any unit on genetics and to demonstrate how scientists study DNA. Adult supervision is recommended. This resource guide includes tips and suggestions for instructors as well as other DNA extraction experiments and a chart for learners to answer questions.

  9. Wheat Germ DNA Extraction

    NSDL National Science Digital Library

    Lana Hays

    2009-01-01

    This laboratory exercise is designed to show learners how DNA can easily be extracted from wheat germ using simple materials. Use this experiment to supplement any unit on genetics and to demonstrate how scientists study DNA. Adult supervision is recommended. This resource guide includes tips and suggestions for instructors as well as other DNA extraction experiments and a chart for learners to answer questions.

  10. Resonant ultrasound spectroscopy

    SciTech Connect

    Migliori, A.

    1991-11-05

    This patent describes a resonant ultrasound spectroscopy method which 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 through 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.

  11. Micro-machined resonator

    DOEpatents

    Godshall, Ned A. (Albuquerque, NM); Koehler, Dale R. (Albuquerque, NM); Liang, Alan Y. (Albuquerque, NM); Smith, Bradley K. (Albuquerque, NM)

    1993-01-01

    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.

  12. 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.

  13. 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.

  14. 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.

  15. Chemical resonant sensors

    NASA Astrophysics Data System (ADS)

    Hauptmann, Peter R.

    1993-03-01

    Resonant sensors designed to have a mechanical resonance frequency are a subject of special practical interest. They are sensors with outputs based on a quasi-digital frequency signal which is a great advantage over conventional analog sensors. Micromachined mechanical resonant sensors can be used to replace conventional piezoresistors in precision sensor applications such as pressure sensors and accelerometers. For the detecting of chemical species, only a part of known resonant sensor principles can be used for practical aims. Ultrasonic sensors can be classified in this category. They include BAW-, SAW-, APM-, and FPW-sensors. The theoretical concepts for their behavior and the advantages and disadvantages in comparison with other chemical sensors are discussed. Experimental results with BAW-sensors for gas and under-liquid sensing are given. Finally, the actual situation in research and industrial application of this sensor class is reviewed.

  16. Validating resonance properties using nuclear resonance fluorescence

    NASA Astrophysics Data System (ADS)

    Angell, C. T.; Hajima, R.; Hayakawa, T.; Shizuma, T.; Karwowski, H. J.; Silano, J.

    2014-11-01

    Measurement of a resonance's integrated cross section using nuclear resonance fluorescence can be a valuable tool for verifying the properties of the resonance because of the clear and unambiguous physical connection to the spin, lifetime, and ground state branching ratio of the level. We demonstrate this idea by measuring the integrated cross section of the 3.004-MeV level in 27Al to 4% using the monoenergetic ? -ray beam at the High Intensity ? -ray Source. That level was the subject of much debate experimentally in the 1960s, especially its spin, and even now only has a current tentative spin assignment of J =(9 /2 ) . The consistency check between this integrated cross section and the known properties of the level indicate that one (or more) of the literature properties is incorrect. Based on the range of extent of each property, a reassignment of spin to a tentative J =(7 /2 ) may be warranted, but this would need to be confirmed with other measurements. This result demonstrates the utility of NRF as a way to verify the properties of states in the literature before undertaking more extensive measurements.

  17. P-31 nuclear magnetic resonance analysis of brain: Normoxic and anoxic brain slices

    Microsoft Academic Search

    Maynard M. Cohen; Jay W. Pettegrew; Stephen J. Kopp; Nancy Minshew; Thomas Glonek

    1984-01-01

    Perchloric acid extracts were prepared from liquid-N2-frozen gerbil and guinea pig brain slices studied under one of three conditions: O2-incubated, N2-incubated or O2-incubated recovery following N2 incubation. Mole percentages of the various phosphatic components contained in the extracts were determined by phosphorus-31 nuclear magnetic resonance spectroscopy. The brain slice extract spectrum revealed a previously unreported group of brain phosphodiesters at

  18. Infrared Dielectric Resonator Metamaterial

    E-print Network

    Ginn, James C; Peters, David W; Wendt, Joel R; Stevens, Jeffrey O; Hines, Paul F; Basilio, Lorena I; Warne, Larry K; Ihlefeld, Jon F; Clem, Paul G; Sinclair, Michael B

    2011-01-01

    We demonstrate, for the first time, an all-dielectric metamaterial resonator in the mid-wave infrared based on high-index tellurium cubic inclusions. Dielectric resonators are desirable compared to conventional metallo-dielectric metamaterials at optical frequencies as they are largely angular invariant, free of ohmic loss, and easily integrated into three-dimensional volumes. With these low-loss, isotropic elements, disruptive optical metamaterial designs, such as wide-angle lenses and cloaks, can be more easily realized.

  19. Cyclotron resonance and quasiparticles

    SciTech Connect

    Cohen, Marvin L.

    2005-01-15

    This introductory paper contains personal perspectives about the importance of cyclotron resonance in forming our modern view of solids. The papers following this one will discuss the discovery, refinements, and some of the latest developments. Although I will touch on some of these subjects, I leave the details to the other authors and in the main focus on the conceptual impact of the work. I propose that it was experiments based on cyclotron resonance which established the quasiparticle concept.

  20. 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.

  1. 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.

  2. Optical Feshbach Resonances: Field-Dressed Theory and Experimental Comparisons

    E-print Network

    Nicholson, T L; Bloom, B J; Williams, J R; Thomsen, J W; Ye, J; Julienne, P S

    2015-01-01

    Optical Feshbach resonances (OFRs) have generated significant experimental interest in recent years. These resonances are promising for many-body physics experiments, yet the practical application of OFRs has been limited. The theory of OFRs has been based on an approximate model that fails in important detuning regimes, and the incomplete theoretical understanding of this effect has hindered OFR experiments. We present the most complete theoretical treatment of OFRs to date, demonstrating important characteristics that must be considered in OFR experiments and comparing OFRs to the well studied case of magnetic Feshbach resonances. We also present a comprehensive treatment of the approximate OFR model, including a study of the range of validity for this model. Finally, we derive experimentally useful expressions that can be applied to real experimental data to extract important information about the resonance structure of colliding atoms.

  3. 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

  4. 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

  5. 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.

  6. Pygmy dipole resonance in 208Pb

    E-print Network

    I. Poltoratska; P. von Neumann-Cosel; A. Tamii; T. Adachi; C. A. Bertulani; J. Carter; M. Dozono; H. Fujita; K. Fujita; Y. Fujita; K. Hatanaka; M. Itoh; T. Kawabata; Y. Kalmykov; A. M. Krumbholz; E. Litvinova; H. Matsubara; K. Nakanishi; R. Neveling; H. Okamura; H. J. Ong; B. Özel-Tashenov; V. Yu. Ponomarev; A. Richter; B. Rubio; H. Sakaguchi; Y. Sakemi; Y. Sasamoto; Y. Shimbara; Y. Shimizu; F. D. Smit; T. Suzuki; Y. Tameshige; J. Wambach; M. Yosoi; J. Zenihiro

    2012-03-29

    Scattering of protons of several hundred MeV is a promising new spectroscopic tool for the study of electric dipole strength in nuclei. A case study of 208Pb shows that at very forward angles J^pi = 1- states are strongly populated via Coulomb excitation. A separation from nuclear excitation of other modes is achieved by a multipole decomposition analysis of the experimental cross sections based on theoretical angular distributions calculated within the quasiparticle-phonon model. The B(E1) transition strength distribution is extracted for excitation energies up to 9 MeV, i.e., in the region of the so-called pygmy dipole resonance (PDR). The Coulomb-nuclear interference shows sensitivity to the underlying structure of the E1 transitions, which allows for the first time an experimental extraction of the electromagnetic transition strength and the energy centroid of the PDR.

  7. Antioxidant activity of Chinese ant extract preparations.

    PubMed

    Zhao, Y; Wang, X; Kawai, M; Liu, J; Liu, M; Mori, A

    1995-12-01

    Chinese ant extract preparations (CAEP) are a Chinese traditional medicine which is mainly used as a health food or drink for the treatment of rheumatism, rheumatoid arthritis, chronic hepatitis, sexual hypofunction, and antiaging in China. The effects on free radicals were examined by electron spin resonance spectrometry using the spin trapping agent 5.5-dimethyl-1-pyrroline-1-oxide (DMPO). Superoxide radicals (3.35 x 10(15) spins/ml) were quenched 50% by the extract at 0.5 mg/ml. The CAEP extract at 0.7 mg/ml inhibited 50% of hydroxyl radicals (52.0 x 10(15) spins/ml) generated by the Fenton reaction. Against DPPH radical, the scavenging action of CAEP was observed at 1.8 mg/ml of the extract and 50% of the DPPH radicals (8.14 x 10(15) spins/ml) were quenched. In vitro tests showed that CAEP inhibited the production of thiobarbituric acid-reactive substances, an index of lipid peroxidation, in rat brain homogenate. PMID:8770235

  8. 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.

  9. Quantify Resonance Inspection with Finite Element-Based Modal Analyses

    SciTech Connect

    Sun, Xin; Lai, Canhai; Dasch, Cameron

    2010-11-10

    Resonance inspection uses the natural acoustic resonances of a part to identify anomalous parts. Modern instrumentation can measure the many resonant frequencies rapidly and accurately. Sophisticated sorting algorithms trained on sets of good and anomalous parts can rapidly and reliably inspect and sort parts. This paper aims at using finite-element-based modal analysis to put resonance inspection on a more quantitative basis. A production-level automotive steering knuckle is used as the example part for our study. First, the resonance frequency spectra for the knuckle are measured with two different experimental techniques. Next, scanning laser vibrometry is used to determine the mode shape corresponding to each resonance. The material properties including anisotropy are next measured to high accuracy using resonance spectroscopy on cuboids cut from the part. Then, finite element model (FEM) of the knuckle is generated by meshing the actual part geometry obtained with computed tomography (CT). The resonance frequencies and mode shapes are next predicted with a natural frequency extraction analysis after extensive mesh size sensitivity study. The good comparison between the predicted and the experimentally measured resonance spectra indicate that finite-element-based modal analyses have the potential to be a powerful tool in shortening the training process and improving the accuracy of the resonance inspection process for a complex, production level part. The finite element based analysis can also provide a means to computationally test the sensitivity of the frequencies to various possible defects such as porosity or oxide inclusions especially in the high stress regions that the part will experience in service.

  10. Quantify Resonance Inspection with Finite Element-Based Modal Analyses

    SciTech Connect

    Lai, Canhai; Sun, Xin; Dasch, Cameron; Harmon, George; Jones, Martin

    2011-06-01

    Resonance inspection uses the natural acoustic resonances of a part to identify anomalous parts. Modern instrumentation can measure the many resonant frequencies rapidly and accurately. Sophisticated sorting algorithms trained on sets of good and anomalous parts can rapidly and reliably inspect and sort parts. This paper aims at using finite-element-based modal analysis to put resonance inspection on a more quantitative basis. A production-level automotive steering knuckle is used as the example part for our study. First, the resonance frequency spectra for the knuckle are measured with two different experimental techniques. Next, scanning laser vibrometry is used to determine the mode shape corresponding to each resonance. The material properties including anisotropy are next measured to high accuracy using resonance spectroscopy on cuboids cut from the part. Then, finite element model (FEM) of the knuckle is generated by meshing the actual part geometry obtained with computed tomography (CT). The resonance frequencies and mode shapes are next predicted with a natural frequency extraction analysis after extensive mesh size sensitivity study. The good comparison between the predicted and the experimentally measured resonance spectra indicate that finite-element-based modal analyses have the potential to be a powerful tool in shortening the training process and improving the accuracy of the resonance inspection process for a complex, production level part. The finite element based analysis can also provide a means to computationally test the sensitivity of the frequencies to various possible defects such as porosity or oxide inclusions especially in the high stress regions that the part will experience in service.

  11. Hyperbolic Resonances of Metasurface Cavities

    E-print Network

    Keene, David

    2015-01-01

    We propose a new class of optical resonator structures featuring one or two metasurface reflectors or metacavities and predict that such resonators support novel hyperbolic resonances. As an example of such resonances we introduce hyperbolic Tamm plasmons (HTPs) and hyperbolic Fabry-Perot resonances (HFPs). The hyperbolic optical modes feature low-loss incident power re-distribution over TM and TE polarization output channels, clover-leaf anisotropic dispersion, and other unique properties which are tunable and are useful for multiple applications.

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

    NASA Astrophysics Data System (ADS)

    Yang, Juan; Shi, Feng; Jin, Yizhou; Wang, Yunmin; Komurasaki, Kimiya

    2013-12-01

    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 × 1016-4.8 × 1017 m-3, respectively.

  13. 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.

  14. MACHINERY RESONANCE AND DRILLING

    SciTech Connect

    Leishear, R.; Fowley, M.

    2010-01-23

    New developments in vibration analysis better explain machinery resonance, through an example of drill bit chattering during machining of rusted steel. The vibration of an operating drill motor was measured, the natural frequency of an attached spring was measured, and the two frequencies were compared to show that the system was resonant. For resonance to occur, one of the natural frequencies of a structural component must be excited by a cyclic force of the same frequency. In this case, the frequency of drill bit chattering due to motor rotation equaled the spring frequency (cycles per second), and the system was unstable. A soft rust coating on the steel to be drilled permitted chattering to start at the drill bit tip, and the bit oscillated on and off of the surface, which increased the wear rate of the drill bit. This resonant condition is typically referred to as a motor critical speed. The analysis presented here quantifies the vibration associated with this particular critical speed problem, using novel techniques to describe resonance.

  15. 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.

  16. Complete Bacterial Proteome Extraction Kit

    E-print Network

    Lebendiker, Mario

    ....................................................................................7 7. Extraction of proteins from gram-negative bacteria.................................................................8 8. Extraction of proteins from gram-positive bacteria by centrifugation and sample preparation with was performed. 200 µg proteins of the whole cell extract were

  17. 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...

  18. Liquid chromatographic extraction medium

    DOEpatents

    Horwitz, E.P.; Dietz, M.L.

    1994-09-13

    A method and apparatus are disclosed for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column. 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. 1 fig.

  19. DNA Extraction Virtual Lab

    NSDL National Science Digital Library

    2006-01-01

    This virtual lab from the Genetic Science Learning Center at the University of Utah provides a simple overview of DNA extraction, including what it's used for, illustrations, and an activity using cheek cells and laboratory equipment to isolate DNA. The lab is followed by a classroom activity that allows students and teachers to Extract DNA from Anything Living, using household items like spinach but not little sister's big toe.

  20. Fruitful DNA Extraction

    NSDL National Science Digital Library

    Karen Kalamuck

    2000-01-01

    In this lab activity, learners get to see and touch the genetic material they extract from the cells of a kiwi fruit - no high tech equipment required! After extraction and precipitation, learners will be able to collect the DNA with a wire hook. A facilitator's guide is included for helping educators run the activity, and background information is provided about what's going on, discussion questions, and ideas for inquiry. Biochemistry has never been so accessible - and fun!

  1. Thymus DNA Extractions

    NSDL National Science Digital Library

    Lana Hays

    2009-01-01

    This laboratory exercise is designed to show learners how DNA can be extracted from a chunk of thymus (sweetbread) or liver. This experiment requires the use of a centrifuge (not included in cost of materials). Use this experiment to supplement any unit on genetics and to demonstrate how scientists study DNA. Adult supervision is recommended. This resource guide includes tips and suggestions for instructors as well as other DNA extraction experiments and a chart for learners to answer questions.

  2. 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.

  3. Coupled Fano resonators.

    PubMed

    Tu, Xiaoguang; Mario, Landobasa Y; Mei, Ting

    2010-08-30

    We theoretically investigate coupled Fano structures which combine the characteristics of both directly coupled Fabry-Perot cavities (DCFPC) and a side-coupled integrated spaced sequence of resonators (SCISSOR). Asymmetric and symmetric Fano resonances in a single and doubly-coupled Fano unit are analytically derived based on Fabry-Perot approach. It is found that doubly-coupled Fano units show a special asymmetric EIT-like lineshape. This structure shows an index changing sensitivity of 10(-6), about two orders higher than that of the single Fano resonator, which is promising for index sensor application. A unique frequency detuning method of EIT like lineshape is also found in the doubly-coupled Fano units. The multiple coupled Fano unit structure demonstrates potentials for applications of tunable optical filter and slow light, whereas for the latter it shows much higher group delay than that of SCISSORS and DCFPC with the same parameters. PMID:20940775

  4. Resonances and inverse scattering

    NASA Astrophysics Data System (ADS)

    Bledsoe, Matthew B.

    Inverse scattering problems for Sturm-Liouville differential equations find numerous applications in physics, in particular, quantum mechanics. While the theory of these problems has been developed over a number of decades, a more recent concern has been the use of resonances, important phenomena in physics, as data---the inverse resonance problem. In this dissertation, we address this problem in a variety of cases. First, we investigate the full-line Schrodinger equation where the data for the inverse problem include the eigenvalues and resonances. We prove that any two potentials that have enough data points sufficiently close together must also be close in a suitable sense. We then prove a discrete analogue for a full-line Jacobi equation. Finally, we prove a uniqueness theorem for a left-definite, half-line Sturm-Liouville equation. Along the way, we improve upon the current inverse spectral and scattering theorems for this equation.

  5. 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.

  6. 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.

  7. 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.

  8. Extraction processes for bioproduct separation

    SciTech Connect

    Hartl, J.; Marr, R. [Technische Universitaet Graz (Austria)

    1993-01-01

    The three-phase extraction process, a modification of reactive extraction, was investigated for its applicability in the separation of organic acids from fermentation broth. It was compared with reactive extraction, liquid membrane permeation, and supercritical fluid extraction. These processes are based on the use of amine extractants, which have to be dissolved in nonpolar solvents, for the extraction of carboxylic acids, hydroxycarboxylic acids, and aminocarboxylic acids. This paper considers the comparison of the above-mentioned processes. Furthermore, the extractability of acids from synthetic aqueous solutions and fermented broths was compared. Principal consideration was paid to the extraction of lactic acid, gluconic acid, citric acid, and L-leucine.

  9. The {Delta}(1232) resonance transition form factor

    SciTech Connect

    Staurt, L.M. [California Univ., Davis, CA (United States)]|[Lawrence Livermore National Lab., CA (United States); Bosted, P.E.; Lung, A. [The American Univ., Washington, DC (United States)] [and others

    1993-08-01

    Old and new measurements of inclusive e--p cross sections in the {Delta}(1232) resonance region have been combined, and a global data fit has been made. Using this fit to parameterize the nonresonant background, the transition form factors have been extracted out to a four-momentum transfer, Q{sup 2}, of 9.8 (GeV/c){sup 2}. The results are systematically higher than those from a previous analysis, but agree within errors. A similar analysis has been done with e--d cross sections, and {sigma}{sub n}/{sigma}{sub p} in the {Delta}(1232) resonance region has been extracted out to a Q{sup 2} of 7.9 (GeV/c){sup 2}. {sigma}{sub n}/{sigma}{sub p} for {Delta}(1232) production is consistent with unity, while {sigma}{sub n}/{sigma}{sub p} for the nonresonant background is constant with Q{sup 2} at approximately 0.4.

  10. 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

  11. 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.

  12. Physics of Sports: Resonances

    NASA Astrophysics Data System (ADS)

    Browning, David

    2000-04-01

    When force is applied by an athlete to sports equipment resonances can occur. Just a few examples are: the ringing of a spiked volleyball, the strumming of a golf club shaft during a swing, and multiple modes induced in an aluminum baseball bat when striking a ball. Resonances produce acoustic waves which, if conditions are favorable, can be detected off the playing field. This can provide a means to evaluate athletic performance during game conditions. Results are given from the use of a simple hand-held acoustic detector - by a spectator sitting in the stands - to determine how hard volleyballs were spiked during college and high school games.

  13. 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.

  14. Field resonance propulsion concept

    NASA Technical Reports Server (NTRS)

    Holt, A. C.

    1979-01-01

    A propulsion concept was developed based on a proposed resonance between coherent, pulsed electromagnetic wave forms, and gravitational wave forms (or space-time metrics). Using this concept a spacecraft propulsion system potentially capable of galactic and intergalactic travel without prohibitive travel times was designed. The propulsion system utilizes recent research associated with magnetic field line merging, hydromagnetic wave effects, free-electron lasers, laser generation of megagauss fields, and special structural and containment metals. The research required to determine potential, field resonance characteristics and to evaluate various aspects of the spacecraft propulsion design is described.

  15. Pygmy resonances and nucleosynthesis

    E-print Network

    Nadia Tsoneva; Horst Lenske

    2014-11-14

    A microscopic theoretical approach based on a self-consistent density functional theory for the nuclear ground state and QRPA formalism extended with multi-phonon degrees of freedom for the nuclear excited states is implemented in investigations of new low-energy modes called pygmy resonances. Advantage of the method is the unified description of low-energy multiphonon excitations, pygmy resonances and core polarization effects. This is found of crucial importance for the understanding of the fine structure of nuclear response functions at low energies. Aspects of the precise knowledge of nuclear response functions around the neutron threshold are discussed in a connection to nucleosynthesis.

