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Sample records for quadrupole interaction study

  1. Ab initio Study of Nuclear Quadrupole Interactions in Selenium and Tellurium

    NASA Astrophysics Data System (ADS)

    Maharjan, N. B.; Paudyal, D. D.; Mishra, D. R.; Byahut, S. P.; Cho, Hwa-Suck; Scheicher, R. H.; Jeong, Junho; Das, T. P.

    2004-03-01

    We are systematically studying the influence of impurities in calcogenide glasses on the glass transition temperature using the first-principles Hartree-Fock cluster method. Results of our calculations on the electronic structures of pure selenium and tellurium chain systems, and with Te and Se impurities respectively, will be reported. By comparing the theoretically obtained nuclear quadrupole interaction (NQI) tensors for ^77Se and ^125Te with available experimental NQI tensors, we were able to test the accuracy of the calculated electronic structures. Good agreement for both the pure and the impurity systems has been found. We have also studied ^125Te NQI tensors in Te-Thiourea and compared our result with experimental data to check on the choice of the ^125Te quadrupole moment used.

  2. First Principles Study of Nuclear Quadrupole Interactions in Single and Double Chain DNA and Solid Nucleobases

    NASA Astrophysics Data System (ADS)

    Das, T. P.; Pink, R. H.; Badu, S. R.; Dubey, Archana; Scheicher, R. H.; Saha, H. P.; Chow, Lee; Huang, M. B.

    2009-03-01

    Nuclear Quadrupole Interactions (NQI) of ^17O, ^14N and ^2H nuclei have been studied for free nucleobases and nucleobases in single strand and double strand DNA and in solid state. Our first-principles investigations were carried out using the Gaussian 2003 set of programs to implement the Hartree-Fock procedure combined with many-body effects included using many-body perturbation theory. As expected for NQI in general, many-body effects are found to be small. Results will be presented for the quadrupole coupling constants (e^2qQ) and asymmetry parameters (η) for the nucleobases in the various environments. Trends in e^2qQ and η in the different environments will be discussed. In the case of the solid nucleobases, comparisons will be made with available experimental data [1] for ^17O nuclei.[3pt] [1] Gang Wu et al., J. Am. Chem. Soc. 124, 1768 (2002)

  3. Quench antenna studies of mechanical and quench performance in Fermilab interaction region quadrupoles for LHC

    SciTech Connect

    Tartaglia, M.A.; Feher, S.; Hocker, A.; Lamm, M.; Schlabach, P.; Sylvester, C.; Tompkins, J.C.; /Fermilab

    2005-09-01

    As part of the US-LHC collaboration, Fermilab has built and tested seventeen high gradient quadrupole magnets, assembled into nine cryostats, for installation at the Large Hadron Collider Interaction Regions. Most of these magnets have only quarter coil voltage taps for quench characterization, but the magnetic measurement warm bore is instrumented with a quench antenna for localization and characterization. We report on studies using the quench antenna for pre-production prototype (with extensive voltage taps) and 17 production magnets. These include a summary of quench localization and development characteristics, as well as general features of flux changes observed during training ramps.

  4. Hartree-Fock Cluster Study of Electronic Structures and Nuclear Quadrupole Interactions in Solid Nucleobases.

    NASA Astrophysics Data System (ADS)

    Scheicher, R. H.; Dubey, Archana; Badu, S. R.; Saha, H. P.; Pink, R. H.; Nagamine, K.; Torikai, E.; Chow, Lee; Das, T. P.

    2008-03-01

    In recent work [1] we have studied nucleobases attached to a CH3 group to simulate the influence of their binding to the sugar rings and the phosphate groups in DNA and RNA and the effect of this binding on the nuclear quadrupole interactions of ^14N, ^17O and ^2H nuclei. Our results from this work have indicated that for ^17O, the binding to the CH3 group moves our results from the free nucleobases closer to the experimentally observed data [2] in the solid nucleobases. We are now investigating the solid nucleobases by the first --principles Hartree-Fock cluster procedure that we have employed earlier for the halogen molecular solids [3]. Our results for the binding energy of an imidazole molecule in the molecular solid system and the ^14N, ^17O and ^2H nuclear quadrupole interaction parameters will be presented. [1] T.P. Das et al (at this APS meeting), [2] Gang Wu et al, J. Am.Chem. Soc. 124, 1768(2002). [3] M.M. Aryal et al Hyperfine Interactions (to be published).

  5. Nuclear electric quadrupole interactions in liquids entrapped in cavities

    NASA Astrophysics Data System (ADS)

    Furman, Gregory B.; Meerovich, Victor M.; Sokolovsky, Vladimir L.

    2016-12-01

    Liquids entrapped in cavities and containing quadrupole nuclei are considered. The interaction of the quadrupole moment of a nucleus with the electric field gradient is studied. In such a system, molecules are in both rotational and translational Brownian motions which are described by the diffusion equation. Solving this equation, we show that the intra- and intermolecular nuclear quadrupole interactions are averaged to zero in cavities with the size larger than several angstroms.

  6. Nuclear quadrupole resonance studies in semi-metallic structures

    NASA Technical Reports Server (NTRS)

    Murty, A. N.

    1974-01-01

    Both experimental and theoretical studies are presented on spectrum analysis of nuclear quadrupole resonance of antimony and arsenic tellurides. Numerical solutions for secular equations of the quadrupole interaction energy are also discussed.

  7. Thermal analysis of SC quadrupoles in accelerator interaction regions

    SciTech Connect

    Novitski, Igor; Zlobin, Alexander V.; /Fermilab

    2006-09-01

    This paper presents results of a thermal analysis and operation margin calculation performed for NbTi and Nb{sub 3}Sn low-beta quadrupoles in collider interaction regions. Results of the thermal analysis for NbTi quadrupoles are compared with the relevant experimental data. An approach to quench limit measurements for Nb{sub 3}Sn quadrupoles is discussed.

  8. Test results of LHC interaction regions quadrupoles produced by Fermilab

    SciTech Connect

    Bossert, R.; Carson, J.; Chichili, D.R.; Feher, S.; Kerby, J.; Lamm, M.J.; Nobrega, A.; Nicol, T.; Ogitsu, T.; Orris, D.; Page, T.; Peterson, T.; Rabehl, R.; Robotham, W.; Scanlan, R.; Schlabach, P.; Sylvester, C.; Strait, J.; Tartaglia, M.; Tompkins, J.C.; Velev, G.; /Fermilab

    2004-10-01

    The US-LHC Accelerator Project is responsible for the production of the Q2 optical elements of the final focus triplets in the LHC interaction regions. As part of this program Fermilab is in the process of manufacturing and testing cryostat assemblies (LQXB) containing two identical quadrupoles (MQXB) with a dipole corrector between them. The 5.5 m long Fermilab designed MQXB have a 70 mm aperture and operate in superfluid helium at 1.9 K with a peak field gradient of 215 T/m. This paper summarizes the test results of several production MQXB quadrupoles with emphasis on quench performance and alignment studies. Quench localization studies using quench antenna signals are also presented.

  9. Nuclear spin squeezing via electric quadrupole interaction

    NASA Astrophysics Data System (ADS)

    Aksu Korkmaz, Yaǧmur; Bulutay, Ceyhun

    2016-01-01

    Control over nuclear-spin fluctuations is essential for processes that rely on preserving the quantum state of an embedded system. For this purpose, squeezing is a viable alternative, so far that has not been properly exploited for the nuclear spins. Of particular relevance in solids is the electric quadrupole interaction (QI), which operates on nuclei having spin higher than 1/2. In its general form, QI involves an electric-field gradient (EFG) biaxiality term. Here, we show that as this EFG biaxiality increases, it enables continuous tuning of single-particle squeezing from the one-axis twisting to the two-axis countertwisting limits. A detailed analysis of QI squeezing is provided, exhibiting the intricate consequences of EFG biaxiality. The initial states over the Bloch sphere are mapped out to identify those favorable for fast initial squeezing, or for prolonged squeezings. Furthermore, the evolution of squeezing in the presence of a phase-damping channel and an external magnetic field are investigated. We observe that dephasing drives toward an antisqueezed terminal state, the degree of which increases with the spin angular momentum. Finally, QI squeezing in the limiting case of a two-dimensional EFG with a perpendicular magnetic field is discussed, which is of importance for two-dimensional materials, and the associated beat patterns in squeezing are revealed.

  10. Photoassociation of a cold-atom-molecule pair: Long-range quadrupole-quadrupole interactions

    SciTech Connect

    Lepers, M.; Dulieu, O.; Kokoouline, V.

    2010-10-15

    The general formalism of the multipolar expansion of electrostatic interactions is applied to the calculation of the potential energy between an excited atom (without fine structure) and a ground-state diatomic molecule at large mutual separations. Both partners exhibit a permanent quadrupole moment so that their mutual long-range interaction is dominated by a quadrupole-quadrupole term, which is attractive enough to bind trimers. Numerical results are given for an excited Cs(6{sup 2}P) atom and a ground-state Cs{sub 2} molecule. The prospects for achieving photoassociation of a cold-atom-dimer pair are thus discussed and found promising. The formalism can be generalized to the long-range interaction between molecules to investigate the formation of cold tetramers.

  11. Bench Marking Accuracies of Variational Methods for Studying Molecular and Solid State Properties by Application to Nuclear Quadrupole Interactions in Boron and Aluminum Atoms

    NASA Astrophysics Data System (ADS)

    Pink, R. H.; Dubey, Archan; Badu, S. R.; Scheicher, R. H.; Chow, Lee; Das, T. P.

    2011-03-01

    As part of a test of the accuracy of the variational methods (VHFMBPT) and (VDFT) for energy and wave-function dependent properties in molecular and solid state systems, the nuclear quadrupole interactions in the ground state of boron and aluminum atoms are being studied by these methods. Results for the electric field gradients will be presented for these atoms and compared with experiment , and with results , of the highly accurate LCMBPT procedure for the atoms. Conclusions about the factors governing the accuracies of the variational methods will be presented. J.S.M. Harvey, L. Evans, and H. Lew, Can. J. Phys. 50, 1719 (1972)

  12. Nuclear magnetic and quadrupole resonance in metallic powders in the presence of strong quadrupole interaction: Rhenium metal

    SciTech Connect

    Dimitropoulos, C.; Maglione, M.; Borsa, F.

    1988-03-01

    The nuclear-magnetic-resonance and nuclear-quadrupole-resonance (NQR-NMR) spectra of /sup 187/Re and /sup 185/Re in a powder of rhenium metal were measured in the temperature range 5--10 K both in zero field and with an external magnetic field. The zero-field NQR spectrum is severely broadened by a nonuniform distribution of quadrupole interactions. The average quadrupole coupling frequencies measured at 5 K are, for the two isotopes, ..nu../sub Q/ = 39 +- 0.2 MHz (/sup 187/Re) and ..nu../sub Q/ = 40.8 +- 0.3 MHz (/sup 185/Re). The spectra obtained in the presence of an external magnetic field can be interpreted satisfactorily in terms of transitions among the eigenstates of the full Hamiltonian (Zeeman plus quadrupolar). Measurements of relaxation rates yield T/sub 1/T = 0.03 sK, indicating a relaxation mechanism driven by the hyperfine interaction with the conduction electrons. The feasibility of NQR-NMR studies in small metal particles in the presence of strong inhomogeneous quadrupole interactions is assessed

  13. The Pipe-Quadrupole, an Alternative for High Gradient Interaction Region Quadrupole Designs

    SciTech Connect

    Oort, J.M. van; Scanlan, R.M.

    1996-12-12

    In the design of interaction region (IR) quadrupoles for high luminosity colliders such as the LHC or a possible upgrade of the Tevatron, the radiation heating of the coil windings is an important issue. Two obvious solutions to this problem can be chosen. The first is to reduce the heat load by added shielding, increased cooling with fins or using Nb{sub 3}Sn to increase the temperature margin. The second solution eliminates the conductor from the areas with the highest radiation intensity, which are located on the symmetry-axes of the midplanes of the coils. A novel quadrupole design is presented, in which the conductor is wound on four half-moon shaped supports, forming elongated toroid sections. The assembly of the four shapes yields a quadrupole field with an active flux return path, and a void in the high radiation area. This void can be occupied by a liquid helium cooling pipe to lower the temperature of the windings from the inside. The coil layout, harmonic optimization and mechanical design are shown, together with the calculated temperature rise for the radiation load of the LHC interaction region quadrupoles.

  14. Gravitational radiation quadrupole formula is valid for gravitationally interacting systems

    NASA Technical Reports Server (NTRS)

    Walker, M.; Will, C. M.

    1980-01-01

    An argument is presented for the validity of the quadrupole formula for gravitational radiation energy loss in the far field of nearly Newtonian (e.g., binary stellar) systems. This argument differs from earlier ones in that it determines beforehand the formal accuracy of approximation required to describe gravitationally self-interacting systems, uses the corresponding approximate equation of motion explicitly, and evaluates the appropriate asymptotic quantities by matching along the correct space-time light cones.

  15. 120-mm supercondcting quadrupole for interaction regions of hadron colliders

    SciTech Connect

    Zlobin, A.V.; Kashikhin, V.V.; Mokhov, N.V.; Novitski, I.; /Fermilab

    2010-05-01

    Magnetic and mechanical designs of a Nb{sub 3}Sn quadrupole magnet with 120-mm aperture suitable for interaction regions of hadron colliders are presented. The magnet is based on a two-layer shell-type coil and a cold iron yoke. Special spacers made of a low-Z material are implemented in the coil mid-planes to reduce the level of radiation heat deposition and radiation dose in the coil. The quadrupole mechanical structure is based on aluminum collars supported by an iron yoke and a stainless steel skin. Magnet parameters including maximum field gradient and field harmonics, Nb3Sn coil pre-stress and protection at the operating temperatures of 4.5 and 1.9 K are reported. The level and distribution of radiation heat deposition in the coil and other magnet components are discussed.

  16. Quadrupole beam-based alignment in the RHIC interaction regions

    SciTech Connect

    Ziegler, J.; Satogata, T.

    2011-03-28

    Continued beam-based alignment (BBA) efforts have provided significant benefit to both heavy ion and polarized proton operations at RHIC. Recent studies demonstrated previously unknown systematic beam position monitor (BPM) offset errors and produced accurate measurements of individual BPM offsets in the experiment interaction regions. Here we describe the algorithm used to collect and analyze data during the 2010 and early 2011 RHIC runs and the results of these measurements. BBA data has been collected over the past two runs for all three of the active experimental IRs at RHIC, updating results from the 2005 run which were taken with incorrectly installed offsets. The technique was successfully applied to expose a systematic misuse of the BPM survey offsets in the control system. This is likely to benefit polarized proton operations as polarization transmission through acceleration ramps depends on RMS orbit control in the arcs, but a quantitative understanding of its impact is still under active investigation. Data taking is ongoing as are refinements to the BBA technique aimed at reducing systematic errors and properly accounting for dispersive effects. Further development may focus on non-triplet BPMs such as those located near snakes, or arc quadrupoles that do not have individually shunted power supplies (a prerequisite for the current method) and as such, will require a modified procedure.

  17. In-vivo study of the nuclear quadrupole interaction of99Mo (β- 99)Tc in nitrogenase of Klebsiella pneumoniaein nitrogenase of Klebsiella pneumoniae

    NASA Astrophysics Data System (ADS)

    Mottner, P.; Lerf, A.; Ni, X.; Butz, T.; Erfkamp, J.; Müller, A.

    1990-08-01

    We report on the first TDPAC-measurements of the nuclear quadrupole interaction (NQI) of (NQI) of99Mo(β-)99Tc in the nitrogenase of the bacteria Klebsiella pneumoniae. Because nitrogenase is the only Mo-containing enzyme in Klebsiella pneumoniae under the chosen conditions, no further isolation of this enzyme was necessary. The majority of the incorporated99Mo is subjected to a well defined NQI with ω=365(7) Mrad/s, η=1 and a reorientational correlation time of τcoττ≈10nsec and is attributed to the active site of the FeMo cofactor. During sample preparation we noted a pronounced affinity of the bacteria to99mTc.

  18. Quadrupole resonance spectroscopic study of narcotic materials

    NASA Astrophysics Data System (ADS)

    Rayner, Timothy J.; West, Rebecca; Garroway, Allen N.; Lyndquist, R.; Yesinowski, James P.

    1997-02-01

    Bulk narcotic detection systems based upon Quadrupole Resonance Analysis (QRA) technology have a major advantage over imaging technologies, in that QRA is chemical-specific and consequently has a lower rate of false alarms. QRA is a magnetic resonance technology which occurs as a result of the inherent molecular properties of the atomic nuclei in crystalline and amorphous solids. The QRA response is characterized by 1) the precessional frequency of the nucleus, and 2) the nature of the electric field gradient experienced by the nucleus,due to its molecular environment. Another important detection parameter is linewidth, resonant quality. All of these parameters depend on sample purity and manufacturing process. Quantum Magnetics recently carried out a study on the QRA signatures of various narcotic materials with the support of the US Army, US Customs, and the Office of National Drug Control Policy. The aim of the study was to fully characterize the variation in QRA spectroscopic parameters of different samples of cocaine base and cocaine hydrochloride. The results from this study ar discussed here.

  19. Nuclear Quadrupole Resonance Study of Potassium - - Chloride.

    NASA Astrophysics Data System (ADS)

    Ramia, Maximo Elias

    Fast Fourier transform nuclear quadrupole resonance (NQR) was used to study the cubic antifluorite crystal potassium hexacloro-osmate, K(,2)OsCl(,6). The study of the ('35)Cl and ('37)Cl resonances were performed on three samples of K(,2)OsCl(,6), a powder sample, a powder sample recrystallized from D(,2)O and a single crystal sample. The studies were carried out in the temperature range 300 to 6K. A detailed study of the ('35)Cl and ('37)Cl NQR lineshapes, in the temperature range 70 to 300K, showed that the lineshapes reflect the strain fields produced by lattice dislocations and point defects. The temperature evolution of these strain fields give rise to a satellite line which previously was attributed to H('+) ion impurities present in the samples. A comprehensive study of the temperature evolution of the NQR spectrum in the vicinity of the phase transition revealed a drop of line intensity and the progressive appearance of an extra broad resonance component. Both effects are associated with the existence of precursor dynamic clusters at temperatures higher than T(,C). Qualitatively similar but quantitatively different behaviour was observed in the powder and single crystal samples. Although the precursor clusters are an intrinsic property of the phrase transition, their detailed dynamics is sample independent. A NQR study of the tetragonal phase showed that at the lowest temperature the ratio of line intensities is 2:1. The phase shift effect previously observed in the tetragonal phase of K(,2)ReCl(,6) was also observed in K(,2)OsCl(,6). The effect has been explained as an experimental artifact introduced by the truncation of the FID due to the spectrometer dead time. Spin-lattice relaxation measurements in the cubic phase show two component relaxation in the vicinity of T(,C). The behaviour is quantitatively different in the powder and single crystal samples. The short relaxation time is associated with dynamic clusters. Spin-lattice relaxation time

  20. Study the most favorable shapes of electrostatic quadrupole doublet lenses

    NASA Astrophysics Data System (ADS)

    Hussein, O. A.; Sise, O.

    2017-02-01

    The optical properties of an electrostatic quadrupole doublet lens with two different electrode shapes were studied with the aid of computer simulation. The optimal electrode voltages of the electrostatic quadrupole lenses which give the stigmatic image in both planes simultaneously were found for both concave cylindrical electrode shape and plan electrode shape of the operation mode: parallel to point focusing. The effect of electrode shape on the image properties was investigated, and the aberration figures were studied. The results showed that under the same operation condition and the geometrical dimensions, the changing of the electrode shape of the electrostatic quadrupole doublet lenses lead to important differences in the optical properties of the lenses and the characteristics of the systems.

  1. Quantum aspects of a moving magnetic quadrupole moment interacting with an electric field

    SciTech Connect

    Fonseca, I. C.; Bakke, K.

    2015-06-15

    The quantum dynamics of a moving particle with a magnetic quadrupole moment that interacts with electric and magnetic fields is introduced. By dealing with the interaction between an electric field and the magnetic quadrupole moment, it is shown that an analogue of the Coulomb potential can be generated and bound state solutions can be obtained. Besides, the influence of the Coulomb-type potential on the harmonic oscillator is investigated, where bound state solutions to both repulsive and attractive Coulomb-type potentials are achieved and the arising of a quantum effect characterized by the dependence of the harmonic oscillator frequency on the quantum numbers of the system is discussed.

  2. Interrelations between the pairing and quadrupole interactions in the microscopic Shell Model

    NASA Astrophysics Data System (ADS)

    Drumev, K. P.; Georgieva, A. I.

    2016-01-01

    We explore the dynamical symmetries of the shell model number conserving algebra, which define three types of pairing and quadrupole phases, with the aim to obtain the prevailing phase or phase transition for the real nuclear systems in a single shell. This is achieved by establishing a correspondence between each of the pairing bases with the Elliott's SU(3) basis that describes collective rotation of nuclear systems. This allows for a complete classification of the basis states of different number of particles in all the limiting cases. The probability distribution of the SU(3) basis states within theirs corresponding pairing states is also obtained. The relative strengths of dynamically symmetric quadrupole-quadrupole interaction in respect to the isoscalar, isovector and total pairing interactions define a control parameter, which estimates the importance of each term of the Hamiltonian in the correct reproduction of the experimental data for the considered nuclei.

  3. Vapor-liquid equilibria simulation and an equation of state contribution for dipole-quadrupole interactions.

    PubMed

    Vrabec, Jadran; Gross, Joachim

    2008-01-10

    A systematic investigation on vapor-liquid equilibria (VLEs) of dipolar and quadrupolar fluids is carried out by molecular simulation to develop a new Helmholtz energy contribution for equations of state (EOSs). Twelve two-center Lennard-Jones plus point dipole and point quadrupole model fluids (2CLJDQ) are studied for different reduced dipolar moments micro*2=6 or 12, reduced quadrupolar moments Q*2=2 or 4 and reduced elongations L*=0, 0.505, or 1. Temperatures cover a wide range from about 55% to 95% of the critical temperature of each fluid. The NpT+test particle method is used for the calculation of vapor pressure, saturated densities, and saturated enthalpies. Critical data and the acentric factor are obtained from fits to the simulation data. On the basis of this data, an EOS contribution for the dipole-quadrupole cross-interactions of nonspherical molecules is developed. The expression is based on a third-order perturbation theory, and the model constants are adjusted to the present 2CLJDQ simulation results. When applied to mixtures, the model is found to be in excellent agreement with results from simulation and experiment. The new EOS contribution is also compatible with segment-based EOS, such as the various forms of the statistical associating fluid theory EOS.

  4. Nuclear quadrupole interaction of highly polarized gas phase 131Xe with a glass surface

    NASA Astrophysics Data System (ADS)

    Butscher, R.; Wäckerle, G.; Mehring, M.

    1994-05-01

    We report nuclear magnetic resonance (NMR) experiments on 131Xe (I=3/2) gas-phase atoms which exhibit nuclear quadrupole interaction with the surface of the sample cell. Nuclear quadrupole coupling constants and quadrupole relaxation rates are obtained from the time-domain signal of the freely precessing nuclear magnetization in weak magnetic fields. The nuclear spin species is polarized by spin-exchange collisions with optically pumped ground-state spins of Rb gas atoms. The Rb atoms also present in the sample are used as a magnetometer to probe the free-induction decay of the nuclear-spin ensemble. The temperature dependence of both the effective quadrupole splittings and the relaxation rates are explained by a model for the surface interactions of a Xe atom adsorbed on the glass surface. The desorption is thermally activated with an activation energy of EA=0.12 eV. The surface diffusion of an adsorbed atom is characterized by an activation energy ED for thermally activated hopping between neighboring surface sites. Both energies enter the spectral density function governing wall-induced nuclear quadrupole relaxation. Our experimental results lead to the conclusion that they are on the same order of magnitude.

  5. Homotopy analysis method to study a quadrupole mass filter.

    PubMed

    Seddighi Chaharborj, S; Seddighi Chahrborj, S; Sadat Kiai, S M; Abu Bakar, M R; Ziaeian, I; Gheisari, Y

    2012-04-01

    The homotopy analysis method (HAM) is applied to study the behavior of a hyperbolic rods of quadrupole mass filter and a sinusoidal potential form V(ac)  cos(Ωt). Numerical computation method of a 20th-order HAM is employed to compare the physical properties of the confined ions with fifth-order Runge-Kutta method. Also, comparison is made for the first stability region, the ion trajectories in real time, the polar plots, and the ion trajectory in x - y plan. The results show that the two methods are fairly similar; therefore, the HAM method has potential application to solve linear and nonlinear equations of the charge particle confinement in quadrupole field. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Accurate measurements of electric quadrupole hyperfine interactions of very dilute spins in magnetic solids

    NASA Astrophysics Data System (ADS)

    Chaplin, D. H.; Hutchison, W. D.; Prandolini, M. J.; Bowden, G. J.

    1998-01-01

    The application of double and triple resonance techniques to enhance signals in quadrupole interaction — nuclear magnetic resonance on oriented nuclei spectroscopy, is illustrated for the antiferromagnet ( 54Mn)MnBr 2-4H 2O. Unusual shifts of the quadrupolar split, higher order, ν ±2, ±1 subresonance, comparable to the NMRON linewidth, are observed and explained.

  7. Robust correlations between quadrupole moments of low-lying 2+ states within random-interaction ensembles

    NASA Astrophysics Data System (ADS)

    Lei, Y.

    2016-02-01

    In random-interaction ensembles, three proportional correlations between quadrupole moments of the first two Iπ=2+ states robustly emerge, including Q (21+) =±Q (22+) correlations previously remarked by a realistic nuclear survey, and the Q (22+) =-3/7 Q (21+) correlation, which is only observed in the s d -boson space. These correlations can be microscopically characterized by the rotational SU(3) symmetry and quadrupole vibrational U(5) limit, respectively, according to the Elliott model and the s d -boson mean-field theory. The anharmonic vibration may be another phenomenological interpretation for the Q (21+) =-Q (22+) correlation, whose spectral evidence, however, is insufficient.

  8. Nuclear collective motion with a coherent coupling interaction between quadrupole and octupole modes

    NASA Astrophysics Data System (ADS)

    Minkov, N.; Yotov, P.; Drenska, S.; Scheid, W.; Bonatsos, D.; Lenis, D.; Petrellis, D.

    2006-04-01

    A collective Hamiltonian for the rotation-vibration motion of nuclei is considered in which the axial quadrupole and octupole degrees of freedom are coupled through the centrifugal interaction. The potential of the system depends on the two deformation variables β2 and β3. The system is considered to oscillate between positive and negative β3 values by rounding an infinite potential core in the (β2,β3) plane with β2>0. By assuming a coherent contribution of the quadrupole and octupole oscillation modes in the collective motion, the energy spectrum is derived in an explicit analytic form, providing specific parity shift effects. On this basis several possible ways in the evolution of quadrupole-octupole collectivity are outlined. A particular application of the model to the energy levels and electric transition probabilities in alternating parity spectra of the nuclei Nd150, Sm152, Gd154, and Dy156 is presented.

  9. Precision nuclear orientation measurements for determining mixed magnetic dipole/electric quadrupole hyperfine interactions

    NASA Astrophysics Data System (ADS)

    Brewer, W. D.; Roman, P.; Marshak, H.

    1989-06-01

    We report the temperature dependence of the gamma-ray anisotropies from oriented160Tb nuclei produced by neutron activation of the central portion of a high-purity single crystal Tb slab. The magnetically saturated sample was studied over a wide temperature range from 18 mK to 150 mK. The temperatures were determined using precision resistance thermometry with in situ calibration by a magnetically shielded six-element superconducting fixed point device. Temperature stability during data acquisition was better than 0.1%, and least-squares fitting of the resulting temperature dependences of 0° and 90° anisotropies allowed both the magnetic dipole and the electric quadrupole hyperfine interaction frequencies to be determined with good accuracy. The weighted averages for 18 gamma rays are v M=1393.8 (8.1) MHz and v P=178.0 (2.1) MHz, in excellent agreement with NMR results on ion-implanted samples.