  16. Electromagnetic excitation of the Delta(1232) resonance

    SciTech Connect

    V. Pascalutsa; M. Vanderhaeghen; Shin Nan Yang

    2006-09-05

    We review the description of the lowest-energy nucleon excitation--the Delta(1232)-resonance. Much of the recent effort has been focused on the precision measurements of the nucleon to Delta transition by means of electromagnetic probes. We review the results of those measurements and confront them with the state-of-the-art calculations based on chiral effective-field theories (EFT), lattice QCD, and QCD-inspired models. Some of the theoretical approaches are reviewed in detail. In particular, we describe the chiral EFT of QCD in the energy domain of the Delta-resonance, and its applications to the electromagnetic nucleon-to-Delta transition (gamma N Delta). We also describe the recent dynamical and unitary-isobar models of pion electroproduction which are extensively used in the extraction of the gamma* N Delta form factors from experiment. Furthermore, we discuss the link of the gamma* N Delta form factors to generalized parton distributions (GPDs), as well as the predictions of perturbative QCD for these transition form factors. The present status of understanding the Delta-resonance properties and the nature of its excitation is summarized.

  17. Continuous-wave intra-cavity singly resonant optical parametric oscillator with resonant wave output coupling.

    PubMed

    Sheng, Quan; Ding, Xin; Shang, Ce; Li, Bin; Fan, Chen; Zhang, Haiyong; Yu, Xuanyi; Wen, Wuqi; Ma, Yila; Yao, Jianquan

    2012-12-01

    We report herein the enhancement in both power and efficiency performance of a continuous-wave intra-cavity singly resonant optical parametric oscillator (ICSRO) by introducing finite resonant wave output coupling. While coupling out the resonant wave to useful output, the output coupling increases the SRO threshold properly thus suppresses the back-conversion under high pump power. Therefore, the down-conversion efficiency is maintained under high pump without having to raise the threshold by defocusing. With a T = 9.6% signal wave output coupler used, the SRO threshold is 2.46 W and the down-conversion efficiency is 72.9% under the maximum pump power of 21.4 W. 1.43 W idler power at 3.66 ?m and 5.03 W signal power at 1.5 ?m are obtained, corresponding to a total extraction efficiency of 30.2%. The resonant wave out coupling significantly levels up the upper limit for the power range where the ICSRO exhibits high efficiency, without impeding its advantage of low threshold. PMID:23262741

  18. 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.

  19. 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

  20. Appl. Magn. Reson. 28, 1XXX (2005) Magnetic Resonance

    E-print Network

    Baker, Chris I.

    Appl. Magn. Reson. 28, 1XXX (2005) Applied Magnetic Resonance © Springer-Verlag 2005 Printed-based functional magnetic resonance imaging (fMRI) techniques have proven to be extremely robust and sensitive firing spatially and temporally integrates on the spatial scale of an MRI voxel to produce a magnetic

  1. High-Q bandpass resonators utilizing bandstop resonator pairs

    NASA Technical Reports Server (NTRS)

    Okean, H. C. (inventor)

    1973-01-01

    A high-Q bandpass resonators utilizing composite bandstop resonator pairs is reported. The bandstop resonator pairs are formed of composite series or parallel connected realizable transmission line elements. The elements are exclusively either quarter-wavelength lines or half-wavelength lines.

  2. 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)

  3. Width of nonlinear resonance

    SciTech Connect

    Ohnuma, S.

    1984-03-01

    Two approximations are made, one essential and the other not so essential but convenient to keep the analytical treatment manageable: (1) Only one nonlinear resonance is considered at a time so that the treatment is best suited when the tune is close to one resonance only. To improve this approximation, one must go to the next order which involves a canonical transformation of dynamical variables. Analytical treatment of more than one resonance is not possible for general cases. (2) In the formalism using the action-angle variables, the Hamiltonian can have terms which are independent of the angle variables. These terms are called phase-independent terms or shear terms. The tune is then a function of the oscillation amplitudes. In the lowest-order treatment, the (4N)-pole components but not the (4N + 2)-pole components contribute to this dependence. In deriving the resonance width analytically, one ignores these terms in the Hamiltonian for the sake of simplicity. If these are retained, one needs at least three extra parameters and the analytical treatment becomes rather unwieldy.

  4. 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.

  5. Magnetic Resonance Imaging

    NSDL National Science Digital Library

    2014-09-18

    This lesson ties the preceding lessons together and brings students back to the grand challenge question on MRI safety. During this lesson, students focus on the logistics of magnetic resonance imaging as well as the MRI hardware. Students can then integrate this knowledge with their acquired knowledge on magnetic fields to solve the challenge question.

  6. Clinical magnetic resonance imaging

    SciTech Connect

    Brady, T.J.; Edelman, R.R.

    1988-01-01

    This book presents clinical applications of magnetic resonance imaging with a strong clinical orientation. Covers technique, instrumentation, and contrast agents. Describes MRI of the neck, brain, heart, spine, TMJ and orbit, chest abdomen, pelvis, and the joints. Also includes a high field atlas of the central nervous system.

  7. Nuclear magnetic resonance imaging

    SciTech Connect

    Young, I.R.

    1984-07-03

    A method of imaging a body by nuclear magnetic resonance wherein volume scanning of a region of the body is achieved by scanning a first planar slice of the region and at least one further slice of the region in the relaxation time for the scan of the first slice.

  8. Resonance tube igniter

    NASA Technical Reports Server (NTRS)

    Conrad, E. W.; Pavli, A. J.; Phillips, B. R.

    1970-01-01

    Reasonance induced in stoichiometric mixtures of gaseous hydrogen-oxygen produces temperatures /over 1100 deg F/ high enough to cause ignition. Resonance tube phenomenon occurs when high pressure gas is forced through sonic or supersonic nozzle into short cavity. Various applications for the phenomenon are discussed.

  9. 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.

  10. Laser beams and resonators

    Microsoft Academic Search

    H. Kogelnik; T. Li

    1966-01-01

    This paper is a review of the theory of laser beams and resonators. It is meant to be tutorial in nature and useful in scope. No attempt is made to be exhaustive in the treatment. Rather, emphasis is placed on formulations and derivations which lead to basic understanding and on results which bear practical significance.

  11. Resonant scanning mechanism

    NASA Astrophysics Data System (ADS)

    Wallace, John; Newman, Mike; Gutierrez, Homero; Hoffman, Charlie; Quakenbush, Tim; Waldeck, Dan; Leone, Christopher; Ostaszewski, Miro

    2014-10-01

    Ball Aerospace & Technologies Corp. developed a Resonant Scanning Mechanism (RSM) capable of combining a 250- Hz resonant scan about one axis with a two-hertz triangular scan about the orthogonal axis. The RSM enables a rapid, high-density scan over a significant field of regard (FOR) while minimizing size, weight, and power requirements. The azimuth scan axis is bearing mounted allowing for 30° of mechanical travel, while the resonant elevation axis is flexure and spring mounted with five degrees of mechanical travel. Pointing-knowledge error during quiescent static pointing at room temperature across the full range is better than 100 ?rad RMS per axis. The compact design of the RSM, roughly the size of a soda can, makes it an ideal mechanism for use on low-altitude aircraft and unmanned aerial vehicles. Unique aspects of the opto-mechanical design include i) resonant springs which allow for a high-frequency scan axis with low power consumption; and ii) an independent lower-frequency scan axis allowing for a wide FOR. The pointing control system operates each axis independently and employs i) a position loop for the azimuth axis; and ii) a unique combination of parallel frequency and amplitude control loops for the elevation axis. All control and pointing algorithms are hosted on a 200-MHz microcontroller with 516 KB of RAM on a compact 3"×4" digital controller, also of Ball design.

  12. Functional Magnetic Resonance Imaging

    ERIC Educational Resources Information Center

    Voos, Avery; Pelphrey, Kevin

    2013-01-01

    Functional magnetic resonance imaging (fMRI), with its excellent spatial resolution and ability to visualize networks of neuroanatomical structures involved in complex information processing, has become the dominant technique for the study of brain function and its development. The accessibility of in-vivo pediatric brain-imaging techniques…

  13. 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.

  14. Acoustic meta-materials in MEMS BAW resonators

    NASA Astrophysics Data System (ADS)

    Rottenberg, X.; Jansen, R.; Van Hoof, C.; Tilmans, H. A. C.

    2011-06-01

    This paper presents a meta-material-based design method for bulk acoustic wave (BAW) resonators with enhanced characteristics compared to those obtained with the typical bulk material implementation. We demonstrate the novel use of empty inclusions (i.e., `holes') in bulk materials for engineering their acoustic (mechanical) properties (e.g. Young's modulus E, Poisson's ratio ? and mass density ?) to tune and achieve optimal acoustical performance/characteristics. Inclusions have been demonstrated before to produce phononic band gaps for wave trapping. We focus on the propagation characteristics of the meta-materials brought into being by these inclusions. We implement patterns of holes with different sizes and distributions, to effectively scatter acoustic waves in bar-type BAW resonators and to devise the desired resonator properties, e.g., the resonant frequency. While the available bulk material is homogeneous and isotropic, the bar consists of an equivalent non-homogeneous material that can for example be distributed by design in order to shrink the overall resonator size, enhance electromechanical transduction coefficients or reject spurious modes. Our paper compares two extraction methods for the equivalent material properties of a periodically hole-punched material: the steady-state mechanical simulation of a unit cell and its `phase delay' counterpart. We discuss their validity and practical use for the design of bar resonators.

  15. A Macroscopic Mechanical Resonator Operated in the Quantum Limit

    NASA Astrophysics Data System (ADS)

    O'Connell, Aaron D.

    We report the experimental results of a superconducting quantum bit coupled to a macroscopic mechanical resonator. The coupled sample was cooled in a dilution refrigerator to T = 25 mK. At this temperature, we measured the phonon occupation of the mechanical resonator and found it to be in the quantum ground state with high probability P 0 > 93%. We then excited the mechanical resonator from its ground state |0> to the single phonon state |1> by transferring a single quantum excitation from the quantum bit to the mechanical resonator. Using this ability, we probed the energy lifetime of the mechanical resonator, T1M = 6.1 ns, by monitoring the decay of a single phonon state. Next, we measured the decay of the superposed phonon state (|0>+|1>)/ 2 in order to extract the phase coherence time T 2M ? 2T1M. Finally, we explored higher phonon energy levels by directly exciting the mechanical resonator with a classical microwave source, thus creating a mechanical coherent state.

  16. 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.

  17. 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

  18. Magnetic Resonance Facility (Fact Sheet)

    SciTech Connect

    Not Available

    2012-03-01

    This fact sheet provides information about Magnetic Resonance Facility capabilities and applications at NREL's National Bioenergy Center. Liquid and solid-state analysis capability for a variety of biomass, photovoltaic, and materials characterization applications across NREL. NREL scientists analyze solid and liquid samples on three nuclear magnetic resonance (NMR) spectrometers as well as an electron paramagnetic resonance (EPR) spectrometer.

  19. Introduction Magnetic Resonance Imaging (MRI)

    E-print Network

    Wirosoetisno, Djoko

    Introduction Statistics Magnetic Resonance Imaging (MRI) Statistics in the UK Statistics at UCL and Beyond #12;Introduction Statistics Magnetic Resonance Imaging (MRI) Statistics in the UK Statistics Magnetic Resonance Imaging (MRI) Statistics in the UK Statistics at UCL Outline Why do Statistics? Some

  20. 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.

  1. Repetitive resonant railgun power supply

    DOEpatents

    Honig, Emanuel M. (Los Alamos, NM); Nunnally, William C. (Los Alamos, NM)

    1988-01-01

    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.

  2. Resonant cavity enhanced photonic devices

    Microsoft Academic Search

    M. Selim Ünlü; Samuel Strite

    1995-01-01

    We review the family of optoelectronic devices whose performance is enhanced by placing the active device structure inside a Fabry-Perot resonant microcavity. Such resonant cavity enhanced (RCE) devices benefit from the wavelength selectivity and the large increase of the resonant optical field introduced by the cavity. The increased optical field allows RCE photodetector structures to be thinner and therefore faster,

  3. Resonant Quadrupole Peter Cameron -BNL

    E-print Network

    Large Hadron Collider Program

    Resonant Quadrupole Monitor Peter Cameron - BNL #12;LARP Workshop at FNAL6/9/2003 2 Resonant BPM · Resonate above coherent spectrum #12;LARP Workshop at FNAL6/9/2003 3 Basic Method - Quadrupole Oscillations, Quadrupole BTF possible with this system. #12;LARP Workshop at FNAL6/9/2003 4 Dynamic Range Problem · Dynamic

  4. 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.

  5. Super-Gaussian reflectivity unstable resonator for excimer lasers

    Microsoft Academic Search

    M. R. Perrone; F. Mezzolla; C. Cali; C. Pace

    1991-01-01

    High-mode-volume, good optical quality laser beams of 55 mJ, of 19 ns duration and with a brightness of 3 x 10 to the 13th W\\/sq cm Sr, have been extracted from a high-gain, short-pulse XeCl laser, with an unstable resonator using a super-Gaussian reflectivity mirror. The misalignment angle of the output coupler to decrease the normalized output energy by 20

  6. Resonant characteristics of ultranarrow SiCN nanomechanical resonators

    NASA Astrophysics Data System (ADS)

    Guthy, Csaba; Das, Rahul M.; Drobot, Brian; Evoy, Stephane

    2010-07-01

    We report the machining of doubly-clamped SiCN nanomechanical resonators as narrow as 16 nm and lengths of up to 10 ?m with a yield approaching 100%. The resonators were actuated using a piezoelectric disk, and their resonant response was detected using optical interferometry. Resonators with widths ranging from 16 to 375 nm and lengths from 10 to 50 ?m were analyzed at room temperature at pressures ranging from 10 to 50 mTorr. Resonant frequencies in the 4-15 MHz range and quality factors in the 1000-7000 range were measured. We observed a significant decrease in resonant frequency with decreasing resonator width. The results of finite element analysis (FEA) show that this width dependence is mainly due to the resonators vibrating in the horizontal rather than vertical direction. At widths below 50 nm the comparison of experimental and FEA data suggest a gradual tensile stress reduction in the resonators as their width is reduced. Material softening is the most likely cause of this stress reduction. Additionally, the resonant behavior of 16, 55, and 375 nm wide devices was studied as a function of ambient pressure in the 10-5-10 Torr range. Resonance quality becomes dominated by gas damping effects at pressures above a threshold determined by the intrinsic Q-factor of the resonator. The intrinsic Q-factor tended to decrease with decreasing resonator width but was independent of length or resonant frequency. This suggests that surface-related mechanisms dominate the dissipation of energy in these devices.

  7. Wideband energy harvesting for piezoelectric devices with linear resonant behavior.

    PubMed

    Luo, Cheng; Hofmann, Heath F

    2011-07-01

    In this paper, an active energy harvesting technique for a spring-mass-damper mechanical resonator with piezoelectric electromechanical coupling is investigated. This technique applies a square-wave voltage to the terminals of the device at the same frequency as the mechanical excitation. By controlling the magnitude and phase angle of this voltage, an effective impedance matching can be achieved which maximizes the amount of power extracted from the device. Theoretically, the harvested power can be the maximum possible value, even at off-resonance frequencies. However, in actual implementation, the efficiency of the power electronic circuit limits the amount of power harvested. A power electronic full-bridge converter is built to implement the technique. Experimental results show that the active technique can increase the effective bandwidth by a factor of more than 2, and harvests significantly higher power than rectifier-based circuits at off-resonance frequencies. PMID:21768014

  8. Damping of metallized bilayer nanomechanical resonators at room temperature

    NASA Astrophysics Data System (ADS)

    Seitner, Maximilian J.; Gajo, Katrin; Weig, Eva M.

    2014-11-01

    We investigate the influence of gold thin-films subsequently deposited on a set of initially bare, doubly clamped, high-stress silicon nitride string resonators at room temperature. Analytical expressions for resonance frequency, quality factor and damping for both in- and out-of-plane flexural modes of the bilayer system are presented, which allows for the determination of effective elastic parameters of the composite structure from our experimental data. We find the inverse quality factor to scale linearly with the gold film thickness, indicating that the overall damping is governed by losses in the metal. Correspondingly, the mechanical linewidth increases by more than one order of magnitude compared to the bare silicon nitride string resonator. Furthermore, we extract mechanical quality factors of the gold film for both flexural modes and show that they can be enhanced by complete deposition of the metal in a single step, suggesting that surface and interface losses play a vital role in metal thin-films.

  9. 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.

  10. Quartz crystal microbalance based on torsional piezoelectric resonators

    SciTech Connect

    Buecking, W.; Du, B.; Turshatov, A.; Koenig, A. M.; Reviakine, I.; Bode, B.; Johannsmann, D. [Institute of Physical Chemistry, Clausthal University of Technology, Arnold-Sommerfeld-Strasse 4, D-38678 Clausthal-Zellerfeld (Germany); Flucon Fluid Control GmbH, Burgstaetter Strasse 6, D-38678 Clausthal-Zellerfeld (Germany); Institute of Physical Chemistry, Clausthal University of Technology, Arnold-Sommerfeld-Strasse 4, D-38678 Clausthal-Zellerfeld (Germany)

    2007-07-15

    A quartz crystal microbalance (QCM) is described, which is based on a torsional resonator, rather than a conventional thickness-shear resonator. Typical applications are measurements of film thickness in the coating industry and monitoring of biofouling. The torsional QCM is about a factor of 100 less sensitive than the conventional QCM. On the other hand, it can probe film thicknesses in the range of hundreds of microns, which is impossible with the conventional QCM due to viscoelastic artifacts. Data acquisition and data analysis proceed in analogy to the conventional QCM. An indicator of the material's softness can be extracted from the bandwidth of the resonance. Within the small-load approximation, the frequency shift is independent of whether the sample is applied to the face or to the side of the cylinder. Details of the geometry matter if the viscoelastic properties of the sample are of interest.

  11. Ferromagnetic resonance in $\\epsilon$-Co magnetic composites

    E-print Network

    Chalapat, Khattiya; Huuppola, Maija; Koponen, Lari; Johans, Christoffer; Ras, Robin H A; Ikkala, Olli; Oksanen, Markku A; Seppälä, Eira; Paraoanu, G S

    2014-01-01

    We investigate the electromagnetic properties of assemblies of nanoscale $\\epsilon$-cobalt crystals with size range between 5 nm to 35 nm, embedded in a polystyrene (PS) matrix, at microwave (1-12 GHz) frequencies. We investigate the samples by transmission electron microscopy (TEM) imaging, demonstrating that the particles aggregate and form chains and clusters. By using a broadband coaxial-line method, we extract the magnetic permeability in the frequency range from 1 to 12 GHz, and we study the shift of the ferromagnetic resonance with respect to an externally applied magnetic field. We find that the zero-magnetic field ferromagnetic resonant peak shifts towards higher frequencies at finite magnetic fields, and the magnitude of complex permeability is reduced. At fields larger than 2.5 kOe the resonant frequency changes linearly with the applied magnetic field, demonstrating the transition to a state in which the nanoparticles become dynamically decoupled. In this regime, the particles inside clusters can ...

  12. Surface-resistance measurements using superconducting stripline resonators

    NASA Astrophysics Data System (ADS)

    Hafner, Daniel; Dressel, Martin; Scheffler, Marc

    2014-01-01

    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.

  13. 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

  14. Ohmic effects in quasioptical resonators

    SciTech Connect

    Hargreaves, T.A.; Fischer, R.P.; McCowan, R.B.; Fliflet, A.W. (Naval Research Lab., Washington, DC (United States))

    1991-01-01

    Several properties of the Fabry-Perot-type open resonator used in the quasioptical gyrotron (QOG) and the quasioptical induced resonance electron cyclotron (IREC) maser are derived. The electric fields of the normal modes are given for the general case of the resonator axis tilted with respect to the direction perpendicular to the electron beam axis. The ohmic quality factor and the power dissipated in the mirrors are derived, as is the energy stored in the resonator. The time dependence of the mirror heating, relevant for pulsed experiments, is also derived. The formulae are applied to an example of current relevance, the quasioptical IREC maser resonator.

  15. 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.

  16. Aberration correction of unstable resonators

    NASA Technical Reports Server (NTRS)

    Lang, Robert J. (inventor)

    1994-01-01

    Construction of aspheric reflectors for unstable resonator lasers to provide an arbitrary laser mode inside the resonator to correct aberrations of an output beam by the construction of the shape of an end reflector opposite the output reflector of the resonator cavity, such as aberrations resulting from refraction of a beam exiting the solid of the resonator having an index of refraction greater than 1 or to produce an aberration in the output beam that will precisely compensate for the aberration of an optical train into which the resonator beam is coupled.

  17. 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.

  18. Resonant Magnetic Vortices

    E-print Network

    Yves Décanini; Antoine Folacci

    2002-12-23

    By using the complex angular momentum method, we provide a semiclassical analysis of electron scattering by a magnetic vortex of Aharonov-Bohm-type. Regge poles of the $S$-matrix are associated with surface waves orbiting around the vortex and supported by a magnetic field discontinuity. Rapid variations of sharp characteristic shapes can be observed on scattering cross sections. They correspond to quasibound states which are Breit-Wigner-type resonances associated with surface waves and which can be considered as quantum analogues of acoustic whispering-gallery modes. Such a resonant magnetic vortex could provide a new kind of artificial atom while the semiclassical approach developed here could be profitably extended in various areas of the physics of vortices.