  10. Residual quadrupole interaction in brain and its effect on quantitative sodium imaging.

    PubMed

    Stobbe, Robert W; Beaulieu, Christian

    2016-02-01

    Sodium MRI is particularly interesting given the key role that sodium ions play in cellular metabolism. To measure concentration, images must be free from contrast unrelated to sodium density. However, spin 3/2 NMR is complicated by more than rapid biexponential signal decay. Residual quadrupole interactions (described by frequency ωQ) can reduce Mxy development during RF excitation. Three experiments, each performed on the same four healthy volunteers, demonstrate that residual quadrupole interactions are of concern in quantitative sodium imaging of the brain. The first experiment shows a reliable increase in the rate of excitation 'flipping' (1%-6%), particularly in white matter with tracts running superior-inferior (i.e. parallel to B0). Increased flip-rates imply an associated signal loss and are to be expected when ωQ ~ ω1. The second experiment shows that a prescribed flip-angle decrease from 90° to 20°, with concomitant decrease in TE from 0.25 ms to 0.10 ms and no T1 weighting, results in a 14%-26% saline calibration phantom normalized signal (SN) increase in the white matter regions. The third experiment shows that this (SN) increase is primarily due to a residual quadrupole effect, with a small contribution from T2 weighting. There is an observed deviation from the spin 3/2 biexponential curve, also suggesting ωQ dephasing. Using simulation to explain the results of all three experiments, a model of brain tissue is hypothesized. It includes one pool (50%) with ωQ = 0, and another (50%) in which ωQ has a Gaussian distribution with a standard deviation of 625 Hz. Given the result of the second experiment, it is suggested that the use of reduced flip-angles with large ω1 will provide more accurate measures of sodium concentration than 'standard' methods using 90° pulses. Alternatively, further study of sodium ωQmay provide a means to explore tissue structure and organization. Copyright © 2015 John Wiley & Sons, Ltd.

  11. Topology of the interactions pattern in pharmaceutically relevant polymorphs of methylxanthines (caffeine, theobromine, and theophiline): combined experimental (¹H-¹⁴N nuclear quadrupole double resonance) and computational (DFT and Hirshfeld-based) study.

    PubMed

    Latosińska, Jolanta Natalia; Latosińska, Magdalena; Olejniczak, Grzegorz A; Seliger, Janez; Žagar, Veselko

    2014-09-22

    Three anhydrous methylxanthines: caffeine (1,3,7-trimethylxanthine; 1,3,7-trimethyl-1H-purine-2,6-(3H,7H)-dione) and its two metabolites theophylline (1,3-dimethylxanthine; 1,3-dimethyl-7H-purine-2,6-dione) and theobromine (3,7-dimethyl-xanthine; 3,7-dimethyl-7H-purine-2,6-dione), which reveal multifaceted therapeutic potential, have been studied experimentally in solid state by (1)H-(14)N NMR-NQR (nuclear magnetic resonance-nuclear quadrupole resonance) double resonance (NQDR). For each compound the complete NQR spectrum consisting of 12 lines was recorded. The multiplicity of NQR lines indicates the presence of a stable β form of anhydrous caffeine at 233 K and stable form II of anhydrous theobromine at 213 K. The assignment of signals detected in NQR experiment to particular nitrogen atoms was made on the basis of quantum chemistry calculations performed for monomer, cluster, and solid at the DFT/GGA/BLYP/DPD level. The shifts due to crystal packing interactions were evaluated, and the multiplets detected by NQR were assigned to N(9) in theobromine and N(1) and N(9) in caffeine. The ordering theobromine > theophylline > caffeine site and theophylline < theobromine < caffeine according to increasing electric field gradient (EFG) at the N(1) and N(7) sites, respectively, reflects the changes in biological activity profile of compounds from the methylxanthines series (different pharmacological effects). This difference is elucidated on the basis of the ability to form intra- and intermolecular interactions (hydrogen bonds and π···π stacking interactions). The introduction of methyl groups to xanthine restricts the ability of nitrogen atoms to participate in strong hydrogen bonds; as a result, the dominating effect shifts from hydrogen bond (theobromine) to π···π stacking (caffeine). Substantial differences in the intermolecular interactions in stable forms of methylxanthines differing in methylation (site or number) were analyzed within the Hirshfeld

  12. Nuclear quadrupole resonance studies project. [spectrometer design and spectrum analysis

    NASA Technical Reports Server (NTRS)

    Murty, A. N.

    1978-01-01

    The participation of undergraduates in nuclear quadrupole resonance research at Grambling University was made possible by NASA grants. Expanded laboratory capabilities include (1) facilities for high and low temperature generation and measurement; (2) facilities for radio frequency generation and measurement with the modern spectrum analyzers, precision frequency counters and standard signal generators; (3) vacuum and glass blowing facilities; and (4) miscellaneous electronic and machine shop facilities. Experiments carried out over a five year period are described and their results analyzed. Theoretical studies on solid state crystalline electrostatic fields, field gradients, and antishielding factors are included.

  13. Small Aperture BPM to Quadrupole Assembly Tolerance Study

    SciTech Connect

    Fong, K. W.

    2010-12-07

    The LCLS injector and linac systems utilize a series of quadrupole magnets with a beam position monitor (BPM) captured in the magnet pole tips. The BPM measures the electron beam position by comparing the electrical signal from 4 electrodes and interpolating beam position from these signals. The manufacturing tolerances of the magnet and BPM are critical in determining the mechanical precision of the electrodes relative to the nominal electron beam Z-axis. This study evaluates the statistical uncertainty of the electrodes center axis relative to the nominal electron beam axis.

  14. Electron Distributions in Hexagonal Selenium and Tellurium and Monoclinic Selenium with Dilute Impurities and Associated Nuclear Quadrupole Interactions*.

    NASA Astrophysics Data System (ADS)

    Maharjan, N. B.; Paudyal, D. D.; Mishra, D. R.; Byahut, S.; Aryal, M. M.; Cho, Hwa-Suck; Scheicher, R. H.; Chow, Lee; Jeong, Junho; Das, T. P.

    2006-03-01

    The electron structures of Selenium chains and rings with Te impurities in hexagonal and monoclinic structures respectively and Se impurities in Te chains in hexagonal lattice have been studied using Hartree-Fock cluster model including many-body effects, including lattice relaxation effects. The calculated electronic wave-functions are utilized to obtain ^77Se and ^125Te nuclear quadrupole coupling constants e^2qQ and asymmetry parameters η and compared with available experimental data from Mossbauer and perturbed angular correlation measurements. From our results, the expected nature of nuclear quadrupole interactions associated with Sb impurities will be discussed. *Supported by NSF US-Nepal Program and UGC Nepal **Also at UCF, Orlando

  15. Quadrupole interactions: NMR, NQR, and in between from a single viewpoint.

    PubMed

    Bain, Alex D

    2017-03-01

    Nuclear spins with quantum numbers >1/2 can interact with a static magnetic field, or a local electric field gradient, to produce quantized energy levels. If the magnetic field interaction dominates, we are doing nuclear magnetic resonance (NMR). If the interaction of the nuclear electric quadrupole with electric field gradients is much stronger, this is nuclear quadrupole resonance (NQR). The two are extremes of a continuum, as the ratio of one interaction to the other changes. In this work, we look at this continuum from a single, unified viewpoint based on a Liouville-space approach: the direct method. This method does not require explicit operators and their commutators, unlike Hamiltonian methods. We derive both the quadrupole-perturbed NMR solution and also the Zeeman-perturbed NQR results. Furthermore, we examine the polarization of these signals, because this is different between pure NMR and pure NQR spectroscopy. Spin 3/2 is the focus here, but the approach is perfectly general and can be applied to any spin. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Interplay between the pairing and quadrupole interactions in the algebraic realization of the microscopic shell model

    NASA Astrophysics Data System (ADS)

    Drumev, Kalin; Georgieva, Ana

    2015-04-01

    We explore the algebraic realization of the Pairing-Plus-Quadrupole Model/PQM/ in the framework of the Elliott‘s SU(3) Model with the aim to obtain the complementary and competing features of the two interactions through the relation between the pairing and the SU(3) bases. First, we establish a correspondence between the SO(8) pairing basis and the Elliott's SU(3) basis. It is derived from their complementarity to the same LST coupling chain of the shell-model number-conserving algebra. The probability distribution of the SU(3) basis states within the SO(8) pairing states is also obtained and allows the investigation of the interplay between the pairing and quadrupole interactions in the Hamiltonian of the PQM, containing both of them as limiting cases. The description of some realistic N∼Z nuclear systems is investigated in a SU(3)-symmetry-adapted basis within a model space of one and two oscillator shells.

  17. Nuclear quadrupole resonance study of hydrogen bonded solid materials.

    PubMed

    Seliger, Janez

    2011-09-01

    Nuclear quadrupole resonance is presented as a method for the study of solid hydrogen bonded materials. NQR study of hydrogen bonds in ferroelectric and paraelectric KH2PO4, antiferroelectric and paraelectric squaric acid, ferroelectric croconic acid and antiferroelectric and paraelectric cocrystal 5'-dimethyl-2, 2'-bipyridine - chloranilic acid (1:1) are discussed in more details. A 14N NQR study of the strong short O-HKN hydrogen bond in two polymorphic forms of cocrystal isonicotinamide-oxalic acid (2:1) is presented as well. Various correlations between the NQR parameters and between the NQR and structural parameters have been observed. These correlations may be used to determine the proton position in a hydrogen bond and some other structural parameters from the NQR data.

  18. Temperature dependence of the quadrupole interaction of69Ge Tl and113Sn Sn

    NASA Astrophysics Data System (ADS)

    Semmler, W.; Raghavan, P.; Senba, M.; Raghavan, R. S.

    1981-03-01

    The quadrupole interaction constants of69Ge T1 and113Sn Sn were measured by means of the perturbed angular distribution technique as a function of temperature in the range of 80K≦T≦508 K and 80K≦T≦480 K, respectively. Isomeric states in69Ge and113Sn were populated by the heavy ion reactions56Fe(16O, 2 p n) and100Mo(16O, 3 n) and recoil implanted into polycrystalline Tl- and single crystalline Sn-backings. In the case of113Sn Sn, where the quadrupole coupling is weak, a special single crystal geometry was employed to enhance the sensitivity of the measurement. Within the limits of the errors the temperature dependence for both systems follows the empirical T1.5-dependence. While a strong temperature dependence comparable to In In is observed for69Ge T1, that for113Sn Sn is weaker than expected. The strength of the temperature dependence for113Sn Sn does not agree with the predictions of a lattice vibration model proposed recently for the temperature dependence of the quadrupole interaction.

  19. Analysis of manifestation of strong quadrupole light-molecule interaction in the SEHR spectra

    SciTech Connect

    Polubotko, A. M.

    2011-11-15

    It is demonstrated that appearance of strong lines in surface-enhanced hyper-Raman (SEHR) spectra of phenazine and pyrazine, which are associated with totally symmetric vibrations, as well as other details of these spectra, can be explained using the dipole-quadrupole theory. The main point of this theory is the concept of strong quadrupole interaction of light with molecules, which arises in surface fields strongly varying in space near a rough metal surface. The theoretical results make it possible to correctly interpret the SEHR spectra of phenazine and pyrazine (namely, the emergence of the strong lines due to totally symmetric vibrations that are forbidden in usual hyper-Raman scattering), as well as other lines in the spectrum.

  20. Nitrogen Nuclear Quadrupole Interactions in RDX, β-HMX and Cocaine Systems

    NASA Astrophysics Data System (ADS)

    Pati, Ranjit; Das, T. P.; Sahoo, N.; Ray, S. N.

    1997-03-01

    Using the Hartree-Fock-Roothaan procedure, the nuclear quadrupole interactions (NQI) of the 14N (I = 1) nucleus in the energetically important molecules RDX, β-HMX and the physiologically important molecule Cocaine, are studied. The coupling constants (e2 q Q) and asymmetry parameters (η) for the three ring nitrogens in RDX are found to be -5.671, -5.808 and -5.838 MHz and 0.542, 0.556 and 0.562, respectively, in good quantitative agreement with the experimental results of 5.735, 5.799 and 5.604 MHz for the magnitudes of e2qQ and 0.6215, 0.6146 and 0.6024 for η obtained in the single crystal. For β-HMX, where two sets of e2 q Q and η are expected from symmetry considerations, our calculated values are -5.936 and -6.069 MHz for e2 q Q and 0.432 and 0.490 for η , compared to experimentally measured magnitudes of 5.791 and 6.025 MHz and η-values of 0.4977 and 0.5180, respectively, obtained in the single crystal. For Cocaine free base which contains only one 14N nucleus, our calculated values of e2 qQ and η are -5.038 MHz and 0.067, in very good agreement with the experimental results of 5.0229 MHz for the magnitude of e2 q Q and 0.0395 for η. Possible reasons for the small remaining differences between theory and experiment in e2 q Q and η for all three systems and the significant differences in trends over the three nitrogens in RDX between theory and experiment are discussed. Also, the calculated quadrupole interaction parameters for the 14N nuclei in the NO2 groups outside the ring for both RDX and β-HMX are presented with the hope that they will be measured in the future to provide a more complete understanding of the electron distributions in these systems.

  1. Radiation and Thermal Analysis of Superconducting Quadrupoles in the Interaction Region of Linear Collider

    SciTech Connect

    Drozhdin, A.I.; Kashikhin, V.V.; Kashikhin, V.S.; Lopes, M.L.; Mokhov, N.V.; Zlobin, A.V.; Seryi, Andrei; /SLAC

    2011-10-14

    Radiation heat deposition in the superconducting magnets of the Interaction Region (IR) of a linear collider can be a serious issue that limits the magnet operating margins and shortens the material lifetime. Radiation and thermal analyses of the IR quadrupoles in the incoming and extraction beam lines of the ILC are performed in order to determine the magnet limits. This paper presents an analysis of the radial, azimuthal and longitudinal distributions of heat deposition in the incoming and disrupted beam doublets. Operation margins of the magnets based on NbTi superconductor are calculated and compared. The radiation and thermal analysis of the ILC IR quadrupoles based on Rutherford type cables was performed. It was found that the peak radiation heat deposition takes place in the second extraction quadrupole QFEX2. The maximum power density in the coil is {approx}17mW/g. This is rather high, comparing to the proton machines (LHC). However, the fast radial decay of the heat deposition together with the high thermal conductivity of the Rutherford type cable limits the coil temperatures to a moderate level. It was determined that both 2-layer and 4-layer QFEX2 magnet designs have thermal margins of a factor of {approx}4 at the nominal gradient of 31.3 T/m. Because of the large margins, these magnets can easily accommodate possible changes in the IR optics and heat deposition levels.

  2. Reconstruction of nuclear quadrupole interaction in (In,Ga)As/GaAs quantum dots observed by transmission electron microscopy

    NASA Astrophysics Data System (ADS)

    Sokolov, P. S.; Petrov, M. Yu.; Mehrtens, T.; Müller-Caspary, K.; Rosenauer, A.; Reuter, D.; Wieck, A. D.

    2016-01-01

    A microscopic study of the individual annealed (In,Ga)As/GaAs quantum dots is done by means of high-resolution transmission electron microscopy. The Cauchy-Green strain-tensor component distribution and the chemical composition of the (In,Ga)As alloy are extracted from the microscopy images. The image processing allows for the reconstruction of the strain-induced electric-field gradients at the individual atomic columns extracting thereby the magnitude and asymmetry parameter of the nuclear quadrupole interaction. Nuclear magnetic resonance absorption spectra are analyzed for parallel and transverse mutual orientations of the electric-field gradient and a static magnetic field.

  3. Study of a micro chamber quadrupole mass spectrometer

    SciTech Connect

    Wang Jinchan; Zhang Xiaobing; Mao Fuming; Xiao Mei; Cui Yunkang; Engelsen, Daniel den; Lei Wei

    2008-03-15

    The design of a micro chamber quadrupole mass spectrometer (MCQMS) having a small total volume of only 20 cm{sup 3}, including Faraday cup ion detector and ion source, is described. This MCQMS can resist a vacuum baking temperature of 400-500 deg. C. The quadrupole elements with a hyperbolic surface are made of a ceramic material and coated with a thin metal layer. The quadrupole mass filter has a field radius of 3 mm and a length of 100 mm. Prototypes of this new MCQMS can detect a minimum partial pressure of 10{sup -8} Pa, have a peak width of {delta}M=1 at 10% peak height from mass number 1 to 60, and show an excellent long-term stability. The new MCQMS is intended to be used in residual gas analyses of electron devices during a mutual pumping and baking process.

  4. Discriminating the structure of exo-2-aminonorbornane using nuclear quadrupole coupling interactions.

    PubMed

    Écija, Patricia; Cocinero, Emilio J; Lesarri, Alberto; Millán, Judith; Basterretxea, Francisco; Fernández, José A; Castaño, Fernando

    2011-04-28

    The intrinsic conformational and structural properties of the bicycle exo-2-aminonorbornane have been probed in a supersonic jet expansion using Fourier-transform microwave (FT-MW) spectroscopy and quantum chemical calculations. The rotational spectrum revealed two different conformers arising from the internal rotation of the amino group, exhibiting small (MHz) hyperfine patterns originated by the (14)N nuclear quadrupole coupling interaction. Complementary ab initio (MP2) and DFT (B3LYP and M05-2X) calculations provided comparative predictions for the structural properties, rotational and centrifugal distortion data, hyperfine parameters, and isomerization barriers. Due to the similarity of the rotational constants, the structural assignment of the observed rotamers and the calculation of the torsion angles of the amino group were based on the conformational dependence of the (14)N nuclear quadrupole coupling hyperfine tensor. In the most stable conformation (ss), the two amino N-H bonds are staggered with respect to the adjacent C-H bond. In the second conformer (st), only one of the N-H bonds is staggered and the other is trans. A third predicted conformer (ts) was not detected, consistent with a predicted conformational relaxation to conformer ss through a low barrier of 5.2 kJ mol(-1).

  5. Theory for ^77Se and ^125Te Nuclear Quadrupole Interactions in Selenium and Tellurium.

    NASA Astrophysics Data System (ADS)

    Suck-Cho, Hwa; Oh, Young-Kee; Park, Jin-Ho; Das, T. P.

    1998-03-01

    The electric field gradient(efg) tensors at ^77Se and ^125Te nuclei have been studied for the four systems involving each of these nuclei in both Selenium and Tellurium crystals utilizing the first principles Hartee-Fock Cluster procedure. Using the calculated efg for the pure systems and the experimental quadrupole coupling constants (e^2qQ), the quadrupole moments are determined to be Q(^77Se)=0.74±0,07(b) and Q(^125Te)=0.35±0.04(b). Comparison will be made with earlier values for the Q of the two nuclei. Using our values of Q and the calculated efg for ^77Se in tellurium and ^125Te in selenium, our values of e^2qQ agree within 15 per cent with that of experiment. The asymmetry parametrs η also agree reasonably well with experiment, but not as closely as the e^2qQ. Experimental results for η for ^125Te in selenium are needed to compare with theory.

  6. Bound states for a Coulomb-type potential induced by the interaction between a moving electric quadrupole moment and a magnetic field

    SciTech Connect

    Bakke, K.

    2014-02-15

    We discuss the arising of bound states solutions of the Schrödinger equation due to the presence of a Coulomb-type potential induced by the interaction between a moving electric quadrupole moment and a magnetic field. Furthermore, we study the influence of the Coulomb-type potential on the harmonic oscillator by showing a quantum effect characterized by the dependence of the angular frequency on the quantum numbers of the system, whose meaning is that not all values of the angular frequency are allowed. -- Highlights: • Interaction between a moving electric quadrupole moment and a magnetic field. • Arising of bound states solutions due to the presence of a Coulomb-type potential. • Influence of the Coulomb-type potential on the harmonic oscillator. • Dependence of the angular frequency on the quantum numbers of the system.

  7. A higher level ab initio quantum-mechanical study of the quadrupole moment tensor components of carbon dioxide

    NASA Astrophysics Data System (ADS)

    Glaser, R.; Wu, Z.; Lewis, M.

    2000-12-01

    The quadrupolarity of carbon dioxide has been studied with higher level ab initio methods. Carbon dioxide exhibits {- + -} quadrupolarity in all directions and an explanation is provided of the origin of the sign of the diagonal elements Qii. The quadrupole moment tensor has been computed using restricted Hartree-Fock theory, second-order Møller-Plesset perturbation theory and quadratic configuration interaction theory. A variety of basis sets have been employed up to basis sets of the type [5s, 4p, 2d, 1f] (23s, 8p, 2d, 1f). The quadrupole moment tensor component Q∥ of carbon dioxide falls in the range between -18.5 and -20.5 Debye Å. The quadrupole moment tensor components Q⊥ of carbon dioxide are smaller, ranging from -14.5 to -15 Debye Å, and they are less sensitive to the choice of the theoretical model. The correlated methods consistently predict an increase of Q∥ while they predict a more modest reduction of Q⊥. It is for the opposing electron correlation effects on Q∥ and Q⊥ that the average values of the diagonal elements, , are essentially independent of the method and exhibit only a small variation depending on the basis set. On the other hand, the anisotropy of the quadrupolarity, the quadrupole moment Θ, is affected most by the opposing electron correlation effects on Q∥ and Q⊥. The accurate reproduction of the measured quadrupolarity Θ=-4.3 Debye Å requires a theoretical model that employs both a good method and a good basis set. The results suggest that the use of second-order Møller-Plesset perturbation theory in conjunction with well-polarized triple-ζ basis sets provides a cost-effective and quite accurate method for the estimation of correlation effects on quadrupole moments.

  8. Accurate ab initio calculations of the quadrupole moment of acetylene. A combined study of basis set, correlation, and vibrational effects

    NASA Astrophysics Data System (ADS)

    Lindh, R.; Liu, B.

    1991-03-01

    The quadrupole moment of acetylene has been studied at the multiconfiguration self-consistent field (MCSCF) and multireference single and double configuration interaction (MRSDCI) level of theory. At the MCSCF level the π-CI complete active space SCF (CASSCF) and the valence-CI CASSCF were employed. The subsequent MRSDCI calculations were continued until the reference space included all configuration state functions (CSFs) of the MCSCF wave function with a coefficient larger than 0.01 [MRSDCI(0.01)]. The higher level basis sets in this study were all based on van Duijneveldt's C(13s 8p) and H(6s) and extensions of that basis set. The study shows in a consistent way that both the one- and n-particle spaces are saturated at the highest level of theory. The study has revealed that in addition to the well known increase of the quadrupole moment due to the inclusion of polarizing functions in the basis (typically 0.20 a.u.), the inclusion of electronic correlation in the model wave function as well as vibrational corrections will decrease the quadrupole moment significantly more, -0.66, -0.49, and -0.36 a.u., for the correlation correction and zero-point correction for HCCH and DCCD, respectively. The most accurate computations predict the quadrupole moment of HCCH, including zero-point correction, to be 4.29±0.12 a.u., which discriminates the experimental estimates of 4.03±0.30, 4.28±0.30, and 4.57±0.30 a.u. (the first being the favored value). The quadrupole moment of DCCD is computed to 4.42±0.10 a.u. In the study it was observed that in contradiction to previous experiences the use of the model equilibrium geometries rather than the experimental geometry gives a smoother convergence as the level of theory is increased. The effects of basis set quality and electron correlation on the quadrupole moment are studied in detail. These effects are analyzed with reference to the redistribution of the electronic charge.

  9. Nuclear quadrupole resonance studies of amorphous, orthorhombic, and rhombohedral arsenic

    SciTech Connect

    Jellison, G.E. Jr.; Petersen, G.L.; Taylor, P.C.

    1980-10-15

    Pulsed nuclear quadrupole resonance (NQR) experiments have been performed on three forms of elemental arsenic: amorphous (a), rhombohedral (rh), and orthorhombic (or). The temperature dependence of the spin-lattice relaxation time (T/sub 1/) provides evidence for the existence of disorder (tunneling) modes in a-As. It is found that the NQR line shape of a-As is highly asymmetric, and this asymmetry is attributed to a distribution of dihedral angles in a-As. The observed NQR frequencies indicate that the amount of bonding s admixture is different in each material (rh-As:3%, or-As:7%, a-As:10%). Simple calculations in comparison with x-ray results indicate that the bonding configurations in these three forms of arsenic do not necessarily correspond to maximum overlap of bonding orbitals on adjacent atoms.

  10. Cat-state generation and stabilization for a nuclear spin through electric quadrupole interaction

    NASA Astrophysics Data System (ADS)

    Bulutay, Ceyhun

    2017-07-01

    Spin cat states are superpositions of two or more coherent spin states (CSSs) that are distinctly separated over the Bloch sphere. Additionally, the nuclei with angular momenta greater than 1/2 possess a quadrupolar charge distribution. At the intersection of these two phenomena, we devise a simple scheme for generating various types of nuclear-spin cat states. The native biaxial electric quadrupole interaction that is readily available in strained solid-state systems plays a key role here. However, the fact that built-in strain cannot be switched off poses a challenge for the stabilization of target cat states once they are prepared. We remedy this by abruptly diverting via a single rotation pulse the state evolution to the neighborhood of the fixed points of the underlying classical Hamiltonian flow. Optimal process parameters are obtained as a function of electric field gradient biaxiality and nuclear-spin angular momentum. The overall procedure is seen to be robust under 5% deviations from optimal values. We show that higher-level cat states with four superposed CSS can also be formed using three rotation pulses. Finally, for open systems subject to decoherence we extract the scaling of cat-state fidelity damping with respect to the spin quantum number. This reveals rates greater than the dephasing of individual CSSs. Yet, our results affirm that these cat states can preserve their fidelities for practically useful durations under the currently attainable decoherence levels.

  11. Nuclear quadrupole interaction of111Cd on type-1 Cu-sites in blue copper proteins

    NASA Astrophysics Data System (ADS)

    Tröger, W.; Butz, T.; Danielsen, E.; Bauer, R.; Thoenes, U.; Messerschmidt, A.; Huber, R.; Canters, G. W.; den Blaauwen, T.

    1993-03-01

    The nuclear quadrupole interaction (NQI) of111Cd substituted for Cu(II) on type-1 sites in blue copper proteins is characterized by high values of ω0 in the region of 300 Mrad/s, close to that for the catalytic zinc site in alcohol dehydrogenase. Type-1 Cu has usually two sulfur ligands and two nitrogen ligands and in some cases an oxygen ligand in either a distorted tetrahedral geometry or in a trigonal bipyramidal geometry. The near tetrahedral arrangement together with the ligand sphere containing the same number of sulfur ligands explains the value of ω0 in the blue copper proteins. The present work determined the partial NQI for methionine using the known structure of azurin. This value was then used in the angular overlap model to calculate the NQI for ascorbate oxidase the structure of which is also known and gave good agreement with experiment. NQI data for laccase and stellacyanin the structures of which are unknown, are also given.

  12. The temperature dependence of the nuclear quadrupole interaction of 44Ti(EC)44Sc in rutile

    NASA Astrophysics Data System (ADS)

    Butz, T.; Vianden, R.

    2013-05-01

    The temperature dependence of the Nuclear Quadrupole Interaction on 44Sc in rutile was measured by Time Differential Perturbed Angular Correlation in the temperature range from 300 K to 945 K. Whereas \\upomega _Q = eQV_zz/4hbar with Vzz denoting the largest component of the electric field gradient tensor in magnitude increases with increasing temperature, the asymmetry parameter η remains essentially constant. This observation fits into the systematic with other probes provided the sign of Vzz is negative.

  13. Hartree-Fock-Cluster Investigation of Nuclear Quadrupole Interactions in Solid Chalcogens, Selenium and Tellurium.

    NASA Astrophysics Data System (ADS)

    Aryal, M. M.; Maharjan, N. B.; Paudyal, D. D.; Mishra, D. R.; Byahut, S. R.; Scheicher, R. H.; Badu, S. R.; Jeong, J.; Chow, Lee; Das, T. P.