  19. Gravito-electromagnetic resonances

    E-print Network

    Tsagas, Christos G

    2011-01-01

    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...

  20. Resonance enhanced turbulent transport

    SciTech Connect

    Newton, Andrew P. L.; Kim, Eun-jin [Department of Applied Mathematics, University of Sheffield, Sheffield, S3 7RH (United Kingdom)

    2007-12-15

    The effect of oscillatory shear flows on turbulent transport of passive scalar fields is studied by numerical computations based on the results provided by E. Kim [Physics of Plasmas 13, 022308 (2006)]. Turbulent diffusion is found to depend crucially on the competition between suppression due to shearing and enhancement due to resonances, depending on the characteristic time and length scales of shear flow and turbulence. Enhancements in transport occur for turbulence with finite memory time either due to Doppler or parametric resonances. Scalings of turbulence amplitude and transport are provided in different parameter spaces. The results suggest that oscillatory shear flows are not only less efficient in regulating turbulence, but also can enhance the value of turbulent diffusion, accelerating turbulent transport.

  1. Resonances of coronal loops

    NASA Technical Reports Server (NTRS)

    Hollweg, J. V.

    1984-01-01

    It is pointed out that any theoretical demonstration that the solar corona can be heated by waves requires a demonstration that the required energies can actually be carried from the convection zone to the corona by waves. In addition, it must be shown that the waves can dissipate their energy into heat in the corona. The present investigation is concerned specifically with the heating of closed magnetic structures in the corona, taking into account coronal loops or active region loops. Attention is given to the MHD Alfven wave. It is shown analytically that coronal active region loops can behave much like interference filters. The coronal part of the loop acts like a resonant cavity for Alfven waves. When the resonances are excited, large energy fluxes can be carried into the loop by Alfven waves which are generated in the solar convection zone. It is estimated that the energy fluxes can power the observed loops.

  2. Parallel Magnetic Resonance Imaging

    E-print Network

    Uecker, Martin

    2015-01-01

    The main disadvantage of Magnetic Resonance Imaging (MRI) are its long scan times and, in consequence, its sensitivity to motion. Exploiting the complementary information from multiple receive coils, parallel imaging is able to recover images from under-sampled k-space data and to accelerate the measurement. Because parallel magnetic resonance imaging can be used to accelerate basically any imaging sequence it has many important applications. Parallel imaging brought a fundamental shift in image reconstruction: Image reconstruction changed from a simple direct Fourier transform to the solution of an ill-conditioned inverse problem. This work gives an overview of image reconstruction from the perspective of inverse problems. After introducing basic concepts such as regularization, discretization, and iterative reconstruction, advanced topics are discussed including algorithms for auto-calibration, the connection to approximation theory, and the combination with compressed sensing.

  3. CMOS micromechanical resonator oscillator

    Microsoft Academic Search

    C. T.-C. Nguyen; R. T. Howe

    1993-01-01

    A completely monolithic high-Q oscillator, fabricated via a combined CMOS plus surface micromachining technology, is described, for which the oscillation frequency is controlled by a polysilicon micromechanical resonator to achieve stability and phase noise performance comparable to those of quartz crystal oscillators. It is shown that the closed-loop, steady-state oscillation amplitude of this oscillator can be controlled through the DC-bias

  4. 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.

  5. Resonance phenomena near thresholds

    SciTech Connect

    Persson, E.; Mueller, M.; Rotter, I. [Forschungszentrum Rossendorf, Institut fuer Kern- und Hadronenphysik, D-01314 Dresden (Germany)] [Forschungszentrum Rossendorf, Institut fuer Kern- und Hadronenphysik, D-01314 Dresden (Germany); [Technische Universitaet Dresden, Institut fuer Theoretische Physik, D-01062 Dresden (Germany)

    1996-06-01

    The trapping effect is investigated close to the elastic threshold. The nucleus is described as an open quantum mechanical many-body system embedded in the continuum of decay channels. An ensemble of compound nucleus states with states below and above threshold is investigated in an energy-dependent formalism. It is shown that the states below threshold can trap the resonance ones and also that they can directly influence the scattering cross section. {copyright} {ital 1996 The American Physical Society.}

  6. Cardiac Magnetic Resonance Imaging

    Microsoft Academic Search

    Michael Jerosch-Herold; Ravi Teja Seethamraju; Carsten Rickers

    Magnetic resonance imaging (MRI) has proven to be extremely versatile and useful for studying cardiac anatomy and function,\\u000a both for providing a deeper understanding of cardiac physiology and as a means to diagnose cardiac diseases. The capabilities\\u000a of MRI as a tomographic imaging modality to capture, with high spatial resolution, the anatomy of 3D structures was already\\u000a well appreciated before

  7. Resonant Ultrasound Spectroscopy

    Microsoft Academic Search

    John Louis Sarrao

    1993-01-01

    Resonant Ultrasound Spectroscopy (RUS) measurements of the structural phase transition in La_ {rm 2-x}Sr_{ rm x}CuO_4 are presented. After a review of the RUS technique and the description of structural phase transitions within a Ginzburg -Landau formalism, we discuss measurements of the complete elastic moduli of La_2CuO _4 and La_{1.86} Sr_{0.14}CUO _4. Large modulus-specific softening is observed in the vicinity

  8. 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.

  9. Ghost-vibrational resonance

    E-print Network

    S Rajamani; S Rajasekar; MAF Sanjuán

    2014-04-22

    Ghost-stochastic resonance is a noise-induced resonance at a fundamental frequency missing in the input signal. We investigate the effect of a high-frequency, instead of a noise, in a single Duffing oscillator driven by a multi-frequency signal $F(t)= \\sum^n_{i=1} f_i \\cos(\\omega_i + \\Delta \\omega_0)t$, $\\omega_i=(k+i-1)\\omega_0$, where $k$ is an integer greater than or equal to two. We show the occurrence of a high-frequency induced resonance at the missing fundamental frequency $\\omega_0$. For the case of the two-frequency input signal, we obtain an analytical expression for the amplitude of the periodic component with the missing frequency. We present the influence of the number of forces $n$, the parameter $k$, the frequency $\\omega_0$ and the frequency shift $\\Delta \\omega_0$ on the response amplitude at the frequency $\\omega_0$. We also investigate the signal propagation in a network of unidirectionally coupled Duffing oscillators. Finally, we show the enhanced signal propagation in the coupled oscillators in absence of a high-frequency periodic force.

  10. 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.

  11. 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.

  12. Natural parity resonances in ??+?-

    NASA Astrophysics Data System (ADS)

    Amelin, D.; Berdnikov, E.; Bityukov, S.; Borisov, G.; Bugg, D. V.; Gouz, Yu; Dorofeev, V.; Dzhelyadin, R.; Ekimov, A.; Karyukhin, A.; Kachaev, I.; Khokhlov, Yu; Konstantinov, V.; Kopikov, A.; Kostyukhin, V.; Likhoded, S.; Matveev, V.; Ostankov, A.; Polyakov, B.; Ryabchikov, D.; Sekhniaidze, G.; Solovyanov, O.; Solodkov, A.; Starchenko, E.; Tskhadadze, E.; Vishnevski, N.; Vlasov, E.; Zaitsev, A.; VES Collaboration

    2000-03-01

    Results of a partial wave analysis of the ??+?- final state are presented using 4.2×10 4 events with | t|<0.2 GeV 2, collected at the VES setup; the reaction is ?-p? ?-?+?n from a beryllium target. The data reveal resonant structures, which are identified by phase motion as well as peaks in intensities of partial waves. The f2(1565) meson, also called the AX meson, is observed in decays to [ a2(1302) ?] L=1 . The parameters obtained from a fit with a Breit-Wigner amplitude are M=1550±20 MeV with ?=130±40 MeV. The higher mass f2 resonances are also discussed. For JP=3 -, the well known ?3(1690) is seen in decays to both a2(1320) ? and ?? channels. The complex behaviour of 3 -- amplitudes at higher masses is described best by introducing two additional resonant poles near 2.14 and 2.30 GeV. There is evidence for an f4(2300) meson, decaying dominantly to [ f2?] L=3 .

  13. Real-time synchronous imaging of electromechanical resonator mode and equilibrium profiles.

    PubMed

    Linzon, Y; Krylov, S; Ilic, B; Southworth, D R; Barton, R A; Cipriany, B R; Cross, J D; Parpia, J M; Craighead, H G

    2010-08-01

    Interferometric imaging of normal mode dynamics in electromechanical resonators, oscillating in the rf regime, is demonstrated by synchronous imaging with a pulsed nanosecond laser. Profiles of mechanical modes in suspended thin film structures and their equilibrium profiles are measured through all-optical Fabry-Perot reflectance fits to the temporal traces. As a proof of principle, the mode patterns of a microdrum silicon resonator are visualized, and the extracted vibration modes and equilibrium profile show good agreement with numerical estimations. PMID:20680089

  14. Scattering phase shift and resonance properties on the lattice: an introduction

    E-print Network

    Prelovsek, S; Mohler, D

    2011-01-01

    We describe the method for extracting the elastic scattering phase shift from a lattice simulation at an introductory level, for non-lattice practitioners. We consider the scattering in a resonant channel, where the resulting phase shift delta(s) allows the lattice determination of the mass and the width of the resonance from a Breit-Wigner type fit. We present the method for the example of P-wave pi-pi scattering in the rho meson channel.

  15. Multispectral magnetic resonance image analysis.

    PubMed

    Vannier, M W; Butterfield, R L; Rickman, D L; Jordan, D M; Murphy, W A; Biondetti, P R

    1987-01-01

    Multiecho magnetic resonance (MR) scanning produces tomographic images with approximately equal morphologic information but varying gray scales at the same anatomic level. Multispectral image classification techniques, originally developed for satellite imaging, have recently been applied to MR tissue characterization. Statistical assessment of multispectral tissue classification techniques has been used to select the most promising of several alternative methods. MR examinations of the head and body, obtained with a 0.35, 0.5, or 1.5T imager, comprised data sets with at least two pulse sequences yielding three images at each anatomical level: (1) TR = 0.3 sec, TE = 30 msec, (2) TR = 1.5, TE = 30, (3) TR = 1.5, TE = 120. Normal and pathological images have been analyzed using multispectral analysis and image classification. MR image data are first subjected to radiometric and geometric corrections to reduce error resulting from (1) instrumental variations in data acquisition, (2) image noise, and (3) misregistration. Training regions of interest (ROI) are outlined in areas of normal (gray and white matter, CSF) and pathological tissue. Statistics are extracted from these ROIs and classification maps generated using table lookup, minimum distance to means, maximum likelihood, and cluster analysis. These synthetic maps are then compared pixel by pixel with manually prepared classification maps of the same MR images. Using these methods, the authors have found that: (1) both supervised and unsupervised classification techniques yielded theme maps (class maps) which demonstrated tissue characteristic signatures and (2) tissue classification errors found in computer-generated theme maps were due to subtle gray scale changes present in the original MR data sets arising from radiometric inhomogeneity and spatial nonuniformity. PMID:3691157

  16. 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.

  17. Excitation of Giant Monopole Resonance in $^{208}$Pb and $^{116}$Sn Using Inelastic Deuteron Scattering

    E-print Network

    D. Patel; U. Garg; M. Itoh; H. Akimune; G. P. A. Berg; M. Fujiwara; M. N. Harakeh; C. Iwamoto; T. Kawabata; K. Kawase; J. T. Matta; T. Murakami; A. Okamoto; T. Sako; K. W. Schlax; K. Takahashi; M. White; M. Yosoi

    2014-06-26

    The excitation of the isoscalar giant monopole resonance (ISGMR) in $^{116}$Sn and $^{208}$Pb has been investigated using small-angle (including $0^\\circ$) inelastic scattering of 100 MeV/u deuteron and multipole-decomposition analysis (MDA). The extracted strength distributions agree well with those from inelastic scattering of 100 MeV/u $\\alpha$ particles. These measurements establish deuteron inelastic scattering at E$_d \\sim$ 100 MeV/u as a suitable probe for extraction of the ISGMR strength with MDA, making feasible the investigation of this resonance in radioactive isotopes in inverse kinematics.

  18. Nonlinear wave-particle resonant interaction in the radiation belts: Landau resonance vs. fundamental cyclotron resonance

    NASA Astrophysics Data System (ADS)

    Krasnoselskikh, V.; Artemyev, A.; Agapitov, O. V.; Mourenas, D.

    2013-12-01

    We present selected THEMIS observations of highly-oblique and large amplitude chorus waves at medium latitudes. The major part of observed waves propagates at nearly-electrostatic mode with normal angles close to resonance cone. We use test particle simulations and analytical theory to estimate efficiency of nonlinear particle acceleration by these waves via Landau and fundamental cyclotron resonances. We show that trapping into the Landau resonance corresponds to a decrease of electron equatorial pitch-angles, while trapping into the first cyclotron resonance increases electron equatorial pitch-angles. For 100 keV electrons, the energy gain is larger for the trapping due to Landau resonance. Moreover, trapping into the Landau resonance is accessible for a wider range of initial pitch-angles in comparison with the fundamental resonance.

  19. Infrared Extraction Change for the NSLS-II Storage Ring

    SciTech Connect

    Blednykh,A.; Carr, L.; Coburn, D.; Krinsky, S.

    2009-05-04

    The short- and long-range wakepotentials have been studied for the design of the infrared (IR) extraction chamber with large full aperture: 67mm vertical and 134mm horizontal. The IR-chamber will be installed within a 2.6m long wide-gap bending magnet with 25m bend radius. Due to the large bend radius it is difficult to separate the light from the electron trajectory. The required parameters of the collected IR radiation at the extraction mirror are {approx}50mrad horizontal and {approx}25mrad vertical (full radiation opening angles). If the extraction mirror is seen by the beam, resonant modes are generated in the chamber. In this paper, we present the detailed calculated impedance for the design of the far-IR chamber, and show that placing the extraction mirror in the proper position eliminates the resonances. In this case, the impedance reduces to that of a simple tapered structure, which is acceptable in regard to its impact on the electron beam.

  20. MAGNETIC RESONANCE IN CHEMISTRY Magn. Reson. Chem. 37, 653661 (1999)

    E-print Network

    Hudlicky, Tomas

    alkaloids (Scheme 1) extracted from the opium poppy Papaver somniferum are known worldwide for their broad approach that would compete economically with the low cost of its extraction from opium poppy has yet

  1. Extractable work from correlations

    E-print Network

    Martí Perarnau-Llobet; Karen V. Hovhannisyan; Marcus Huber; Paul Skrzypczyk; Nicolas Brunner; Antonio Acín

    2014-11-11

    Work and quantum correlations are two fundamental resources in thermodynamics and quantum information theory. In this work we study how to use correlations among quantum systems to optimally store work. We analyse this question for isolated quantum ensembles, where the work can be naturally divided into two contributions: a local contribution from each system, and a global contribution originating from correlations among systems. We focus on the latter and consider quantum systems which are locally thermal, thus from which any extractable work can only come from correlations. We compute the maximum extractable work for general entangled states, separable states, and states with fixed entropy. Our results show that while entanglement gives an advantage for small quantum ensembles, this gain vanishes for a large number of systems.

  2. 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.

  3. [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.

  4. Ion extraction system optimization

    SciTech Connect

    Cavenago, Marco [INFN-LNL, v.le dell'Universita n 2, I-35020, Legnaro (Italy)

    2013-07-18

    The extraction of a beam from ion sources is dominated by the strong space charge of the beam, due to the initial low speed of the particles. Several mathematical and computational issues are discussed, with reference to a diode design based on thin anode lens effect, yielding a parallel beam at its exit, which is the first block of many high current electrostatic accelerators. Perturbation to uniform current density are analyzed. Effect of a thick anode lens is also treated.

  5. 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.

  6. 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.

  7. Graph-Cut Energy Minimization for Object Extraction in MRCP Medical Images

    Microsoft Academic Search

    Rajasvaran Logeswaran; Dongho Kim; Jungwhan Kim; Keechul Jung; Bundo Song

    Bile duct identification and extraction in magnetic resonance cholangiopancreatography (MRCP) images, is a necessary step\\u000a in the development of computer-aided diagnosis systems using such images. MRCP is becoming the de facto modality in the diagnosis\\u000a of biliary diseases and even in the pre-surgical workup for liver transplants. The energy minimization graph-cut method is\\u000a a proven technique in the extraction of

  8. 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

  9. Pressure dependent resonant frequency of micromechanical drumhead resonators

    SciTech Connect

    Southworth, D. R.; Craighead, H. G.; Parpia, J. M. [Center for Materials Research, Cornell University, Ithaca, New York 14853 (United States)

    2009-05-25

    We examine the relationship between squeeze film effects and resonance frequency in drum-type resonators. We find that the resonance frequency increases linearly with pressure as a result of the additional restoring force contribution from compression of gas within the drum cavity. We demonstrate trapping of the gas by squeeze film effects and geometry. The pressure sensitivity is shown to scale inversely with cavity height and sound radiation is found to be the predominant loss mechanism near and above atmospheric pressure. Drum resonators exhibit linearity and sensitivity suitable to barometry from below 10 Torr up to several atmospheres.

  10. Innovative Drying and Nutrients Extraction

    E-print Network

    to conventional techniques. The research will also quantify the new technology's energy savings for the extraction of the dried vegetable matter and extracts using the new technology as compared to thermal drying methods

  11. Two-dimensional nuclear magnetic resonance petrophysics.

    PubMed

    Sun, Boqin; Dunn, Keh-Jim

    2005-02-01

    Two-dimensional nuclear magnetic resonance (2D NMR) opens a wide area for exploration in petrophysics and has significant impact to petroleum logging technology. When there are multiple fluids with different diffusion coefficients saturated in a porous medium, this information can be extracted and clearly delineated from CPMG measurements of such a system either using regular pulsing sequences or modified two window sequences. The 2D NMR plot with independent variables of T2 relaxation time and diffusion coefficient allows clear separation of oil and water signals in the rocks. This 2D concept can be extended to general studies of fluid-saturated porous media involving other combinations of two or more independent variables, such as chemical shift and T1/T2 relaxation time (reflecting pore size), proton population and diffusion contrast, etc. PMID:15833623

  12. Proton Spin Structure in the Resonance Region

    SciTech Connect

    F. R. Wesselmann; K. Slifer; S. Tajima; A. Aghalaryan; A. Ahmidouch; R. Asaturyan; F. Bloch; W. Boeglin; P. Bosted; C. Carasco; R. Carlini; J. Cha; J. P. Chen; M. E. Christy; L. Cole; L. Coman; D. Crabb; S. Danagoulian; D. Day; J. Dunne; M. Elaasar; R. Ent; H. Fenker; E. Frlez; L. Gan; D. Gaskell; J. Gomez; B. Hu; M. K. Jones; J. Jourdan; C. Keith; C. E. Keppel; M. Khandaker; A. Klein; L. Kramer; Y. Liang; J. Lichtenstadt; R. Lindgren; D. Mack; P. McKee; D. McNulty; D. Meekins; H. Mkrtchyan; R. Nasseripour; I. Niculescu; K. Normand; B. Norum; D. Pocanic; Y. Prok; B. Raue; J. Reinhold; J. Roche; D. Rohe; O. A. Rondon; N. Savvinov; B. Sawatzky; M. Seely; I. Sick; C. Smith; G. Smith; S. Stepanyan; L. Tang; G. Testa; W. Vulcan; K. Wang; G. Warren; S. Wood; C. Yan; L. Yuan; Junho Yun; Markus Zeier; Hong Guo Zhu

    2006-10-11

    The RSS collaboration has measured the spin structure functions g{sub 1} and g{sub 2} of the proton at Jefferson Lab using the lab's polarized electron beam, the Hall C HMS spectrometer and the UVa polarized solid target. The asymmetries A{sub parallel} and A{sub perp} were measured at the elastic peak and in the region of the nucleon resonances (1.085 GeV < W < 1.910 GeV) at an average four momentum transfer of Q{sup 2} = 1.3 GeV{sup 2}. The extracted spin structure functions and their kinematic dependence make a significant contribution in the study of higher-twist effects and polarized duality tests.

  13. Resonant ultrasound spectroscopy and homogeneity in polycrystals.

    PubMed

    Kaplan, Gunes; Darling, T W; McCall, K R

    2009-01-01

    Resonant ultrasound spectroscopy (RUS) is capable of determining the bulk elastic properties of a solid from its characteristic vibration frequencies, given the dimensions, density and shape of the sample. The model used for extracting values of the elastic constants assumes perfect homogeneity, which can be approximated by average-isotropic polycrystals. This approximation is excellent in the small grain regime assumed for most averaging procedures, but for real samples with indeterminate grain size distributions, it is not clear where the approximation breaks down. RUS measurements were made on pure copper samples where the grain size distribution was changed by progressive heat treatments in order to find a quantitative limit for the loss of homogeneity. It is found that when a measure of the largest grains is 15% of the sample's smallest dimension, the deviation in RUS fits indicates elastic inhomogeneity. PMID:18804831

  14. Nuclear Resonance Fluorescence Measurements of High Explosives

    SciTech Connect

    Caggiano, Joseph A.; Warren, Glen A.; Korbly, Steve; Hasty, R.; Klimenko, A.; Park, William H.

    2007-12-31

    Pacific Northwest National Laboratory and Passport Systems have collaborated to perform Nuclear Resonance Fluorescence experiments using several high quality high-explosive simulant samples. These measurements were conducted to determine the feasibility of finding and characterizing high explosive material by NRF interrogation. Electron beams of 5.1, 5.3, 8, and 10 MeV were used to produce bremsstrahlung photon beams, which irradiated the samples. The gamma-ray spectra were collected using high-purity germanium detectors. Nitrogen-to-carbon ratios of the high-explosive simulants were extracted from the 5.1 and 5.3 MeV data and compare favorably with accepted values. Analysis of the 8 and 10 MeV data is in progress; preliminary isotopic comparisons within the samples are consistent with the expected results.

  15. Low B field magneto-phonon resonances in single-layer and bilayer graphene.

    PubMed

    Neumann, Christoph; Reichardt, Sven; Drögeler, Marc; Terrés, Bernat; Watanabe, Kenji; Taniguchi, Takashi; Beschoten, Bernd; Rotkin, Slava V; Stampfer, Christoph

    2015-03-11

    Many-body effects resulting from strong electron-electron and electron-phonon interactions play a significant role in graphene physics. We report on their manifestation in low B field magneto-phonon resonances in high-quality exfoliated single-layer and bilayer graphene encapsulated in hexagonal boron nitride. These resonances allow us to extract characteristic effective Fermi velocities, as high as 1.20 × 10(6) m/s, for the observed "dressed" Landau level transitions, as well as the broadening of the resonances, which increases with the Landau level index. PMID:25646665

  16. Combination of matrix solid-phase dispersion extraction and direct on-line liquid chromatography-nuclear magnetic resonance spectroscopy-tandem mass spectrometry as a new efficient approach for the rapid screening of natural products: application to the total asterosaponin fraction of the starfish Asterias rubens.

    PubMed

    Sandvoss, M; Weltring, A; Preiss, A; Levsen, K; Wuensch, G

    2001-05-11

    A combination of matrix solid-phase dispersion extraction (MSPD) and LC-NMR-MS hyphenation is proposed as a rapid screening method of natural products for unknown compounds. In this report, this new analytical approach is applied for the first time. MSPD represents a significant simplification compared to classical extraction procedures and is thus an excellent complement to the fast and powerful LC-NMR-MS: MSPD yields extracts suitable for LC-NMR-MS in one simple preparation step, while LC-NMR-MS yields a wealth of information in one single chromatographic run. The suitability of this technique to characterise glycosidic compounds in the molecular mass range of 1200 to 1400 a.m.u. is demonstrated. The information on the number of exchangeable protons provided by an additional back-exchange experiment proved to be particularly valuable for structural elucidation. The possibility of semi-quantitative LC-NMR measurements through methyl signals H(3)-18 and 19 of the steroidal skeleton is demonstrated and is ensuingly used to provide relative quantitative data of the steroid oligosaccharide fraction. PMID:11403494

  17. Collisional activation of ions by off-resonance irradiation in ion cyclotron resonance spectrometry

    NASA Astrophysics Data System (ADS)

    Shin, Seung Koo; Han, Seung-Jin; Seo, Jongcheol

    2009-06-01

    Collisional activation of ions in the ion cyclotron resonance (ICR) cell by short off-resonance burst irradiation (ORBI) was studied by time-resolved photodissociation of the meta-bromotoluene radical cation. Off-resonance chirp or single-frequency burst was applied for 2 ms to the probe ion in the presence of Ar buffer gas. The amount of internal energy imparted to the probe ion by collision under ORBI was precisely determined by time-resolved photodissociation spectroscopy. The rate of unimolecular dissociation of the probe ion following the photolysis at 532 nm was measured by monitoring the real-time appearance of the C7H7+ product ion. The internal energy of the probe ion was extracted from the known rate-energy curve. To help understand the collisional activation of an ion under ORBI, we simulated the radial trajectory of the ion using Green's method. The calculated radial kinetic energy was converted to the collision energy in the center-of-mass frame, and the collision frequency was estimated by using a reactive hard-sphere collision model with an ion-induced dipole potential. Both experiments and trajectory simulations suggest that chirp irradiation leads to less collisional activation of ions than other waveforms.

  18. CO2 large-area discharge laser using an unstable-waveguide hybrid resonator

    Microsoft Academic Search

    P. E. Jackson; H. J. Baker; D. R. Hall

    1989-01-01

    A one-dimensional unstable resonator combining free-space and waveguide propagation is used to efficiently extract power from a large-area gain medium in a slab waveguide COâ laser. A power of 240 W in a near-diffraction-limited beam has been attained at 12% conversion efficiency from a 38 cm gain length in a compact sealed-off laser head, corresponding to a specific power extraction

  19. CO2 large-area discharge laser using an unstable-waveguide hybrid resonator

    Microsoft Academic Search

    P. E. Jackson; H. J. Baker; D. R. Hall

    1989-01-01

    A one-dimensional unstable resonator combining free-space and waveguide propagation is used to efficiently extract power from a large-area gain medium in a slab waveguide CO2 laser. A power of 240 W in a near-diffraction-limited beam has been attained at 12% conversion efficiency from a 38 cm gain length in a compact sealed-off laser head, corresponding to a specific power extraction

  20. Electroexcitation of nucleon resonances

    SciTech Connect

    Inna Aznauryan, Volker D. Burkert

    2012-01-01

    We review recent progress in the investigation of the electroexcitation of nucleon resonances, both in experiment and in theory. The most accurate results have been obtained for the electroexcitation amplitudes of the four lowest excited states, which have been measured in a range of Q2 up to 8 and 4.5 GeV2 for the Delta(1232)P33, N(1535)S11 and N(1440)P11, N(1520)D13, respectively. These results have been confronted with calculations based on lattice QCD, large-Nc relations, perturbative QCD (pQCD), and QCD-inspired models. The amplitudes for the Delta(1232) indicate large pion-cloud contributions at low Q2 and don't show any sign of approaching the pQCD regime for Q2<7 GeV2. Measured for the first time, the electroexcitation amplitudes of the Roper resonance, N(1440)P11, provide strong evidence for this state as a predominantly radial excitation of a three-quark (3q) ground state, with additional non-3-quark contributions needed to describe the low Q2 behavior of the amplitudes. The longitudinal transition amplitude for the N(1535)S11 was determined and has become a challenge for quark models. Explanations may require large meson-cloud contributions or alternative representations of this state. The N(1520)D13 clearly shows the rapid changeover from helicity-3/2 dominance at the real photon point to helicity-1/2 dominance at Q2 > 0.5 GeV2, confirming a long-standing prediction of the constituent quark model. The interpretation of the moments of resonance transition form factors in terms of transition transverse charge distributions in infinite momentum frame is presented.

  1. Overview of baryon resonances. Present status and perspectives

    NASA Astrophysics Data System (ADS)

    Downie, E. J.

    2014-06-01

    The quest to understand the physics of any system cannot be said to be complete as long as one cannot predict and fully understand its resonance spectrum. Despite this, due to the experimental challenge of the required double polarization measurements and the difficulty in achieving unambiguous, model-independent extraction and interpretation of the nucleon resonance spectrum of many broad and overlapping resonances, understanding of the structure and dynamics of the nucleon has suffered. The recent improvement in statistical quality and kinematic range of the data made available by such full-solid-angle systems as the CB and TAPS constellation at MAMI, coupled with the high flux polarized photon beam provided by the Glasgow Photon Tagger, and the excellent properties of the Mainz Frozen Spin Target, when paired with new developments in Partial Wave Analysis (PWA) methodology make this a very exciting and fruitful time in nucleon resonance studies. Here the recent influx of data and PWA developments are summarized, and the requirements for a complete, unambiguous PWA solution over the first and second resonance region are briefly reviewed.

  2. Cylindrical coils near self-resonance.

    PubMed

    Harpen, M D

    1993-10-01

    We present a model of birdcage resonator operation when the size of the resonator approaches a quarter wave length resulting in significant phase shifts along the current conducting elements. In the model resonators are treated as generalized transmission lines. Line termination determines whether the resonator is of the low pass or high pass type. The model correctly describes the dependence of resonant frequency on resonant mode number as well as the distribution of current along the length of the resonator. PMID:8255197

  3. 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.

  4. Nanotube resonator devices

    DOEpatents

    Jensen, Kenneth J; Zettl, Alexander K; Weldon, Jeffrey A

    2014-05-06

    A fully-functional radio receiver fabricated from a single nanotube is being disclosed. Simultaneously, a single nanotube can perform the functions of all major components of a radio: antenna, tunable band-pass filter, amplifier, and demodulator. A DC voltage source, as supplied by a battery, can power the radio. Using carrier waves in the commercially relevant 40-400 MHz range and both frequency and amplitude modulation techniques, successful music and voice reception has been demonstrated. Also disclosed are a radio transmitter and a mass sensor using a nanotube resonator device.

  5. Ellipsometric surface plasmon resonance

    NASA Astrophysics Data System (ADS)

    Hsu, Wei-Liang; Lee, Shu-Sheng; Lee, Chih-Kung

    2009-03-01

    We develop a new multifunctional optical biochip system that integrates an ellipsometer with a surface plasmon resonance (SPR) feature. This newly developed biochip biosensor, which we call ESPR for an ellipsometric SPR, provides us with a system to retrieve detailed information such as the optical properties of immobilized biomolecular monolayers, surface concentration variations of biomedical reactions, and kinetic affinity between biomolecules required for further biotech analysis. Our ESPR can also serve as both a research and development tool and a manufacturing tool for various biomedical applications.

  6. 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.

  7. Scanning thermal microwave resonance microscopy

    NASA Astrophysics Data System (ADS)

    Meckenstock, R.; Spoddig, D.; Dietzel, D.; Pelzl, J.

    2004-03-01

    Local detection of ferromagnetic resonance in magnetically ordered materials is achieved by local thermal modulation of the microwave resonance absorption with a scanning thermal microscope. A scanning thermal microwave resonance microscope was constructed based on a microwave bridge with an X-band cavity and a thermal nano-probe contacted to the sample at the wall of the cavity. The technique has been tested on an epitaxial iron film which exhibited lateral inhomogeneities due to a partial oxidation of iron. Different types of oxidation could be distinguished. The locally resolved ferromagnetic resonance spectra are compared with the result of an integral measurement using conventional detection techniques of the ferromagnetic resonance with the same set-up. The lateral resolution achievable with the thermally modulated ferromagnetic resonance measurements was about 200 nm for the investigated iron film.

  8. 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.

  9. 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

  10. Challenges in Managing Information Extraction

    ERIC Educational Resources Information Center

    Shen, Warren H.

    2009-01-01

    This dissertation studies information extraction (IE), the problem of extracting structured information from unstructured data. Example IE tasks include extracting person names from news articles, product information from e-commerce Web pages, street addresses from emails, and names of emerging music bands from blogs. IE is all increasingly…

  11. Solvent extraction in nuclear technology

    Microsoft Academic Search

    J. D. Navratil

    1986-01-01

    Some aspects of solvent extraction chemistry in the field of nuclear technology are briefly reviewed. Applications of solvent extraction in actinide recovery and purification, radionuclide production, and reactor materials preparation are summarized. The need for new, more selective, solvent extraction reagents is presented via examples of recent work with bifunctional organophosphorus reagents applied to the removal of actinides from acidic

  12. Photon decay of giant resonances

    Microsoft Academic Search

    F. E. Bertrand; J. R. Beene; M. L. Halbert

    1984-01-01

    Measurements have been made of the photon decay of the giant multipole resonances in ²°⁸Pb. The giant resonances were excited by inelastic scattering of 380 MeV ¹⁷O projectile and the photons were detected in the ORNL Spin Spectrometer. The results show a quadrupole resonance ground state gamma branch of 20% while only less than or equal to 2% of the

  13. Resonance capture at arbitrary inclination

    NASA Astrophysics Data System (ADS)

    Namouni, F.; Morais, M. H. M.

    2015-01-01

    Resonance capture is studied numerically in the three-body problem for arbitrary inclinations. Massless particles are set to drift from outside the 1:5 resonance with a Jupiter-mass planet thereby encountering the web of the planet's diverse mean motion resonances. Randomly constructed samples explore parameter space for inclinations from 0 to 180° with 5° increments totalling nearly 6 × 105 numerical simulations. 30 resonances internal and external to the planet's location are monitored. We find that retrograde resonances are unexpectedly more efficient at capture than prograde resonances and that resonance order is not necessarily a good indicator of capture efficiency at arbitrary inclination. Capture probability drops significantly at moderate sample eccentricity for initial inclinations in the range [10°,110°]. Orbit inversion is possible for initially circular orbits with inclinations in the range [60°,130°]. Capture in the 1:1 co-orbital resonance occurs with great likelihood at large retrograde inclinations. The planet's orbital eccentricity, if larger than 0.1, reduces the capture probabilities through the action of the eccentric Kozai-Lidov mechanism. A capture asymmetry appears between inner and outer resonances as prograde orbits are preferentially trapped in inner resonances. The relative capture efficiency of retrograde resonance suggests that the dynamical lifetimes of Damocloids and Centaurs on retrograde orbits must be significantly larger than those on prograde orbits implying that the recently identified asteroids in retrograde resonance, 2006 BZ8, 2008 SO218, 2009 QY6 and 1999 LE31 may be among the oldest small bodies that wander between the outer giant planets.

  14. Mass formula for baryon resonances

    Microsoft Academic Search

    Eberhard Klempt

    2002-01-01

    Light-baryon resonances with u, d, and s quarks only can be classified using the nonrelativistic quark model. When we assign intrinsic orbital angular momenta L and spin S to baryon resonances with total angular momenta J, we make the following observations: plotting the squared masses of the light-baryon resonances against these intrinsic orbital angular momenta L, Delta*'s with even and

  15. 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

  16. 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.

  17. Fano resonances in magnetic metamaterials

    SciTech Connect

    Naether, Uta; Molina, Mario I. [Departmento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile) and Center for Optics and Photonics (CEFOP), Casilla 4016, Concepcion (Chile)

    2011-10-15

    We study the scattering of magnetoinductive plane waves by internal (external) capacitive (inductive) defects coupled to a one-dimensional split-ring resonator array. We examine a number of simple defect configurations where Fano resonances occur and study the behavior of the transmission coefficient as a function of the controllable external parameters. We find that for embedded capacitive defects, the addition of a small amount of coupling to second neighbors is necessary for the occurrence of Fano resonance. For external inductive defects, Fano resonances are commonplace, and they can be tuned by changing the relative orientation or distance between the defect and the SSR array.

  18. Tune space manipulations in jumping depolarizing resonances

    SciTech Connect

    Ratner, L.G.; Ahrens, L.A.

    1987-01-01

    In February 1986, the AGS polarized beam reached a momentum of 22 GeV/c with a 45% polarization and an intensity of 1 to 2 x 10/sup 10/ polarized protons per pulse at a repetition rate of 2.1 seconds. In order to achieve this, one had to overcome the effect of some 40 depolarizing resonances. In our first commissioning run in 1984, we had reached 16.5 GeV/c using, with suitable modifications, the conventional techniques first used at the Argonne ZGS. This worked well, but we found that the fast tune shifts required to cross the intrinsic depolarizing resonances were causing an increase in beam emittance which led to the need for stronger corrections later in the cycle and to diminished extraction efficiency. For the 1986 run, we were prepared to minimize this emittance growth by the application of slow quadrupole pulses to change the region in tune space in which we operated the first tune quads. In this paper we give a brief description of the conventional corrections, but our main emphasis is on the descriptions of tune space manipulations.

  19. Fullerenes in electron cyclotron resonance ion sources

    SciTech Connect

    Biri, S.; Fekete, E.; Kitagawa, A.; Muramatsu, M.; Janossy, A.; Palinkas, J. [Institute of Nuclear Research (ATOMKI), H-4026 Debrecen, Bem ter 18/C (Hungary); National Institute for Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Department of Experimental Physics, Technical University of Budapest, H-1521 Budapest, P.O. Box 91 (Hungary); Department of Experimental Physics, University of Debrecen, H-4026 Debrecen, Bem ter 18/A (Hungary)

    2006-03-15

    Fullerene plasmas and beams have been produced in our electron cyclotron resonance ion sources (ECRIS) originally designed for other purposes. The ATOMKI-ECRIS is a traditional ion source with solenoid mirror coils to generate highly charged ions. The variable frequencies NIRS-KEI-1 and NIRS-KEI-2 are ECR ion sources built from permanent magnets and specialized for the production of carbon beams. The paper summarizes the experiments and results obtained by these facilities with fullerenes. Continuous effort has been made to get the highest C{sub 60} beam intensities. Surprisingly, the best result was obtained by moving the C{sub 60} oven deep inside the plasma chamber, very close to the resonance zone. Record intensity singly and doubly charged fullerene beams were obtained (600 and 1600 nA, respectively) at lower C{sub 60} material consumption. Fullerene derivatives were also produced. We mixed fullerenes with other plasmas (N, Fe) with the aim of making new materials. Nitrogen encapsulated fullerenes (mass: 720+14=734) were successfully produced. In the case of iron, two methods (ferrocene, oven) were tested. Molecules with mass of 720+56=776 were detected in the extracted beam spectra.

  20. Nuclear Magnetic Resonance Gyroscope

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

    The navigation grade micro Nuclear Magnetic Resonance Gyroscope (micro-NMRG) being developed by the Northrop Grumman Corporation is concluding 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 poster will describe the history, operational principles, and design basics of the NMRG including an overview of the NSD designs developed and demonstrated in the DARPA gyro development program. General performance results from phases 3 and 4 will also be presented.

  1. Resonance between Cantor sets

    E-print Network

    Peres, Yuval

    2007-01-01

    Let $C_a$ be the central Cantor set obtained by removing a central interval of length $1-2a$ from the unit interval, and continuing this process inductively on each of the remaining two intervals. We prove that if $\\log b/\\log a$ is irrational, then \\[ \\dim(C_a+C_b) = \\min(\\dim(C_a) + \\dim(C_b),1), \\] where $\\dim$ is Hausdorff dimension. More generally, given two self-similar sets $K,K'$ in $\\RR$ and a scaling parameter $s>0$, if the dimension of the arithmetic sum $K+sK'$ is strictly smaller than $\\dim(K)+\\dim(K') \\le 1$ (``geometric resonance''), then there exists $r<1$ such that all contraction ratios of the similitudes defining $K$ and $K'$ are powers of $r$ (``algebraic resonance''). Our method also yields a new result on the projections of planar self-similar sets generated by an iterated function system that includes a scaled irrational rotation.

  2. 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.

  3. 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.

  4. 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.

  5. MAGNETIC RESONANCE IN CHEMISTRY Magn. Reson. Chem. 2001; 39: 137140

    E-print Network

    Collum, David B.

    -coupling constant for the I­S connection, fI is the resonance frequency of the I-nucleus, and fSi is the resonance frequency of the ith S-nucleus. This signal generates an expected HMQC peak for each I­S connection at (fSi, fI), where fSi and

  6. Magnetic Resonance Imaging and Magnetic Resonance Angiography of Vertebrobasilar Dolichoectasia

    Microsoft Academic Search

    Franz T. Aichner; Stephan R. Felber; Günther G. Birbamer; Andrea Posch

    1993-01-01

    We performed magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) in 16 patients with vertebrobasilar dolichoectasia (VBD). Five patients had compressive cranial nerve deficits and 11 patients presented with transient or permanent ischemic deficits related to the vertebrobasilar system. VBD did not present with distinct clinical findings and no clear correlation between basilar artery ectasia and the presence of

  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. 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.

  9. Simple and Inexpensive Classroom Demonstrations of Nuclear Magnetic Resonance and Magnetic Resonance Imaging.

    ERIC Educational Resources Information Center

    Olson, Joel A.; Nordell, Karen J.; Chesnik, Marla A.; Landis, Clark R.; Ellis, Arthur B.; Rzchowski, M. S.; Condren, S. Michael; Lisensky, George C.

    2000-01-01

    Describes a set of simple, inexpensive, classical demonstrations of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) principles that illustrate the resonance condition associated with magnetic dipoles and the dependence of the resonance frequency on environment. (WRM)

  10. 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.

  11. 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

  12. Basics of Resonance Chiral Theory

    SciTech Connect

    Portoles, J. [Instituto de Fisica Corpuscular, IFIC, CSIC-Universitat de Valencia, Edifici d'Instituts de Paterna, Apt. Correus 22085, E-46071 Valencia (Spain)

    2010-12-28

    We review the main components that have to be considered, within Resonance Chiral Theory, in the study of processes whose dynamics is dominated by hadron resonances. We show its application in the study of the {tau}{yields}{pi}{pi}{pi}{nu}{sub {tau}} decay.