    2008-03-01

    Using the first-principles Hartree-Fock Cluster Procedure, we have studied the electronic structures of pure chain like Selenium and Tellurium, pure ring structured Selenium, Tellurium impurity in chain and ring-structured Selenium and Selenium impurity in chain-structured Tellurium chain. For our investigations in all the systems we have carried out convergence studies with respect to variational basis set sizes,sizes of clusters and electron correlation effects using many-body perturbation theory. Using our calculated electronic field-gradient parameters q in the pure chain systems and employing the experimental quadrupole coupling constants (e^2qQ), the values Q(^77Se)=(0.50±0.04) 10-28 m^2 and Q(^125Te)=-(0.2±0.02) 10-28m^2. Results will also be presented for the asymmetry parameters η for the pure chain systems and the e^2qQ and η for ^77Se in selenium ring. Our calculated values for e^2qQ and η for the impurity systems will also be presented and compared with available experimental data and earlier theoretical results.

  14. 57Fe quadrupole splitting and isomer shift in various oxyhemoglobins: study using Mössbauer spectroscopy

    NASA Astrophysics Data System (ADS)

    Oshtrakh, M. I.; Berkovsky, A. L.; Kumar, A.; Kundu, S.; Vinogradov, A. V.; Konstantinova, T. S.; Semionkin, V. A.

    2010-04-01

    A comparative study of normal human, rabbit and pig oxyhemoglobins and oxyhemoglobin from patients with chronic myeloleukemia and multiple myeloma using Mössbauer spectroscopy with a high velocity resolution demonstrated small variations of the 57Fe quadrupole splitting and isomer shift. These variations may be a result of small structural differences in the heme iron stereochemistry of various hemoglobins.

  15. Characterization of goat colostrum oligosaccharides by nano-liquid chromatography on chip quadrupole time-of-flight mass spectrometry and hydrophilic interaction liquid chromatography-quadrupole mass spectrometry.

    PubMed

    Martín-Ortiz, A; Salcedo, J; Barile, D; Bunyatratchata, A; Moreno, F J; Martin-García, I; Clemente, A; Sanz, M L; Ruiz-Matute, A I

    2016-01-08

    A detailed qualitative and quantitative characterization of goat colostrum oligosaccharides (GCO) has been carried out for the first time. Defatted and deproteinized colostrum samples, previously treated by size exclusion chromatography (SEC) to remove lactose, were analyzed by nanoflow liquid chromatography-quadrupole-time of flight mass spectrometry (Nano-LC-Chip-Q-TOF MS). Up to 78 oligosaccharides containing hexose, hexosamine, fucose, N-acetylneuraminic acid or N-glycolylneuraminic acid monomeric units were identified in the samples, some of them detected for the first time in goat colostra. As a second step, a hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC-MS) methodology was developed for the separation and quantitation of the main GCO, both acidic and neutral carbohydrates. Among other experimental chromatographic conditions, mobile phase additives and column temperature were evaluated in terms of retention time, resolution, peak width and symmetry of target carbohydrates. Narrow peaks (wh: 0.2-0.6min) and good symmetry (As: 0.8-1.4) were obtained for GCO using an acetonitrile:water gradient with 0.1% ammonium hydroxide at 40°C. These conditions were selected to quantify the main oligosaccharides in goat colostrum samples. Values ranging from 140 to 315mgL(-1) for neutral oligosaccharides and from 83 to 251mgL(-1) for acidic oligosaccharides were found. The combination of both techniques resulted to be useful to achieve a comprehensive characterization of GCO.

  16. Characterization of goat colostrum oligosaccharides by nano-liquid chromatography on chip quadrupole time-of-flight mass spectrometry and hydrophilic interaction liquid chromatography-quadrupole mass spectrometry

    PubMed Central

    Martín-Ortiz, A.; Salcedo, J.; Barile, D.; Bunyatratchata, A.; Moreno, F.J.; Martin-García, I.; Clemente, A.; Sanz, M.L.; Ruiz-Matute, A.I.

    2016-01-01

    A detailed qualitative and quantitative characterization of goat colostrum oligosaccharides (GCO) has been carried out for the first time. Defatted and deproteinized colostrum samples, previously treated by size exclusion chromatography (SEC) to remove lactose, were analyzed by nanoflow liquid chromatography-quadrupole-time of flight mass spectrometry (Nano-LC-Chip-Q-TOF MS). Up to 78 oligosaccharides containing hexose, hexosamine, fucose, N-acetylneuraminic acid or N-glycolylneuraminic acid monomeric units were identified in the samples, some of them detected for the first time in goat colostra. As a second step, a hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC-MS) methodology was developed for the separation and quantitation of the main GCO, both acidic and neutral carbohydrates. Among other experimental chromatographic conditions, mobile phase additives and column temperature were evaluated in terms of retention time, resolution, peak width and symmetry of target carbohydrates. Narrow peaks (wh: 0.2–0.6 min) and good symmetry (As: 0.8–1.4) were obtained for GCO using an acetonitrile:water gradient with 0.1% ammonium hydroxide at 40 °C. These conditions were selected to quantify the main oligosaccharides in goat colostrum samples. Values ranging from 140 to 315 mg L−1 for neutral oligosaccharides and from 83 to 251 mg L−1 for acidic oligosaccharides were found. The combination of both techniques resulted to be useful to achieve a comprehensive characterization of GCO. PMID:26427327

  17. Electrodynamical forbiddance of strong quadrupole light-molecule interaction and peculiarities of the SEHR spectra in the methane molecule

    NASA Astrophysics Data System (ADS)

    Chelibanov, V. P.; Polubotko, A. M.

    2014-07-01

    It is demonstrated that the strong quadrupole light-molecule interaction, which is responsible for the most enhancement of Surface Enhanced Hyper Raman Scattering (SEHRS), experiences so-called electrodynamical forbiddance in the methane molecule and molecules with cubic symmetry groups and does not influence on formation of the SEHRS spectra. This forbiddance results in the fact that the lines, caused by the totally symmetric vibrations, which are observed in pyrazine and phenazine, must be slight, or absent at all. In this case, in methane, the most enhanced lines are those, caused by vibrations, transforming after the irreducible representations T1 , or T2 .

  18. Quadrupole ion traps.

    PubMed

    March, Raymond E

    2009-01-01

    The extraordinary story of the three-dimensional radiofrequency quadrupole ion trap, accompanied by a seemingly unintelligible theoretical treatment, is told in some detail because of the quite considerable degree of commercial success that quadrupole technology has achieved. The quadrupole ion trap, often used in conjunction with a quadrupole mass filter, remained a laboratory curiosity until 1979 when, at the American Society for Mass Spectrometry Conference in Seattle, George Stafford, Jr., of Finnigan Corp., learned of the Masters' study of Allison Armitage of a combined quadrupole ion trap/quadrupole mass filter instrument for the observation of electron impact and chemical ionization mass spectra of simple compounds eluting from a gas chromatograph. Stafford developed subsequently the mass-selective axial instability method for obtaining mass spectra from the quadrupole ion trap alone and, in 1983, Finnigan Corp. announced the first commercial quadrupole ion trap instrument as a detector for a gas chromatograph. In 1987, confinement of ions generated externally to the ion trap was demonstrated and, soon after, the new technique of electrospray ionization was shown to be compatible with the ion trap. Copyright 2009 Wiley Periodicals, Inc.

  19. The Study of Single Nb3Sn Quadrupole Coils Using a Magnetic Mirror Structure

    SciTech Connect

    Chlachidze, G.; Andreev, N.; Barzi, E.; Bossert, R.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, N.; Novitski, I.; Orris, D.; Tartaglia, M.

    2010-07-30

    Several 90-mm quadrupole coils made of 0.7-mm Nb{sub 3}Sn strand based on the 'Restack Rod Process' (RRP) of 108/127 design, with cored and non-cored cables and different cable insulation, were fabricated and individually tested at Fermilab using a test structure designed to provide a quadrupole magnetic field environment. The coils were instrumented with voltage taps and strain gauges to study quench performance and mechanical properties. The Nb{sub 3}Sn strand and cable parameters, the coil fabrication details, the mirror model assembly procedure and test results at temperatures of 4.5 K and 1.9 K are reported and discussed.

  20. Vibration Measurements to Study the Effect of Cryogen Flow in Superconducting Quadrupole.

    SciTech Connect

    He,P.; Anerella, M.; aydin, S.; Ganetis, G. Harrison, M.; Jain, A.; Parker, B.

    2007-06-25

    The conceptual design of compact superconducting magnets for the International Linear Collider final focus is presently under development. A primary concern in using superconducting quadrupoles is the potential for inducing additional vibrations from cryogenic operation. We have employed a Laser Doppler Vibrometer system to measure the vibrations in a spare RHIC quadrupole magnet under cryogenic conditions. Some preliminary results of these studies were limited in resolution due to a rather large motion of the laser head as well as the magnet. As a first step towards improving the measurement quality, a new set up was used that reduces the motion of the laser holder. The improved setup is described, and vibration spectra measured at cryogenic temperatures, both with and without helium flow, are presented.

  1. Manifestation of a strong quadrupole interaction and peculiarities in the SERS and SEHRS spectra of 4,4'-bipyridine

    NASA Astrophysics Data System (ADS)

    Golovin, A. V.; Polubotko, A. M.

    2017-07-01

    The paper analyzes Surface Enhanced Raman Scattering (SERS) and Surface Enhanced Hyper Raman Scattering (SEHRS) spectra of 4,4'-bypiridine molecule for two possible geometries, which are described by D 2 and D 2 h symmetry groups. It is pointed out on appearance of sufficiently strong lines, caused by vibrations with the unit irreducible representation for both possible configurations. Appearance of these lines in the SEHRS spectrum points out the existence of a strong quadrupole light-molecule interaction. In addition one observes the lines, caused by vibrations both with the unit irreducible representations A or A g and the irreducible representation B 1 or B 1 u . The last ones describe transformational properties of the d z component of the dipole moment, which is perpendicular to the surface. This property of the spectrum is caused by peculiarity of the geometry of the molecule, which consists of two benzene rings, which are weakly connected with each other. The linear combinations of the vibrations of the rings create two nearly degenerated symmetric and anti symmetrical states, which cannot be identified in the experimental spectra. The result is in a full agreement with the dipole-quadrupole theory of SERS and SEHRS.

  2. Low-temperature nuclear quadrupole resonance studies of antimony and application to thermometry

    NASA Astrophysics Data System (ADS)

    Genio, Edgar Baylon

    1997-11-01

    The spin-lattice retaxation time, Tsb1, of finely divided powdered metallic antinomy immersed in liquid sp3He was measured using pulsed Nuclear Quadrupole Resonance (NQR) techniques. In this technique, the nuclear quadrupole resonant antinomy nuclei were saturated using an RF pulse. The recovery back to equilibrium was monitored using short inspection pulses and the magnetization recovery follows a recovery curve characterized by the relaxation time Tsb1. Tsb1 measurements were performed at temperatures ranging from 150 mK to 1.25 mK. Temperatures down to 11 mK were achieved by using a dilution refrigerator. Lower temperatures were achieved using adiabatic nuclear demagnetization of a copper bundle starting at 8.5 Tesla (7.5 Tesla average field over the copper bundle). The sample was cooled by immersion in liquid sp3He which is in thermal contact with silver sinter packed in the bottom of a silver cell. This cell was bolted onto a cold plate attached to the copper bundle. It was found that a low temperatures starting near 75 mK, the measured total relaxation was significantly enhanced with respect to the Korringa relaxation, the dominant relaxation mechanism expected for a metal at these temperatures. This enhancement is attributed to a surface relaxation mechanism mediated by the surface sp3He atoms. In systems immersed in liquid sp3He, a surface relaxation mechanism is present due to a modulation of the interaction between the solid-like sp3He atoms on the surface and the surface spins. This modulation is due to the quantum zero-point motion of the sp3He atoms on the surface. This phenomenon has been well studied in insulating systems using Nuclear Magnetic Resonance. The measurements undertaken in this study demonstrate that this phenomenon is present in a metallic and quadrupolar system. This surface relaxation mechanism becomes the dominant relaxation mechanism at low temperatures. Considering the surface and bulk spins as belonging to different phases, a two

  3. Mechanical Design Studies of the MQXF Long Model Quadrupole for the HiLumi LHC

    DOE PAGES

    Pan, Heng; Anderssen, Eric; Ambrosio, Giorgio; ...

    2016-12-20

    The Large Hadron Collider Luminosity upgrade (HiLumi) program requires new low-β triplet quadrupole magnets, called MQXF, in the Interaction Region (IR) to increase the LHC peak and integrated luminosity. The MQXF magnets, designed and fabricated in collaboration between CERN and the U.S. LARP, will all have the same cross section. The MQXF long model, referred as MQXFA, is a quadrupole using the Nb3Sn superconducting technology with 150 mm aperture and a 4.2 m magnetic length and is the first long prototype of the final MQXF design. The MQXFA magnet is based on the previous LARP HQ and MQXFS designs. Inmore » this paper we present the baseline design of the MQXFA structure with detailed 3D numerical analysis. A detailed tolerance analysis of the baseline case has been performed by using a 3D finite element model, which allows fast computation of structures modelled with actual tolerances. Tolerance sensitivity of each component is discussed to verify the actual tolerances to be achieved by vendors. In conclusion, tolerance stack-up analysis is presented in the end of this paper.« less

  4. Mechanical Design Studies of the MQXF Long Model Quadrupole for the HiLumi LHC

    SciTech Connect

    Pan, Heng; Anderssen, Eric; Ambrosio, Giorgio; Cheng, Daniel; Juchno, Mariusz; Ferracin, Paolo; Felice, Helene; Perez, Juan; Prestemon, Soren; Vallone, Giorgio

    2016-12-20

    The Large Hadron Collider Luminosity upgrade (HiLumi) program requires new low-β triplet quadrupole magnets, called MQXF, in the Interaction Region (IR) to increase the LHC peak and integrated luminosity. The MQXF magnets, designed and fabricated in collaboration between CERN and the U.S. LARP, will all have the same cross section. The MQXF long model, referred as MQXFA, is a quadrupole using the Nb3Sn superconducting technology with 150 mm aperture and a 4.2 m magnetic length and is the first long prototype of the final MQXF design. The MQXFA magnet is based on the previous LARP HQ and MQXFS designs. In this paper we present the baseline design of the MQXFA structure with detailed 3D numerical analysis. A detailed tolerance analysis of the baseline case has been performed by using a 3D finite element model, which allows fast computation of structures modelled with actual tolerances. Tolerance sensitivity of each component is discussed to verify the actual tolerances to be achieved by vendors. In conclusion, tolerance stack-up analysis is presented in the end of this paper.

  5. The impact of quadrupole moment of 4f shell on the hyperfine interactions anisotropy in RAl2 (R=Sm, Tb) intermetallic compounds

    NASA Astrophysics Data System (ADS)

    Delyagin, N. N.; Erzinkyan, A. L.

    2016-03-01

    The magnetic hyperfine interactions for 119Sn impurity atoms in SmAl2 and TbAl2 ferromagnetic compounds have been investigated by Mössbauer spectroscopy technique. These compounds have the same structure but differ in the sign of the quadrupole moment of the R3+ ion. In both cases, the spectrum contains two magnetic subspectra with the ratio of the intensities 1:3, which correspond to a and b Al sites with significantly different hyperfine parameters. The phenomenon change the order the component of inversion component of the Mössbauer spectra was found. This phenomenon is explained by the influence of the quadrupole moment 4f-shell of R3+ ions on the electron density distribution in the valence band. The degree of overlap of electron wave functions being on hybrid orbitals greatly depends on the sign of the 4f-shell quadrupole moment, which gives rise to huge anisotropy in the hyperfine magnetic field and the electric field gradient. Quadrupole deformation induced by the 4f quadrupole moment and the electric field gradient, greatly affects the d-like and p-like components of the electron wave functions, but little effect on the its s-components.

  6. Extended nuclear quadrupole resonance study of the heavy-fermion superconductor PuCoGa5

    NASA Astrophysics Data System (ADS)

    Koutroulakis, G.; Yasuoka, H.; Tobash, P. H.; Mitchell, J. N.; Bauer, E. D.; Thompson, J. D.

    2016-10-01

    PuCoGa5 has emerged as a prototypical heavy-fermion superconductor, with its transition temperature (Tc≃18.5 K) being the highest amongst such materials. Nonetheless, a clear description as to what drives the superconducting pairing is still lacking, rendered complicated by the notoriously intricate nature of plutonium's 5 f valence electrons. Here, we present a detailed Ga,7169 nuclear quadrupole resonance (NQR) study of PuCoGa5, concentrating on the system's normal state properties near to Tc and aiming to detect distinct signatures of possible pairing mechanisms. In particular, the quadrupole frequency and spin-lattice relaxation rate were measured for the two crystallographically inequivalent Ga sites and for both Ga isotopes, in the temperature range 1.6-300 K. No evidence of significant charge fluctuations is found from the NQR observables. On the contrary, the low-energy dynamics is dominated by anisotropic spin fluctuations with strong, nearly critical, in-plane character, which are effectively identical to the case of the sister compound PuCoIn5. These findings are discussed within the context of different theoretical proposals for the unconventional pairing mechanism in heavy-fermion superconductors.

  7. Extended nuclear quadrupole resonance study of the heavy-fermion superconductor PuCoGa5

    DOE PAGES

    Koutroulakis, Georgios; Yasuoka, Hiroshi; Tobash, Paul H.; ...

    2016-10-10

    PuCoGa5 has emerged as a prototypical heavy-fermion superconductor, with its transition temperature (Tc ≃ 18.5 K) being the highest amongst such materials. Nonetheless, a clear description as to what drives the superconducting pairing is still lacking, rendered complicated by the notoriously intricate nature of plutonium's 5f valence electrons. Here, we present a detailed 69,71Ga nuclear quadrupole resonance (NQR) study of PuCoGa5, concentrating on the system's normal state properties near to Tc and aiming to detect distinct signatures of possible pairing mechanisms. In particular, the quadrupole frequency and spin-lattice relaxation rate were measured for the two crystallographically inequivalent Ga sites andmore » for both Ga isotopes, in the temperature range 1.6–300 K. No evidence of significant charge fluctuations is found from the NQR observables. On the contrary, the low-energy dynamics is dominated by anisotropic spin fluctuations with strong, nearly critical, in-plane character, which are effectively identical to the case of the sister compound PuCoIn5. Lastly, these findings are discussed within the context of different theoretical proposals for the unconventional pairing mechanism in heavy-fermion superconductors.« less

  8. (14) N nuclear quadrupole resonance study of piroxicam: confirmation of new polymorphic form V.

    PubMed

    Lavrič, Zoran; Pirnat, Janez; Lužnik, Janko; Puc, Uroš; Trontelj, Zvonko; Srčič, Stane

    2015-06-01

    A new polymorphic crystal form of piroxicam was discovered while preparing crystalline samples of piroxicam for (14) N nuclear quadrupole resonance (NQR) analysis. The new crystal form, designated as V, was prepared by evaporative recrystallization from dichloromethane. Three known polymorphic forms (I, II, and III) were also prepared. Our aim was to apply (14) N NQR to characterize the new polymorphic form of piroxicam and compare the results with those of the other known polymorphic forms. Additional analytical methods used for characterization were X-ray powder diffraction (XRPD), thermal analysis, and vibrational spectroscopy. For the first time, a complete set of nine characteristic (14) N NQR frequencies was found for each prepared polymorph of piroxicam. The consistent set of measured frequencies and calculated characteristic quadrupole parameters found for the new polymorphic form V is a convincing evidence that we are dealing with a new form. The already known piroxicam polymorphic forms were characterized similarly. The XRPD results were in accordance with the conclusions of (14) N NQR analysis. The performed study clearly demonstrates a strong potential of (14) N NQR method to be applied as a highly discriminative spectroscopic analytical tool to characterize polymorphic forms.

  9. Studies of the four-rod RFQ (radio-frequency quadrupole) using the MAFIA codes

    SciTech Connect

    Browman, M.J.; Spalek, G.; Friedrichs, P.B.; Barts, T.C.

    1988-01-01

    A four-rod frequency quadrupole (RFQ) was studied using the MAFIA codes in the hoped of reducing the maximum power loss density, an important consideration for CW operation. The 389.9-MHz calculated frequency was within 2.1% of the 407.5-MHz measured value, and a study of the magnetic field patterns showed that the current flow, and hence power loss, was concentrated at the outer part of the rods. A simple modification of the rod shape reduced the power loss density in this region, which would ease the cooling problem. This modification, however, only improved the Q of the structure by about 1%, and further studies are needed to determine if the efficiency of the structure can be significantly improved. 4 refs., 9 figs.

  10. Crystallization of an amorphous solid studied by nuclear quadrupole double resonance

    NASA Astrophysics Data System (ADS)

    Seliger, Janez; Žagar, Veselko

    2013-06-01

    Nuclear quadrupole double resonance (NQDR) is proposed as a method for quantitative observation of crystallization of amorphous solids. NQDR signals from amorphous and crystalline parts of a sample may be separated. The intensity I of the NQDR signal from the crystalline part of the sample is proportional to its mass. With increasing time the amorphous phase in the sample transforms to the crystal phase and the intensity I approaches its limiting value I0 corresponding to the complete transformation to the crystal phase. The ratio I/I0 is equal to the mass fraction of the crystalline part of the sample. The same experimental method can be used to determine the mass fraction of a given crystal polymorph in a mixture of crystal polymorphs. As an example we studied crystallization of amorphous nifedipine at 100 °C. The results of the NQDR study are compared to the published results of other studies.

  11. ¹⁴N nuclear quadrupole resonance study of polymorphism in famotidine.

    PubMed

    Luźnik, Janko; Pirnat, Janez; Jazbinšek, Vojko; Lavrič, Zoran; Žagar, Veselko; Srčič, Stane; Seliger, Janez; Trontelj, Zvonko

    2014-09-01

    (14)N nuclear quadrupole resonance (NQR) in two known polymorphs of famotidine was measured. At room temperature, seven quadrupolar sets of transition frequencies (ν(+), ν(-), and ν(0)) corresponding to seven different nitrogen sites in the crystal structure of each of the two polymorphs were found. This confirms the expected ability of NQR to distinguish polymorph B from its analog A. NQR can also measure their ratio in a solid mixture and in the final dosage form, that is, a tablet. The NQR frequencies, line shapes, and tentative assignation to all seven molecular (14)N atoms were obtained. Unravelment of these two entangled NQR spectra presents a valuable contribution to the NQR database and enables studies of some possible correlations therein. Moreover, nondestructive (14)N NQR studies of commercial famotidine tablets can reveal some details of the drug fabrication process connected with compression. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. Accelerated simulation study of space charge effects in quadrupole ion traps using GPU techniques.

    PubMed

    Xiong, Xingchuang; Xu, Wei; Fang, Xiang; Deng, Yulin; Ouyang, Zheng

    2012-10-01

    Space charge effects play important roles in the performance of various types of mass analyzers. Simulation of space charge effects is often limited by the computation capability. In this study, we evaluate the method of using graphics processing unit (GPU) to accelerate ion trajectory simulation. Simulation using GPU has been compared with multi-core central processing unit (CPU), and an acceleration of about 390 times have been obtained using a single computer for simulation of up to 10(5) ions in quadrupole ion traps. Characteristics of trapped ions can be investigated at detailed levels within a reasonable simulation time. Space charge effects on the trapping capacities of linear and 3D ion traps, ion cloud shapes, ion motion frequency shift, mass spectrum peak coalescence effects between two ion clouds of close m/z are studied with the ion trajectory simulation using GPU.

  13. Accelerated Simulation Study of Space Charge Effects in Quadrupole Ion Traps Using GPU Techniques

    NASA Astrophysics Data System (ADS)

    Xiong, Xingchuang; Xu, Wei; Fang, Xiang; Deng, Yulin; Ouyang, Zheng

    2012-10-01

    Space charge effects play important roles in the performance of various types of mass analyzers. Simulation of space charge effects is often limited by the computation capability. In this study, we evaluate the method of using graphics processing unit (GPU) to accelerate ion trajectory simulation. Simulation using GPU has been compared with multi-core central processing unit (CPU), and an acceleration of about 390 times have been obtained using a single computer for simulation of up to 105 ions in quadrupole ion traps. Characteristics of trapped ions can be investigated at detailed levels within a reasonable simulation time. Space charge effects on the trapping capacities of linear and 3D ion traps, ion cloud shapes, ion motion frequency shift, mass spectrum peak coalescence effects between two ion clouds of close m/z are studied with the ion trajectory simulation using GPU.

  14. A study of solid propellant combustion using a triple quadrupole mass spectrometer with microprobe sampling

    SciTech Connect

    Litzinger, T.A.; Lee, Y.; Tank, C.J.

    1995-03-01

    RDX (1,3,5-trinitrohexahydro-s-triazine) is a highly energetic material which is used in solid propellants in rocket motors and artillery guns. While a substantial amount of literature has been published on RDX, its complicated combustion behavior, which involves chemical reactions in the solid, liquid and gas-phases, is not yet fully understood. In order to better understand the gas-phase chemical reactions of RDX and propellants with RDX as the primary ingredient, a study of the gas-phase chemistry of these materials has been undertaken using a triple quadrupole mass spectrometer and quartz microprobe sampling. In this abstract, after a summary of the experimental apparatus, results are presented for the analysis of masses 28, 29 and 30 as well as complete results for a typical test with RDX mono-propellant.

  15. Electric quadrupole moments and strong interaction effects in pionic atoms of /sup 165/Ho, /sup 175/Lu, /sup 176/Lu, /sup 179/Hf and /sup 181/Ta

    SciTech Connect

    Olaniyi, B.H.

    1980-01-01

    The effective quadrupole moments Q/sub eff/ of the nuclei of /sup 165/Ho, /sup 175/Lu, /sup 176/Lu, /sup 179/Hf and /sup 181/Ta were accurately measured by detecting the pionic atom 5g-4f x-rays of the elements. The spectroscopic quadrupole moments, Q/sub spec/, were obtained by correcting Q/sub eff/ for nuclear finite size effect, distortion of the pion wave function by the pion-nucleus strong interaction, and contribution to the energy level splittings by the strong interaction. The intrinsic quadrupole moments, Q/sub 0/, were obtained by projecting Q/sub spec/ into the frame of reference fixed on the nucleus. The shift, epsilon/sub 0/, and broadening, GAMMA/sub 0/, of the 4f energy level for all the elements were also measured. Theoretical values of epsilon/sub 0/ and GAMMA/sub 0/ were calculated and compared to the experimental values. The measured values of Q/sub 0/ were compared with existing results in muonic and pionic atoms. The measured values of epsilon/sub 0/ and GAMMA/sub 0/ were also compared with existing values.

  16. Electrodynamical forbiddance of strong quadrupole light-molecule interaction in the methane molecule and its manifestation in surface enhanced hyper Raman scattering spectra

    NASA Astrophysics Data System (ADS)

    Polubotko, A. M.

    2015-01-01

    It is demonstrated in the framework of the dipole-quadrupole theory that strong quadrupole light-molecule interaction, which is responsible for the most enhancement in SEHRS experiences a so- called electrodynamical forbiddance in the methane molecule, which belongs to the T d symmetry group, due to the electrodynamical law div E = 0 and does not infuence on the formation of the SEHRS spectra. This forbiddance results in the fact that the lines caused by totally symmetric vibrations transforming after the unit irreducible representation, which are observed in symmetrical molecules with another groups of sufficiently high symmetry, such as pyrazine and phenazine, must be small or absent at all. In this case, in methane, the most enhanced lines are those caused by the vibrations transforming after the irreducible representation F 2.

  17. Proton beam studies with a 1.25 MeV, cw radio frequency quadrupole linac

    SciTech Connect

    Bolme, G.O.; Hardek, T.W.; Hansborough, L.D.

    1998-12-31

    A high-current, cw linear accelerator has been proposed as a spallation neutron source driver for tritium production. Key features of this accelerator are high current (100 mA), low emittance-growth beam propagation, cw operation, high efficiency, and minimal maintenance downtime. A 268 MHz, cw radio frequency quadrupole (RFQ) LINAC section and klystrode based rf system were obtained from the Chalk River Laboratories and were previously installed at LANL to support systems development and advanced studies in support of cw, proton accelerators. A variation of the Low Energy Demonstration Accelerator (LEDA) proton injector, modified to operate at 50 keV, was mated to the RFQ and was operated to support advance developments for the Accelerator Production of Tritium (APT) program. High current, proton beam studies were completed which focused on the details of injector-RFQ integration, development of beam diagnostics, development of operations procedures, and personnel and equipment safety systems integration. This development led to acceleration of up to 100 mA proton beam.