  13. Closed loop resonator feedback system

    SciTech Connect

    Frieberg, R.J.

    1981-02-03

    A resonator feedback system is disclosed wherein the output from a resonator having adaptive optics is monitored by a detector within a feedback loop to provide electrical control signals to actuators attached to the adaptive optics to control the phase of the radiation within the resonator to produce an output beam having a near diffraction limited distribution. In one embodiment , a portion of the output beam is phase modulated at discrete frequencies and focused through an aperture onto a detector. Far field amplitude fluctuations at the focal point resulting from phase perturbations of the radiation within the resonator produces an amplitude varying electrical input signal which is synchronously detected with multidither signals utilized to impress the phase modulation to produce multicorrection signals. Actuators attached to the adaptive optics of the resonator are responsive to the multicorrection signals to provide phase corrections to the radiation within the resonator to produce an output beam having a near diffraction limited distribution. In a further embodiment, the radiation within the resonator is phase modulated and phase corrected to produce an output beam having a near diffraction limited distribution. In a further embodiment, radiation reflected from a remote target is monitored in accordance with the present invention to provide phase corrections to the radiation within the resonator to compensate for phase distortion in the output beam resulting from changes in the index of refraction of the atmosphere in the path of the output beam resulting from thermal blooming or the like.

  14. Triangular Fabry-Perot resonator

    Microsoft Academic Search

    Qasem Exirifard

    2010-01-01

    We show that the resonant frequencies of the Triangualr Fabry-Perot resonator\\u000aare directly sensitive to the parity-odd LIV terms of the photon sector of the\\u000aSME. With present technology we estimate that the parity odd parameters can be\\u000ameasured with a sensitivity better than parts in $10^{17}$.

  15. Giant resonances in Mg-24

    E-print Network

    Youngblood, David H.; Lui, YW; Clark, HL.

    1999-01-01

    The giant resonance region in Mg-24 was studied with inelastic scattering of 240 MeV alpha particles at small angles including 0 degrees. The giant resonance peak was found to extend up to E-X = 41 MeV. Isoscalar E0, E1, and E2 strength...

  16. Homoclinic bifurcation at resonant eigenvalues

    Microsoft Academic Search

    Shui-Nee Chow; Bo Deng; Bernold Fiedler

    1990-01-01

    We consider a bifurcation of homoclinic orbits, which is an analogue of period doubling in the limit of infinite period. This bifurcation can occur in generic two parameter vector fields when a homoclinic orbit is attached to a stationary point with resonant eigenvalues. The resonance condition requires the eigenvalues with positive\\/negative real part closest to zero to be real, simple,

  17. Micromechanical bulk acoustic wave resonator

    Microsoft Academic Search

    T. Mattila; A. Oja; H. Seppa; O. Jaakkola; J. Kiihamaki; H. Kattelus; M. Koskenvuori; P. Rantakari; I. Tittonen

    2002-01-01

    We describe the use of bulk acoustic mode in micromechanical silicon resonators operating at radio frequencies. Based on measured data from the fabricated resonator (fr?14 MHz, Q>100 000) we analyze the characteristic impedance and signal levels in such microdevices and compare the values with conventional quartz crystals. We find that the high impedance level of microresonators can be met with

  18. Niobium sputtered quarter wave resonators

    Microsoft Academic Search

    V. Palmieri; V. L. Ruzinov; S. Yu. Stark; O. B. Malishev; R. Preciso; A. M. Porcellato; L. Badan; J. S. Sokolowski; G. P. Buso; F. Chiurlotto; F. Poletto

    1993-01-01

    At LNL a research program on niobium sputtered copper quarter wave resonators is reaching its final stage. With respect to traditional superconducting QWRs (lead electroplated, bulk niobium and explosively bonded Nb\\/Cu cavities), higher performances and lower costs are expected for niobium sputtered copper QWRs. By obtaining high quality superconducting niobium films with good thickness uniformity inside the resonator it is

  19. Whispering Gallery Mode Optomechanical Resonator

    NASA Technical Reports Server (NTRS)

    Aveline, David C.; Strekalov, Dmitry V.; Yu, Nan; Yee, Karl Y.

    2012-01-01

    Great progress has been made in both micromechanical resonators and micro-optical resonators over the past decade, and a new field has recently emerged combining these mechanical and optical systems. In such optomechanical systems, the two resonators are strongly coupled with one influencing the other, and their interaction can yield detectable optical signals that are highly sensitive to the mechanical motion. A particularly high-Q optical system is the whispering gallery mode (WGM) resonator, which has many applications ranging from stable oscillators to inertial sensor devices. There is, however, limited coupling between the optical mode and the resonator s external environment. In order to overcome this limitation, a novel type of optomechanical sensor has been developed, offering great potential for measurements of displacement, acceleration, and mass sensitivity. The proposed hybrid device combines the advantages of all-solid optical WGM resonators with high-quality micro-machined cantilevers. For direct access to the WGM inside the resonator, the idea is to radially cut precise gaps into the perimeter, fabricating a mechanical resonator within the WGM. Also, a strategy to reduce losses has been developed with optimized design of the cantilever geometry and positions of gap surfaces.

  20. Resonating feathers produce courtship song

    PubMed Central

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

    2010-01-01

    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

  1. Resonance in rarefied gases

    NASA Astrophysics Data System (ADS)

    Struchtrup, Henning

    2012-11-01

    Dispersion and damping of ultrasound waves are a standard test for mathematical models of rarefied gas flows. Normally, one considers waves in semi-infinite systems in relatively large distance of the source. For a more complete picture, ultrasound propagation in finite closed systems of length L is studied by means of several models for rarefied gas flows: the Navier-Stokes-Fourier equations, Grad's 13 moment equations, the regularized 13 moment equations, and the Burnett equations. All systems of equations are considered in simple 1-D geometry with their appropriate jump and slip boundary conditions. Damping and resonance are studied in dependence of frequency and length. For small L, all wave modes contribute to the solution.

  2. Cryogenic Resonator Complex

    NASA Astrophysics Data System (ADS)

    Parshin, V. V.; Serov, E. A.; Bubnov, G. M.; Vdovin, V. F.; Koshelev, M. A.; Tretyakov, M. Yu.

    2014-01-01

    We describe a unique new-generation laboratory facility for studying dielectric parameters of gases and condensed media, as well as reflectivity of surfaces (reflection loss) in the frequency range 100-500 GHz and pressure interval from 10-3 Torr to the atmospheric pressure at temperatures of 4 to 370 K. The Fabry-Perot resonators with Q-factors of about 106, in which the studied gas, dielectric, or reflector are located, are the measuring elements of the facility. The backward-wave oscillator stabilized by the wideband phased-lock loop is the radiation source. Using this facility, we were able, in particular, to confirm the presence of water dimers in the atmosphere and study some materials for the reflectors of the "Millimetron" space observatory.

  3. 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.

  4. 21 CFR 73.30 - Annatto extract.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Annatto extract. 73.30 Section 73.30...FROM CERTIFICATION Foods § 73.30 Annatto extract. (a) Identity. (1) The color additive annatto extract is an extract prepared from...

  5. A potential commercial source of fucoxanthin extracted from the microalga Phaeodactylum tricornutum.

    PubMed

    Kim, Sang Min; Jung, Yu-Jin; Kwon, Oh-Nam; Cha, Kwang Hyun; Um, Byung-Hun; Chung, Donghwa; Pan, Cheol-Ho

    2012-04-01

    Fucoxanthin, one of the main marine carotenoids, is abundant in macro- and microalgae. Here, fucoxanthin was isolated and structurally identified as the major carotenoid in the diatom Phaeodactylum tricornutum through chromatographic and spectroscopic methods, such as liquid chromatography-positive-ion atmospheric pressure chemical ionization/mass spectroscopy and nuclear magnetic resonance. This pigment was quantified by reverse-phase high-performance liquid chromatography, and a number of extraction procedures were assessed to investigate the effect of solvent type, extraction time, temperature, and extraction method (maceration, ultrasound-assisted extraction, Soxhlet extraction, and pressurized liquid extraction). Among the investigated solvents, ethanol provided the best fucoxanthin extraction yield (15.71 mg/g freeze-dried sample weight). Fucoxanthin content in the extracts produced by the different methods was quite constant (15.42-16.51 mg/g freeze-dried sample weight) but increased steeply based on the percentage of ethanol in water, emphasizing the importance of ethanol in the extraction. The results indicate that P. tricornutum is a rich source of fucoxanthin (at least ten times more abundant than that in macroalgae) that is easily extracted with ethanol, suggesting potential applications in human and animal food, health, and cosmetics. PMID:22371063

  6. Photon decay of giant resonances

    SciTech Connect

    Bertrand, F.E.; Beene, J.R.; Halbert, M.L.

    1984-01-01

    Measurements have been made of the photon decay of the giant multipole resonances in /sup 208/Pb. The giant resonances were excited by inelastic scattering of 380 MeV /sup 17/O projectile and the photons were detected in the ORNL Spin Spectrometer. The results show a quadrupole resonance ground state gamma branch of 20% while only less than or equal to 2% of the GQR decay proceeds through the 2.6 MeV, 3/sup -/ state. Nearly one half of the GQR decay through a 3/sup -/ state at 4.974 MeV. Photon decay from the dipole and monopole resonances and high spin resonances (4+,6+) are also observed.

  7. Continuous layer gap plasmon resonators.

    PubMed

    Nielsen, Michael G; Gramotnev, Dmitri K; Pors, Anders; Albrektsen, Ole; Bozhevolnyi, Sergey I

    2011-09-26

    We demonstrate both theoretically and experimentally that a gold nanostrip supported by a thin dielectric (silicon dioxide) film and a gold underlay forms an efficient (Fabry-Perot) resonator for gap surface plasmons. Periodic nanostrip arrays are shown to exhibit strong and narrow resonances with nearly complete absorption and quality factors of ~15-20 in the near-infrared. Two-photon luminescence microscopy measurements reveal intensity enhancement factors of ~120 in the 400-nm-period array of 85-nm-wide gold strips atop a 23-nm-thick silica film at the resonance wavelength of ~770 nm. Excellent resonant characteristics, the simplicity of tuning the resonance wavelength by adjusting the nanostrip width and/or the dielectric film thickness and the ease of fabrication with (only) one lithography step required make the considered plasmonic configuration very attractive for a wide variety of applications, ranging from surface sensing to photovoltaics. PMID:21996871

  8. 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.

  9. 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.

  10. 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.

  11. Solid-state NMR analysis of soil organic matter fractions from integrated physical-chemical extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fractions of soil organic matter (SOM) are usually extracted from soil by either physical (size, density) or chemical (e.g., base, acid) procedures. In this study we used 13C nuclear magnetic resonance (NMR) spectroscopy to chemically characterize the fractions that were obtained by an integrated pr...

  12. Comparison of structure extraction methods for in vivo trabecular bone measurements

    Microsoft Academic Search

    A Laib; P Rüegsegger

    1999-01-01

    In vivo trabecular bone structure measurements have become available recently using high resolution quantitative computed tomography (3D-QCT) or magnetic resonance imaging. In this work different structure extraction and morphometric evaluation techniques are compared, which are of potential use for in vivo assessment of human cancellous bone structure. Given the spatial resolution of actual in vivo examination procedures, best results are

  13. SAR Calculations in Human Head Model Extracted from Thermal Infrared Images

    Microsoft Academic Search

    Akram Gasmelseed; Jasmy Yunus

    2010-01-01

    In electromagnetic dosimetry, anatomical human models are commonly obtained by segmentation of magnetic resonance imaging (MRI) or computed tomography (CT) scans. In this paper, a human head model extracted from thermal IR images is examined in terms of its applicability to specific absorption rate (SAR) calculations. Since thermal scans are two-dimensional (2-D) representation of surface temperature, this allows researchers to

  14. Nanoparticle arrays: From magnetic response to coupled plasmon resonances

    NASA Astrophysics Data System (ADS)

    Kravets, V. G.; Schedin, F.; Pisano, G.; Thackray, B.; Thomas, P. A.; Grigorenko, A. N.

    2014-09-01

    We study optical properties of optomagnetic metamaterials consisting of regular arrays of single and double Au nanodots (nanopillars). Using a combination of data from variable angle spectroscopic ellipsometry, transmission, and reflection measurements, we identify localized plasmon resonances of gold nanodots and measure their dependence on dot size and substrate type. We demonstrate that arrays of Au nanopillars can support narrow collective plasmon resonances coupled to in-plane and out-of-plane localized plasmon resonances. The spectral positions of these plasmon modes are extracted from the angular dependence of the transmission and reflection spectra for two beam polarizations. We show that nanoarrays exhibit dramatically different optical response on conductive and nonconductive substrates and study its angular dependence. The optical response of nanoarrays is described well by coupled dipole approximation. The procedure for extracting optical constants of metamaterials based on ellipsometry is discussed and applied to our samples resulting in a calculated negative index of refraction for double-dot arrays at green light.

  15. ?-Amylase-assisted extraction of polysaccharides from Panax ginseng.

    PubMed

    Sun, Lin; Wu, Di; Ning, Xin; Yang, Guang; Lin, Ziheng; Tian, Meihong; Zhou, Yifa

    2015-04-01

    In this paper, ?-amylase-assisted extraction was used to isolate the polysaccharide that remained in hot water-extracted ginseng. The yield of the polysaccharide was 9.0%, almost equal to that of the hot water-extracted polysaccharide. Using anion exchange and gel permeation chromatography, the polysaccharide was fractionated into a neutral polysaccharide fraction and six pectic fractions. The neutral fraction accounted for 76% of the polysaccharide and contained both amylopectin and amylose. The pectic polysaccharide fractions were identified to be arabinogalactan, type-I rhamnogalacturonan and homogalacturonan-type pectin by high-performance liquid chromatography, Fourier transform-infrared and nuclear magnetic resonance analysis. Structural and lymphocyte proliferation activity results showed that these polysaccharides were different from those extracted by hot water, indicating that ginseng contains complex polysaccharides with diverse structures, which results in its diverse pharmacological activities. The ?-amylase-assisted extraction is a novel method for preparing ginseng polysaccharides and could be applied toward the further study and exploration of ginseng. These findings provide technical and theoretical support for ginseng pharmacology. PMID:25616118

  16. 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.

  17. 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].

  18. Nonlinear optical whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Ilchenko, Vladimir (Inventor); Matsko, Andrey B. (Inventor); Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor)

    2005-01-01

    Whispering gallery mode (WGM) optical resonators comprising nonlinear optical materials, where the nonlinear optical material of a WGM resonator includes a plurality of sectors within the optical resonator and nonlinear coefficients of two adjacent sectors are oppositely poled.

  19. Electron paramagnetic resonance reveals age-related myosin structural changes in rat skeletal muscle fibers

    E-print Network

    Thomas, David D.

    assays showed that myosin molecules extracted from soleus muscle fibers of aged rats have a decreased muscle fibers DAWN A. LOWE,1,3 JACK T. SUREK,1 DAVID D. THOMAS,1,3 AND LADORA V. THOMPSON2,3 1 Department. Electron paramagnetic resonance reveals age-related myosin structural changes in rat skeletal muscle fibers

  20. Resonance Raman Spectra of Optical Purified (6,5) Nanotubes Sorted by Density Gradient Ultracentrifugation

    E-print Network

    Maruyama, Shigeo

    spectra using different excitation energies clearly reveal the existence of these minority species extraction of single-chirality SWNTs. Figure 1: Resonance Raman spectra (left, 488 nm laser excitation. Hersam. Nat. Nanotechnol. 1, 60 (2006) [2] K.Yanagi, Y. Miyata and H.Kataura, Appl. Phys. Express 1

  1. All-optical logic based on silicon micro-ring resonators.

    PubMed

    Xu, Qianfan; Lipson, Michal

    2007-02-01

    We demonstrate all-optical logic in a micron-size silicon ring resonator based on the free-carrier dispersion effect in silicon. We show AND and NAND operation at 310 Mbit/s with ~10-dB extinction ratio. The free-carrier-lifetime-limited bit-rate can be significantly improved by active carrier extraction. PMID:19532318

  2. Modified distributed electron cyclotron resonance ion source for the production of large diameter ion beams

    Microsoft Academic Search

    L. Wartski; Ph. Coste; C. Fusellier; C. Schwebel; J. Aubert

    2001-01-01

    The work presented in this article concerns the conception and the study of a multiantenna electron cyclotron resonance (ECR) ion source at 2.45 GHz dedicated to the surface treatment of large area materials. In this original device, a microwave plasma is created in a 20 cm in diameter ionization chamber. The 15 cm in diameter extracted ion beam has a

  3. Effect of resonant microwave power on a Penning ionization gauge ion source

    Microsoft Academic Search

    Ian G. Brown; James E. Galvin; Basil F. Gavin; Robert A. MacGill

    1985-01-01

    Microwave power resonant to the local electron cyclotron frequency has been coupled into the plasma discharge chamber of a hot-cathode PIG (Philips or Penning Ionization Gauge) ion source. The extracted ion beam was monitored for changes in characteristics of the beam with and without application of the microwave power. No change was seen in the ion charge state distribution. A

  4. Evaluation of surface damage on GaAs etched with an electron cyclotron resonance source

    Microsoft Academic Search

    K. K. Ko; S. W. Pang; T. Brock; M. W. Cole; L. M. Casas

    1994-01-01

    Surface damage induced by dry etching on GaAs with an electron cyclotron resonance source has been studied using both electrical measurements and surface analysis techniques. It is found that the unalloyed contact resistance extracted from the transmission lines is very sensitive to the etch-induced damage, and it increases significantly with ion energy and ion flux but decreases with etch temperature.

  5. 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

  6. 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...

  7. 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.

  8. Underground mineral extraction

    NASA Technical Reports Server (NTRS)

    Miller, C. G.; Stephens, J. B.

    1980-01-01

    A method was developed for extracting underground minerals such as coal, which avoids the need for sending personnel underground and which enables the mining of steeply pitched seams of the mineral. The method includes the use of a narrow vehicle which moves underground along the mineral seam and which is connected by pipes or hoses to water pumps at the surface of the Earth. The vehicle hydraulically drills pilot holes during its entrances into the seam, and then directs sideward jets at the seam during its withdrawal from each pilot hole to comminute the mineral surrounding the pilot hole and combine it with water into a slurry, so that the slurried mineral can flow to a location where a pump raises the slurry to the surface.

  9. An Extended Keyword Extraction Method

    NASA Astrophysics Data System (ADS)

    Hong, Bao; Zhen, Deng

    Among numerous Chinese keyword extraction methods, Chinese characteristics were shortly considered. This phenomenon going against the precision enhancement of the Chinese keyword extraction. An extended term frequency based method(Extended TF) is proposed in this paper which combined Chinese linguistic characteristics with basic TF method. Unary, binary and ternary grammars for the candidate keyword extraction as well as other linguistic features were all taken into account. The method establishes classification model using support vector machine. Tests show that the proposed extraction method improved key words precision and recall rate significantly. We applied the key words extracted by the extended TF method into the text file classification. Results show that the key words extracted by the proposed method contributed greatly to raising the precision of text file classification.

  10. Resonance affected scattering: Comparison of two hybrid methods involving filter diagonalization and the Lanczos method

    NASA Astrophysics Data System (ADS)

    McCormack, Drew A.; Kroes, Geert-Jan; Neuhauser, Daniel

    1998-10-01

    We apply two hybrid methods for solving scattering problems affected by resonances, to a four-dimensional reactive surface scattering system. In each method the solution of the problem is divided into two parts: a wave packet propagation, and a resonance calculation; results of the resonance calculation are used to extrapolate the long-time behavior of the system. In the first hybrid method, the propagation is by the multistep Chebyshev method, with calculation of resonances performed by the Lanczos method. In the second, the propagation is done using an implementation of the absorbing boundary condition (ABC) evolution operator, and the resonance calculation by filter diagonalization (FDG). Each method produces accurate scattering results in much less computation time than standard long-time wave packet propagation. The Chebyshev-Lanczos approach proves most capable for the calculation of resonances, but is computationally expensive. The ABC-FDG method is much cheaper to implement, but could not be made to extract accurate data for certain broad, overlapping resonances. This was overcome by propagating longer (still much shorter than for long-time propagation) to allow the elusive resonances time to decay.

  11. Experimental investigation of acoustic substrate losses in 1850-MHz thin film BAW resonators.

    PubMed

    Pensala, Tuomas; Thalhammer, Robert; Dekker, James; Kaitila, Jyrki

    2009-11-01

    After optimizing for electromechanical coupling coefficient K(2), the main performance improvement in the thin film bulk acoustic wave resonators and filters can be achieved by improving the Q value, i.e., minimizing the losses. In Bragg-reflector-based solidly mounted resonator technology, a significant improvement of Q has been achieved by optimizing the reflector not only for longitudinal wave, the intended operation mode, but also for shear waves. We have investigated the remaining acoustic radiation losses to the substrate in so-optimized 1850-MHz AlN resonators by removing the substrate underneath the resonators and comparing the devices with and without substrate by electrical characterization before and after the substrate removal. Several methods to extract Q-values of the resonators are compared. Changes caused by substrate removal are observed in resonator behavior, but no significant improvement in Q-values can be confirmed. Loss mechanisms other than substrate leakage are concluded to dominate the resonator Q-value. Difficulties of detecting small changes in the Q-values of the resonators are also discussed. PMID:19942540

  12. 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

  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. 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.

  15. Extraction chromatography: Progress and opportunities

    SciTech Connect

    Dietz, M.L.; Horwitz, E.P.; Bond, A.H. [Argonne National Lab., IL (United States). Chemistry Div.

    1997-10-01

    Extraction chromatography provides a simple and effective method for the analytical and preparative-scale separation of a variety of metal ions. Recent advances in extractant design, particularly the development of extractants capable of metal ion recognition or of strong complex formation in highly acidic media, have significantly improved the utility of the technique. Advances in support design, most notably the introduction of functionalized supports to enhance metal ion retention, promise to yield further improvements. Column instability remains a significant obstacle, however, to the process-scale application of extraction chromatography. 79 refs.

  16. Terminology Extraction from Log Files

    NASA Astrophysics Data System (ADS)

    Saneifar, Hassan; Bonniol, Stéphane; Laurent, Anne; Poncelet, Pascal; Roche, Mathieu

    The log files generated by digital systems can be used in management information systems as the source of important information on the condition of systems. However, log files are not exhaustively exploited in order to extract information. The classical methods of information extraction such as terminology extraction methods are irrelevant to this context because of the specific characteristics of log files like their heterogeneous structure, the special vocabulary and the fact that they do not respect a natural language grammar. In this paper, we introduce our approach Exterlog to extract the terminology from log files. We detail how it deals with the particularity of such textual data.

  17. Lasing from active optomechanical resonators

    PubMed Central

    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.

    2014-01-01

    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. PMID:25008784

  18. Astrophysics of resonant orbits in the Kerr metric

    NASA Astrophysics Data System (ADS)

    Brink, Jeandrew; Geyer, Marisa; Hinderer, Tanja

    2015-04-01

    This paper gives a complete characterization of the location of resonant orbits in a Kerr spacetime for all possible black hole spins and orbital parameter values. A resonant orbit in this work is defined as a geodesic for which the longitudinal and radial orbital frequencies are commensurate. Our analysis is based on expressing the resonance condition in its most symmetric form using Carlson's elliptic integrals, which enable us to provide exact results together with a number of concise formulas characterizing the explicit dependence on the system parameters. The locations of resonant orbits identify regions where intriguing observable phenomena could occur in astrophysical situations when various sources of perturbation act on the binary system. Resonant effects may have observable implications for the inspirals of compact objects into a supermassive black hole. During a generic inspiral the slowly evolving orbital frequencies will pass through a series of low-order resonances where the ratio of orbital frequencies is equal to the ratio of two small integers. At these locations rapid changes in the orbital parameters could produce a measurable phase shift in the emitted gravitational and electromagnetic radiation. Resonant orbits may also capture gas or larger objects leading to further observable characteristic electromagnetic emission. According to the Kolmogorov-Arnold-Moser theorem, low-order resonant orbits demarcate the regions where the onset of geodesic chaos could occur when the Kerr Hamiltonian is perturbed. Perturbations are induced for example if the spacetime of the central object is non-Kerr, if gravity is modified, if the orbiting particle has large multipole moments, or if additional masses are nearby. We find that the 1 /2 and 2 /3 resonances occur at approximately 4 and 5.4 Schwarzschild radii (Rs) from the black hole's event horizon. For compact object inspirals into supermassive black holes (˜106M? ) this region lies within the sensitivity band of space-based gravitational wave detectors such as eLISA. When interpreted within the context of the supermassive black hole at the Galactic center, Sgr A*, this implies that characteristic length scales of 41 ? as and 55 ? as and time scales of 50 min and 79 min respectively should be associated with resonant effects if Sgr A* is nonspinning, while spin decreases these values by up to ˜32 % and ˜28 %. These length scales are potentially resolvable with radio very-long-baseline interferometry measurements using the Event Horizon Telescope. We find that all low-order resonances are localized to the strong field region. In particular, for distances r >50 Rs from the black hole, the order of the resonances is sufficiently large that resonant effects of generic perturbations are not expected to lead to drastic changes in the dynamics. This fact guarantees the validity of using approximations based on averaging to model the orbital trajectory and frequency evolution of a test object in this region. Observing orbital motion in the intermediate region 50 Rsextracting the multipole moments of the central object by observing the orbit of a pulsar—since the object is close enough to be sensitive to the quadruple moment of the central object but far enough away not to be subjected to resonant effects.

  19. Beams in Resonators

    NASA Astrophysics Data System (ADS)

    Perrone, Maria Rita

    2004-08-01

    The evolution of the main parameters (spot size, radius of curvature, far-field divergence and/or beam quality factor) of laser radiation pulses propagating in stable and unstable cavities with variable reflectivity mirrors is investigated both theoretically and experimentally as a function of the number of round trips. It is shown that a theoretical analysis, formerly developed to study the growth of coherence of a Schell-Gauss model beam propagating through a periodic sequence of Gaussian apertures, provides a satisfactory description of the laser radiation temporal evolution. The study of transient states is very important in practice because high-gain, short-pulse lasers as excimers or copper-vapor lasers, generate pulses making only a few transits inside the resonator. In this situation, beam parameters seldom reach a steady state hence, an analysis yielding the beam parameters at each round-trip is needed for a better characterization of the laser beam quality and can be of great interest in many application fields. The experimental techniques used to analyze the temporal evolution of the main parameters of laser radiation pulses few ten of nanoseconds long are at first presented. Then, the propagation of laser radiation pulses in plane-parallel cavities with a variable reflectivity mirror is analyzed. Mirrors with Gaussian, super-Gaussian and step-reflectivity profile are tested in order to investigate the effects of the mirror reflectivity profile on the temporal evolution of the laser radiation parameters. Gaussian reflectivity mirrors of different spot size E are also considered to investigate the effect of E on the radiation beam-quality-factor evolution. An experimental study of coherence evolution versus the Fresnel number of Gaussian cavities is also presented. To this end, plane parallel cavities of different length and with a Gaussian reflectivity mirror have been applied to a XeCl excimer laser (?=308 nm) and the results on the resonator-length effects on the coherence growth of the laser radiation are presented. It is also shown that in Gaussian cavities of equal length and effective Fresnel number, the properties of the intracavity radiation are dependent on the Gaussian mirror distance from the active medium, since the onset of laser action. Finally, experimental and numerical results on the beam quality and coherence growth of the laser radiation in unstable cavities equipped with a variable reflectivity mirror as output coupler are presented. Variable reflectivity unstable cavities are generally applied to pulsed laser to get a faster coherence growth of the oscillating radiation. Note from Publisher: This article contains the abstract only.

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

    Microsoft Academic Search

    Jose A. Garde; Ramón Catalá; Rafael Gavara

    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

  1. 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

  2. Oil shale extraction using super-critical extraction

    NASA Technical Reports Server (NTRS)

    Compton, L. E. (inventor)

    1983-01-01

    Significant improvement in oil shale extraction under supercritical conditions is provided by extracting the shale at a temperature below 400 C, such as from about 250 C to about 350 C, with a solvent having a Hildebrand solubility parameter within 1 to 2 Hb of the solubility parameter for oil shale bitumen.

  3. 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

  4. 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.

  5. Heavy Z': resonant versus non-resonant searches

    E-print Network

    Guillaume Drieu La Rochelle; Martin Elmer

    2014-06-10

    Collider searches for new vector-like particles such as Z' have mostly been pursued by looking for a peak in the invariant mass spectrum of the decay products. However off-shell Z' exchange may leave an imprint on other kinematic distributions, leading thus to non-resonant searches. The aim of this paper is to assess, in the context of the LHC, the interplay between resonant (s-channel) and non-resonant (t-channel) searches for a generic leptophobic Z' model. We show in particular that while non-resonant searches are less sensitive to small couplings, they tend to be more adapted at high masses and large couplings. We discuss our findings both at the level of the current limits and the expectations at higher luminosities.

  6. Transmission resonances in the bipolar quantum resonant tunneling transistor

    E-print Network

    Mondragon, Antonio Richard

    1996-01-01

    ,rabolic dispersion relation. Calculations are done for model cases and compared to analytical results. The original and generalized methods are then applied to real world device potential profiles. In particular, the bipolar quantum resonant tunneling transistor (Bi...

  7. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, Paul H. (Los Alamos, NM); Brainard, James R. (Los Alamos, NM); Jarvinen, Gordon D. (Los Alamos, NM); Ryan, Robert R. (Los Alamos, NM)

    1997-01-01

    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.

  8. 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.

  9. 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.

  10. Multiple resonant railgun power supply

    DOEpatents

    Honig, Emanuel M. (Los Alamos, NM); Nunnally, William C. (Los Alamos, NM)

    1988-01-01

    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.

  11. 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.

  12. 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.

  13. 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.

  14. Broadband ferromagnetic resonance spectrometer

    NASA Astrophysics Data System (ADS)

    Denysenkov, V. P.; Grishin, A. M.

    2003-07-01

    The continuous wave ferromagnetic resonance (FMR) spectrometer operating in multioctave (0.05-40 GHz) frequency range has been built to investigate the magnetic properties of thin ferromagnetic films in the temperature range of 4-420 K. The spectrometer has two probeheads: one is the X-band microwave reflection cavity used to perform express room temperature measurements and the other is an in-cryostat microstrip line probe to carry out FMR experiments covering the entire frequency range offered by the microwave source. Very uniform and stable magnetic field up to 2.4 T, temperature 4 K-420 K, and continuous frequency scan performed by an HP8722D vector network analyzer provide various modes of operation. Both probe heads are equipped with two-circle high precision goniometers to ensure accurate characterization of magnetic anisotropy and magnetostatic waves spectra recording. Use of the phase sensitive detection, utilized by magnetic field modulation at audio frequency and computer triggering of the network analyzer, enables broadband spectrometer sensitivity to be as high as 1.3×1011 spins/Oe.

  15. 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.

  16. COMBINING NEUTRAL AND ACIDIC EXTRACTANTS FOR RECOVERING TRANSURANIC ELEMENTS FROM NUCLEAR FUEL

    SciTech Connect

    Lumetta, Gregg J.; Neiner, Doinita; Sinkov, Sergey I.; Carter, Jennifer C.; Braley, Jenifer C.; Latesky, Stanley; Gelis, Artem V.; Tkac, Peter; Vandegrift, George F.

    2011-10-03

    We have been investigating a solvent extraction system that combines a neutral extractant--octyl(phenyl)-N,N-diisobutyl-carbamoylmethylphosphine oxide (CMPO)--with an acidic extractant--bis(2-ethylhexyl)phosphoric acid (HDEHP)--to form a single process solvent for separating Am and Cm from the other components of irradiated nuclear fuel. It was originally hypothesized that the extraction chemistry of CMPO would dominate under conditions of high acidity (> 1 M HNO3), resulting in co-extraction of the transuranic and lanthanide elements into the organic phase. Contacting the loaded solvent with a solution of diethylenetriaminepentaacetate (DTPA) buffered with lactic or citric acid at pH {approx}3 to 4 would result in a condition in which the HDEHP chemistry dominates. Although the data somewhat support this hypothesis, it is clear that there are interactions between the two extractants such that they do not act independently in the extraction and stripping regimes. We report here studies directed at determining the nature and extent of interaction between CMPO and HDEHP, the synergistic behavior of CMPO and HDEHP in the extraction of americium and neodymium, and progress towards determining the thermodynamics of this extraction system. Neodymium and americium behave similarly in the combined solvent system, with a significant synergy between CMPO and HDEHP in the extraction of both of these trivalent elements from lactate-buffered DTPA solutions. In contrast, a much weaker synergistic behaviour is observed for europium. Thus, investigations into the fundamental chemistry involved in this system have focused on the neodymium extraction. The extraction of neodymium has been systematically investigated, individually varying the HDEHP concentration, the CMPO concentration, or the aqueous phase composition. Thermodynamic modeling of the neodymium extraction system has been initiated. Interactions between CMPO and HDEHP in the organic phase must be taken into account in the thermodynamic modeling; such interactions have been quantified by nuclear magnetic resonance measurements.

  17. 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

  18. 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.

  19. Nuclear magnetic resonance readable sensors

    E-print Network

    Ling, Yibo

    2010-01-01

    The monitoring of physiological biomarkers is fundamental to the diagnosis and treatment of disease. We describe here the development of molecular sensors which can be read by magnetic resonance (MR) relaxometry. MR is an ...

  20. Calligraphic Poling for WGM Resonators

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    By engineering the geometry of a nonlinear optical crystal, the effective efficiency of all nonlinear optical oscillations can be increased dramatically. Specifically, sphere and disk shaped crystal resonators have been used to demonstrate nonlinear optical oscillations at sub-milliwatt input power when cs light propagates in a Whispering Gallery Mode (WGM) of such a resonant cavity. in terms of both device production and experimentation in quantum optics, some nonlinear optical effects with naturally high efficiency can occult the desired nonlinear scattering process. the structure to the crystal resonator. In this paper, I will discuss a new method for generating poling structures in ferroelectric crystal resonators called calligraphic poling. The details of the poling apparatus, experimental results and speculation on future applications will be discussed.

  1. Resonant Mode-hopping Micromixing

    PubMed Central

    Jang, Ling-Sheng; Chao, Shih-Hui; Holl, Mark R.; Meldrum, Deirdre R.

    2009-01-01

    A common micromixer design strategy is to generate interleaved flow topologies to enhance diffusion. However, problems with these designs include complicated structures and dead volumes within the flow fields. We present an active micromixer using a resonating piezoceramic/silicon composite diaphragm to generate acoustic streaming flow topologies. Circulation patterns are observed experimentally and correlate to the resonant mode shapes of the diaphragm. The dead volumes in the flow field are eliminated by rapidly switching from one discrete resonant mode to another (i.e., resonant mode-hop). Mixer performance is characterized by mixing buffer with a fluorescence tracer containing fluorescein. Movies of the mixing process are analyzed by converting fluorescent images to two-dimensional fluorescein concentration distributions. The results demonstrate that mode-hopping operation rapidly homogenized chamber contents, circumventing diffusion-isolated zones. PMID:19551159

  2. Resonant tunneling through donor molecules

    Microsoft Academic Search

    A. K. Geim; T. J. Foster; A. Nogaret; N. Mori; P. J. McDonnell; N. La Scala Jr.; P. C. Main; L. Eaves

    1994-01-01

    We discuss the origin of zero-dimensional states, which give rise to resonant structure at the current onset in tunneling devices. The states can be identified as being due to random pairs of shallow donors.

  3. Magnetic Resonance Imaging (MRI): Brain

    MedlinePLUS

    KidsHealth > Parents > Doctors & Hospitals > Medical Tests & Exams > Magnetic Resonance Imaging (MRI): Brain Print A A A Text Size What's in this article? What It Is Why It's Done Preparation Procedure What ...

  4. Morphological resonances for multicomponent immunoassays

    SciTech Connect

    Whitten, W.B.; Shapiro, M.J.; Ramsey, J.M. [Chemical and Analytical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6142 (United States); Bronk, B.V. [United States Army Edgewood Research, Development and Engineering Center, Edgewood, Maryland 21010 (United States)

    1995-06-20

    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.

  5. Helium, its extraction and purification

    Microsoft Academic Search

    R. W. Wilson; H. R. Newson

    1967-01-01

    This is a general discussion of the extraction of helium from natural gas as practiced in the existing helium plants. Several phases of the helium extraction process, such as the refrigeration systems, and methods of carbon dioxide and water removal, are similar to those in natural gas processing. It is concluded that in cryogenic processes solid desiccants are more suited

  6. Supercritical multicomponent solvent coal extraction

    NASA Technical Reports Server (NTRS)

    Corcoran, W. H.; Fong, W. S.; Pichaichanarong, P.; Chan, P. C. F.; Lawson, D. D. (inventors)

    1983-01-01

    The yield of organic extract from the supercritical extraction of coal with larger diameter organic solvents such as toluene is increased by use of a minor amount of from 0.1 to 10% by weight of a second solvent such as methanol having a molecular diameter significantly smaller than the average pore diameter of the coal.

  7. Thromboplastic Activity of Placenta Extract

    Microsoft Academic Search

    Michael Finkelstein

    1945-01-01

    IN the course of an investigation of hormones of human placenta, we came across a substance which showed strong blood-coagulating properties. Freshwater extracts of placenta contain this factor. Their activity diminishes when they are kept at room temperature or in a refrigerator. It is not removed from the extracts by dialysis at 0° C. On filtration through a Seitz filter,

  8. 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.

  9. 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

  10. 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.

  11. Planetary distance law and resonance

    Microsoft Academic Search

    J. J. Rawal; Nehru Planetarium

    1989-01-01

    The relation between the planetary distance law and the resonant structures in the solar system and in the satellite systems\\u000a is shown, in that, the resonance relation has been expressed in terms of Roche’s (Bode’s) constant defined in the text. This\\u000a brings forth a coherent, elegant and unified picture of the formation and structure of the solar system and the

  12. Resonant ultrasonic attenuation in emulsions

    NASA Astrophysics Data System (ADS)

    Brunet, Thomas; Mascaro, Benoit; Poncelet, Olivier; Aristégui, Christophe; Raffy, Simon; Mondain-Monval, Olivier; Leng, Jacques

    2013-08-01

    We report the achievement of scattering resonant emulsions devoted to the frequency-control of acoustic attenuation in the megahertz range. By means of robotics, we produced highly monodisperse, in both size and shape, fluorinated-oil droplet suspensions, providing experimental evidence of several Mie scattering resonances. Ultrasonic experiments performed in such complex media are compared, with an excellent quantitative agreement, to theoretical predictions derived within the framework of the independent scattering approximation.

  13. Extraction of Questions Behind Messages

    NASA Astrophysics Data System (ADS)

    Matsumura, Naohiro; Kawahara, Daisuke; Okamoto, Masashi; Kurohashi, Sadao; Nishida, Toyoaki

    To overcome the limitation of conventional text-mining approaches in which frequent patterns of word occurrences are to be extracted to understand obvious user needs, this paper proposes an approach to extracting questions behind messages to understand potential user needs. We first extract characteristic case frames by comparing the case frames constructed from target messages with the ones from 25M sentences in the Web and 20M sentences in newspaper articles of 20 years. Then we extract questions behind messages by transforming the characteristic case frames into interrogative sentences based on new information and old information, i.e., replacing new information with WH-question words. The proposed approach is, in other words, a kind of classification of word occurrence pattern. Qualitative evaluations of our preliminary experiments suggest that extracted questions show problem consciousness and alternative solutions -- all of which help to understand potential user needs.

  14. P-wave resonant state of the He4? hypernucleus in the 4He (K- ,?-) reaction

    NASA Astrophysics Data System (ADS)

    Harada, Toru; Hirabayashi, Yoshiharu

    2015-01-01

    We theoretically investigate a possible existence of a p-wave He4? resonant state with J? =1-, T ? 1 / 2 above the ? threshold, using a coupled (3 N- ?) + (3 N- ?) model with a spreading potential. We calculate inclusive and ?-? conversion ?- spectra in a 4He (K- ,?-) reaction at 1.5 GeV/c, ?lab = 4- 12 ° by the Green's function method in a distorted-wave impulse approximation. The pole position for the p-wave ? resonant state in He4? is determined on the Riemann sheets in the complex E plane. The result shows that a peak of the He4? resonant state is clearly obtained in the conversion spectra above the ? threshold, and that the angular distributions of these spectra enable extraction of the contribution of the resonant state from the ?- spectra. Effects of the ?-nucleus potential and the interference between ? and ? on the spectra are also discussed.

  15. Coupling of a locally implanted rare-earth ion ensemble to a superconducting micro-resonator

    SciTech Connect

    Wisby, I., E-mail: ilana.wisby@npl.co.uk; Tzalenchuk, A. Ya. [National Physical Laboratory, Hampton Road, Teddington TW11 0LW (United Kingdom); Royal Holloway, University of London, Egham TW20 0EX (United Kingdom); Graaf, S. E. de; Adamyan, A.; Kubatkin, S. E. [Department of Microtechnology and Nanoscience, MC2, Chalmers University of Technology, SE-41296, Gothenburg (Sweden); Gwilliam, R. [Advanced Technology Institute, Faculty of Electronics and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Meeson, P. J. [Royal Holloway, University of London, Egham TW20 0EX (United Kingdom); Lindström, T. [National Physical Laboratory, Hampton Road, Teddington TW11 0LW (United Kingdom)

    2014-09-08

    We demonstrate the coupling of rare-earth ions locally implanted in a substrate (Gd{sup 3+} in Al{sub 2}O{sub 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{sup 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.

  16. Resonances in coupled ?K,?K scattering from quantum chromodynamics

    E-print Network

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

    2014-10-23

    Using first-principles calculation within Quantum Chromodynamics, we are able to determine a pattern of strangeness=1 resonances which appear as complex singularities within coupled $\\pi K$, $\\eta K$ scattering amplitudes. We make use of numerical computation in the lattice discretized approach to the quantum field theory with light quark masses corresponding to $m_\\pi \\sim 400\\, \\textrm{MeV}$ and at a single lattice spacing. The energy dependence of scattering amplitudes is extracted through their relationship to the discrete spectrum in a finite-volume, which we map out in unprecedented detail.