  18. Rapid determination of amino acids in fruits of Ziziphus jujuba by hydrophilic interaction ultra-high-performance liquid chromatography coupled with triple-quadrupole mass spectrometry.

    PubMed

    Guo, Sheng; Duan, Jin-ao; Qian, Dawei; Tang, Yuping; Qian, Yefei; Wu, Dawei; Su, Shulan; Shang, Erxin

    2013-03-20

    In this study, a sensitive and rapid method for the simultaneous determination of free amino acids without derivatization using hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry (HILIC-MS/MS) was developed. The method was performed on an ultra-high-performance liquid chromatography (UHPLC) separation system coupled with a triple-quadrupole mass spectrometry (TQ-MS) instrument. Sufficient separation of 23 underivatized amino acids was achieved on an Acquity BEH Amide column (2.1 mm × 100 mm, 1.7 μm) in a single run of 12 min. Then the method was applied for the analysis of the free amino acids in 46 batches of Ziziphus jujuba fruits which comprised 39 cultivars from 26 cultivation regions. Multivariate statistical analysis was also used to investigate the differences in free amino acid profiles among the samples. This study showed that HILIC-UHPLC-TQ-MS is an effective technique to analyze underivatized amino acids in the food samples.

  19. Hydrophilic interaction ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry for determination of nucleotides, nucleosides and nucleobases in Ziziphus plants.

    PubMed

    Guo, Sheng; Duan, Jin-ao; Qian, Dawei; Wang, Hanqing; Tang, Yuping; Qian, Yefei; Wu, Dawei; Su, Shulan; Shang, Erxin

    2013-08-02

    In this study, a rapid and sensitive analytical method was developed for the determination of 20 nucleobases, nucleosides and nucleotides in Ziziphus plants at trace levels by using hydrophilic interaction ultra-high performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HILIC-UHPLC-TQ-MS/MS) in multiple-reaction monitoring (MRM) mode. Under the optimized chromatographic conditions, good separation for 20 target compounds were obtained on a UHPLC Amide column with sub-2μm particles within 10min. The overall LODs and LOQs were between 0.11-3.12ngmL(-1) and 0.29-12.48ngmL(-1) for the 20 analytes, respectively. It is the first report about simultaneous analysis of nucleobases, nucleosides and nucleotides in medicinal plants using HILIC-UHPLC-TQ-MS/MS method, which affords good linearity, precision, repeatability and accuracy. The developed method was successfully applied to Ziziphus plant (Z. jujuba, Z. jujuba var. spinosa and Z. mauritiana) samples. The analysis showed that the fruits and leaves of Ziziphus plants are rich in nucleosides and nucleobases as well as nucleotides, and could be selected as the healthy food resources. Our results in present study suggest that HILIC-UHPLC-TQ-MS/MS method could be employed as a useful tool for quality assessment of the samples from the Ziziphus plants as well as other medicinal plants or food samples using nucleotides, nucleosides and nucleobases as markers. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Degradation study of enniatins by liquid chromatography-triple quadrupole linear ion trap mass spectrometry.

    PubMed

    Serrano, A B; Meca, G; Font, G; Ferrer, E

    2013-12-15

    Enniatins A, A1, B and B1 (ENs) are mycotoxins produced by Fusarium spp. and are normal contaminants of cereals and derivate products. In this study, the stability of ENs was evaluated during food processing by simulation of pasta cooking. Thermal treatments at different incubation times (5, 10 and 15 min) and different pH (4, 7 and 10) were applied in an aqueous system and pasta resembling system (PRS). The concentrations of the targeted mycotoxins were determined using liquid chromatography coupled to tandem mass spectrometry. High percentages of ENs reduction (81-100%) were evidenced in the PRS after the treatments at 5, 10 and 15 min of incubation. In contrast to the PRS, an important reduction of the ENs was obtained in the aqueous system after 15 min of incubation (82-100%). In general, no significant differences were observed between acid, neutral and basic solutions. Finally, several ENs degradation products were identified using the technique of liquid chromatography-triple quadrupole linear ion trap mass spectrometry.

  1. Glass Structure by Scattering Methods and Spectroscopy — C. NUCLEAR QUADRUPOLE RESONANCE (NQR) STUDIES OF GLASS STRUCTURE

    NASA Astrophysics Data System (ADS)

    Bray, Philip J.

    The following sections are included: * Introduction * NMR Spectroscopy with Quadrupolar Effects * Zeeman and quadrupole interactions * First-order quadrupolar effects * Second-order quadrupolar effects * Case of a small asymmetry parameter * Case of a large(r) asymmetry parameter * Use of computer simulation to extract values of Qcc and η * Consequences of overlap of NMR spectra * NQR Spectroscopy * Genesis of spectra * Discovery of NQR * Instrumentation and procedures * NQR of particular nuclei in inorganic solids * 75As NQR * 11B NQR * 10B NQR * 27Al NQR * NQR of polymers * NQR with a Zeeman perturbation * Acknowledgments * References

  2. Classical Monte Carlo Study for Antiferro Quadrupole Orders in a Diamond Lattice

    NASA Astrophysics Data System (ADS)

    Hattori, Kazumasa; Tsunetsugu, Hirokazu

    2016-09-01

    We investigate antiferro quadrupole orders in a diamond lattice under magnetic fields by Monte Carlo simulations for two types of classical effective models. One is an XY model with Z3 anisotropy, and the other is a two-component ϕ4 model with a third-order anisotropy. We confirm that the universality class of the zero-field transition is that for the three-dimensional XY model. Magnetic field corresponds to a Z3 field in the effective model, and under this field, we find that collinear and canted antiferro-quadrupole orders compete. Each phase is characterized by symmetry breaking in the sector of (sublattice Z2) otimes (reflection Z2 for the order parameter). When Z3 anisotropy and magnetic field vary, it turns out that this system is a good playground for various multicritical points; bicritical and tetracritical points emerge in a finite field. Another important finding is about the scaling of parasitic ferro quadrupole order at the zero-field critical point. This is the secondary order parameter induced by the primary antiferro order, and its critical exponent β' = 0.815 clearly differs from the expected value that is twice the value for the primary order parameter. The corresponding correlation length exponent is also different, ν' = 0.597(12). We also discuss relation of the present effective quadrupole models with the 3-state Potts model as well as implication to understanding of orbital orders in Pr-based 1-2-20 compounds.

  3. A theoretical study on directivity control of multiple-loudspeaker system with a quadrupole radiation pattern in low frequency range

    NASA Astrophysics Data System (ADS)

    Irwansyah, Kuse, Naoyuki; Usagawa, Tsuyoshi

    2017-08-01

    Directivity pattern of an ordinary loudspeaker becomes more directive at higher frequencies. However, because a single loudspeaker tends to radiate uniformly in all directions at low frequencies, reverberation from surrounding building walls may affect speech intelligibility when installing a multiple-loudspeaker system at crossroads. As an alternative, a sharply directive sound source is recommended to be used, but in many cases the directivity of an ordinary loudspeaker is less sharp at lower frequencies. Therefore, in order to overcome such a limitation, this paper discusses the possibility of using four loudspeakers under active control to realize a quadrupole radiation pattern in low frequency range. In this study, the radiation pattern of a primary loudspeaker and three secondary loudspeakers has been modelled. By placing the loudspeakers close together in the direction of 0°, 90°, 180°, and 270°, it was theoretically demonstrated that a quadrupole radiation pattern can be shaped in the target frequency range up to 600 Hz by simply controlling the directivity in three of four directions which are 45°, 135°, 225°, and 315°. Although, the radiation pattern model is far from realistic configurations and conditions, it is possible to realize a quadrupole radiation pattern in the low frequency range.

  4. Magnetic Nanoparticle Drug Carriers and their Study by Quadrupole Magnetic Field-Flow Fractionation

    PubMed Central

    Williams, P. Stephen; Carpino, Francesca; Zborowski, Maciej

    2009-01-01

    Magnetic nanoparticle drug carriers continue to attract considerable interest for drug targeting in the treatment of cancers and other pathological conditions. The efficient delivery of therapeutic levels of drug to a target site while limiting nonspecific, systemic toxicity requires optimization of the drug delivery materials, the applied magnetic field, and the treatment protocol. The history and current state of magnetic drug targeting is reviewed. While initial studies involved micron-sized and larger carriers, and work with these microcarriers continues, it is the sub-micron carriers or nanocarriers that are of increasing interest. An aspect of magnetic drug targeting using nanoparticle carriers that has not been considered is then addressed. This aspect involves the variation in the magnetic properties of the nanocarriers. Quadrupole magnetic field-flow fractionation (QMgFFF) is a relatively new technique for characterizing magnetic nanoparticles. It is unique in its capability of determining the distribution in magnetic properties of a nanoparticle sample in suspension. The development and current state of this technique is also reviewed. Magnetic nanoparticle drug carriers have been found by QMgFFF analysis to be highly polydisperse in their magnetic properties, and the strength of response of the particles to magnetic field gradients is predicted to vary by orders of magnitude. It is expected that the least magnetic fraction of a formulation will contribute the most to systemic toxicity, and the depletion of this fraction will result in a more effective drug carrying material. A material that has a reduced systemic toxicity will allow higher doses of cytotoxic drugs to be delivered to the tumor with reduced side effects. Preliminary experiments involving a novel method of refining a magnetic nanoparticle drug carrier to achieve this result are described. QMgFFF is used to characterize the refined and unrefined material. PMID:19591456

  5. The UCLA Phi Factory detector, the integration of superconducting compensation solenoids and the final focus interaction region quadrupoles

    SciTech Connect

    Green, M.A. ); Cline, D.B. . Dept. of Physics)

    1992-06-01

    The proposed Phi Factory for the University of California at Los Angeles (UCLA) is a small 510 MeV electron-positron colliding beam storage ring with high luminosity (greater than 10{sup 32} CM{sup {minus}2} S{sup {minus}1}). In order to do high quality Phi physics, a particle detector system with a large solid angle (preferably greater than 98 percent ) is required. Particle detection and analysis will be done within a 0.5 tesla solenoidal magnetic field. The solenoidal field within the detector causes coupling between beam oscillations in the horizontal and vertical directions. Therefore, compensation solenoids are required to keep the circulating particle beams from seeing the effects of the field from the main detector solenoid. Since high luminosity and a large solid angle are required, the detectors and a pair of compensation solenoids must be integrated with the final focus quadrupoles within the detector straight section. This report describes the design of two tapered, 0.5 tesla, superconducting compensation solenoids which must go around six rare earth permanent final focus quadrupoles or six superconducting quadrupoles on either side of the beam collision point. A cryogenic cooling system for these two solenoids, which will be coupled with the cooling system for the primary detector solenoid, is also described.

  6. Fermilab Tevatron quadrupoles

    SciTech Connect

    Cooper, W.E.; Fisk, H.E.; Gross, D.A.; Lundy, R.A.; Schmidt, E.E.; Turkot, F.

    1983-03-01

    Details on the design, construction, and performance tests of Energy Saver/Doubler quadrupoles are presented along with recent data from the test of a special high gradient low beta prototype quadrupole.

  7. Study of a quadrupole ion trap with damping force by the two-point one block method.

    PubMed

    Seddighi Chaharborj, S; Phang, P S; Sadat Kiai, S M; Majid, Z A; Abu Bakar, M R; Fudziah, I

    2012-06-30

    The capabilities and performances of a quadrupole ion trap under damping force based on collisional cooling is of particular importance in high-resolution mass spectrometry and should be analyzed by Mathieu's differential solutions. These solutions describe the stability and instability of the ion's trajectories confined in quadrupole devices. One of the methods for solving Mathieu's differential equation is a two-point one block method. In this case, Mathieu's stability diagram, trapping parameters a(z) and q(z) and the secular frequency of the ion motion w(z), can be derived in a precise manner. The two-point one block method (TPOBM) of Adams Moulton type is presented to study these parameters with and without the effect of damping force and compared to the 5th-order Runge-Kutta method (RKM5). The simulated results show that the TPOBM is more accurate and 10 times faster than the RKM5. The physical properties of the confined ions in the r and z axes are illustrated and the fractional mass resolutions m/Δm of the confined ions in the first stability region were analyzed by the RKM5 and the TPOBM. The Lagrange interpolation polynomial was applied in the derivation of the proposed method. The proposed method will be utilized to obtain a series solution directly without reducing it to first order equations. The problem was tested with the ion trajectories in real time with and without the effect of damping force using constant step size. Numerical results from the two-point one block method have been compared with the fifth order Runge-Kutta method. The proposed two-point one block method has a potential application to solve complicated linear and nonlinear equations of the charged particle confinement in a quadrupole field especially in fine tuning accelerators, and, generally speaking, in physics of high energy. Copyright © 2012 John Wiley & Sons, Ltd.

  8. Mechanical Design of a Second Generation LHC IR Quadrupole

    SciTech Connect

    Caspi, S.; Bartlett, S.E.; Dietderich, D.R.; Ferracin, P.; Gourlay, S.A.; Hafalia, R.R.; Hannaford, C.R.; Lietzke, A.F.; McInturff,A.D.; Sabbi, G.; Scanlan, R.M.

    2003-11-10

    One of the proposed options to increase the LHC luminosity is the replacement of the existing inner triplets at the Interaction Regions with new low-beta larger aperture quadrupoles operating at the same gradient. Lawrence Berkeley National Laboratory (LBNL) is carrying out preliminary studies of a large-bore Nb{sub 3}Sn quadrupole. The mechanical design presents a support structure based on the use of keys and bladders without self-supporting collars. This technology has been proven effective in several successful common coil Nb{sub 3}Sn dipoles built at LBNL, and it is for the first time applied to a cos(2{var_theta}) design. In this paper we present a detailed analysis of the quadrupole mechanical behavior, demonstrating the possibility of delivering, through this method, well-controlled coil precompression during assembly, cool-down and excitation. The study has been performed with the finite element program ANSYS.

  9. Field Quality Study of the LARP Nb3Sn 3.7m-Long Quadrupole Models of LQ Series

    SciTech Connect

    AMbrosio, G.; Andreev, N.; Bossert, R.; Chlachidze, G.; DiMarco, J.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Prebys, E.; Sylvester, C.; Tartaglia, M.; /Fermilab /LBL, Berkeley /Brookhaven

    2011-09-01

    After the successful test of the first long Nb{sub 3}Sn quadrupole magnet (LQS01), the US LHC Accelerator Research Program (LARP) has assembled and tested a new 3.7 m-long Nb{sub 3}Sn quadrupole (LQS02). This magnet has four new coils made of the same conductor as LQS01 coils, and it is using the same support structure. LQS02 was tested at the Fermilab Vertical Magnet Test Facility with the main goal to confirm that the long models can achieve field gradient above 200 T/m, LARP target for 90-mm aperture, as well as to measure the field quality. These long models lack some alignment features and it is important to study the field harmonics. Previous field quality measurements of LQS01 showed higher than expected differences between measured and calculated harmonics compared to the short models (TQS) assembled in a similar structure. These differences could be explained by the use of two different impregnation fixtures during coil fabrication. In this paper, we present a comparison of the field quality measurements between LQS01 and LQS02 as well as a comparison with the short TQS models. If the result supports the coil fabrication hypothesis, another LQS assembly with all coils fabricated in the same fixture will be produced for understanding the cause of the discrepancy between short and long models.

  10. The Coriolis Interaction between the v2 = 1 and v3 = 2 States of Nitrosyl Bromide: Anomalous Quadrupole Patterns and Interstate Transitions in the Millimeter-Wave Spectrum.

    PubMed

    Esposti; Fuganti; Kisiel; Tamassia

    1998-10-01

    The millimeter-wave rotational spectra of 79BrNO and 81BrNO in the v2 = 1 and v3 = 2 vibrational states have been reinvestigated. Measurements of the rotational spectrum in the region of maximum c-type Coriolis interaction between the two states allowed the previous analysis to be extended to account for some uncommon effects. For the most perturbed transitions the nuclear quadrupole hyperfine structure arises from coupling of not only the bromine nucleus, but also the nitrogen nucleus with the rotational angular momentum. These effects were satisfactorily fitted with a Hamiltonian describing Coriolis coupling in a molecule with two quadrupolar nuclei. The successful analysis of pure rotational transitions then allowed accurate prediction of rovibrational transitions, six of which were measured for 79BrNO and four for 81BrNO. Copyright 1998 Academic Press.

  11. Electronic Structure and Nuclear Quadrupole Interactions in Cocaine Hydrochloride(C_17H_21NO_4HCl)

    NASA Astrophysics Data System (ADS)

    Pati, Ranjit; Sahoo, N.; Das, T. P.; Ray, S. N.

    1998-03-01

    The electronic structure of C_17H_21NO_4HCl has been investigated using the Hartree-Fock-Roothaan variational procedure. The position of the hydrogen atom, associated with HCl, which is not available from structural data, has been determined through total energy optimization with two likely positions obtained, one at 1.06 A from the nitrogen atom and the other at 1.73 A from the latter and 1.35 A from chlorine, these positions indicating bonding of H with nitrogen and chlorine respectively. The former position is found to be significantly more stable(about 0.54 eV) compared to the latter and leads to quadrupole coupling constants and asymmetry parameters of -1.422 MHz and 0.281 for the ^14N nucleus and -8.609 MHz and 0.146 for ^35Cl. These results are in good agreement with the corresponding experimental magnitudes(J. P. Yesinowski, M. L. Buess, A. N. Garroway, M. Ziegeweid and A. Pines, Analytical Chemistry 67), 2256 (1995). of 1.1780 MHz, 0.2632 and 5.027 MHz, 0.2, demonstrating that the correct picture in this compound is one of hydrogen leaving the chlorine and getting attached to nitrogen, as suggested earlier^1.

  12. A study of resonance electron capture ionization on a quadrupole tandem mass spectrometer.

    PubMed

    Wei, J; Liu, S; Fedoreyev, S A; Voinov, V G

    2000-01-01

    Procedures that allow the realization of resonance electron capture (REC) mode on a commercial triple-quadrupole mass spectrometer, after some simple modifications, are described. REC mass spectrometry (MS) and tandem mass spectrometry (MS/MS) experiments were performed and spectra for some compounds were recorded. In particular, the charge-remote fragmentation (CRF) spectra of [M - H](-) ions of docosanoic and docosenoic acids under low-energy collisionally activated dissociation (CAD) conditions were obtained, and showed that there were no significant differences for [M - H](-) ions produced at different resonances (i.e. for [M - H](-) ions with different structures). This observation was explained on the basis of results obtained from deuterium-labeled fatty acids, which showed that different CRF ions (but with the same m/z value in the absence of labels) could be produced by different mechanisms, and all of them were obviously realized under CAD conditions that made spectra practically indistinguishable. The other example, which compared the REC-MS/MS spectrum of [M - H](-) ions and EI-MS/MS spectrum of M(+.) ions of daidzein, demonstrated the potential of the REC-MS/MS technique for more complex structure elucidation.

  13. Nuclear quadrupole resonance study of local bonding in glassy As{sub x}Se{sub 1-x}

    SciTech Connect

    Ahn, Eungho; Williams, G. A.; Taylor, P. C.

    2006-11-01

    Nuclear quadrupole resonance (NQR) experiments were performed on glassy As{sub x}Se{sub 1-x} to study the local structural order. The bonding in As{sub x}Se{sub 1-x} is governed by preferential bonding (chemical ordering) between arsenic and selenium at arsenic concentrations x{<=}0.40; however, the bonding for higher arsenic concentrations is governed mostly by statistical considerations. At concentrations x{>=}0.45 the glasses are inhomogeneous with the presence of local regions of different composition. Measurements of the NQR spin echo intensity identify regions formed by arsenic atoms bonded to zero, one, two, or three selenium atoms. The NQR spectral line shapes and the longitudinal relaxation times suggest that these regions have a more ordered structure as compared to the homogeneous samples with low arsenic content. The existence of a small concentration of crystalline inclusions in amorphous As{sub 0.60}Se{sub 0.40} is also suggested.

  14. Nuclear-quadrupole-resonance study of overdoped Y1- xCaxBa2Cu3O7

    NASA Astrophysics Data System (ADS)

    Williams, G. V.; Krämer, S.; Mehring, M.

    2001-03-01

    We have performed a 63,65Cu nuclear-quadrupole-resonance study of overdoped Y1-xCaxBa2Cu3O7 and find that the temperature dependence of the Cu spin-lattice and spin-spin relaxation rates are similar to that in lightly overdoped YBa2Cu3O7. We show that the data can be interpreted within the Millis, Monien, and Pines model in terms of no significant decrease in the antiferromagnetic correlation length, at least for p<0.233. Furthermore, the isotopic ratios of the spin-lattice and spin-spin relaxation rates do not change with increasing hole concentration, indicating that magnetic relaxation is still dominant in the overdoped region.

  15. Study of the in vitro metabolism of TJ0711 using ultra high performance liquid chromatography with quadrupole time-of-flight and ultra fast liquid chromatography with quadrupole linear ion trap mass spectrometry.

    PubMed

    Hu, Lei; Lv, Zhenhua; Li, Gao; Xu, Xiaolong; Zhang, Chenghao; Cao, Peng; Huang, Jiangeng; Si, Luqin

    2015-06-01

    TJ0711 (1-[4-(2-methoxyethyl)phenoxy]-3-[2-(2-methoxyphenoxy)ethylamino]-2-propanol) is a novel β-adrenoreceptor blocker with vasodilating activity. The aim of this study was to investigate the in vitro metabolic properties of TJ0711 from both qualitative and quantitative aspects using mouse, rat, dog, and human liver microsomes as well as rat hepatocytes. Two modern liquid chromatography with tandem mass spectrometry systems, ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry and ultra fast liquid chromatography with quadrupole linear ion trap mass spectrometry, were utilized for the analysis. To better characterize the metabolic pathways of TJ0711, two major metabolites were incubated under the same conditions as that for TJ0711. TJ0711 was extensively metabolized in vitro, and a total of 34 metabolites, including 19 phase I and 15 phase II metabolites, were identified. Similar metabolite profiles were observed among species, and demethylation, hydroxylation, carboxylic acid formation, and glucuronidation were proposed as the major metabolic routes. Significant interspecies differences were observed in the metabolic stability studies of TJ0711. Furthermore, gender differences were significant in mice, rats, and dogs, but were negligible in humans. The valuable information provided in this work will be useful in planning and interpreting further pharmacokinetic, in vivo metabolism and toxicological studies of this novel β-blocker.

  16. QUADRUPOLE BEAM-BASED ALIGNMENT AT RHIC.

    SciTech Connect

    NIEDZIELA, J.; MONTAG, C.; SATOGATA, T.

    2005-05-16

    Successful implementation of a beam-based alignment algorithm, tailored to different types of quadrupoles at RHIC, provides significant benefits to machine operations for heavy ions and polarized protons. This algorithm was used to calibrate beam position monitor centers relative to interaction region quadrupoles to maximize aperture. This approach was also used to determine the optimal orbit through transition jump quadrupoles to minimize orbit changes during the transition jump for heavy ion acceleration. This paper provides background discussion and results from first measurements during the RHIC 2005 run.

  17. Nuclear quadrupole resonance studies of the SORC sequence and nuclear magnetic resonance studies of polymers

    SciTech Connect

    Jayakody, J.R.P.

    1993-12-31

    The behavior of induction signals during steady-state pulse irradiation in {sup 14}N NQR was investigated experimentally. Because Strong Off-resonance Comb (SORC) signals recur as long as the pulsing continues, very efficient signal-averaging can result. The dependence of these steady-state SORC signals on pulse parameters and on frequency offset are presented, together with a discussion of the applicability of the method. Also as part of the NQR work, cocaine base has been detected using conventional NQR techniques. The experimental results show that SORC detection can be of sufficient sensitivity to form the basis of narcotics screening devices for both mail and airline baggage. A new NMR technique, to obtain the correlation time of the random thermal motion of a polymer at temperatures near the glass transition has been introduced. The temperature dependence is a result of thermal motion. For slow-motion of a polymer chain near the glass transition, the CSA parameter begins to decrease. This motional narrowing can be interpreted to yield the correlation time of the thermal motion. In this work nitrocellulose isotopically highly enriched with {sup 15}N was studied at four different temperatures between 27{degrees} and 120{degrees} Celsius and the correlation times for polymer backbone motions were obtained. Naflon films containing water (D{sub 2}O and H{sub 2} {sup 17}O) and methanol (CH{sub 3}OD, CH{sub 3} {sup 17}OH), have been studied using deuteron and oxygen-17 NMR spectroscopy. Glassy behavior of the water domains at low temperature is evidenced by the specific nature of the {sup 2}H NMR lineshapes. Activation energies extracted from {sup 2}H spin-lattice relaxation data on the high temperature side of the T{sub 1} minimum exhibit a steady increase with increasing water content. In spite of a high degree of molecular mobility, angular-dependent spectra of both unstretched and stretched samples reflect considerable anisotrophy of the host polymer.

  18. Evolution of the one-phonon 21,ms+ mixed-symmetry state in N = 80 isotones as a local measure for the proton-neutron quadrupole interaction

    NASA Astrophysics Data System (ADS)

    Ahn, T.; Coquard, L.; Pietralla, N.; Rainovski, G.; Costin, A.; Janssens, R. V. F.; Lister, C. J.; Carpenter, M.; Zhu, S.; Heyde, K.

    2009-08-01

    An inverse kinematics Coulomb excitation experiment was performed to obtain absolute E2 and M1 transition strengths in 134Xe. The measured transition strengths indicate that the 23+ state of 134Xe is the dominant fragment of the one-phonon 21,ms+ mixed-symmetry state. Comparing the energy of the 21,ms+ mixed-symmetry state in 134Xe to that of the 21,ms+ levels in the N = 80 isotonic chain indicates that the separation in energy between the fully-symmetric 21+ state and the 21,ms+ level increases as a function of the number of proton pairs outside the Z = 50 shell closure. This behavior can be understood as resulting from the mixing of the basic components of a two-fluid quantum system. A phenomenological fit based on this concept was performed. It provides the first experimental estimate of the strength of the proton-neutron quadrupole interaction derived from nuclear collective states with symmetric and antisymmetric nature.

  19. Laser Desorption Ionization of As2Ch3 (Ch = S, Se, and Te) Chalcogenides Using Quadrupole Ion Trap Time-of-Flight Mass Spectrometry: A Comparative Study

    NASA Astrophysics Data System (ADS)

    Mawale, Ravi Madhukar; Ausekar, Mayuri Vilas; Prokeš, Lubomír; Nazabal, Virginie; Baudet, Emeline; Halenkovič, Tomáš; Bouška, Marek; Alberti, Milan; Němec, Petr; Havel, Josef

    2017-08-01

    Laser desorption ionization using time-of-flight mass spectrometer afforded with quadrupole ion trap was used to study As2Ch3 (Ch = S, Se, and Te) bulk chalcogenide materials. The main goal of the study is the identification of species present in the plasma originating from the interaction of laser pulses with solid state material. The generated clusters in both positive and negative ion mode are identified as 10 unary (S p +/- and As m +/- ) and 34 binary (As m S p +/- ) species for As2S3 glass, 2 unary (Se q +/- ) and 26 binary (As m Se q +/- ) species for As2Se3 glass, 7 unary (Te r +/- ) and 23 binary (As m Te r +/- ) species for As2Te3 material. The fragmentation of chalcogenide materials was diminished using some polymers and in this way 45 new, higher mass clusters have been detected. This novel approach opens a new possibility for laser desorption ionization mass spectrometry analysis of chalcogenides as well as other materials. [Figure not available: see fulltext.

  20. Monopole, Quadrupole and Pairing: a Shell Model View

    NASA Astrophysics Data System (ADS)

    Zuker, A. P.

    The three main contributions to the nuclear Hamiltonian-monopole, quadrupole and pairing - are analyzed in a shell model context. The first has to be treated phenomenologically, while the other two can be reliably extracted from the realistic interactions. Due to simple scaling properties, the realistic quadrupole and pairing interactions eliminate the tendency to collapse of their conventional counterparts, while retaining their basic simplicity.