  17. Resonances in coupled ?K-?K scattering from quantum chromodynamics.

    PubMed

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

    2014-10-31

    Using a first-principles calculation within quantum chromodynamics, we are able to determine a pattern of strangeness=1 resonances that appear as complex singularities within coupled ?K-?K scattering amplitudes. We make use of numerical computation in the lattice discretized approach to the quantum field theory with light quark masses corresponding to m(?)?400??MeV and at a single lattice spacing. The energy dependence of scattering amplitudes is extracted through their relationship to the discrete spectrum in a finite volume, which we map out in unprecedented detail. PMID:25396360

  18. 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.

  19. Comparison of Automated Nucleic Acid Extraction Methods with Manual Extraction

    PubMed Central

    Dundas, Nicola; Leos, N. Kristine; Mitui, Midori; Revell, Paula; Rogers, Beverly Barton

    2008-01-01

    Automated nucleic acid extractors can improve workflow and decrease variability in the clinical laboratory. We evaluated Qiagen EZ1 (Valencia, CA) and bioMérieux (Durham, NC) easyMAG extractors compared with Qiagen manual extraction using targets and matrices commonly available in the clinical laboratory. Pooled samples were spiked with various organisms, serially diluted, and extracted in duplicate. The organisms/matrices were Bordetella pertussis/bronchoalveolar lavage, herpes simplex virus II/cerebrospinal fluid, coxsackievirus A9/cerebrospinal fluid, BK virus/plasma, and Mycoplasma pneumoniae/endotracheal tube samples. Extracts were amplified in duplicate using real-time PCR assays, and amplification of the target at a cycle threshold of 35 using the manual method was used for comparison. Amplification efficiency of nucleic acids extracted by automated methods was similar to that by the manual method except for a loss of efficiency for M. pneumoniae in endotracheal tube samples. The EZ1 viral kit 2.0 gave better results for coxsackievirus A9 than the EZ1 viral kit version 1.0. At the lowest limit of detection (past a cycle threshold of 35), the easyMAG was more likely to produce amplifiable nucleic acid than were either the EZ1 or manual extraction. Operational complexity, defined as the number of manipulations required to obtain an extracted sample, was the lowest for the easyMAG. The easyMAG was the most expensive of the methods, followed by the EZ1 kit and manual extraction. PMID:18556770

  20. Empathy in schizophrenia: impaired resonance.

    PubMed

    Haker, Helene; Rössler, Wulf

    2009-09-01

    Resonance is the phenomenon of one person unconsciously mirroring the motor actions as basis of emotional expressions of another person. This shared representation serves as a basis for sharing physiological and emotional states of others and is an important component of empathy. Contagious laughing and contagious yawning are examples of resonance. In the interpersonal contact with individuals with schizophrenia we can often experience impaired empathic resonance. The aim of this study is to determine differences in empathic resonance-in terms of contagion by yawning and laughing-in individuals with schizophrenia and healthy controls in the context of psychopathology and social functioning. We presented video sequences of yawning, laughing or neutral faces to 43 schizophrenia outpatients and 45 sex- and age-matched healthy controls. Participants were video-taped during the stimulation and rated regarding contagion by yawning and laughing. In addition, we assessed self-rated empathic abilities (Interpersonal Reactivity Index), psychopathology (Positive and Negative Syndrome Scale in the schizophrenia group resp. Schizotypal Personality Questionnaire in the control group), social dysfunction (Social Dysfunction Index) and executive functions (Stroop, Fluency). Individuals with schizophrenia showed lower contagion rates for yawning and laughing. Self-rated empathic concern showed no group difference and did not correlate with contagion. Low rate of contagion by laughing correlated with the schizophrenia negative syndrome and with social dysfunction. We conclude that impaired resonance is a handicap for individuals with schizophrenia in social life. Blunted observable resonance does not necessarily reflect reduced subjective empathic concern. PMID:19377866

  1. Micro-machined resonator oscillator

    DOEpatents

    Koehler, Dale R. (Albuquerque, NM); Sniegowski, Jeffry J. (Albuquerque, NM); Bivens, Hugh M. (Albuquerque, NM); Wessendorf, Kurt O. (Albuquerque, NM)

    1994-01-01

    A micro-miniature resonator-oscillator is disclosed. Due to the miniaturization of the resonator-oscillator, oscillation frequencies of one MHz and higher are utilized. A thickness-mode quartz resonator housed in a micro-machined silicon package and operated as a "telemetered sensor beacon" that is, a digital, self-powered, remote, parameter measuring-transmitter in the FM-band. The resonator design uses trapped energy principles and temperature dependence methodology through crystal orientation control, with operation in the 20-100 MHz range. High volume batch-processing manufacturing is utilized, with package and resonator assembly at the wafer level. Unique design features include squeeze-film damping for robust vibration and shock performance, capacitive coupling through micro-machined diaphragms allowing resonator excitation at the package exterior, circuit integration and extremely small (0.1 in. square) dimensioning. A family of micro-miniature sensor beacons is also disclosed with widespread applications as bio-medical sensors, vehicle status monitors and high-volume animal identification and health sensors. The sensor family allows measurement of temperatures, chemicals, acceleration and pressure. A microphone and clock realization is also available.

  2. Micro-machined resonator oscillator

    DOEpatents

    Koehler, D.R.; Sniegowski, J.J.; Bivens, H.M.; Wessendorf, K.O.

    1994-08-16

    A micro-miniature resonator-oscillator is disclosed. Due to the miniaturization of the resonator-oscillator, oscillation frequencies of one MHz and higher are utilized. A thickness-mode quartz resonator housed in a micro-machined silicon package and operated as a telemetered sensor beacon'' that is, a digital, self-powered, remote, parameter measuring-transmitter in the FM-band. The resonator design uses trapped energy principles and temperature dependence methodology through crystal orientation control, with operation in the 20--100 MHz range. High volume batch-processing manufacturing is utilized, with package and resonator assembly at the wafer level. Unique design features include squeeze-film damping for robust vibration and shock performance, capacitive coupling through micro-machined diaphragms allowing resonator excitation at the package exterior, circuit integration and extremely small (0.1 in. square) dimensioning. A family of micro-miniature sensor beacons is also disclosed with widespread applications as bio-medical sensors, vehicle status monitors and high-volume animal identification and health sensors. The sensor family allows measurement of temperatures, chemicals, acceleration and pressure. A microphone and clock realization is also available. 21 figs.

  3. Stochastic resonance with matched filtering

    E-print Network

    Li-Fang Li; Jian-Yang Zhu

    2010-06-28

    Along with the development of interferometric gravitational wave detector, we enter into an epoch of gravitational wave astronomy, which will open a brand new window for astrophysics to observe our universe. Almost all of the data analysis methods in gravitational wave detection are based on matched filtering. Gravitational wave detection is a typical example of weak signal detection, and this weak signal is buried in strong instrument noise. So it seems attractable if we can take advantage of stochastic resonance. But unfortunately, almost all of the stochastic resonance theory is based on Fourier transformation and has no relation to matched filtering. In this paper we try to relate stochastic resonance to matched filtering. Our results show that stochastic resonance can indeed be combined with matched filtering for both periodic and non-periodic input signal. This encouraging result will be the first step to apply stochastic resonance to matched filtering in gravitational wave detection. In addition, based on matched filtering, we firstly proposed a novel measurement method for stochastic resonance which is valid for both periodic and non-periodic driven signal.

  4. Lasing from active optomechanical resonators.

    PubMed

    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

    2014-01-01

    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. PMID:25008784

  5. Universal formalism of Fano resonance

    NASA Astrophysics Data System (ADS)

    Huang, Liang; Lai, Ying-Cheng; Luo, Hong-Gang; Grebogi, Celso

    2015-01-01

    The phenomenon of Fano resonance is ubiquitous in a large variety of wave scattering systems, where the resonance profile is typically asymmetric. Whether the parameter characterizing the asymmetry should be complex or real is an issue of great experimental interest. Using coherent quantum transport as a paradigm and taking into account of the collective contribution from all available scattering channels, we derive a universal formula for the Fano-resonance profile. We show that our formula bridges naturally the traditional Fano formulas with complex and real asymmetry parameters, indicating that the two types of formulas are fundamentally equivalent (except for an offset). The connection also reveals a clear footprint for the conductance resonance during a dephasing process. Therefore, the emergence of complex asymmetric parameter when fitting with experimental data needs to be properly interpreted. Furthermore, we have provided a theory for the width of the resonance, which relates explicitly the width to the degree of localization of the close-by eigenstates and the corresponding coupling matrices or the self-energies caused by the leads. Our work not only resolves the issue about the nature of the asymmetry parameter, but also provides deeper physical insights into the origin of Fano resonance. Since the only assumption in our treatment is that the transport can be described by the Green's function formalism, our results are also valid for broad disciplines including scattering problems of electromagnetic waves, acoustics, and seismology.

  6. The Effects of Extracts Obtained by Supercritical Fluid Extraction and Traditional Extraction Techniques on Larvae Leptinotarsa decemlineata SAY

    Microsoft Academic Search

    Roman Pavela; Marie Sajfrtová; Helena Sovová; Jind?ich Karban; Martin Bárnet

    2009-01-01

    Extracts from savory (Satureja hortensis L.) and thymus (Thymus vulgaris L.) were obtained by supercritical fluid extraction, hydrodistillation, and Soxhlet extraction with benzene and ethanol. The composition of volatile compounds in the extracts was determined by gas chromatography, and the toxicity and antifeedant effects of the extracts on larvae of Colorado potato beetle were evaluated.Generally it is possible to claim

  7. Cardiovascular Magnetic Resonance Imaging

    NASA Astrophysics Data System (ADS)

    Pelc, Norbert

    2000-03-01

    Cardiovascular diseases are a major source of morbidity and mortality in the United States. Early detection of disease can often be used to improved outcomes, either through direct interventions (e.g. surgical corrections) or by causing the patient to modify his or her behavior (e.g. smoking cessation or dietary changes). Ideally, the detection process should be noninvasive (i.e. it should not be associated with significant risk). Magnetic Resonance Imaging (MRI) refers to the formation of images by localizing NMR signals, typically from protons in the body. As in other applications of NMR, a homogeneous static magnetic field ( ~0.5 to 4 T) is used to create ``longitudinal" magnetization. A magnetic field rotating at the Larmor frequency (proportional to the static field) excites spins, converting longitudinal magnetization to ``transverse" magnetization and generating a signal. Localization is performed using pulsed gradients in the static field. MRI can produce images of 2-D slices, 3-D volumes, time-resolved images of pseudo-periodic phenomena such as heart function, and even real-time imaging. It is also possible to acquire spatially localized NMR spectra. MRI has a number of advantages, but perhaps the most fundamental is the richness of the contrast mechanisms. Tissues can be differentiated by differences in proton density, NMR properties, and even flow or motion. We also have the ability to introduce substances that alter NMR signals. These contrast agents can be used to enhance vascular structures and measure perfusion. Cardiovascular MRI allows the reliable diagnosis of important conditions. It is possible to image the blood vessel tree, quantitate flow and perfusion, and image cardiac contraction. Fundamentally, the power of MRI as a diagnostic tool stems from the richness of the contrast mechanisms and the flexibility in control of imaging parameters.

  8. Applied Magnetic Resonance ISSN 0937-9347

    E-print Network

    1 23 Applied Magnetic Resonance ISSN 0937-9347 Volume 42 Number 3 Appl Magn Reson (2012) 42:353-361 DOI 10.1007/s00723-011-0298-1 Transverse Relaxation of Scalar Coupled Protons in Magnetic Resonance Relaxation of Scalar Coupled Protons in Magnetic Resonance of Non-Deuterated Proteins Takuya F. Segawa

  9. Theory of Deformed Fabry Perot Resonator

    Microsoft Academic Search

    Hisanao Ogura; Yasuo Yoshida; Jun-ichi Ikenoue

    1965-01-01

    On the basis of the cavity picture of Fabry Perot resonator which we have developed previously, a theory of deformed resonator is presented, and applied to the circular Fabry Perot resonators with a tilted mirror and a curved mirror. The loss of the resonator is expressed as the imaginary part of the diagonal element of the radiative perturbation matrix, in

  10. Tuned Spiral Resonators for Composite Metamaterials

    Microsoft Academic Search

    M. Faisal Khan; M. Junaid Mughal

    2006-01-01

    Metamaterials composed of thin wires and spiral resonators have been studied in this paper. Technique to tune spiral resonators have been proposed. Transmission and reflection properties of metamaterials composed of thin wires and tuned spiral resonators have been simulated and compared with conventional metamaterials. The center frequency and transmission bandwidth of metamaterials have been varied through tuning of spiral resonators

  11. Graded-index whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor); Ilchenko, Vladimir (Inventor); Matsko, Andrey B. (Inventor)

    2005-01-01

    Whispering gallery mode optical resonators which have spatially-graded refractive indices. In one implementation, the refractive index spatially increases with a distance from an exterior surface of such a resonator towards an interior of the resonator to produce substantially equal spectral separations for different whispering gallery modes. An optical coupler may be used with such a resonator to provide proper optical coupling.

  12. A Novel Miniature ZT-Cut Resonator

    Microsoft Academic Search

    J. W. Hermann

    1985-01-01

    A novel miniature ZT-cut resonator is described. It consists of a vibrational section, composed of two resonant plates connected by a resonant arm, and of a supporting section. The latter includes a clamping area where movement and stresses are evanescent, so that the crystal can be glued with epoxy onto a tiny pedestal. Quartz wafers, comprising several tens of resonators,

  13. Bayesian Optimization of Magnetic Resonance Imaging Sequences

    E-print Network

    Seeger, Matthias

    Bayesian Optimization of Magnetic Resonance Imaging Sequences Matthias Seeger MMCI Cluster SAARLANDES Seeger (MMCI) Bayesian MRI Optimization 28 November 2008 1 / 19 #12;Outline 1 Magnetic Resonance) Bayesian MRI Optimization 28 November 2008 2 / 19 #12;Magnetic Resonance Imaging Magnetic Resonance Imaging

  14. 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.

  15. 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.

  16. Ferromagnetic resonance imaging of Co films using magnetic resonance force microscopy

    E-print Network

    Hammel, P. Chris

    Ferromagnetic resonance imaging of Co films using magnetic resonance force microscopy B. J. Suh, P of microscopic ferromagnetic resonance FMR detected using the magnetic resonance force microscope MRFM of structural and magnetic properties of materials. The mag- netic resonance force microscope MRFM can

  17. Sensitivity and spatial resolution for electron-spin-resonance detection by magnetic resonance force microscopy

    E-print Network

    Hammel, P. Chris

    Sensitivity and spatial resolution for electron-spin-resonance detection by magnetic resonance The signal intensity of electron spin resonance in magnetic resonance force microscopy MRFM experiments that magnetic resonance force microscopy MRFM is a new 3D imaging technique8,9 with the potential of achieving

  18. Wirelessly sensing resonant frequency of passive resonators with different Q factors

    Microsoft Academic Search

    Mathew Lukacs; Xinhua Ren; Xun Gong

    2011-01-01

    This paper presents a method of wirelessly sensing the resonant frequency of passive resonators using modulated waveforms. A pulse signal with a relatively wide frequency spectrum is transmitted towards a passive resonator, which in turn, reflects energy back to the interrogator. After time-domain gating and processing, the resonant frequency of the passive resonator can be wireless detected. This technique can

  19. Optimized brain extraction for pathological brains (optiBET).

    PubMed

    Lutkenhoff, Evan S; Rosenberg, Matthew; Chiang, Jeffrey; Zhang, Kunyu; Pickard, John D; Owen, Adrian M; Monti, Martin M

    2014-01-01

    The study of structural and functional magnetic resonance imaging data has greatly benefitted from the development of sophisticated and efficient algorithms aimed at automating and optimizing the analysis of brain data. We address, in the context of the segmentation of brain from non-brain tissue (i.e., brain extraction, also known as skull-stripping), the tension between the increased theoretical and clinical interest in patient data, and the difficulty of conventional algorithms to function optimally in the presence of gross brain pathology. Indeed, because of the reliance of many algorithms on priors derived from healthy volunteers, images with gross pathology can severely affect their ability to correctly trace the boundaries between brain and non-brain tissue, potentially biasing subsequent analysis. We describe and make available an optimized brain extraction script for the pathological brain (optiBET) robust to the presence of pathology. Rather than attempting to trace the boundary between tissues, optiBET performs brain extraction by (i) calculating an initial approximate brain extraction; (ii) employing linear and non-linear registration to project the approximate extraction into the MNI template space; (iii) back-projecting a standard brain-only mask from template space to the subject's original space; and (iv) employing the back-projected brain-only mask to mask-out non-brain tissue. The script results in up to 94% improvement of the quality of extractions over those obtained with conventional software across a large set of severely pathological brains. Since optiBET makes use of freely available algorithms included in FSL, it should be readily employable by anyone having access to such tools. PMID:25514672

  20. Optimized Brain Extraction for Pathological Brains (optiBET)

    PubMed Central

    Lutkenhoff, Evan S.; Rosenberg, Matthew; Chiang, Jeffrey; Zhang, Kunyu; Pickard, John D.; Owen, Adrian M.; Monti, Martin M.

    2014-01-01

    The study of structural and functional magnetic resonance imaging data has greatly benefitted from the development of sophisticated and efficient algorithms aimed at automating and optimizing the analysis of brain data. We address, in the context of the segmentation of brain from non-brain tissue (i.e., brain extraction, also known as skull-stripping), the tension between the increased theoretical and clinical interest in patient data, and the difficulty of conventional algorithms to function optimally in the presence of gross brain pathology. Indeed, because of the reliance of many algorithms on priors derived from healthy volunteers, images with gross pathology can severely affect their ability to correctly trace the boundaries between brain and non-brain tissue, potentially biasing subsequent analysis. We describe and make available an optimized brain extraction script for the pathological brain (optiBET) robust to the presence of pathology. Rather than attempting to trace the boundary between tissues, optiBET performs brain extraction by (i) calculating an initial approximate brain extraction; (ii) employing linear and non-linear registration to project the approximate extraction into the MNI template space; (iii) back-projecting a standard brain-only mask from template space to the subject’s original space; and (iv) employing the back-projected brain-only mask to mask-out non-brain tissue. The script results in up to 94% improvement of the quality of extractions over those obtained with conventional software across a large set of severely pathological brains. Since optiBET makes use of freely available algorithms included in FSL, it should be readily employable by anyone having access to such tools. PMID:25514672

  1. 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.

  2. 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

  3. Evaluation of DNA and RNA Extraction Methods

    Microsoft Academic Search

    C S Edwin Shiaw; M S Shiran; Y K Cheah; G C Tan; A R Sabariah; M Path

    2010-01-01

    SUMMARY This study was done to evaluate various DNA and RNA extractions from archival FFPE tissues. A total of 30 FFPE blocks from the years of 2004 to 2006 were assessed with each modified and adapted method. Extraction protocols evaluated include the modified enzymatic extraction method (Method A), Chelex-100 extraction method (Method B), heat-induced retrieval in alkaline solution extraction method

  4. 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.

  5. Experimental study of resonant states in 27P via elastic scattering of 26Si+p

    NASA Astrophysics Data System (ADS)

    Jung, H. S.; Lee, C. S.; Kwon, Y. K.; Moon, J. Y.; Lee, J. H.; Yun, C. C.; Kubono, S.; Yamaguchi, H.; Hashimoto, T.; Kahl, D.; Hayakawa, S.; Choi, Seonho; Kim, M. J.; Kim, Y. H.; Kim, Y. K.; Park, J. S.; Kim, E. J.; Moon, C.-B.; Teranishi, T.; Wakabayashi, Y.; Iwasa, N.; Yamada, T.; Togano, Y.; Kato, S.; Cherubini, S.; Rapisarda, G. G.

    2012-04-01

    Proton resonant states in 27P were studied by the resonant elastic scattering of 26Si+p with a 26Si radioactive ion beam bombarding a thick H2 gas target with the inverse kinematics method. The properties of these resonance states are important to better constrain the production rates of the 26Si(p,?)27P reaction. This is one of the astrophysically important reactions needed to understand proton-rich nucleosynthesis such as the galactic production of 26Al and energy generation in explosive stellar environments. Although there are recent studies on the resonant structure in 27P, large uncertainties remain, and only a few levels are known. In this work, resonant states were observed over the excitation energies range of 2.3 to 3.8 MeV with high statistics and without background contamination within the target. The resonance parameters were extracted by an R-matrix analysis of the excitation function. The 26Si(p,?)27P stellar reaction rate has been evaluated, including high-lying resonances found in this work.