  1. Superconducting magnetic quadrupole

    SciTech Connect

    Kim, J.W.; Shepard, K.W.; Nolen, J.A.

    1995-08-01

    A design was developed for a 350 T/m, 2.6-cm clear aperture superconducting quadrupole focussing element for use in a very low q/m superconducting linac as discussed below. The quadrupole incorporates holmium pole tips, and a rectangular-section winding using standard commercially-available Nb-Ti wire. The magnet was modeled numerically using both 2D and 3D codes, as a basis for numerical ray tracing using the quadrupole as a linac element. Components for a prototype singlet are being procured during FY 1995.

  2. A systematic investigation of hydrogen-bonding effects on the 17O, 14N, and 2H nuclear quadrupole resonance parameters of anhydrous and monohydrated cytosine crystalline structures: a density functional theory study.

    PubMed

    Mirzaei, Mahmoud; Elmi, Fatemeh; Hadipour, Nasser L

    2006-06-08

    A systematic computational study was carried out to characterize the 17O, 14N, and 2H nuclear quadrupole resonance (NQR) parameters in the anhydrous and monohydrated cytosine crystalline structures. To include the hydrogen-bonding effects in the calculations, the most probable interacting molecules with the central molecule in the crystalline phase were considered in the pentameric clusters of both structures. To calculate the parameters, couples of the methods B3LYP and B3PW91 and the basis sets 6-311++G** and CC-pVTZ were employed. The mentioned methods calculated reliable values of 17O, 14N, and 2H NQR tensors in the pentameric clusters, which are in good agreements with the experiment. The different influences of various hydrogen-bonding interactions types, N-H...N, N-H...O, and O-H...O, were observed on the 17O, 14N, and 2H NQR tensors. Lower values of quadrupole coupling constants and higher values of asymmetry parameters in the crystalline monohydrated cytosine indicate the presence of stronger hydrogen-bonding interactions in the monohydrated form rather than that of crystalline anhydrous cytosine.

  3. Quadrupole-bound anions: efficacy of positive versus negative quadrupole moments.

    PubMed

    Garrett, W R

    2012-02-07

    A pseudopotential method is utilized to study the critical stability of model anions formed by long-range quadrupolar molecular potentials. Results indicate that critical quadrupole moments of simple point-charge triads do not serve well as predictors of real quadrupole-bound anions of systems with negative moments.

  4. Integral Equation theory of a system of nematic quadrupoles

    NASA Astrophysics Data System (ADS)

    Mandal, Biplab kumar; Kumar, Anupam; Mishra, Pankaj

    2016-10-01

    We have studied a system of nematic quadrupoles interacting via inverse power potential of the form U ≈ (σ/r)5 (σ is the diameter of the particles and r is the separation between them), both in 3-dimension and 2-dimension. Pair correlation function has been calculated by solving Rogers-Young (RY) integral equation theory. Thermodynamic consistency has been obtained ensuring the equality of pressure calculated by virial and compressibility routes.

  5. Clusterization and quadrupole deformation in nuclei

    SciTech Connect

    Cseh, J.; Algora, A.; Antonenko, N. V.; Jolos, R. V.; Scheid, W.; Darai, J.; Hess, P. O.

    2006-04-26

    We study the interrelation of the clusterization and quadrupole deformation of atomic nuclei, by applying cluster models. Both the energetic stability and the exclusion principle is investigated. Special attention is paid to the relative orientations of deformed clusters.

  6. Correcting Quadrupole Roll in Magnetic Lenses with Skew Quadrupoles

    SciTech Connect

    Walstrom, Peter Lowell

    2014-11-10

    Quadrupole rolls (i.e. rotation around the magnet axis) are known to be a significant source of image blurring in magnetic quadrupole lenses. These rolls may be caused by errors in mechanical mounting of quadrupoles, by uneven radiation-induced demagnetization of permanent-magnet quadrupoles, etc. Here a four-quadrupole ×10 lens with so-called ”Russian” or A -B B-A symmetry is used as a model problem. Existing SLAC 1/2 in. bore high-gradient quadrupoles are used in the design. The dominant quadrupole roll effect is changes in the first-order part of the transfer map (the R matrix) from the object to the image plane (Note effects on the R matrix can be of first order in rotation angle for some R-matrix elements and second order in rotation angle for other elements, as shown below). It is possible to correct roll-induced image blur by mechanically adjusting the roll angle of one or more of the quadrupoles. Usually, rotation of one quadrupole is sufficient to correct most of the combined effect of rolls in all four quadrupoles. There are drawbacks to this approach, however, since mechanical roll correction requires multiple entries into experimental area to make the adjustments, which are made according to their effect on images. An alternative is to use a single electromagnetic skew quadrupole corrector placed either between two of the quadrupoles or after the fourth quadrupole (so-called “non-local” correction). The basic feasibility of skew quadrupole correction of quadrupole roll effects is demonstrated here. Rolls of the third lens quadrupole of up to about 1 milliradian can be corrected with a 15 cm long skew quadrupole with a gradient of up to 1 T/m. Since the effect of rolls of the remaining three lens quadrupoles are lower, a weaker skew quadrupole can be used to correct them. Non-local correction of quadrupole roll effects by skew quadrupoles is shown to be about one-half as effective as local correction (i.e. rotating individual quadrupoles to zero

  7. Study of magnetic particles pulse-injected into an annular SPLITT-like channel inside a quadrupole magnetic field.

    PubMed

    Hoyos, M; Moore, L R; McCloskey, K E; Margel, S; Zuberi, M; Chalmers, J J; Zborowski, M

    2000-12-01

    Advantages of the continuous magnetic flow sorting for biomedical applications over current, batch-wise magnetic separations include high throughput and a potential for scale-up operations. A continuous magnetic sorting process has been developed based on the quadrupole magnetic field centered on an annular flow channel. The performance of the sorter has been described using the conceptual framework of split-flow thin (SPLITT) fractionation, a derivative of field-flow fractionation (FFF). To eliminate the variability inherent in working with a heterogenous cell population, we developed a set of monodisperse magnetic microspheres of a characteristic magnetization, and a magnetophoretic mobility, similar to those of the cells labeled with a magnetic colloid. The theory of the magnetic sorting process has been tested by injecting a suspension of the magnetic beads into the carrier fluid flowing through the sorter and by comparing the theoretical and experimental recovery versus total flow-rate profiles. The position of the recovery maxima along the total flow-rate axis was a function of the average bead magnetophoretic mobility and the magnetic field intensity. The theory has correctly predicted the position of the peak maxima on the total flow-rate axis and the dependence on the bead mobility and the field intensity, but has not correctly predicted the peak heights. The differences between the calculated and the measured peak heights were a function of the total flow-rate through the system, indicating a fluid-mechanical origin of the deviations from the theory (such as expected of the lift force effects in the system). The well-controlled elution studies using the monodisperse magnetic beads, and the SPLITT theory, provided us with a firm basis for the future sorter evaluation using cell mixtures.

  8. SU(6) quadrupole phonon model for even and odd nuclei and the SU(3) limit

    NASA Astrophysics Data System (ADS)

    Paar, V.; Brant, S.; Canto, L. F.; Leander, G.; Vouk, M.

    1982-04-01

    Analogous to the equivalence between the SU(6) quadrupole-phonon model (TQM) and the interacting boson model (IBM), the equivalence is pointed out for odd systems between the SU(6) particle quadrupole-phonon coupling model (PTQM) and the interacting boson-fermion model (IBFM). PTQM is formulated starting from the Dyson representation for the odd system. Different aspects of the SU(3) limit of TQM and PTQM are studied; the quadrupole-phonon block structure of rotational bands in even and odd nuclei and analytic expressions based on the coherent state; signature effects generated in PTQM; electromagnetic properties and correction factors for PTQM; overlaps of the PTQM analogs of Nilsson states with Coriolis-coupled Nilsson states and the relation to the rotational model representation.

  9. Quadrupole ion trap studies of the structure and reactivity of transition metal ion pair complexes

    PubMed

    Vachet; Callahan

    2000-03-01

    Ion pairs are common species observed in the electrospray mass spectra of transition metal coordination complexes. To understand the nature of these ion pairs, a systematic study of the gas-phase chemistry of these species using ion-molecule reactions and collision-induced dissociation (CID) was carried out. Ion pair complexes of the type MLnX+ (where M is Mn(II), Fe(II), Co(II), Ni(II), Cu(II) or Zn(II), L is 1,10-phenanthroline, 2,2'-bipyridine, ethylenediamine, diethylenetriamine or 1,4,8,11-tetraazacyclotetradecane and X is Cl-, NO3-, acetylacetonate, ClO4-, acetate or SCN-) were studied. Ion-molecule reactions can distinguish whether the counterion in an ion pair is an inner- or outer-sphere ligand and can determine the coordination mode of the counterion. In addition, CID and ion-molecule reactions reveal some interesting chemistry of these complexes and unique coordination modes for some of the anions studied here were inferred from the ion-molecule reactions. For example, the thiocyanate ion is found to coordinate in a bidentate fashion in Zn(II) and Ni(II) complexes, contrasting behavior typically observed in solution. Also, certain Co(II) and Fe(II) ion pair complexes undergo oxidation reactions in which species such as dioxygen and nitric oxide from the counterions ClO4- and NO3- are transferred to the Co(II) and Fe(II) complexes, showing the inherent affinity of these metals for these molecules. These complexes were also studied by ion-molecule reactions and CID. Dioxygen in complexes formed by CID is demonstrated to be bidentate, suggesting the formation of a peroxo ligand with concurrent oxidation of the metal.

  10. Vibration study of the APS storage ring 0. 8 meter quadrupole magnet/magnet support assembly

    SciTech Connect

    Jendrzejczyk, J.A.; Wambsganss, M.W.; Smith, R.K.

    1991-06-01

    The objectives of this study are as follows: Determine the vibration characteristics (frequency, damping, and mode shapes) of the magnet on prototypic supports (the actual mounting system used to mount the magnet on the girder). Measure system response to ambient floor motion. Measure the effect of various modifications to determine if the magnet response can be modified to minimize unwanted response characteristics. Modifications investigated include support schemes, increasing system damping, and increasing mechanical rigidity. Measure system response to coolant flow. Determine vibrational characteristics of a large concrete block placed on a concrete floor, including response to ambient floor motions.

  11. Theoretical study of the electrostatic and steric effects on the spectroscopic characteristics of the metal-ligand unit of heme proteins. 2. C-O vibrational frequencies, 17O isotropic chemical shifts, and nuclear quadrupole coupling constants.

    PubMed

    Kushkuley, B; Stavrov, S S

    1997-02-01

    The quantum chemical calculations, vibronic theory of activation, and London-Pople approach are used to study the dependence of the C-O vibrational frequency, 17O isotropic chemical shift, and nuclear quadrupole coupling constant on the distortion of the porphyrin ring and geometry of the CO coordination, changes in the iron-carbon and iron-imidazole distances, magnitude of the iron displacement out of the porphyrin plane, and presence of the charged groups in the heme environment. It is shown that only the electrostatic interactions can cause the variation of all these parameters experimentally observed in different heme proteins, and the heme distortions could modulate this variation. The correlations between the theoretically calculated parameters are shown to be close to the experimentally observed ones. The study of the effect of the electric field of the distal histidine shows that the presence of the four C-O vibrational bands in the infrared absorption spectra of the carbon monoxide complexes of different myoglobins and hemoglobins can be caused by the different orientations of the different tautomeric forms of the distal histidine. The dependence of the 17O isotropic chemical shift and nuclear quadrupole coupling constant on pH and the distal histidine substitution can be also explained from the same point of view.

  12. Theoretical Study of the Electrostatic and Steric Effects on the Spectroscopic Characteristics of the Metal-Ligand Unit of Heme Proteins. 2. C-O Vibrational Frequencies, 17O Isotropic Chemical Shifts, and Nuclear Quadrupole Coupling Constants

    PubMed Central

    Kushkuley, Boris; Stavrov, Solomon S.

    1997-01-01

    The quantum chemical calculations, vibronic theory of activation, and London-Pople approach are used to study the dependence of the C-O vibrational frequency, 17O isotropic chemical shift, and nuclear quadrupole coupling constant on the distortion of the porphyrin ring and geometry of the CO coordination, changes in the iron-carbon and iron-imidazole distances, magnitude of the iron displacement out of the porphyrin plane, and presence of the charged groups in the heme environment. It is shown that only the electrostatic interactions can cause the variation of all these parameters experimentally observed in different heme proteins, and the heme distortions could modulate this variation. The correlations between the theoretically calculated parameters are shown to be close to the experimentally observed ones. The study of the effect of the electric field of the distal histidine shows that the presence of the four C-O vibrational bands in the infrared absorption spectra of the carbon monoxide complexes of different myoglobins and hemoglobins can be caused by the different orientations of the different tautomeric forms of the distal histidine. The dependence of the 17O isotropic chemical shift and nuclear quadrupole coupling constant on pH and the distal histidine substitution can be also explained from the same point of view. PMID:9017215

  13. Design study of a radio-frequency quadrupole for high-intensity beams

    NASA Astrophysics Data System (ADS)

    Bahng, Jungbae; Kim, Eun-San; Choi, Bong-Hyuk

    2017-07-01

    The Rare isotope Accelerator Of Newness (RAON) heavy-ion accelerator has been designed for the Rare Isotope Science Project (RISP) in Korea. The RAON will produce heavy-ion beams from 660-MeV-proton to 200-MeV/u-uranium with continuous wave (CW) power of 400 kW to support research in various scientific fields. Its system consists of an ECR ion source, LEBTs with 10 keV/u, CW RFQ accelerator with 81.25 MHz and 500 keV/u, a MEBT system, and a SC linac. In detail, the driver linac system consists of a Quarter Wave Resonator (QWR) section with 81.25 MHz and a Half Wave Resonator (HWR) section with 162.5 MHz, Linac-1, and a Spoke Cavity section with 325 MHz, Linac-2. These linacs have been designed to optimize the beam parameters to meet the required design goals. At the same time, a light-heavy ion accelerator with high-intensity beam, such as proton, deuteron, and helium beams, is required for experiments. In this paper, we present the design study of the high intensity RFQ for a deuteron beam with energies from 30 keV/u to 1.5 MeV/u and currents in the mA range. This system is composed of an Penning Ionization Gauge ion source, short LEBT with a RF deflector, and shared SC Linac. In order to increase acceleration efficiency in a short length with low cost, the 2nd harmonic of 162.5 MHz is applied as the operation frequency in the D+ RFQ design. The D+ RFQ is designed with 4.97 m, 1.52 bravery factor. Since it operates with 2nd harmonic frequency, the beam should be 50% of the duty factor while the cavity should be operated in CW mode, to protect the downstream linac system. We focus on avoiding emittance growth by the space-charge effect and optimizing the RFQ to achieve a high transmission and low emittance growth. Both the RFQ beam dynamics study and RFQ cavity design study for two and three dimensions will be discussed. Supported by Korea University Future Research Grant

  14. Hydrophilic interaction ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HILIC-UPLC-TQ-MS/MS) in multiple-reaction monitoring (MRM) for the determination of nucleobases and nucleosides in ginkgo seeds.

    PubMed

    Zhou, Guisheng; Pang, Hanqing; Tang, Yuping; Yao, Xin; Ding, Yunhe; Zhu, Shaoqing; Guo, Sheng; Qian, Dawei; Shen, Juan; Qian, Yefei; Su, Shulan; Zhang, Li; Jin, Chun; Qin, Yong; Duan, Jin-Ao

    2014-05-01

    In this study, a rapid, simple and sensitive analytical method was developed for the quantitative determination of 20 nucleosides and nucleobases in functional foods at trace levels using hydrophilic interaction ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HILIC-UPLC-TQ-MS/MS) in multiple-reaction monitoring (MRM) mode. Under optimised chromatographic conditions, good separation of 20 target compounds was achieved using a Waters Acquity UPLC BEH Amide column and gradient elution in 11min. The limits of detection (LODs) and quantification (LOQs) were between 0.02-42.54ng/mL and 0.05-98.18ng/mL for the 20 analytes, respectively. This is the first report about simultaneous analysis of nucleosides and nucleobases in functional foods using this method, which afforded good linearity, precision, repeatability and accuracy. The method developed was successfully applied to quantify target compounds in batches of ginkgo seeds. The method potentially could be used to determine polar and trace-level nucleosides and nucleobases in ginkgo seeds. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. ELECTRON TRAPPING IN WIGGLER AND QUADRUPOLE MAGNETS OF CESRTA

    SciTech Connect

    Wang, Lanfa; Huang, Xiaobiao; Pivi, Mauro; /SLAC

    2010-08-25

    The Cornell Electron Storage Ring (CESR) has been reconfigured as an ultra low emittance damping ring for use as a test accelerator (CesrTA) for International Linear Collider (ILC) damping ring R&D [1]. One of the primary goals of the CesrTA program is to investigate the interaction of the electron cloud with low emittance positron beam to explore methods to suppress the electron cloud, develop suitable advanced instrumentation required for these experimental studies and benchmark predictions by simulation codes. This paper reports the simulation of the electron-cloud formation in the wiggler and quadrupole magnets using the 3D code CLOUDLAND. We found that electrons can be trapped with long lifetime in a quadrupole magnet due to the mirror field trapping mechanism and photoelectrons produced in the wiggler zero field zone have long lifetime due to their complicated trajectory.

  16. Performance of the first short model 150 mm aperture Nb$_3$Sn Quadrupole MQXFS for the High- Luminosity LHC upgrade

    SciTech Connect

    Chlachidze, G.; et al.

    2016-08-30

    The US LHC Accelerator Research Program (LARP) and CERN combined their efforts in developing Nb3Sn magnets for the High-Luminosity LHC upgrade. The ultimate goal of this collaboration is to fabricate large aperture Nb3Sn quadrupoles for the LHC interaction regions (IR). These magnets will replace the present 70 mm aperture NbTi quadrupole triplets for expected increase of the LHC peak luminosity by a factor of 5. Over the past decade LARP successfully fabricated and tested short and long models of 90 mm and 120 mm aperture Nb3Sn quadrupoles. Recently the first short model of 150 mm diameter quadrupole MQXFS was built with coils fabricated both by the LARP and CERN. The magnet performance was tested at Fermilab’s vertical magnet test facility. This paper reports the test results, including the quench training at 1.9 K, ramp rate and temperature dependence studies.

  17. General form of the boson-fermion interaction in the interacting boson-fermion model-2

    NASA Astrophysics Data System (ADS)

    Matus, F. A.; Barea, J.

    2017-03-01

    The boson-fermion interaction in the interacting boson-fermion model-2 (IBFM-2) is derived in a systematic and general form from a quadrupole-quadrupole force using several nondegenerate levels. The boson-fermion quadrupole operator employed is obtained from the boson-fermion image of the one nucleon transfer operator which in turn can be calculated following two alternative schemes: the Otsuka-Arima-Iachello and generalized Holstein-Primakoff schemes. Four different terms (two quadrupole and two exchange) were obtained. Application of the new expressions to a single-j model is studied and analyzed.

  18. Double-photoionization of helium including quadrupole radiation effects

    SciTech Connect

    Colgan, James; Ludlow, J A; Lee, Teck - Ghee; Pindzola, M S; Robicheaux, F

    2009-01-01

    Non-perturbative time-dependent close-coupling calculations are carried out for the double photoionization of helium including both dipole and quadrupole radiation effects. At a photon energy of 800 eV, accessible at CUlTent synchrotron light sources, the quadrupole interaction contributes around 6% to the total integral double photoionization cross section. The pure quadrupole single energy differential cross section shows a local maxima at equal energy sharing, as opposed to the minimum found in the pure dipole single energy differential cross section. The sum of the pure dipole and pure quadrupole single energy differentials is insensitive to non-dipole effects at 800 eV. However, the triple differential cross section at equal energy sharing of the two ejected electrons shows strong non-dipole effects due to the quadrupole interaction that may be experimentally observable.

  19. Fundamental studies of ion injection and trapping of electrosprayed ions on a quadrupole ion trap mass spectrometer

    NASA Astrophysics Data System (ADS)

    Quarmby, Scott Thomas

    The quadrupole ion trap is a highly versatile and sensitive analytical mass spectrometer. Because of the advantages offered by the ion trap, there has been intense interest in coupling it to ionization techniques such as electrospray which form ions externally to the ion trap. In this work, experiments and computer simulations were employed to study the injection of electrosprayed ions into the ion trap of a Finnigan MAT LCQ LC/MS n mass spectrometer. The kinetic energy distribution of the ion beam was characterized and found to be relatively wide, a result of the high pressures from the atmospheric pressure source. One of the most important experimental parameters which affects ion injection efficiency is the RF voltage applied to the ring electrode. A theoretical model was fit to experimental data allowing the optimum RF voltage for trapping a given m/z ion to be predicted. Computer simulations of ion motion were performed to study the effect of various instrumental parameters on trapping efficiency. A commercially available ion optics program, SIMION v6.0, was chosen because it allowed the actual ion trap electrode geometry including endcap holes to be simulated. In contrast to previous computer simulations, SIMION provided the ability to start ions outside the ion trap and to simulate more accurately the injection of externally formed ions. The endcap holes were found to allow the RF field to penetrate out of the ion trap and affect ions as they approached the ion trap. From these simulations, a model for the process by which injected ions are trapped was developed. Using these computer simulations, techniques of improving trapping efficiency were investigated. Most previous techniques perturb ions which are already in the ion trap and therefore cannot be used to accumulate ions; the ability to accumulate ions is a necessity with ionization sources such as electrospray which form ions continuously. One such novel technique for improving trapping efficiency

  20. Ab initio correlated calculations of rare-gas dimer quadrupoles

    NASA Astrophysics Data System (ADS)

    Donchev, Alexander G.

    2007-10-01

    This paper reports ab initio calculations of rare gas ( RG=Kr , Ar, Ne, and He) dimer quadrupoles at the second order of Møller-Plesset perturbation theory (MP2). The study reveals the crucial role of the dispersion contribution to the RG2 quadrupole in the neighborhood of the equilibrium dimer separation. The magnitude of the dispersion quadrupole is found to be much larger than that predicted by the approximate model of Hunt. As a result, the total MP2 quadrupole moment is significantly smaller than was assumed in virtually all previous related studies. An analytical model for the distance dependence of the RG2 quadrupole is proposed. The model is based on the effective-electron approach of Jansen, but replaces the original Gaussian approximation to the electron density in an RG atom by an exponential one. The role of the nonadditive contribution in RG3 quadrupoles is discussed.

  1. Low-frequency nuclear quadrupole resonance with a dc SQUID

    SciTech Connect

    Chang, J.W.

    1991-07-01

    Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and application of a SQUID NQR technique which is capable of measuring intermediate strength quadrupolar interactions, in the range of a few hundred kilohertz to several megahertz. In this technique, a dc SQUID (Superconducting QUantum Interference Device) is used to monitor the longitudinal sample magnetization, as opposed to the transverse magnetization, as a rf field is swept in frequency. This allows the detection of low-frequency nuclear quadrupole resonances over a very wide frequency range with high sensitivity. The theory of this NQR technique is discussed and a description of the dc SQUID system is given. In the following chapters, the spectrometer is discussed along with its application to the study of samples containing half-odd-integer spin quadrupolar nuclei, in particular boron-11 and aluminum-27. The feasibility of applying this NQR technique in the study of samples containing integer spin nuclei is discussed in the last chapter. 140 refs., 46 figs., 6 tabs.

  2. Low-frequency nuclear quadrupole resonance with a dc SQUID

    SciTech Connect

    Chang, J.W.

    1991-07-01

    Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and application of a SQUID NQR technique which is capable of measuring intermediate strength quadrupolar interactions, in the range of a few hundred kilohertz to several megahertz. In this technique, a dc SQUID (Superconducting QUantum Interference Device) is used to monitor the longitudinal sample magnetization, as opposed to the transverse magnetization, as a rf field is swept in frequency. This allows the detection of low-frequency nuclear quadrupole resonances over a very wide frequency range with high sensitivity. The theory of this NQR technique is discussed and a description of the dc SQUID system is given. In the following chapters, the spectrometer is discussed along with its application to the study of samples containing half-odd-integer spin quadrupolar nuclei, in particular boron-11 and aluminum-27. The feasibility of applying this NQR technique in the study of samples containing integer spin nuclei is discussed in the last chapter. 140 refs., 46 figs., 6 tabs.

  3. SUPERCONDUCTING QUADRUPOLE ARRAYS FOR MULTIPLE BEAM TRANSPORT

    SciTech Connect

    Rainer Meinke Carl Goodzeit Penny Ball Roger Bangerter

    2003-10-01

    The goal of this research was to develop concepts for affordable, fully functional arrays of superconducting quadrupoles for multi-beam transport and focusing in heavy ion fusion (HIF)accelerators. Previous studies by the Virtual National Laboratory (VNL) collaboration have shown that the multi-beam transport system (consisting of alternating gradient quadrupole magnets, a beam vacuum system, and the beam monitor and control system) will likely be one of the most expensive and critical parts of such an accelerator. This statement is true for near-term fusion research accelerators as well as accelerators for the ultimate goal of power production via inertial fusion. For this reason, research on superconducting quadrupole arrays is both timely and important for the inertial fusion energy (IFE) research program. This research will also benefit near-term heavy ion fusion facilities such as the Integrated Research Experiment (IRE)and/or the Integrated Beam Experiment (IBX). We considered a 2-prong approach that addresses the needs of both the nearer and longer term requirements of the inertial fusion program. First, we studied the flat coil quadrupole design that was developed by LLNL; this magnet is 150 mm long with a 50 mm aperture and thus is suitable for near term experiments that require magnets of a small length to aperture ratio. Secondly, we studied the novel double-helix quadrupole (DHQ) design in a small (3 x 3) array configuration; this design can provide an important step to the longer term solution of low-cost, easy to manufacture array constructions. Our Phase I studies were performed using the AMPERES magnetostatic analysis software. Consideration of these results led to plans for future magnet R&D construction projects. The first objective of Phase I was to develop the concept of a superconducting focusing array that meets the specific requirements of a heavy ion fusion accelerator. Detailed parameter studies for such quadrupole arrays were performed

  4. Magnetic mirror structure for testing shell-type quadrupole coils

    SciTech Connect

    Andreev, N.; Barzi, E.; Bossert, R.; Chlachidze, G.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.; Tartaglia, N.; Turrioni, D.; /Fermilab

    2009-10-01

    This paper presents magnetic and mechanical designs and analyses of the quadrupole mirror structure to test single shell-type quadrupole coils. Several quadrupole coils made of different Nb{sub 3}Sn strands, cable insulation and pole materials were tested using this structure at 4.5 and 1.9 K. The coils were instrumented with voltage taps, spot heaters, temperature sensors and strain gauges to study their mechanical and thermal properties and quench performance. The results of the quadrupole mirror model assembly and test are reported and discussed.

  5. Variable Permanent Magnet Quadrupole

    SciTech Connect

    Mihara, T.; Iwashita, Y.; Kumada, M.; Spencer, C.M.; /SLAC

    2007-05-23

    A permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens in a linear collider. An over 120 T/m strong variable permanent magnet quadrupole is achieved by the introduction of saturated iron and a 'double ring structure'. A fabricated PMQ achieved 24 T integrated gradient with 20 mm bore diameter, 100 mm magnet diameter and 20 cm pole length. The strength of the PMQ is adjustable in 1.4 T steps, due to its 'double ring structure': the PMQ is split into two nested rings; the outer ring is sliced along the beam line into four parts and is rotated to change the strength. This paper describes the variable PMQ from fabrication to recent adjustments.

  6. Application of nuclear quadrupole resonance to the study of clathrates. sup 35 Cl NQR and crystallography of clathrated CCl sub 4

    SciTech Connect

    Pang, Li; Lucken, E.A.C.; Bernardinelli, G. )

    1990-11-21

    The {sup 35}Cl nuclear quadrupole resonance (NQR) spectra of CCl{sub 4} in more than 20 clathrates have been measured in the range 4-200 K. The crystal structures of CCl{sub 4}/Dianin's compound (1), CCl{sub 4}/Fe(AcAc){sub 3} (3), CCl{sub 4}/Ni(SCN){sub 2}(3-MePy){sub 4} (4), and CCl{sub 4}/Ni(exan){sub 2}(4,4{prime}-dm-2,2{prime}-bpy) (19) clathrates are also reported. Site symmetry and site multiplicity of the guest molecule in clathrates were determined by NQR spectroscopy and by x-ray crystallography. The degree of host-guest interaction was estimated from the NQR frequency shifts. The libration frequencies of the guest molecules in trigonal cavities were determined from NQR frequencies by Bayer-Kushida theory analysis.

  7. Cephradine antacids interaction studies.

    PubMed

    Arayne, M Saeed; Sultana, Najma; Afzal, M

    2007-07-01

    The present work comprises of interaction studies of cephradine with antacids. Cephradine is included among the first generation cephalosporin, which is active against a wide range of Gram positive and Gram-negative bacteria including penicillinase-producing staphylococci. Since the presence of complexing ligand may affect the bioavailability of a drug in blood or tissues, therefore, in order to study the probable interaction of cephradine with antacids all the reaction conditions were simulated to natural environments. Antacids are commonly used in patients complaining of GI irritations. The behavior of cephradine in presence of seven antacids i.e., simethicone, magaldrate, magnesium carbonate, magnesium hydroxide, magnesium trisilicate, sodium bicarbonate and aluminium hydroxide was studied by using standard dissolution apparatus. Cephradine was monitored both by UV and by high performance liquid chromatography. The results revealed that antacids containing polyvalent cations retarded the in vitro availability of cephradine. Moreover, these studies indicated that cephradine was strongly adsorbed on antacids; magnesium trisilicate and simeco tablets (powdered) exhibited relatively higher adsorption capacities.

  8. Study of Row Phase Dependent Skew Quadrupole Fields in Apple-II Type EPUs at the ALS

    SciTech Connect

    Steier, C.; Marks, S.; Prestemon, Soren; Robin, David; Schlueter, Ross; Wolski, Andrzej

    2004-05-07

    Since about 5 years, Apple-II type Elliptically Polarizing Undulators (EPU) have been used very successfully at the ALS to generate high brightness photon beams with arbitrary polarization. However, both EPUs installed so far cause significant changes of the vertical beamsize, especially when the row phase is changed to change the polarization of the photons emitted. Detailed measurements indicate this is caused by a row phase dependent skew quadrupole term in the EPUs. Magnetic measurements revealed the same effect for the third EPU to be installed later this year. All measurements to identify and quantify the effect with beam will be presented, as well as some results of magnetic bench measurements and numeric field simulations.

  9. Extended nuclear quadrupole resonance study of the heavy-fermion superconductor PuCoGa5

    SciTech Connect

    Koutroulakis, Georgios; Yasuoka, Hiroshi; Tobash, Paul H.; Mitchell, Jeremy Neil; Bauer, Eric Dietzgen; Thompson, Joe David

    2016-10-10

    PuCoGa5 has emerged as a prototypical heavy-fermion superconductor, with its transition temperature (Tc ≃ 18.5 K) being the highest amongst such materials. Nonetheless, a clear description as to what drives the superconducting pairing is still lacking, rendered complicated by the notoriously intricate nature of plutonium's 5f valence electrons. Here, we present a detailed 69,71Ga nuclear quadrupole resonance (NQR) study of PuCoGa5, concentrating on the system's normal state properties near to Tc and aiming to detect distinct signatures of possible pairing mechanisms. In particular, the quadrupole frequency and spin-lattice relaxation rate were measured for the two crystallographically inequivalent Ga sites and for both Ga isotopes, in the temperature range 1.6–300 K. No evidence of significant charge fluctuations is found from the NQR observables. On the contrary, the low-energy dynamics is dominated by anisotropic spin fluctuations with strong, nearly critical, in-plane character, which are effectively identical to the case of the sister compound PuCoIn5. Lastly, these findings are discussed within the context of different theoretical proposals for the unconventional pairing mechanism in heavy-fermion superconductors.

  10. Extended nuclear quadrupole resonance study of the heavy-fermion superconductor PuCoGa5

    SciTech Connect

    Koutroulakis, Georgios; Yasuoka, Hiroshi; Tobash, Paul H.; Mitchell, Jeremy Neil; Bauer, Eric Dietzgen; Thompson, Joe David

    2016-10-10

    PuCoGa5 has emerged as a prototypical heavy-fermion superconductor, with its transition temperature (Tc ≃ 18.5 K) being the highest amongst such materials. Nonetheless, a clear description as to what drives the superconducting pairing is still lacking, rendered complicated by the notoriously intricate nature of plutonium's 5f valence electrons. Here, we present a detailed 69,71Ga nuclear quadrupole resonance (NQR) study of PuCoGa5, concentrating on the system's normal state properties near to Tc and aiming to detect distinct signatures of possible pairing mechanisms. In particular, the quadrupole frequency and spin-lattice relaxation rate were measured for the two crystallographically inequivalent Ga sites and for both Ga isotopes, in the temperature range 1.6–300 K. No evidence of significant charge fluctuations is found from the NQR observables. On the contrary, the low-energy dynamics is dominated by anisotropic spin fluctuations with strong, nearly critical, in-plane character, which are effectively identical to the case of the sister compound PuCoIn5. Lastly, these findings are discussed within the context of different theoretical proposals for the unconventional pairing mechanism in heavy-fermion superconductors.

  11. Critical Density Interaction Studies

    SciTech Connect

    Young, P; Baldis, H A; Cheung, P; Rozmus, W; Kruer, W; Wilks, S; Crowley, S; Mori, W; Hansen, C

    2001-02-14

    Experiments have been performed to study the propagation of intense laser pulses to high plasma densities. The issue of self-focusing and filamentation of the laser pulse as well as developing predictive capability of absorption processes and x-ray conversion efficiencies is important for numerous programs at the Laboratory, particularly Laser Program (Fast Ignitor and direct-drive ICF) and D&NT (radiography, high energy backlighters and laser cutting). Processes such as resonance absorption, profile modification, linear mode conversion, filamentation and stimulated Brillouin scattering can occur near the critical density and can have important effects on the coupling of laser light to solid targets. A combination of experiments have been used to study the propagation of laser light to high plasma densities and the interaction physics of intense laser pulses with solid targets. Nonparaxial fluid codes to study nonstationary behavior of filamentation and stimulated Brillouin scattering at high densities have also been developed as part of this project.

  12. MQXFS1 Quadrupole Design Report

    SciTech Connect

    Ambrosio, Giorgio

    2016-04-14

    This report presents the reference design of MQXFS1, the first 1.5 m prototype of the low-beta quadrupoles (MQXF) for the LHC High Luminosity Upgrade. The MQXF quadrupoles have 150 mm aperture, coil peak field of about 12 T, and use $Nb_{3}Sn$ conductor. The design is based on the LARP HQ quadrupoles, which had 120 mm aperture. MQXFS1 has 1st generation cable cross-section and magnetic design.

  13. Using nitrogen-14 nuclear quadrupole resonance and electric field gradient information for the study of radiation effects

    SciTech Connect

    Iselin, L.H.

    1995-12-01

    Nitrogen-14 nuclear quadrupole resonance (NQR) was used in an attempt to detect the effects of ionizing radiation on organic material. Previously reported resonances for urea were detected at 2,913.32 {+-} 0.01 kHz and 2,347.88 {+-} 0.08 kHz with associated T{sub 2}* values 780 {+-} 20 {micro}s and 523 {+-} 24 {micro}s, respectively. The previously unreported {nu}{sub {minus}} line for urea-d{sup 4} was detected at 2,381 {+-} 0.04 Khz and used to determine accurately for the first time the values for the nuclear quadrupole coupling constant {chi} (3,548.74 {+-} 0.03 kHz) and the asymmetry parameter {eta} (0.31571 {+-} 0.00007) for urea-d{sup 4}. The inverse linewidth parameter T{sub 2}* for {nu}{sub +} was measured at 928 {+-} 23 {micro}s and for {nu}{sub {minus}} at 721 {+-} 12 {micro}s. Townes and Dailey analysis was performed and urea-d{sup 4} exhibits a 0.004 increase in lone pair electronic density and a slight decrease in N-H bond electronic density, as compared to urea, probably due to the mass difference. A relationship is proposed, referred to as NQR linewidth analysis, between the dynamic spin relaxation times T{sub 2} and T{sub 2}* and the widths of the distributions of the NQR parameters. Linewidth analysis is presented as a tool for possible use in future NQR work in all area, not just radiation effects. This relationship is tested using sodium nitrite T{sub 2} and T{sub 2}* values for {nu}{sub {minus}} and {nu}{sub {minus}} as a function of temperature.

  14. Rescuing the nonjet (NJ) azimuth quadrupole from the flow narrative

    NASA Astrophysics Data System (ADS)

    Trainor, Thomas A.

    2017-04-01

    According to the flow narrative commonly applied to high-energy nuclear collisions a cylindrical-quadrupole component of 1D azimuth angular correlations is conventionally denoted by quantity υ2 and interpreted to represent elliptic flow. Jet angular correlations may also contribute to υ2 data "nonflow" depending on the method used to calculate υ2, but 2D graphical methods are available to insure accurate separation. The nonjet (NJ) quadrupole has various properties inconsistent with a flow interpretation, including the observation that NJ quadrupole centrality variation in A-A collisions has no relation to strongly-varying jet modication ("jet quenching") in those collisions commonly attributed to jet interaction with a flowing dense medium. In this presentation I describe isolation of quadrupole spectra from pt-differential υ2(pt) data from the RHIC and LHC. I demonstrate that quadrupole spectra have characteristics very different from the single-particle spectra for most hadrons, that quadrupole spectra indicate a common boosted hadron source for a small minority of hadrons that "carry" the NJ quadrupole structure, that the narrow source-boost distribution is characteristic of an expanding thin cylindrical shell (strongly contradicting hydro descriptions), and that in the boost frame a single universal quadrupole spectrum (Lévy distribution) on transverse mass mt accurately describes data for several hadron species scaled according to their statistical-model abundances. The quadrupole spectrum shape changes very little from RHIC to LHC energies. Taken in combination those characteristics strongly suggest a unique nonflow (and nonjet) QCD mechanism for the NJ quadrupole conventionally represented by υ2.

  15. Commissioning a Vibrating Wire System for Quadrupole Fiducialization

    SciTech Connect

    Levashov, Michael Y

    2010-12-03

    Quadrupoles will be placed between the undulator segments in LCLS to keep the electron beam focused as it passes through. The quadrupoles will be assembled with their respective undulator segments prior to being placed into the tunnel. Beam alignment will be used to center the quadrupoles, along with the corresponding undulators, on the beam. If there is any displacement between the undulator and the quadrupole axes in the assemblies, the beam will deviate from the undulator axis. If it deviates by more than 80{micro}m in vertical or 140{micro}m in horizontal directions, the undulator will not perform as required by LCLS. This error is divided between three sources: undulator axis fiducialization, quadrupole magnetic axis fiducialization, and assembly of the two parts. In particular, it was calculated that the quadrupole needs to be fiducialized to within 25{micro}m in both vertical and horizontal directions. A previous study suggested using a vibrating wire system for finding the magnetic axis of the quadrupoles. The study showed that the method has high sensitivity (up to 1{micro}m) and laid out guidelines for constructing such a system. There are 3 steps in fiducializing the quadrupole with the vibrating wire system. They are positioning the wire at the magnet center (step 1), finding the wire with position detectors (step 2), and finding the quadrupole tooling ball positions relative to the position detector tooling balls (step 3). A previous study investigated the error associated with each step by using a permanent quadrupole magnet on an optical mover system. The study reported an error of 11{micro}m for step 1 and a repeatability of 4{micro}m for step 2. However, the set up used a FARO arm to measure tooling balls and didn't allow to accurately check step 2 for errors; an uncertainty of 100{micro}m was reported. Therefore, even though the repeatability was good, there was no way to check that the error in step 2 was small. Following the recommendations of

  16. Arc electrode interaction study

    NASA Technical Reports Server (NTRS)

    Zhou, X.; Berns, D.; Heberlein, J.

    1994-01-01

    The project consisted of two parts: (1) the cathode interaction studies which were a continuation of previous work and had the objective of increasing our understanding of the microscopic phenomena controlling cathode erosion in arc jet thrusters, and (2) the studies of the anode attachment in arc jet thrusters. The cathode interaction studies consisted of (1) a continuation of some modeling work in which the previously derived model for the cathode heating was applied to some specific gases and electrode materials, and (2) experimental work in which various diagnostics was applied to the cathode. The specific diagnostics used were observation of the cathode tip during arcing using a Laser Strobe Video system in conjunction with a tele-microscope, a monochromator with an optical multichannel analyzer for the determination of the cathode temperature distribution, and various ex situ materials analysis methods. The emphasis of our effort was shifted to the cathode materials analysis because a parallel project was in place during the second half of 1993 with a visiting scientist pursuing arc electrode materials studies. As a consequence, the diagnostic investigations of the arc in front of the cathode had to be postponed to the first half of 1994, and we are presently preparing these measurements. The results of last year's study showed some unexpected effects influencing the cathode erosion behavior, such as increased erosion away from the cathode tip, and our understanding of these effects should improve our ability to control cathode erosion. The arc jet anode attachment studies concentrated on diagnostics of the instabilities in subsonic anode attachment arc jet thrusters, and were supplemental measurements to work which was performed by one of the authors who spent the summer as an intern at NASA Lewis Research Center. A summary of the results obtained during the internship are included because they formed an integral part of the study. Two tasks for 1994, the

  17. Superconducting quadrupoles for the SLC final focus

    SciTech Connect

    Erickson, R.; Fieguth, T.; Murray, J.J.

    1987-01-01

    The final focus system of the SLC will be upgraded by replacing the final quadrupoles with higher gradient superconducting magnets positioned closer to the interaction point. The parameters of the new system have been chosen to be compatible with the experimental detectors with a minimum of changes to other final focus components. These parameter choices are discussed along with the expected improvement in SLC performance.

  18. Molecular near-field antenna effect in resonance hyper-Raman scattering: intermolecular vibronic intensity borrowing of solvent from solute through dipole-dipole and dipole-quadrupole interactions.

    PubMed

    Shimada, Rintaro; Hamaguchi, Hiro-o

    2014-05-28

    We quantitatively interpret the recently discovered intriguing phenomenon related to resonance Hyper-Raman (HR) scattering. In resonance HR spectra of all-trans-β-carotene (β-carotene) in solution, vibrations of proximate solvent molecules are observed concomitantly with the solute β-carotene HR bands. It has been shown that these solvent bands are subject to marked intensity enhancements by more than 5 orders of magnitude under the presence of β-carotene. We have called this phenomenon the molecular-near field effect. Resonance HR spectra of β-carotene in benzene, deuterated benzene, cyclohexane, and deuterated cyclohexane have been measured precisely for a quantitative analysis of this effect. The assignments of the observed peaks are made by referring to the infrared, Raman, and HR spectra of neat solvents. It has been revealed that infrared active and some Raman active vibrations are active in the HR molecular near-field effect. The observed spectra in the form of difference spectra (between benzene/deuterated benzene and cyclohexane/deuterated cyclohexane) are quantitatively analyzed on the basis of the extended vibronic theory of resonance HR scattering. The theory incorporates the coupling of excited electronic states of β-carotene with the vibrations of a proximate solvent molecule through solute-solvent dipole-dipole and dipole-quadrupole interactions. It is shown that the infrared active modes arise from the dipole-dipole interaction, whereas Raman active modes from the dipole-quadrupole interaction. It is also shown that vibrations that give strongly polarized Raman bands are weak in the HR molecular near-field effect. The observed solvent HR spectra are simulated with the help of quantum chemical calculations for various orientations and distances of a solvent molecule with respect to the solute. The observed spectra are best simulated with random orientations of the solvent molecule at an intermolecular distance of 10 Å.

  19. Molecular near-field antenna effect in resonance hyper-Raman scattering: Intermolecular vibronic intensity borrowing of solvent from solute through dipole-dipole and dipole-quadrupole interactions

    SciTech Connect

    Shimada, Rintaro; Hamaguchi, Hiro-o

    2014-05-28

    We quantitatively interpret the recently discovered intriguing phenomenon related to resonance Hyper-Raman (HR) scattering. In resonance HR spectra of all-trans-β-carotene (β-carotene) in solution, vibrations of proximate solvent molecules are observed concomitantly with the solute β-carotene HR bands. It has been shown that these solvent bands are subject to marked intensity enhancements by more than 5 orders of magnitude under the presence of β-carotene. We have called this phenomenon the molecular-near field effect. Resonance HR spectra of β-carotene in benzene, deuterated benzene, cyclohexane, and deuterated cyclohexane have been measured precisely for a quantitative analysis of this effect. The assignments of the observed peaks are made by referring to the infrared, Raman, and HR spectra of neat solvents. It has been revealed that infrared active and some Raman active vibrations are active in the HR molecular near-field effect. The observed spectra in the form of difference spectra (between benzene/deuterated benzene and cyclohexane/deuterated cyclohexane) are quantitatively analyzed on the basis of the extended vibronic theory of resonance HR scattering. The theory incorporates the coupling of excited electronic states of β-carotene with the vibrations of a proximate solvent molecule through solute–solvent dipole–dipole and dipole–quadrupole interactions. It is shown that the infrared active modes arise from the dipole–dipole interaction, whereas Raman active modes from the dipole–quadrupole interaction. It is also shown that vibrations that give strongly polarized Raman bands are weak in the HR molecular near-field effect. The observed solvent HR spectra are simulated with the help of quantum chemical calculations for various orientations and distances of a solvent molecule with respect to the solute. The observed spectra are best simulated with random orientations of the solvent molecule at an intermolecular distance of 10 Å.

  20. Molecular near-field antenna effect in resonance hyper-Raman scattering: Intermolecular vibronic intensity borrowing of solvent from solute through dipole-dipole and dipole-quadrupole interactions

    NASA Astrophysics Data System (ADS)

    Shimada, Rintaro; Hamaguchi, Hiro-o.

    2014-05-01

    We quantitatively interpret the recently discovered intriguing phenomenon related to resonance Hyper-Raman (HR) scattering. In resonance HR spectra of all-trans-β-carotene (β-carotene) in solution, vibrations of proximate solvent molecules are observed concomitantly with the solute β-carotene HR bands. It has been shown that these solvent bands are subject to marked intensity enhancements by more than 5 orders of magnitude under the presence of β-carotene. We have called this phenomenon the molecular-near field effect. Resonance HR spectra of β-carotene in benzene, deuterated benzene, cyclohexane, and deuterated cyclohexane have been measured precisely for a quantitative analysis of this effect. The assignments of the observed peaks are made by referring to the infrared, Raman, and HR spectra of neat solvents. It has been revealed that infrared active and some Raman active vibrations are active in the HR molecular near-field effect. The observed spectra in the form of difference spectra (between benzene/deuterated benzene and cyclohexane/deuterated cyclohexane) are quantitatively analyzed on the basis of the extended vibronic theory of resonance HR scattering. The theory incorporates the coupling of excited electronic states of β-carotene with the vibrations of a proximate solvent molecule through solute-solvent dipole-dipole and dipole-quadrupole interactions. It is shown that the infrared active modes arise from the dipole-dipole interaction, whereas Raman active modes from the dipole-quadrupole interaction. It is also shown that vibrations that give strongly polarized Raman bands are weak in the HR molecular near-field effect. The observed solvent HR spectra are simulated with the help of quantum chemical calculations for various orientations and distances of a solvent molecule with respect to the solute. The observed spectra are best simulated with random orientations of the solvent molecule at an intermolecular distance of 10 Å.

  1. First-principles study of boron oxygen hole centers in crystals: Electronic structures and nuclear hyperfine and quadrupole parameters

    SciTech Connect

    Li Zucheng; Pan Yuanming

    2011-09-15

    The electronic structures, nuclear hyperfine coupling constants, and nuclear quadrupole parameters of fundamental boron oxygen hole centers (BOHCs) in zircon (ZrSiO{sub 4}, I4{sub 1}/amd) and calcite (CaCO{sub 3}, R3c) have been investigated using ab initio Hartree-Fock (HF) and various density functional theory (DFT) methods based on the supercell models with all-electron localized basis sets. Both exact HF exchange and appropriate correlation functionals are important in describing the BOHCs, and the parameter-free hybrid method based on Perdew, Burke, and Ernzerhof density functionals (PBE0) turns out to be the best DFT method in reproducing the electron paramagnetic resonance (EPR) data. Our results reveal three distinct types of simple-spin (S = 1/2) [BO{sub 3}]{sup 2-} centers in calcite: (i) the classic [BO{sub 3}]{sup 2-} radical with the D{sub 3h} symmetry and the unpaired spin equally distributed on the three oxygen atoms (i.e. the O{sub 3}{sup 5-} type); (ii) the previously reported [BO{sub 2}]{sup 0} center with the unpaired spin equally distributed on two of the three oxygen atoms (O{sub 2}{sup 3-}); and (iii) a new variety with {approx}90% of its unpaired spin localized on one (O{sup -}) of the three oxygen atoms with a long B-O bond (1.44 A). Calculations confirm the unusual [BO{sub 4}]{sup 0} center in zircon and show it to arise from a highly distorted configuration with 90% of the unpaired spin on one oxygen atom that has a considerably longer B-O bond (1.68 A) than its three counterparts (1.45 A). The calculated magnitudes and directions of {sup 11}B and {sup 17}O hyperfine coupling constants and nuclear quadrupole constants for the [BO{sub 4}]{sup 0} center in zircon are in excellent agreement with the 15 K EPR experimental data. These BOHCs are all characterized by a small negative spin density on the central B atom arising from spin polarization. Our calculations also demonstrate that the spin densities on BOHCs are affected substantially by

  2. Study of the electronics architecture for the mechanical stabilisation of the quadrupoles of the CLIC linear accelerator

    NASA Astrophysics Data System (ADS)

    Artoos, K.; Collette, C.; Fernandez Carmona, P.; Guinchard, M.; Hauviller, C.; Janssens, S.; Kuzmin, A.; Slaathaug, A.

    2010-11-01

    To reach a sufficient luminosity, the transverse beam sizes and emittances in future linear particle accelerators should be reduced to the nanometer level. Mechanical stabilisation of the quadrupole magnets is of the utmost importance for this. The piezo actuators used for this purpose can also be used to make fast incremental orientation adjustments with a nanometer resolution. The main requirements for the CLIC stabilisation electronics is a robust, low noise, low delay, high accuracy and resolution, low band and radiation resistant feedback control loop. Due to the high number of controllers (about 4000) a cost optimization should also be made. Different architectures are evaluated for a magnet stabilisation prototype, including the sensors type and configuration, partition between software and hardware for control algorithms, and optimization of the ADC/DAC converters. The controllers will be distributed along the 50 km long accelerator and a communication bus should allow external control. Furthermore, one might allow for an adaptive method to increase the S/N ratio of vibration measurements by combining seismometer measurements of adjacent magnets. Finally a list of open topics, the current limitations and the plans to overcome them will be presented.

  3. Evolution of an Unconventional Superconducting State inside the Antiferromagnetic Phase of CeNiGe3 under Pressure: A 73Ge-Nuclear-Quadrupole-Resonance Study

    NASA Astrophysics Data System (ADS)

    Harada, Atsushi; Mukuda, Hidekazu; Kitaoka, Yoshio; Thamizhavel, Arumugam; Okuda, Yusuke; Settai, Rikio; Ōnuki, Yoshichika; Itoh, Kouhei M.; Haller, Eugene E.; Harima, Hisatomo

    2008-10-01

    We report a 73Ge nuclear-quadrupole-resonance (NQR) study on novel evolution of unconventional superconductivity in antiferromagnetic (AFM) CeNiGe3. The measurements of the 73Ge-NQR spectrum and the nuclear spin-lattice relaxation rate (1/T1) have revealed that the unconventional superconductivity evolves inside a commensurate AFM phase around the pressure (P) where Néel temperature TN exhibits its maximum at 8.5 K. The superconducting transition temperature TSC has been found to be enhanced with increasing TN, before reaching the quantum critical point at which the AFM order collapses. Above TSC, the AFM structure transits from an incommensurate spin-density-wave order to a commensurate AFM order at T˜ 2 K, accompanied by a longitudinal spin-density fluctuation. With regard to heavy-fermion compounds, these novel phenomena have hitherto never been reported in the P-T phase diagram.

  4. Relativistic unitary coupled-cluster study of the electric quadrupole moment and magnetic dipole hyperfine constants of {sup 199}Hg{sup +}

    SciTech Connect

    Sur, Chiranjib; Chaudhuri, Rajat K.

    2007-09-15

    Searching for an accurate optical clock which can serve as a better time standard than the present-day atomic clock is highly demanding from several areas of science and technology. Several attempts have been made to build more accurate clocks with different ion species. In this paper, we discuss the electric quadrupole and hyperfine shifts in the 5d{sup 9}6s{sup 2} {sup 2}D{sub 5/2}(F=0,m{sub F}=0){r_reversible}5d{sup 10}6s {sup 2}S{sub 1/2}(F=2,m{sub F}=0) clock transition in {sup 199}Hg{sup +}, one of the most promising candidates for next-generation optical clocks. We have applied Fock-space unitary coupled-cluster theory to study the electric quadrupole moment of the 5d{sup 9}6s{sup 2} {sup 2}D{sub 5/2} state and magnetic dipole hyperfine constants of 5d{sup 9}6s{sup 2} {sup 2}D{sub 3/2,5/2} and 5d{sup 10}6s{sup 1} {sup 2}S{sub 1/2} states, respectively, of {sup 199}Hg{sup +}. We have also compared our results with available data. To the best of our knowledge, this is the first time a variant of coupled-cluster theories has been applied to study these kinds of properties of Hg{sup +} and is the most accurate estimate of these quantities to date.

  5. Studies on Strong Interactions

    NASA Astrophysics Data System (ADS)

    Coriano, Claudio

    Five studies, four in Quantum field theory and one in fermionic molecular dynamics are presented. In the first study, introduced in chapter one and developed in chapter two of this dissertation, we formulate an extension of QCD sum rules to Compton scattering of the pion at intermediate energy. The chapter is based on the research paper Fixed angle pion Compton scattering and QCD sum rules by Prof. George Sterman and the author, which has been submitted for publication as a regular article. In chapter 3 we discuss the relation between traditional bosonic exchange models of nuclear strong interaction and soliton models, in the particular case of the sine-Gordon model. The chapter is based on the research paper "Scattering in soliton models and bosonic exchange descriptions", by R. R. Parwani, H. Yamagishi, I. Zahed and the author, and is published in Phys. Rev. D 45 (1992), 2542. A preprint of this paper (Preprint 1) has been included as an Appendix to the Chapter. In Chapter 4 we discuss aspects of the propagation of quantized fields in classical backgrounds, using the light-cone expansion of the propagator. The chapter is based on the research papers "Electrodynamics in the presence of an axion", published by the author in Modern Physics Letters A 7 (1992), 1253, and on the paper "Singularity of Green's function and the effective action in massive Yang Mills theories, by Prof. H. Yamagishi and the author. This last paper is published in Physical Review D 41 (1990), 3226 and its reprint appears in the final part of the Chapter (Reprint 1). In chapter 5, entitled "On the time dependent Rayleigh-Ritz equations", we discuss aspects of the variational approach to fermionic molecular dynamics. This investigation by R. Parwani, H. Yamagishi and the author has been published in Nucl. Physics A 522 (1991), 591. A preprint of this research paper has been inserted in the final part of the Chapter (Preprint 2).

  6. Static quadrupole moment of the five-quasiparticle k = 35/2 isomer in (179)w studied with the level-mixing spectroscopy method.

    PubMed

    Balabanski, D L; Vyvey, K; Neyens, G; Coulier, N; Coussement, R; Georgiev, G; Lèpine-Szily, A; Ternier, S; Teughels, S; Mineva, M; Walker, P M; Blaha, P; Almehed, D; Frauendorf, S

    2001-01-22

    The spectroscopic quadrupole moment of the high-spin, high- K five-quasiparticle isomer (K(pi) = 35/2(-), T(1/2) = 750(80) ns, E(i) = 3349 keV) in (179)W has been determined using the level mixing spectroscopy method. A value Q(s) = 4.00(+0.83-1.06)e b was derived, which corresponds to an intrinsic quadrupole moment Q0 = 4.73(+0.98-1.25)e b and to a quadrupole deformation beta(2) = 0.185(+0.038-0.049). These values differ significantly from the deduced ground-state quadrupole moments and are in disagreement with the current theoretical predictions in this mass region.