  6. 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

  7. Microbead-assisted high resolution microwave planar ring resonator for organic-vapor sensing

    NASA Astrophysics Data System (ADS)

    Zarifi, Mohammad H.; Fayaz, Mohammadreza; Goldthorp, Jordan; Abdolrazzaghi, Mohammad; Hashisho, Zaher; Daneshmand, Mojgan

    2015-02-01

    A microbead-assisted planar microwave resonator for organic vapor sensing applications is presented. The core of this sensor is a planar microstrip split-ring resonator, integrated with an active feedback loop to enhance the initial quality factor from 200 to ˜1 M at an operational resonance frequency of 1.42 GHz. Two different types of microbeads, beaded activated carbon (BAC) and polymer based (V503) beads, are investigated in non-contact mode for use as gas adsorbents in the gas sensing device. 2-Butoxyethanol (BE) is used in various concentrations as the target gas, and the transmitted power (S21) of the two port resonator is measured. The two main microwave parameters of resonance frequency and quality factor are extracted from S21 since these parameters are less susceptible to environmental and instrumental noise than the amplitude. Measured results demonstrate a minimum resonance frequency shift of 10 kHz for a 35 ppm concentration of BE exposure to carbon beads and 160 kHz for the polymer based adsorbent at the same concentration. The quality factor of the resonator also changed for different concentrations, but a distinguishable variation is observed for the BAC adsorbents. The high quality factor of the sensor provides the opportunity of real time monitoring of the adsorbent behaviors in remote sensing mode with very high resolution.

  8. Air-assisted solvent extraction: towards a novel extraction process

    Microsoft Academic Search

    H. M. Tarkan; J. A. Finch

    2005-01-01

    The air-assisted solvent extraction (AASX) concept uses a solvent-coated bubble to contact the organic and aqueous phases. Compared to conventional solvent extraction, a high contact area can be created using less solvent and the natural buoyancy provided by the air core promotes phase separation. A method of producing coated bubbles exploiting foaming properties of kerosene-based solvent is introduced. Coating thickness

  9. 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

  10. Entity extraction via ensemble semantics

    E-print Network

    Marco Pennacchiotti; Patrick Pantel

    2009-01-01

    Combining information extraction systems yields significantly higher quality resources than each system in isolation. In this paper, we generalize such a mixing of sources and features in a framework called Ensemble Semantics. We show very large gains in entity extraction by combining state-of-the-art distributional and patternbased systems with a large set of features from a webcrawl, query logs, and Wikipedia. Experimental results on a webscale extraction of actors, athletes and musicians show significantly higher mean average precision scores (29 % gain) compared with the current state of the art. 1

  11. 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.

  12. Resonances in retrograde circumbinary discs

    NASA Astrophysics Data System (ADS)

    Nixon, Chris; Lubow, Stephen H.

    2015-04-01

    We analyse the interaction of an eccentric binary with a circular coplanar circumbinary disc that rotates in a retrograde sense with respect to the binary. In the circular binary case, no Lindblad resonances lie within the disc and no Lindblad resonant torques are produced, as was previously known. By analytic means, we show that when the binary orbit is eccentric, there exist components of the gravitational potential of the binary which rotate in a retrograde sense to the binary orbit and so rotate progradely with respect to this disc, allowing a resonant interaction to occur between the binary and the disc. The resulting resonant torques distinctly alter the disc response from the circular binary case. We describe results of three-dimensional hydrodynamic simulations to explore this effect and categorize the response of the disc in terms of modes whose strengths vary as a function of binary mass ratio and eccentricity. These mode strengths are weak compared to the largest mode strengths expected in the prograde case where the binary and disc rotate in the same sense. However, for sufficiently high binary eccentricity, resonant torques open a gap in a retrograde circumbinary disc, while permitting gas inflow on to the binary via gas streams. The inflow results in a time varying accretion rate on to the binary that is modulated over the binary orbital period, as was previously found to occur in the prograde case.

  13. Matryoshka locally resonant sonic crystal.

    PubMed

    Elford, Daniel P; Chalmers, Luke; Kusmartsev, Feodor V; Swallowe, Gerry M

    2011-11-01

    The results of numerical modeling of sonic crystals with resonant array elements are reported. The investigated resonant elements include plain slotted cylinders as well as their various combinations, in particular, Russian doll or Matryoshka configurations. The acoustic band structure and transmission characteristics of such systems have been computed with the use of finite element methods. The general concept of a locally resonant sonic crystal is proposed that utilizes acoustic resonances to form additional band gaps that are decoupled from Bragg gaps. An existence of a separate attenuation mechanism associated with the resonant elements that increases performance in the lower frequency regime has been identified. The results show a formation of broad band gaps positioned significantly below the first Bragg frequency. For low frequency broadband attenuation, a most optimal configuration is the Matryoshka sonic crystal, where each scattering unit is composed of multiple concentric slotted cylinders. This system forms numerous gaps in the lower frequency regime, below Bragg bands, while maintaining a reduced crystal size viable for noise barrier technology. The finding opens alternative perspectives for the construction of sound barriers in the low frequency range usually inaccessible by traditional means including conventional sonic crystals. PMID:22087903

  14. Defect-mediated resonance shift of silicon-on-insulator racetrack resonators

    E-print Network

    Bowers, John

    Defect-mediated resonance shift of silicon-on- insulator racetrack resonators J. J. Ackert,1, * J of Silicon-On-Insulator (SOI) racetrack resonators. Selective ion implantation was used to create deep

  15. 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

  16. 21 CFR 73.1030 - Annatto extract.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Annatto extract. 73.1030 Section 73...CERTIFICATION Drugs § 73.1030 Annatto extract. (a) Identity and specifications. (1) The color additive annatto extract shall conform in...

  17. Comparing extractions of Sivers functions

    E-print Network

    M. Anselmino; M. Boglione; J. C. Collins; U. D'Alesio; A. V. Efremov; K. Goeke; A. Kotzinian; S. Menzel; A. Metz; F. Murgia; A. Prokudin; P. Schweitzer; W. Vogelsang; F. Yuan

    2005-11-02

    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.

  18. Extracting Oil From Tar Sands

    NASA Technical Reports Server (NTRS)

    Ford, L. B.; Daly, D.

    1984-01-01

    Recovery of oil from tar sands possible by batch process, using steam produced by solar heater. In extraction process, solar heater provides steam for heating solvent boiler. Boiling solvent removes oil from tar sands in Soxhlet extractor.

  19. Liquid-Liquid Extraction Processes

    E-print Network

    Fair, J. R.; Humphrey, J. L.

    1983-01-01

    Liquid-liquid extraction is the separation of one or more components of a liquid solution by contact with a second immiscible liquid called the solvent. If the components in the original liquid solution distribute themselves differently between...

  20. 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).

  1. Cartographic Feature Extraction George Vosselman

    E-print Network

    Vosselman, George

    of the stereo image pair. After this determination the 3D cursor snaps to the local terrain surface. ThusCartographic Feature Extraction George Vosselman Delft University of Technology Faculty of Civil

  2. 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 ...

  3. Electronic transmittance phase extracted from mesoscopic interferometers

    PubMed Central

    2012-01-01

    The usual experimental set-up for measuring the wave function phase shift of electrons tunneling through a quantum dot (QD) embedded in a ring (i.e., the transmittance phase) is the so-called ‘open’ interferometer as first proposed by Schuster et al. in 1997, in which the electrons back-scattered at source and the drain contacts are absorbed by additional leads in order to exclude multiple interference. While in this case one can conveniently use a simple two-path interference formula to extract the QD transmittance phase, the open interferometer has also a number of draw-backs, such as a reduced signal and some uncertainty regarding the effects of the extra leads. Here we present a meaningful theoretical study of the QD transmittance phase in ‘closed’ interferometers (i.e., connected only to source and drain leads). By putting together data from existing literature and giving some new proofs, we show both analytically and by numerical simulations that the existence of phase lapses between consecutive resonances of the ‘bare’ QD is related to the signs of the corresponding Fano parameters - of the QD + ring system. More precisely, if the Fano parameters have the same sign, the transmittance phase of the QD exhibits a ? lapse. Therefore, closed mesoscopic interferometers can be used to address the ‘universal phase lapse’ problem. Moreover, the data from already existing Fano interference experiments from Kobayashi et al. in 2003 can be used to infer the phase lapses. PMID:23061877

  4. Multimembrane bioreactor for extractive fermentation

    SciTech Connect

    Cho, T.; Shuler, M.L.

    1986-03-01

    A multimembrane reactor is described. Four layers (gas, cells, nutrient, and solvent) are separated by membranes. This structure prevents solvent emulsification in the fermentation broth. The system was tested for ethyl alcohol production from glucose using yeast. Tributyl phosphate (TBP) was chosen as the extractant. Experiments demonstrate for the first time a successful extractive fermentation with a practical solvent. Prevention of emulsification removes the toxic effect of TBP on yeast metabolism. (Refs. 29).

  5. Hot water bitumen extraction process

    SciTech Connect

    Rendall, J.S.

    1989-10-24

    This patent describes a method of extracting bitumen oils from tar-sands ore. It includes an initial conditioning step comprising crushing tar-sands ore to yield solid particles of a maximum size required by a log washer conditioner in a second conditioning step; a bitumen extraction step; a bitumen separation step; a solvent recovery step; a sand washing and water clarification step; and a sand solvent recovery step.

  6. Lima Bean Bacteria DNA Extraction

    NSDL National Science Digital Library

    Lana Hays

    2009-01-01

    This laboratory exercise is designed to show learners how DNA can easily be extracted from lima bean bacteria. This experiment requires the use of a centrifuge (not included in cost of materials). Use this experiment to supplement any unit on genetics and to demonstrate how scientists study DNA. Adult supervision is recommended. This resource guide includes tips and suggestions for instructors as well as other DNA extraction experiments and a chart for learners to answer questions.

  7. Giant resonances: Progress, new directions, new challenges

    SciTech Connect

    Bertrand, J.R.; Beene, J.R.

    1989-01-01

    A review of some recent developments in the field of giant multipole resonances is presented. Particular emphasis is placed on directions that the authors feel will be followed in this field during the next several years. In particular, the use of high-energy heavy ions to excite the giant resonances is shown to provide exciting new capabilities for giant resonance studies. Among subjects covered are: Coulomb excitation of giant resonances, photon decay of giant resonances, the recent controversy over the identity of the giant monopole resonance, the most recent value for incompressibility of nuclear matter from analysis of giant monopole data, the isospin character of the 63 A/sup /minus/1/3/ GQR, agreement between (e,e/prime/) and (hadron, hadron/prime/) excitation of the giant quadrupole resonance, prospects for multiphonon giant resonance observation, and isolation of the isovector giant quadrupole resonance. 55 refs., 23 figs., 4 tabs.

  8. A Broadband Dipolar Resonance in THz Metamaterials

    E-print Network

    Sangala, Bagvanth Reddy; Gopal, Achanta Venu; Prabhu, S S

    2014-01-01

    We demonstrate a THz metamaterial with broadband dipole resonance originating due to the hybridization of LC resonances. The structure optimized by finite element method simulations is fabricated by electron beam lithography and characterized by terahertz time-domain spectroscopy. Numerically, we found that when two LC metamaterial resonators are brought together, an electric dipole resonance arises in addition to the LC resonances. We observed a strong dependence of the width of these resonances on the separation between the resonators. This dependence can be explained based on series and parallel RLC circuit analogies. The broadband dipole resonance appears when both the resonators are fused together. The metamaterial has a stopband with FWHM of 0.47 THz centered at 1.12 THz. The experimentally measured band features are in reasonable agreement with the simulated ones. The experimental power extinction ratio of THz in the stopbands is found to be 15 dB.

  9. Fractional tunnelling resonance in plasmonic media

    PubMed Central

    Kang, Ji-Hun; -Han Park, Q.

    2013-01-01

    Metals can transmit light by tunnelling when they possess skin-depth thickness. Tunnelling can be resonantly enhanced if resonators are added to each side of a metal film, such as additional dielectric layers or periodic structures on a metal surface. Here we show that, even with no additional resonators, tunnelling resonance can arise if the metal film is confined and fractionally thin. In a slit waveguide filled with a negative permittivity metallic slab of thickness L, resonance is shown to arise at fractional thicknesses (L = Const./m; m = 1,2,3,…) by the excitation of ‘vortex plasmons'. We experimentally demonstrate fractional tunnelling resonance and vortex plasmons using microwave and negative permittivity metamaterials. The measured spectral peaks of the fractional tunnelling resonance and modes of the vortex plasmons agree with theoretical predictions. Fractional tunnelling resonance and vortex plasmons open new perspectives in resonance physics and promise potential applications in nanotechnology. PMID:23939460

  10. Optimal cuts to extract the third-order elastic constants of langasite single crystals.

    PubMed

    Zhang, Haifeng

    2011-06-01

    Optimal cuts to determine the third-order elastic constants of langasite single crystals by the resonator method are proposed. By designing a small number of langasite resonators with optimal cut angles and measuring their force-frequency effects, the third-order elastic constants of langasite single crystals may be extracted separately. The numerical method to search for these optimal cut angles is presented. All 14 third-order elastic constants may be determined through a series of experimental measurements. This method will simplify traditional methods used to determine the third-order elastic constants and could potentially produce more accurate results. PMID:21693406

  11. Isospin Breaking in the Extraction of Isovector and Isoscalar Spectral Functions from e^+e^- --> hadrons

    E-print Network

    K. Maltman; C. E. Wolfe

    2000-05-16

    A finite energy sum rule (FESR) analysis of the isospin-breaking vector current correlator is used to determine the isospin-breaking electromagnetic (EM) decay constants of the low-lying vector mesons. These results are used to evaluate the corrections required to extract the flavor diagonal 33 and 88 resonance contributions from the full resonance EM contributions to the EM spectral function. A large (~15%) correction is found in the case of the omega contribution to the isoscalar spectral function. The implications of these results for sum rules based on the isovector-isoscalar spectral difference are considered.

  12. Optically Detected Magnetic Resonance Imaging

    E-print Network

    Blank, Aharon; Fischer, Ran; London, Paz; Gershoni, David

    2014-01-01

    Optically detected magnetic resonance (ODMR) provides ultrasensitive means to detect and image a small number of electron and nuclear spins, down to the single spin level with nanoscale resolution. Despite the significant recent progress in this field, it has never been combined with the power of pulsed magnetic resonance imaging (MRI) techniques. Here, we demonstrate for the first time how these two methodologies can be integrated using short pulsed magnetic field gradients to spatially-encode the sample. This results in what we denote as an "optically detected magnetic resonance imaging" (ODMRI) technique. It offers the advantage that the image is acquired in parallel from all parts of the sample, with well-defined three-dimensional point-spread function, and without any loss of spectroscopic information. In addition, this approach may be used in the future for parallel but yet spatially-selective efficient addressing and manipulation of the spins in the sample. Such capabilities are of fundamental importan...

  13. 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.

  14. Optically detected magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Blank, Aharon; Shapiro, Guy; Fischer, Ran; London, Paz; Gershoni, David

    2015-01-01

    Optically detected magnetic resonance provides ultrasensitive means to detect and image a small number of electron and nuclear spins, down to the single spin level with nanoscale resolution. Despite the significant recent progress in this field, it has never been combined with the power of pulsed magnetic resonance imaging techniques. Here, we demonstrate how these two methodologies can be integrated using short pulsed magnetic field gradients to spatially encode the sample. This result in what we denote as an "optically detected magnetic resonance imaging" technique. It offers the advantage that the image is acquired in parallel from all parts of the sample, with well-defined three-dimensional point-spread function, and without any loss of spectroscopic information. In addition, this approach may be used in the future for parallel but yet spatially selective efficient addressing and manipulation of the spins in the sample. Such capabilities are of fundamental importance in the field of quantum spin-based devices and sensors.

  15. 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.

  16. Precise determination of resonance pole parameters through Padé approximants

    NASA Astrophysics Data System (ADS)

    Masjuan, Pere; Ruiz de Elvira, Jacobo; Sanz-Cillero, Juan José

    2014-11-01

    In this paper, we present a precise and model-independent method to extract resonance pole parameters from phase-shift scattering data. These parameters are defined from the associated poles in the second Riemann sheet, unfolded by the analytic continuation to the complex pole using Padé approximants. Precise theoretical parametrizations of pion-pion scattering phase shifts based on once—and twice—subtracted dispersion relations are used as input, whose functional form allows us to show the benefit and accuracy of the method. In particular, we extract from these parametrizations the pole positions of the f0(500 ) at ?{s }=(453 ±15 )-i (297 ±15 ) MeV , the ? (770 ) at ?{s }=(761.4 ±1.2 )-i (71.8 ±1.0 ) MeV , and the pole of the f2(1270 ), located at ?{s }=(1267.3 ±1.7 )-i (95.0 ±2.3 ) MeV . The couplings of the resonances to two pions are also determined with high precision, obtaining, respectively, 3.8 ±0.4 GeV , 5.92 ±0.15 and 4.41 ±0.23 GeV-1 . Special attention is dedicated to the systematic treatment of the theoretical and statistical uncertainties, together with their comparison with previous determinations.

  17. Studies of Nucleon Resonance Structure in Exclusive Meson Electroproduction

    E-print Network

    I. G. Aznauryan; A. Bashir; V. Braun; S. J. Brodsky; V. D. Burkert; L. Chang; Ch. Chen; B. El-Bennich; I. C. Cloët; P. L. Cole; R. G. Edwards; G. V. Fedotov; M. M. Giannini; R. W. Gothe; F. Gross; Huey-Wen Lin; P. Kroll; T. -S. H. Lee; W. Melnitchouk; V. I. Mokeev; M. T. Peña; G. Ramalho; C. D. Roberts; E. Santopinto; G. F. de Teramond; K. Tsushima; D. J. Wilson

    2013-04-03

    Studies of the structure of excited baryons are key to the N* program at Jefferson Lab. Within the first year of data taking with the Hall B CLAS12 detector following the 12 GeV upgrade, a dedicated experiment will aim to extract the N* electrocouplings at high photon virtualities Q2. This experiment will allow exploration of the structure of N* resonances at the highest photon virtualities ever yet achieved, with a kinematic reach up to Q2 = 12 GeV2. This high-Q2 reach will make it possible to probe the excited nucleon structures at distance scales ranging from where effective degrees of freedom, such as constituent quarks, are dominant through the transition to where nearly massless bare-quark degrees of freedom are relevant. In this document, we present a detailed description of the physics that can be addressed through N* structure studies in exclusive meson electroproduction. The discussion includes recent advances in reaction theory for extracting N* electrocouplings from meson electroproduction off protons, along with QCD-based approaches to the theoretical interpretation of these fundamental quantities. This program will afford access to the dynamics of the non-perturbative strong interaction responsible for resonance formation, and will be crucial in understanding the nature of confinement and dynamical chiral symmetry breaking in baryons, and how excited nucleons emerge from QCD.

  18. Direct detection of time-resolved Rabi oscillations in a single quantum dot via resonance fluorescence

    NASA Astrophysics Data System (ADS)

    Schaibley, J. R.; Burgers, A. P.; McCracken, G. A.; Steel, D. G.; Bracker, A. S.; Gammon, D.; Sham, L. J.

    2013-03-01

    Optical Rabi oscillations are coherent population oscillations of a two-level system coupled by an electric dipole transition when driven by a strong nearly resonant optical field. In quantum dot structures, these measurements have typically been performed as a function of the total pulse area ??0(t)dt where the pulse area varies as a function of Rabi frequency. Here, we report direct detection of the time-resolved coherent transient response of the resonance fluorescence to measure the time evolution of the optical Rabi oscillations in a single charged InAs quantum dot. We extract a decoherence rate consistent with the limit from the excited state lifetime.

  19. A study of the optimum draft of multiple resonance power buoys for maximizing electric power production

    NASA Astrophysics Data System (ADS)

    Kweon, Hyuck-Min; Cho, Hong-Yeon; Cho-Hyoung, ii

    2014-12-01

    To maximize electric power production using wave energy extractions from resonance power buoys, the maximum motion displacement spectra of the buoys can primarily be obtained under a given wave condition. In this study, wave spectra observed in shoaling water were formulated. Target resonance frequencies were established from the arithmetic means of modal frequency bands and the peak frequencies. The motion characteristics of the circular cylindrical power buoys with corresponding drafts were then calculated using numerical models without considering PTO damping force. Results showed that the heave motions of the power buoys in shoaling waters with insufficient drafts produced greater amplification effects than those in deep seas with sufficient drafts.

  20. Characterization of proton beam emission from an electron cyclotron resonance ion source

    NASA Astrophysics Data System (ADS)

    Jain, S. K.; Tayyab, M.; Bagchi, S.; Chakera, J. A.; Naik, P. A.

    2013-04-01

    We report here characterization of the ions produced in the Electron Cyclotron Resonance Ion Source (ECRIS) at RRCAT, which operates at 2.45 GHz and is aimed to produce a 50 keV, 30 mA proton beam. The plasma in the source was created using microwave power in the range of 150-1200 W. An efficient, single hole, three-electrode ion extraction system was employed to extract the ion beam from the ECRIS, and the extracted ion beam was characterized using a Thomson Parabola Ion Spectrograph, which provides complete information of all the differently charged species present in the plasma. The extracted ion beam current measured up to 8 mA beam current for 25 keV accelerating field and followed the Child-Langmuir law.