  7. Quadrupole-enhanced Raman scattering.

    PubMed

    Hastings, Simon P; Swanglap, Pattanawit; Qian, Zhaoxia; Fang, Ying; Park, So-Jung; Link, Stephan; Engheta, Nader; Fakhraai, Zahra

    2014-09-23

    Dark, nonradiating plasmonic modes are important in the Raman enhancement efficiency of nanostructures. However, it is challenging to engineer such hotspots with predictable enhancement efficiency through synthesis routes. Here, we demonstrate that spiky nanoshells have designable quadrupole resonances that efficiently enhance Raman scattering with unprecedented reproducibility on the single particle level. The efficiency and reproducibility of Quadrupole Enhanced Raman Scattering (QERS) is due to their heterogeneous structure, which broadens the quadrupole resonance both spatially and spectrally. This spectral breadth allows for simultaneous enhancement of both the excitation and Stokes frequencies. The quadrupole resonance can be tuned by simple modifications of the nanoshell geometry. The combination of tunability, high efficiency, and reproducibility makes these nanoshells an excellent candidate for applications such as biosensing, nanoantennaes, and photovoltaics.

  8. Plasma-beam traps and radiofrequency quadrupole beam coolers.

    PubMed

    Maggiore, M; Cavenago, M; Comunian, M; Chirulotto, F; Galatà, A; De Lazzari, M; Porcellato, A M; Roncolato, C; Stark, S; Caruso, A; Longhitano, A; Cavaliere, F; Maero, G; Paroli, B; Pozzoli, R; Romé, M

    2014-02-01

    Two linear trap devices for particle beam manipulation (including emittance reduction, cooling, control of instabilities, dust dynamics, and non-neutral plasmas) are here presented, namely, a radiofrequency quadrupole (RFQ) beam cooler and a compact Penning trap with a dust injector. Both beam dynamics studies by means of dedicated codes including the interaction of the ions with a buffer gas (up to 3 Pa pressure), and the electromagnetic design of the RFQ beam cooler are reported. The compact multipurpose Penning trap is aimed to the study of multispecies charged particle samples, primarily electron beams interacting with a background gas and/or a micrometric dust contaminant. Using a 0.9 T solenoid and an electrode stack where both static and RF electric fields can be applied, both beam transport and confinement operations will be available. The design of the apparatus is presented.

  9. Plasma-beam traps and radiofrequency quadrupole beam coolers

    SciTech Connect

    Maggiore, M. Cavenago, M.; Comunian, M.; Chirulotto, F.; Galatà, A.; De Lazzari, M.; Porcellato, A. M.; Roncolato, C.; Stark, S.; Caruso, A.; Longhitano, A.; Cavaliere, F.; Maero, G.; Paroli, B.; Pozzoli, R.; Romé, M.

    2014-02-15

    Two linear trap devices for particle beam manipulation (including emittance reduction, cooling, control of instabilities, dust dynamics, and non-neutral plasmas) are here presented, namely, a radiofrequency quadrupole (RFQ) beam cooler and a compact Penning trap with a dust injector. Both beam dynamics studies by means of dedicated codes including the interaction of the ions with a buffer gas (up to 3 Pa pressure), and the electromagnetic design of the RFQ beam cooler are reported. The compact multipurpose Penning trap is aimed to the study of multispecies charged particle samples, primarily electron beams interacting with a background gas and/or a micrometric dust contaminant. Using a 0.9 T solenoid and an electrode stack where both static and RF electric fields can be applied, both beam transport and confinement operations will be available. The design of the apparatus is presented.

  10. Charge and quadrupole fluctuations and gap anisotropy in BiS2-based superconductors

    NASA Astrophysics Data System (ADS)

    Suzuki, Katsuhiro; Usui, Hidetomo; Kuroki, Kazuhiko; Ikeda, Hiroaki

    2017-07-01

    Recent angle-resolved spectroscopy in BiS2-based superconductors has indicated that the superconducting gap amplitude possesses remarkable anisotropy and/or a sign change on a small Fermi pocket around the X point. It implies a possibility of an unconventional pairing state. Here we study the gap anisotropy in superconductivity mediated by inherent charge and quadrupole fluctuations in an extended Hubbard model, which includes intersite interaction between Bi and S atoms. The first-principles downfolded band structure is composed of Bi 6 px/py and S 3 px/py orbitals on a BiS2 single layer. Evaluating the linearized gap equation, we find that the ferroic charge and quadrupole fluctuation driven by the intersite interaction leads to a fully gapped dx2-y2-wave pairing state, in which the gap amplitude has sizable anisotropy on the Fermi surface.

  11. Orientational mechanisms in liquid crystalline systems. 2. The contribution to solute ordering from the reaction field interaction between the solute electric quadrupole moment and the solvent electric field gradient.

    PubMed

    Celebre, Giorgio; Ionescu, Andreea

    2010-01-14

    In the previous paper of this issue, [Celebre, G.; Ionescu, A. J. Phys. Chem. B doi: 10.1021/jp907310g], following a generalized reaction field approach in the linear response approximation, we were successful in obtaining an analytical compact expression for the mean-field anisotropic orientational potential U(Q-EFG) theoretically experienced by a highly idealized nonionic and apolar solute, considered as a point quadrupole immersed in a uniaxial polarizable continuum medium (model of a nematic solvent comprised of dipolar mesogenic molecules). The term U(Q-EFG) describes the electrostatic interaction between the electric quadrupole of the solute and the electric field gradient induced at the solute by the surrounding medium polarized by the distribution of electric charges representing the quadrupolar solute itself. In the present paper, the obtained potential has been considered as an additional orientational interaction contributing to the solute ordering, besides the well-recognized and very effective "short-range" (size-and-shape-dictated) mechanisms. Since in our theory the solvent is characterized by its dielectric tensor, the model has been widely tested by taking as references the experimental order parameters of several uniaxial and biaxial different small rigid probe molecules (H(2), N(2), acetylene, allene, propyne, benzene, hexafluorobenzene, 1,4-difluorobenzene, and norbornadiene) dissolved in the nematic solvents ZLI1132 (Deltaepsilon > 0) and EBBA (Deltaepsilon < 0); moreover, the order parameters of the same solutes in the so-called nematic "magic mixture" (45 wt % EBBA + 55 wt % ZLI1132), where the short-range orientational effects are commonly believed to be very dominant, have been conventionally assumed as reference of the absence of electrostatic orientational effects. The experimental order parameters of the treated solutes, obtained in the past by liquid crystal NMR and available from literature, have been then compared with those

  12. Computational Study on the Stacking Interaction in Catechol Complexes

    NASA Astrophysics Data System (ADS)

    Estévez, Laura; Otero, Nicolás; Mosquera, Ricardo A.

    2009-09-01

    The stability and electron density topology of catechol complexes (dimers and tetramer) were studied using the MPW1B95 functional. The QTAIM analysis shows that both dimers (face to face and C-H/π one) display a different electronic origin. The formation of the former is accompanied by a significant change in the values of atomic electron dipole and quadrupole components, flattening the most diffuse part of the electron density distribution toward the molecular plane. A small electron population transfer is observed between catechol monomers connected by C-H/π interactions, whose QTAIM characterization does not differ from that of a weak hydrogen bond. Cooperative effects in the tetramer on binding energies are small and negligible for bond properties and charge transfer. Nevertheless, they are significant on atomic electron populations.

  13. Study of the matrix effects of tetrodotoxin and its content in cooked seafood by liquid chromatography with triple quadrupole mass spectrometry.

    PubMed

    Xu, Xiao-min; Yu, Xin-wei; Lu, Meiling; Huang, Bai-fen; Ren, Yi-ping

    2015-10-01

    Tetrodotoxin is a marine biotoxin with high acute toxicity. The levels in cooked seafood will help us to assess its intake in humans and may help assess the risk of toxicity. However, heavy matrices hinder the direct quantitation of tetrodotoxin. A quantitative method of measuring tetrodotoxin in cooked seafood using liquid chromatography with triple quadrupole mass spectrometry was established in this study. Tetrodotoxin was extracted from the sample matrix using 2% formic acid in methanol and cleaned using a cation exchange cartridge. The cleanup conditions were optimized. The matrix effects were determined using the postextraction spiking method and by comparing the slope of the linear regression equation in sample matrix to that in solvent. The limit of detection in the sample matrix was 5 μg/kg and the limit of quantification was 10 μg/kg. The mean recoveries at three spiking levels were 66.9-89.2% with relative standard deviations of 5.0-10.8% (n = 6) in five different matrices. Tetrodotoxin was found at concentrations of 26.1-2462 μg/kg in nine of 83 cooked seafoods tested in this study. Eight analogs of Tetrodotoxin were detected in the samples studied. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Quadrupole Moments of odd-A 53-63Mn: First use of optical pumping in the ISOLDE cooler/buncher

    NASA Astrophysics Data System (ADS)

    Babcock, Carla; Collaps Collaboration

    2016-09-01

    The technique of optical pumping has been used in the ISOLDE (CERN) cooler/buncher ion trap in order to study the previously inaccessible quadrupole moments of neutron-rich manganese ions via collinear laser spectroscopy. Previously, the insensitivity of the ground state atomic transitions to the quadrupole interaction prevented the determination of the electric quadrupole moment with any reasonable accuracy. Instead, a transition from an ionic metastable state was used and this state was populated via optical pumping. This was done in the bunching region of the ion trap, to allow multiple laser-ion interactions. Spectroscopic quadrupole moments were measured for the odd-even isotopes in the range 53-63Mn. They were compared to the predictions of three modern shell model effective interactions. The inclusion of both the 1 νg9 / 2 and 2 νd5 / 2 orbitals in the model space was thus shown to be necessary to reproduce the observed increase in the quadrupole deformation from N = 36 onwards. Specifically, the inclusion of the 2 νd5 / 2 orbital induces an increase in neutron and proton excitations across the proposed gaps at N = 40 and Z = 28 , leading to an increase in deformation in the more neutron-rich isotopes.

  15. Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in 248Cm samples for transmutation studies

    SciTech Connect

    Gourgiotis, A.; Isnard, H.; Aubert, M.; Dupont, E.; AlMahamid, I.; Cassette, P.; Panebianco, S.; Letourneau, A.; Chartier, F.; Tian, G.; Rao, L.; Lukens, W.

    2011-02-01

    The French Atomic Energy Commission has carried out several experiments including the mini-INCA (INcineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in {sup 248}Cm ({approx}97 %) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This work describes a quadrupole ICP-MS (ICP-QMS) analytical procedure for precise and accurate isotopic composition determination of Cm before sample irradiation and of Cm and Cf after sample irradiation. The factors that affect the accuracy and reproducibility of isotopic ratio measurements by ICP-QMS, such as peak centre correction, detector dead time, mass bias, abundance sensitivity and hydrides formation, instrumental background, and memory blank were carefully evaluated and corrected. Uncertainties of the isotopic ratios, taking into account internal precision of isotope ratio measurements, peak tailing, and hydrides formations ranged from 0.3% to 1.3%. This uncertainties range is quite acceptable for the nuclear data to be used in transmutation studies.

  16. Comparative study of electrospray and photospray ionization sources coupled to quadrupole time-of-flight mass spectrometer for olive oil authentication.

    PubMed

    Gómez-Ariza, J L; Arias-Borrego, A; García-Barrera, T; Beltran, R

    2006-11-15

    The use of fast and reliable analytical procedures for olive oil authentication is a priority demand due to its wide consumption and healthy benefits. Olive oil adulteration with other cheaper vegetable oils is a common practice that has to be detected and controlled. Rapid screening methods based on high resolution tandem mass spectrometry constitute today the option of choice due to sample handling simplicity and the elimination of the chromatographic step. The selection of the ionization source is critical and the comparison of their reliability necessary. The possibilities of the direct infusion electrospray ionization (ESI) and the recently introduced atmospheric pressure photospray ionization source (APPI), coupled to quadrupole time-of-flight (QqTOF), have been critically studied and compared to control olive oil adulteration. These techniques are very rapid (approximately 1min per sample) and have high discrimination power to elucidate key components in the edible oils studied (olive, hazelnut, sunflower and corn). Nevertheless, both sources are complementary, being APPI more sensitive for monoacyl- and diacylglycerol fragment ions and ESI for triacylglycerols. In addition, methods reproducibility's are very high, especially for APPI source. Mixtures of olive oil with the others vegetable oils can be easily discriminated which has been tested by using principal components analysis (PCA) with both ESI-MS and APPI-MS spectra. Analogously, linear discriminant analysis (LDA) confirms methods reproducibility and detection of other oils used as adulterants, in particular hazelnut oil, which is especially difficult given its chemical similarity with olive oil.

  17. Urinary metabolomic study of non-small cell lung carcinoma based on ultra high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

    PubMed

    Wu, Qian; Wang, Yan; Gu, Xue; Zhou, Junyi; Zhang, Huiping; Lv, Wang; Chen, Zhe; Yan, Chao

    2014-07-01

    Metabolic profiles from human urine reveal the significant difference of carnitine and acylcarnitines levels between non-small cell lung carcinoma patients and healthy controls. Urine samples from cancer patients and healthy individuals were assayed in this metabolomic study using ultra high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. The data were normalized by the sum of all intensities and creatinine calibration, respectively, before orthogonal partial least squares discriminant analysis. Twenty differential metabolites were identified based on standard compounds or tandem mass spectrometry fragments. Among them, some medium-/long-chain acylcarnitines, for example, cis-3,4-methylene heptanoylcarnitine, were found to be downregulated while carnitine was upregulated in urine samples from the cancer group compared to the control group. Receiver operating characteristic analysis of the two groups showed that the area under curve for the combination of carnitine and 11 selected acylcarnitines was 0.958. This study suggests that the developed carnitine and acylcarnitines profiling method has the potential to be used for screening non-small cell lung carcinoma.

  18. Tissue distribution and excretion study of neopanaxadiol in rats by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry.

    PubMed

    Geng, Cong; Yin, Jian-yuan; Yu, Xiu-hua; Liu, Jing-yan; Yang, Yu-xia; Sun, De-ya; Meng, Qin; Wei, Zhong-lin; Liu, Ji-hua

    2015-03-01

    Neopanaxadiol (NPD), a major ginsenoside in Panax ginseng C. A. Meyer (Araliaceae), was reported to have neuroprotective effect. In this study, a method of ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC/QTOF-MS) was developed and validated for quantitative analysis of NPD in tissues, urine and feces, using liquid-liquid extraction (LLE) to isolate NPD from different biological samples, and chromatographic separation was performed on an Agilent Zorbax Stable Bond C18 (2.1 × 50 mm, 1.8 µm) column with 0.1% formic acid in water and acetonitrile. All standard calibration curves were linear (all r(2) > 0.995) within the test range. After oral administration, NPD was extensively distributed to most of the tissues without long-term accumulation. The higher levels were observed in stomach and intestine, followed by kidney and liver. Approximately 64.56 ± 20.32% of administered dose in feces and 0.0233 ± 0.0356% in urine were found within 96 h, which indicated that the major elimination route was fecal excretion. This analytical method was applied to the study of NPD distribution and excretion in rats after oral intake for the first time. The results we found here are helpful for us to understand the pharmacological effects of NPD, as well as its toxicity. Copyright © 2014 John Wiley & Sons, Ltd.

  19. Metabolism profiles of icariin in rats using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry and in vitro enzymatic study.

    PubMed

    Cheng, Tao; Sheng, Tingting; Yi, Yaxiong; Zhang, Tong; Han, Han

    2016-10-15

    Icariin (ICA), the major constituent of Epimedium brevicornu Maxim, is recognized as an effective agent for the treatment of osteoporosis. In our previous report, the relatively short half-life (74min) and poor bioavailability (approximately 0.1%) of ICA in rats suggested that not only ICA itself but also its metabolites could be responsible for the observed osteoporosis treatment effect. Therefore, the present study aimed at identifying the metabolites of ICA in rat plasma, bile, urine, and feces after the administration of a single oral dose of ICA (150mg/kg). In this work, ultra-high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC/Q-TOF-MS) method was established to identify the metabolic profiles following intragastric administration of pure ICA in rats. The blood, bile, urine, and feces samples of the rats were investigated to explore the complete metabolic pathway of ICA in vivo. A total of 14 metabolites were detected in the bile, revealing that the bile is the main excretion pathway for ICA and its metabolites. The conjugated metabolites as observed in vivo, was further confirmed by the in vitro enzymatic study. Five metabolites of ICA, including demethylicariin, icariside I-3-O-glucuronide, demethylicariside II, demethylicariside II-7-O-glucuronide, and dehydroxyicaritin-glucuronide, were reported for the first time in the literature. In addition, the results revealed that the principal metabolism pathways of ICA in rat were deglycosylation and glucuronidation after deglycosylation.

  20. Metabolomics study on primary dysmenorrhea patients during the luteal regression stage based on ultra performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry

    PubMed Central

    Fang, Ling; Gu, Caiyun; Liu, Xinyu; Xie, Jiabin; Hou, Zhiguo; Tian, Meng; Yin, Jia; Li, Aizhu; Li, Yubo

    2017-01-01

    Primary dysmenorrhea (PD) is a common gynecological disorder which, while not life-threatening, severely affects the quality of life of women. Most patients with PD suffer ovarian hormone imbalances caused by uterine contraction, which results in dysmenorrhea. PD patients may also suffer from increases in estrogen levels caused by increased levels of prostaglandin synthesis and release during luteal regression and early menstruation. Although PD pathogenesis has been previously reported on, these studies only examined the menstrual period and neglected the importance of the luteal regression stage. Therefore, the present study used urine metabolomics to examine changes in endogenous substances and detect urine biomarkers for PD during luteal regression. Ultra performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry was used to create metabolomic profiles for 36 patients with PD and 27 healthy controls. Principal component analysis and partial least squares discriminate analysis were used to investigate the metabolic alterations associated with PD. Ten biomarkers for PD were identified, including ornithine, dihydrocortisol, histidine, citrulline, sphinganine, phytosphingosine, progesterone, 17-hydroxyprogesterone, androstenedione, and 15-keto-prostaglandin F2α. The specificity and sensitivity of these biomarkers was assessed based on the area under the curve of receiver operator characteristic curves, which can be used to distinguish patients with PD from healthy controls. These results provide novel targets for the treatment of PD. PMID:28098892

  1. Electronic coupling calculations with transition charges, dipoles, and quadrupoles derived from electrostatic potential fitting

    SciTech Connect

    Fujimoto, Kazuhiro J.

    2014-12-07

    A transition charge, dipole, and quadrupole from electrostatic potential (TrESP-CDQ) method for electronic coupling calculations is proposed. The TrESP method is based on the classical description of electronic Coulomb interaction between transition densities for individual molecules. In the original TrESP method, only the transition charge interactions were considered as the electronic coupling. In the present study, the TrESP method is extended to include the contributions from the transition dipoles and quadrupoles as well as the transition charges. Hence, the self-consistent transition density is employed in the ESP fitting procedure. To check the accuracy of the present approach, several test calculations are performed to a helium dimer, a methane dimer, and an ethylene dimer. As a result, the TrESP-CDQ method gives a much improved description of the electronic coupling, compared with the original TrESP method. The calculated results also show that the self-consistent treatment to the transition densities contributes significantly to the accuracy of the electronic coupling calculations. Based on the successful description of the electronic coupling, the contributions to the electronic coupling are also analyzed. This analysis clearly shows a negligible contribution of the transition charge interaction to the electronic coupling. Hence, the distribution of the transition density is found to strongly influence the magnitudes of the transition charges, dipoles, and quadrupoles. The present approach is useful for analyzing and understanding the mechanism of excitation-energy transfer.

  2. Multiband Superconductivity in Filled-Skutterudite Compounds (Pr1-xLax)Os4Sb12: An Sb Nuclear-Quadrupole-Resonance Study

    NASA Astrophysics Data System (ADS)

    Yogi, Mamoru; Nagai, Takayuki; Imamura, Yojyu; Mukuda, Hidekazu; Kitaoka, Yoshio; Kikuchi, Daisuke; Sugawara, Hitoshi; Aoki, Yuji; Sato, Hideyuki; Harima, Hisatomo

    2006-12-01

    for weak-coupling BCS s-wave superconductors. With increasing Pr content, Tc increases and the energy gap increases from 2Δ0/kBTc=3.45 for pure La compounds up to 2Δ0/kBTc=4.2 and 5.2 for the 60% Pr and 80% Pr compounds, respectively. The Pr substitution for La enhances the pairing interaction and induces an anisotropy in the energy-gap structure. The novel strong-coupling superconductivity in PrOs4Sb12 is inferred to be mediated by the local interaction between 4 f2-derived crystal-electric-field states with the electric quadrupole degree of freedom and conduction electrons. This coupling causes a mass enhancement of quasi-particles for a part of FS and induces a small FS, which is responsible for point nodes in the superconducting gap function. Note that the small FS does not play any primary role for the strong-coupling superconductivity in PrOs4Sb12.

  3. Precise calculations of the deuteron quadrupole moment

    SciTech Connect

    Gross, Franz L.

    2016-06-01

    Recently, two calculations of the deuteron quadrupole moment have have given predictions that agree with the measured value to within 1%, resolving a long-standing discrepancy. One of these uses the covariant spectator theory (CST) and the other chiral effective field theory (cEFT). In this talk I will first briefly review the foundations and history of the CST, and then compare these two calculations with emphasis on how the same physical processes are being described using very different language. The comparison of the two methods gives new insights into the dynamics of the low energy NN interaction.

  4. Coil Creep and Skew-Quadrupole Field Components in the Tevatron

    SciTech Connect

    Annala, G.; Harding, D.J.; Syphers, M.J.; /Fermilab

    2011-07-11

    During the start-up of Run II of the Tevatron Collider program, several issues surfaced which were not present, or not seen as detrimental, during Run I. These included the repeated deterioration of the closed orbit requiring orbit smoothing every two weeks or so, the inability to correct the closed orbit to desired positions due to various correctors running at maximum limits, regions of systematically strong vertical dipole corrections, and the identification of very strong coupling between the two transverse degrees-of-freedom. It became apparent that many of the problems being experienced operationally were connected to a deterioration of the main dipole magnet alignment, and remedial actions were undertaken. However, the alignment alone was not enough to explain the corrector strengths required to handle transverse coupling. With one exception, strong coupling had generally not been an issue in the Tevatron during Run I. Based on experience with the Main Ring, the Tevatron was designed with a very strong skew quadrupole circuit to compensate any quadrupole alignment and skew quadrupole field errors that might present themselves. The circuit was composed of 48 correctors placed evenly throughout the arcs, 8 per sector, evenly placed in every other cell. Other smaller circuits were installed but not initially needed or commissioned. These smaller circuits were composed of individual skew quadrupole correctors on either side of the long straight sections. These circuits were tuned by first bringing the horizontal and vertical tunes near each other. The skew quadrupoles were then adjusted to minimize tune split, usually to less than 0.003. Initially, the main skew quad circuit (designated T:SQ) could accomplish this global decoupling with only 4% of its possible current, and the smaller circuits were not required at all. The start-up of Run Ib was complicated by what was later discovered to be a rolled triplet quadrupole magnet in one of the Interaction Regions

  5. Enhanced quadrupole effects for atoms in optical vortices.

    PubMed

    Lembessis, V E; Babiker, M

    2013-02-22

    We show that the normally weak optical quadrupole interaction in atoms is enhanced significantly when the atom interacts at near resonance with an optical vortex. In particular, the forces and torque acting on the atom are shown here to scale up with the square of the winding number l of the vortex. Because the integer l can be arranged to be large, this property allows for processes involving dipole-forbidden, but quadrupole-allowed, transitions in atoms, such as cesium and oxygen, to come into play. We show that the mechanical effects of vortex light on atoms involving translational and rotational motion as well as trapping should be significantly enhanced for quadrupole transitions and present novel features with useful implications for the emerging field of atomtronics.

  6. LARP Long Nb3Sn Quadrupole Design.

    SciTech Connect

    Ambrosio,G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Chlachidize, G.; Dietderich, D.; Feher, S.; Felice, H.; Ferracin, P.; Ghosh, A.; Hafalia, A.R.; Hannaford, C.R.; Kashikhin, V.V.; Kerby, J.; Lamm, M.; Lietzke, A.; McInturff, A.; Muratore, J.; Nobrega, F.; Novitsky, I.; Sabbi, G.L.; Schmalzle, J.; Tartaglia, M.; Turrioni, D.; Wanderer, P.; Whitson, G.; Zlobin, A.V.

    2007-08-27

    A major milestone for the LHC Accelerator Research Program (LARP) is the test, by the end of 2009, of two 4m-long quadrupole magnets (LQ) wound with Nb{sub 3}Sn conductor. The goal of these magnets is to be a proof of principle that Nb{sub 3}Sn is a viable technology for a possible LHC luminosity upgrade. The design of the LQ is based on the design of the LARP Technological Quadrupoles, presently under development at FNAL and LBNL, with 90-mm aperture and gradient higher than 200 T/m. The design of the first LQ model will be completed by the end of 2007 with the selection of a mechanical design. In this paper we present the coil design addressing some fabrication technology issues, the quench protection study, and three designs of the support structure.

  7. LARP Long Nb3Sn Quadrupole Design

    SciTech Connect

    Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Chlachidize, G.; Dietderich, D.; Feher, S.; Ferracin, P.; Ghosh, A.; Hafalia, R.; Hannaford, R.; Kashikhin, V.V.; Kerby, J.; Lamm, M.; Lietzke, A.; McInturff, A.; Muratore, J.; Nobrega, F.; Novitsky, I.; Sabbi, G.L.; Schmalzle, J.; Tartaglia, M.; Turrioni, D.; Wanderer, P.; Whitson, G.; Zlobin, A.V.

    2008-06-01

    A major milestone for the LHC Accelerator Research Program (LARP) is the test, by the end of 2009, of two 4m-long quadrupole magnets (LQ) wound with Nb{sub 3}Sn conductor. The goal of these magnets is to be a proof of principle that Nb{sub 3}Sn is a viable technology for a possible LHC luminosity upgrade. The design of the LQ is based on the design of the LARP Technological Quadrupoles, presently under development at FNAL and LBNL, with 90-mm aperture and gradient higher than 200 T/m. The design of the first LQ model will be completed by the end of 2007 with the selection of a mechanical design. In this paper we present the coil design addressing some fabrication technology issues, the quench protection study, and three designs of the support structure.

  8. LARP Long Nb3Sn Quadrupole Design

    SciTech Connect

    Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Chlachidze, G.; Dietderich, D.; Feher, S.; Felice, H.; Ferracin, P.; /Fermilab /Brookhaven /LBL, Berkeley /Texas A-M

    2007-08-01

    A major milestone for the LHC Accelerator Research Program (LARP) is the test, by the end of 2009, of two 4m-long quadrupole magnets (LQ) wound with Nb3Sn conductor. The goal of these magnets is to be a proof of principle that Nb3Sn is a viable technology for a possible LHC luminosity upgrade. The design of the LQ is based on the design of the LARP Technological Quadrupoles, presently under development at FNAL and LBNL, with 90-mm aperture and gradient higher than 200 T/m. The design of the first LQ model will be completed by the end of 2007 with the selection of a mechanical design. In this paper we present the coil design addressing some fabrication technology issues, the quench protection study, and three designs of the support structure.

  9. Quadrupole Induced Resonant Particle Transport

    NASA Astrophysics Data System (ADS)

    Gilson, Erik; Fajans, Joel

    1999-11-01

    We have performed experiments that explore the effects of a magnetic quadrupole field on a pure electron plasma confined in a Malmberg-Penning trap. A model that we have developed describes the shape of the plasma and shows that a certain class of resonant particles follows trajectories that take them out of the plasma. Even though the quadrupole field destroys the cylindrical symmetry of the system, our theory predicts that if the electrons are off resonance, then the lifetime of the plasma will not be greatly affected by the quadrupole field. Our preliminary experimental results show that the shape of the plasma and the plasma lifetime agree with our model. We are investigating the scaling of this behavior with various experimental parameters such as the plasma length, density, and strength of the quadrupole field. In addition to being an example of resonant particle transport, this effect may find practical applications in experiments that plan to use magnetic quadrupole neutral atom traps to confine anti-hydrogen created in double-well positron/anti-proton Malmberg-Penning traps. (ATHENA Collaboration.)

  10. Quadrupole Induced Resonant Particle Transport

    NASA Astrophysics Data System (ADS)

    Gilson, Erik; Fajans, Joel

    1998-11-01

    We have performed experiments that explore the effects of a magnetic quadrupole field on a pure electron plasma confined in a Penning-Malmberg trap. A model that we have developed describes the shape of the plasma and shows that a certain class of resonant particles follows trajectories that take them out of the plasma. Even though the quadrupole field destroys the cylindrical symmetry of the system, our theory predicts that if the electrons are off resonance, then the lifetime of the plasma will not be greatly affected by the quadrupole field. Our preliminary experimental results show that the shape of the plasma and the plasma lifetime agree with our model. We are investigating the scaling of this behavior with various experimental parameters such as the plasma length, density, and strength of the quadrupole field. In addition to being an example of resonant particle transport, this effect may find practical applications in experiments that plan to use magnetic quadrupole neutral atom traps to confine anti-hydrogen created in double-well positron/anti-proton Penning-Malmberg traps. (ATHENA Collaboration.)

  11. Study of bis(bibenzyls) in bryophytes using electron ionization time-of-flight and electrospray ionization triple-quadrupole mass spectrometry.

    PubMed

    Guo, Huaifang; Xing, Jie; Xie, Chunfeng; Qu, Jianbo; Gao, Yanhui; Lou, Hongxiang

    2007-01-01

    A detailed analysis of mass spectra generated from bis(bibenzyl) compounds in bryophytes under electron ionization time-of-flight (EI-TOF) and electrospray ionization triple-quadrupole (ESI-TQ) mass spectrometry conditions is reported. Proposed structures of the fragment ions were obtained by tracking the functional groups of 15 bis(bibenzyls), the structures of which are similar except for some alkoxyl substituents and linkage sites of biphenyl ether bonds. The elucidation was aided by the use of accurate mass measurements. Attempts have been made to provide rational pathways for the formation of these fragment ions, and a generalized fragmentation mechanism is proposed. The bis(bibenzyls) mentioned in this study include three types according to their structure characteristics, i.e. one biphenyl ether bond (A-type), two biphenyl ether bonds (B-type), one biphenyl ether and one biphenyl bond (C-type). The three types display different EI-MS and ESI-MS/MS product profiles, by which the bis(bibenzyl) type and the number of alkoxyl substituents can be identified. Isomers of bis(bibenzyls) can be differentiated to some extent, while the linkage sites of biphenyl ether bonds are difficult to identify. The structure-fragmentation relationships will facilitate the characterization of other bis(bibenzyls) and this will be of value for the high-throughput screening of novel bis(bibenzyls) in bryophytes.

  12. Metabolism studies on prim-O-glucosylcimifugin and cimifugin in human liver microsomes by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry.

    PubMed

    Jia, Peipei; Zhang, Yuqian; Zhang, Qiaoyue; Sun, Yupeng; Yang, Haotian; Shi, He; Zhang, Xiaoxu; Zhang, Lantong

    2016-09-01

    Prim-O-glucosylcimifugin (PGCN) and cimifugin (CN) are major constituents of Radix Saposhnikoviae that have antipyretic, analgesic and anti-inflammatory pharmacological activities. However, there were few reports with respect to the metabolism of PGCN and CN in vitro. In this paper, we describe a strategy using ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) for fast analysis of the metabolic profile of PGCN and CN in human liver microsomes. In total, five phase I metabolites of PGCN, seven phase I metabolites and two phase II metabolites of CN were identified in the incubation of human liver microsomes. The results revealed that the main phase I metabolic pathways of PGCN were hydroxylation and hydrolysis reactions. The phase I metabolic pathways of CN were found to be hydroxylation, demethylation and dehydrogenation. Meanwhile, the results indicated that O-glucuronidation was the major metabolic pathway of CN in phase II metabolism. The specific UDP-glucuronosyltransferase (UGT) enzymes responsible for CN glucuronidation metabolites were identified using recombinant UGT enzymes. The results indicated that UGT1A1, UGT1A9, UGT2B4 and UGT2B7 might play major roles in the glucuronidation of CN. Overall, this study may be useful for the investigation of metabolic mechanism of PGCN and CN, and it can provide reference and evidence for further pharmacodynamic experiments. Copyright © 2016 John Wiley & Sons, Ltd.

  13. An analytical method for estimating the {sup 14}N nuclear quadrupole resonance parameters of organic compounds with complex free induction decays for radiation effects studies

    SciTech Connect

    Iselin, L.H.

    1992-12-31

    The use of {sup 14}N nuclear quadrupole resonance (NQR) as a radiation dosimetry tool has only recently been explored. An analytical method for analyzing {sup 14}N NQR complex free induction decays is presented with the background necessary to conduct pulsed NQR experiments. The {sup 14}N NQR energy levels and possible transitions are derived in step-by-step detail. The components of a pulsed NQR spectrometer are discussed along with the experimental techniques for conducting radiation effects experiments using the spectrometer. Three data analysis techniques -- the power spectral density Fourier transform, state space singular value decomposition (HSVD), and nonlinear curve fitting (using the downhill simplex method of global optimization and the Levenberg-Marquart method) -- are explained. These three techniques are integrated into an analytical method which uses these numerical techniques in this order to determine the physical NQR parameters. Sample data sets of urea and guanidine sulfate data are used to demonstrate how these methods can be employed to analyze both simple and complex free induction decays. By determining baseline values for biologically significant organics, radiation effects on the NQR parameters can be studied to provide a link between current radiation dosimetry techniques and the biological effects of radiation.

  14. Comparative study of Eucalyptus dunnii volatile oil composition using retention indices and comprehensive two-dimensional gas chromatography coupled to time-of-flight and quadrupole mass spectrometry.

    PubMed

    von Mühlen, Carin; Zini, Claudia Alcaraz; Caramão, Elina Bastos; Marriott, Philip J

    2008-07-18

    In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied using comprehensive two-dimensional gas chromatography (GCxGC) techniques. Structurally related compounds were found to elute mainly in specific regions of the two-dimensional space, showing orderly distribution with chemical class. Mass spectra of essential oil components were obtained from two different mass spectrometry detection methods: quadrupole (qMS) and time-of-flight (TOFMS), using the same GCxGC system under the same chromatographic conditions. Higher values of Similarity (average S of 914 with TOFMS compared to 880 with qMS) and Reverse (average R of 944 with TOFMS compared to 881 with qMS) were obtained with GCxGC/TOFMS showing its superior performance, which was most likely due to better sensitivity and resolution arising from the TOFMS system, and lack of spectral bias. Also, the number of compounds found in E. dunnii essential oil was 15% higher when TOFMS was used. Most of these are lower abundance components or exhibit low quality mass spectra; this supports the improved sensitivity obtained with TOFMS. A linear relationship (r2=0.998) between experimental retention indices (LTPRI) of 30 standard compounds obtained with GCxGC/TOFMS and GC with flame ionization detection literature retention indices is reported as an aid for compound identification.

  15. A study of 75Se by neutron capture and the SU(3)-SU(5) transition in the quadrupole-phonon representation

    NASA Astrophysics Data System (ADS)

    Tokunaga, Y.; Seyfarth, H.; Schult, O. W. B.; Brant, S.; Paar, V.; Vretenar, D.; Borner, H. G.; Barreau, G.; Faust, H.; Hofmeyr, Ch.; Schreckenbach, K.; Meyer, R. A.

    1984-11-01

    The γ and e - spectra following thermal neutron capture in 74Se were studied with curved-crystal, β, and pair spectrometers. Precise energies have been obtained for the transitions and levels at low energies. Two primary E2 transitions were found. The neutron separation energy for 75Se was determined as 8027.6 keV. Precise γ-energies following the electron capture decay of 75Se were also measured, resulting in precise level energies in 75As. The calculation of the energy levels in 75Se has been performed in the SU(6) particle-vibrational model (PTQM) and 27 theoretical states have been tentatively assigned to the experimental levels. The spectrum of the core nucleus 74Se has been calculated in the SU(6) quadrupolephonon model (TQM). The structure of theoretical states, the relation to SU(3) and SU(5) limits, and potential energy surface are discussed. The E2, M1 and E1 transitions have been calculated in PTQM and compared to the experiment. Also, an overview is presented of theoretical explanations of the I = j, j-1, j-2 anomalous triplet emphasizing the rule with shell-model classification corrected for quadrupole phonons.

  16. Combining Fourier transform nuclear quadrupole resonance (FT-NQR) spectroscopy and mass spectrometry (MS) to study the electronic structure of titanocene dichlorides.

    PubMed

    Kubišta, Jiří; Civiš, Martin; Spaněl, Patrik; Civiš, Svatopluk

    2012-03-21

    A combination of nuclear quadrupole resonance spectroscopy (NQR) and mass spectrometry (MS) has been used to observe trends in electronic structure in three titanocenes: bis(cyclopentadienyl) titanium dichloride (η(5)-C(5)H(5))(2)TiCl(2), bis(pentamethylcyclopentadienyl) titanium dichloride (η(5)-C(5)(CH(3))(5))(2)TiCl(2) and dimethylsilylene-bridged ansa bis(cyclopentadienyl) titanium dichloride Si(CH(3))(2)(η(5)-C(5)H(5))(2)TiCl(2). Using MS, electron ionisation mass spectra of these compounds are presented within the context of the entire homologous series with one to five methyl groups on each cyclopentadienyl ligand. A dedicated NQR spectrometer was constructed for this study with a sensitivity sufficient to precisely determine the NQR resonant frequency of (35)Cl atoms using 3 g samples of these titanocenes. The observed frequencies are thus 11.784, 11.930 and 10.863 MHz at 298 K. The results demonstrate that NQR using a relatively simple apparatus can be used as a sensitive and cost effective probe into the molecular structure of organometallic chlorides, which complements the information inferred from the mass spectra.

  17. On-line combination of high performance liquid chromatography with comprehensive two-dimensional gas chromatography-triple quadrupole mass spectrometry: a proof of principle study.

    PubMed

    Zoccali, Mariosimone; Tranchida, Peter Quinto; Mondello, Luigi

    2015-02-03

    The present contribution is focused on the on-line combination of high performance liquid chromatography (HPLC), cryogenically modulated comprehensive two-dimensional gas chromatography (GC × GC), and triple quadrupole mass spectrometry (QqQ MS), generating a very powerful unified separation-science tool. The instrument can be used in seven different combinations ranging from one-dimensional HPLC with a photodiode array detector to on-line LC × GC × GC/QqQ MS. The main focus of the present research is directed to the LC-GC × GC/QqQ MS configuration, with its analytical potential shown in a proof-of-principle study involving a very complex sample, namely, coal tar. Specifically, a normal-phase LC process enabled the separation of three classes of coal tar compounds: (1) nonaromatic hydrocarbons; (2) unsaturated compounds (with and without S); (3) oxygenated constituents. The HPLC fractions were transferred to the GC × GC instrument via a syringe-based interface mounted on an autosampler. Each fraction was subjected to a specific programmed temperature vaporizer GC × GC/QqQ MS untargeted or targeted analysis. For example, the coal tar S-containing compounds were pinpointed through multiple-reaction-monitoring analysis, while full-scan information was attained for the oxygenated constituents.

  18. Quadrupole moment of 203Fr

    NASA Astrophysics Data System (ADS)

    Wilkins, S. G.; Lynch, K. M.; Billowes, J.; Binnersley, C. L.; Bissell, M. L.; Cocolios, T. E.; Goodacre, T. Day; de Groote, R. P.; Farooq-Smith, G. J.; Flanagan, K. T.; Franchoo, S.; Ruiz, R. F. Garcia; Gins, W.; Heylen, H.; Koszorús, Á.; Neyens, G.; Stroke, H. H.; Vernon, A. R.; Wendt, K. D. A.; Yang, X. F.

    2017-09-01

    The spectroscopic electric quadrupole moment of the neutron-deficient francium isotope 203Fr was measured by using high-resolution collinear resonance ionization spectroscopy (CRIS) at the CERN Isotope Separation On-Line Device (ISOLDE) facility. A remeasurement of the 207Fr quadrupole moment was also performed, resulting in a departure from the established literature value. A sudden increase in magnitude of the 203Fr quadrupole moment, with respect to the general trend in the region, points to an onset of static deformation at N =116 in the 87Fr isotopic chain. Calculation of the static and total deformation parameters show that the increase in static deformation only cannot account for the observed departure of its relative charge radius from the 82Pb chain.

  19. Development of a comprehensive two-dimensional hydrophilic interaction chromatography/quadrupole time-of-flight mass spectrometry system and its application in separation and identification of saponins from Quillaja saponaria.

    PubMed

    Wang, Yuan; Lu, Xin; Xu, Guowang

    2008-02-15

    Hydrophilic interaction chromatography (HILIC) was used in two dimensions in a comprehensive two-dimensional HILIC hyphenated with a quadrupole time-of-flight mass spectrometry (HILICxHILIC-Q-TOF-MS) system for the analysis of complex samples of hydrophilic compounds. A TSKgel Amide-80 column was employed as the first dimension, and a short PolyHydroxyethyl A column was as the second dimension. The column system showed moderate orthogonality at defined operational conditions. A high speed Q-TOF-MS detector as a third complementary dimension significantly improved the peak capacity. The separation capability of the developed HILICxHILIC-Q-TOF-MS system was tested by separating an extract from Quillaja saponaria. The major components, quillaja saponins, in the extract were well identified by means of [M-H](-) ions, characteristic product ions, and their two-dimensional retention behaviors. Several pairs of isomers, which were often co-eluted on conventional LC-MS methods and had similar fragmentation characteristics in MS/MS spectra, were well separated on the two-dimensional system based on their different hydrophilicity. The developed comprehensive two-dimensional HILIC system demonstrates unique selectivity for hydrophilic compounds and satisfactory peak capacity and resolution for analogues by making sufficient use of two-dimensional separation plane.

  20. Chemometrics for comprehensive analysis of nucleobases, nucleosides, and nucleotides in Siraitiae Fructus by hydrophilic interaction ultra high performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry.

    PubMed

    Zhou, Guisheng; Wang, Mengyue; Xu, Renjie; Li, Xiao-Bo

    2015-10-01

    A rapid and sensitive hydrophilic interaction ultra high performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry method was validated for the simultaneous determination of 20 nucleobases, nucleosides, and nucleotides (within 3.5 min), and then was employed to test the functional food of Luo-Han-Guo samples. The analysis showed that the Luo-Han-Guo was rich in guanosine and uridine, but contained trace levels of the other target compounds. Chemometrics methods were employed to identify 40 batches of Luo-Han-Guo samples from different cultivated forms, regions and varieties. Unsupervised hierarchical cluster analysis and principal component analysis were used to classify Luo-Han-Guo samples based on the level of the 20 target compounds, and the supervised learning method of counter propagation artificial neural network was utilized to further separate clusters and validate the established model. As a result, the samples could be clustered into three primary groups, in which correlation with cultivated varieties was observed. The present strategy could be applied to the investigation of other edible plants containing nucleobases, nucleosides, or nucleotides. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Table of nuclear electric quadrupole moments

    NASA Astrophysics Data System (ADS)

    Stone, N. J.

    2016-09-01

    This Table is a compilation of experimental measurements of static electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energy, half-life, spin and parity are given, along with a brief indication of the method and any reference standard used in the particular measurement. Experimental data from all quadrupole moment measurements actually provide a value of the product of the moment and the electric field gradient [EFG] acting at the nucleus. Knowledge of the EFG is thus necessary to extract the quadrupole moment. A single recommended moment value is given for each state, based, for each element, wherever possible, upon a standard reference moment for a nuclear state of that element studied in a situation in which the electric field gradient has been well calculated. For several elements one or more subsidiary EFG/moment reference is required and their use is specified. The literature search covers the period to mid-2015.

  2. Nuclear quadrupole resonance spectra database

    NASA Astrophysics Data System (ADS)

    Chihara, H.

    A computer-readable file of numerical data of nuclear quadrupole resonance frequency is being built which also serves as a bibliographic file. The data are compiled by reviewing original papers, reprints, and published data books and retrieving such data elements as substance names, nuclear mass number, temperature of measurements, resonance frequencies, nuclear quadrupole coupling constants, asymmetry parameters, and keywords. The database contains, if available, CAS registry number, molecular formulas and systematic names, and other synonyms of chemical substances. About 800 records have been loaded for online, TSS search through the Computer Center of Osaka University.

  3. Mixed radiation field dosimetry utilizing Nuclear Quadrupole Resonance

    SciTech Connect

    Hintenlang, D.

    1991-01-01

    This project has proposed to develop a novel dosimetry system that is capable of directly evaluating the chemical/biological damage caused by neutrons, photons, or both in a single measurement. The dosimeter itself will consist of a small volume of biological equivalent material that is probed for radiation damage with Nuclear Quadrupole Resonance (NQR) techniques. NQR has previously been utilized as a sensitive probe of structural and chemical changes at the molecular level for a variety of organic compounds. The biological equivalent materials used in this study will not only have a density similar to tissue (tissue equivalent) but will have the same atomic components as tissue. This is a significant requirement if the important neutron interactions that occur in tissue are to occur in the dosimeter as well. The overall objective of this study is to investigate a methodology to perform accurate mixed-field (neutron and photon) dosimetry for biological systems.

  4. Dynamics of a charged drop in a quadrupole electric field

    NASA Astrophysics Data System (ADS)

    Das, Sudip; Mayya, Y. S.; Thaokar, Rochish

    2015-07-01

    Quadrupole electric fields are commonly employed for confining charged conducting drops in Paul traps for studying Rayleigh instability characteristics. We investigate the effect of these fields on the deformation and stability characteristics of a charged liquid drop, using the axisymmetric boundary integral method (BIM). Different combinations of the amount of charge and strength of the electric field give rise to different equilibrium shapes. Interestingly, unlike in the case of uniform fields, stable oblate equilibrium drop shapes are sustained in quadrupole fields. In a positive endcap configuration of the quadrupole setup a drop carrying a small negative charge displays a transition from oblate to prolate as the field strength increases. On the other hand, for the case of a highly charged drop, a shift in the Rayleigh critical charge is observed in the presence of a weak quadrupole field. The Rayleigh instability displays imperfect transcritical bifurcation characteristics with respect to imposed prolate and oblate perturbations. Results are of significance in i) interpreting deformation and the Rayleigh stability effects using Paul traps with quadrupole fields, ii) designing more efficient quadrupole-field-based technologies for emulsification of water in oil.

  5. Nuclear Quadrupole Moments and Nuclear Shell Structure

    DOE R&D Accomplishments Database

    Townes, C. H.; Foley, H. M.; Low, W.

    1950-06-23

    Describes a simple model, based on nuclear shell considerations, which leads to the proper behavior of known nuclear quadrupole moments, although predictions of the magnitudes of some quadrupole moments are seriously in error.

  6. Accretion disks around a mass with quadrupole

    NASA Astrophysics Data System (ADS)

    Abishev, M.; Boshkayev, K.; Quevedo, H.; Toktarbay, S.

    We consider the stability properties of circular orbits of test particles moving around a mass with quadrupole. We show that the quadrupole modifies drastically the properties of an accretion disk made of such test particles.

  7. In silico and in vitro metabolism studies support identification of designer drugs in human urine by liquid chromatography/quadrupole-time-of-flight mass spectrometry.

    PubMed

    Tyrkkö, Elli; Pelander, Anna; Ketola, Raimo A; Ojanperä, Ilkka

    2013-08-01

    Human phase I metabolism of four designer drugs, 2-desoxypipradrol (2-DPMP), 3,4-dimethylmethcathinone (3,4-DMMC), α-pyrrolidinovalerophenone (α-PVP), and methiopropamine (MPA), was studied using in silico and in vitro metabolite prediction. The metabolites were identified in drug abusers’ urine samples using liquid chromatography/quadrupole-time-of-flight mass spectrometry (LC/Q-TOF/MS). The aim of the study was to evaluate the ability of the in silico and in vitro methods to generate the main urinary metabolites found in vivo. Meteor 14.0.0 software (Lhasa Limited) was used for in silico metabolite prediction, and in vitro metabolites were produced in human liver microsomes (HLMs). 2-DPMP was metabolized by hydroxylation, dehydrogenation, and oxidation, resulting in six phase I metabolites. Six metabolites were identified for 3,4-DMMC formed via N-demethylation, reduction, hydroxylation, and oxidation reactions. α-PVP was found to undergo reduction, hydroxylation, dehydrogenation, and oxidation reactions, as well as degradation of the pyrrolidine ring, and seven phase I metabolites were identified. For MPA, the nor-MPA metabolite was detected. Meteor software predicted the main human urinary phase I metabolites of 3,4-DMMC, α-PVP, and MPA and two of the four main metabolites of 2-DPMP. It assisted in the identification of the previously unreported metabolic reactions for α-PVP. Eight of the 12 most abundant in vivo phase I metabolites were detected in the in vitro HLM experiments. In vitro tests serve as material for exploitation of in silico data when an authentic urine sample is not available. In silico and in vitro designer drug metabolism studies with LC/Q-TOF/MS produced sufficient metabolic information to support identification of the parent compound in vivo.

  8. Multistage fragmentation of ion trap mass spectrometry system and pseudo-MS3 of triple quadrupole mass spectrometry characterize certain (E)-3-(dimethylamino)-1-arylprop-2-en-1-ones: a comparative study.

    PubMed

    Abdelhameed, Ali S; Kadi, Adnan A; Abdel-Aziz, Hatem A; Angawi, Rihab F; Attwa, Mohamed W; Al-Rashood, Khalid A

    2014-01-01

    A new approach was recently introduced to improve the structure elucidation power of tandem mass spectrometry simulating the MS(3) of ion trap mass spectrometry system overcoming the different drawbacks of the latter. The fact that collision induced dissociation in the triple quadrupole mass spectrometer system provides richer fragment ions compared to those achieved in the ion trap mass spectrometer system utilizing resonance excitation. Moreover, extracting comprehensive spectra in the ion trap needs multistage fragmentation, whereas similar fragment ions may be acquired from one stage product ion scan using the triple quadrupole mass spectrometer. The new strategy was proven to enhance the qualitative performance of tandem mass spectrometry for structural elucidation of different chemical entities. In the current study we are endeavoring to prove our hypothesis of the efficiency of the new pseudo-MS(3) technique via its comparison with the MS(3) mode of ion trap mass spectrometry system. Ten pharmacologically and synthetically important (E)-3-(dimethylamino)-1-arylprop-2-en-1-ones (enaminones 4a-j) were chosen as model compounds for this study. This strategy permitted rigorous identification of all fragment ions using triple quadrupole mass spectrometer with sufficient specificity. It can be used to elucidate structures of different unknown components. The data presented in this paper provide clear evidence that our new pseudo-MS(3) may simulate the MS(3) of ion trap spectrometry system.

  9. Removal of Axial Twist in RHIC Insertion Quadrupole Magnets

    NASA Astrophysics Data System (ADS)

    Cozzolino, J.; Anerella, M.; Jain, A.; Louie, W.; Muratore, P.

    1997-05-01

    The focusing triplets located on either side of the six interaction points of RHIC each consist of three 13cm aperture quadrupoles with magnetic lengths of 1.44m (Q1), 3.40m (Q2), and 2.10m (Q3). The field quality and alignment of these magnets are most critical to the performance of the accelerator. The maximum allowable axial twist of the cold mass, defined as the standard deviation in the quadrupole roll angle, is 0.5 mrad. This requirement has occasionally exceeded the capabilities of the assembly fixturing and the procedures used to complete the axial welding of the shell halves around the cold mass yoke. A corrective shell welding technique has been successfully employed to remove excessive axial twist of the 13cm quadrupoles. This ``custom straightening" method will be described along with the before and after mechanical inspection data. The magnetic results which confirm the untwisting procedure shall also be discussed.

  10. Effect of nuclear quadrupole moments on parity nonconservation in atoms

    NASA Astrophysics Data System (ADS)

    Flambaum, V. V.; Dzuba, V. A.; Harabati, C.

    2017-07-01

    Nuclei with spin I ≥1 have a weak quadrupole moment which leads to tensor contribution to the parity nonconserving interaction between nuclei and electrons. We calculate this contribution for atoms of current experiment interest Yb+, Fr, and Ra+. We have also performed order of magnitude estimates and found strong enhancement of the weak quadrupole effects due to the close levels of opposite parity in many lanthanoids (e.g., Nd, Gd, Dy, Ho, Er, Pr, Sm) and Ra. Another possibility is to measure the parity-nonconservation (PNC) transitions between the hyperfine components of the ground state of Bi. Since nuclear weak charge is dominated by neutrons this opens a way of measuring quadrupole moments of neutron distribution in nuclei.

  11. Quadrupole magnets for the SSC

    SciTech Connect

    Lietzke, A.; Barale, P.; Benjegerdes, R.; Caspi, S.; Cortella, J.; Dell`Orco, D.; Gilbert, W.; Green, M.I.; Mirk, K.; Peters, C.; Scanlan, R.; Taylor, C.E.; Wandesforde, A.

    1992-08-01

    At LBL, we have designed, constructed, and tested ten models (4-1meter, 6-5meter) of the Superconducting Super Collider (SSC) main-ring 5 meter focusing quadrupole magnet (211Tesla/meter). The results of this program are herein summarized.

  12. LCLS Undulator Quadrupole Fiducialization Plan

    SciTech Connect

    Wolf, Zachary; Levashov, Michael; Lundahl, Eric; Reese, Ed; LeCocq, Catherine; Ruland, Robert; /SLAC

    2010-11-24

    This note presents the fiducialization plan for the LCLS undulator quadrupoles. The note begins by summarizing the requirements for the fiducialization. A discussion of the measurement equipment is presented, followed by the methods used to perform the fiducialization and check the results. This is followed by the detailed fiducialization plan in which each step is enumerated. Finally, the measurement results and data storage formats are presented. The LCLS is made up of 33 assemblies consisting of an undulator, quadrupole, beam finder wire, and other components mounted on a girder. The components must be mounted in such a way that the beam passes down the axis of each component. In this note, we describe how the ideal beam axis is related to tooling balls on the quadrupole. This step, called fiducialization, is necessary because the ideal beam axis is determined magnetically, whereas tangible objects must be used to locate the quadrupole. The note begins with the list of fiducialization requirements. The laboratory in which the work will be performed and the relevant equipment is then briefly described. This is followed by a discussion of the methods used to perform the fiducialization and the methods used to check the results. A detailed fiducialization plan is presented in which all the steps of fiducialization are enumerated. A discussion of the resulting data files and directory structure concludes the note.

  13. Metabolomic study on the antihypertensive effect of S-1-propenylcysteine in spontaneously hypertensive rats using liquid chromatography coupled with quadrupole-Orbitrap mass spectrometry.

    PubMed

    Matsutomo, Toshiaki; Ushijima, Mitsuyasu; Kodera, Yukihiro; Nakamoto, Masashi; Takashima, Miyuki; Morihara, Naoaki; Tamura, Koichi

    2017-03-01

    Aged garlic extract (AGE) has been shown to improve hypertension in both clinical trials and experimental animal models. However, the active ingredient of AGE remains unknown. In the present study, we investigated the antihypertensive effects of AGE and its major constituents including S-1-propenylcysteine (S1PC) and S-allylcysteine (SAC) using spontaneously hypertensive rats (SHR) and found that S1PC is an active substance to lower blood pressure in SHR. In addition, the metabolomics approach was used to investigate the potential mechanism of the antihypertensive action of S1PC in SHR. Treatment with AGE (2g/kg body weight) or S1PC (6.5mg/kg body weight; equivalent to AGE 2g/kg body weight) significantly decreased the systolic blood pressure (SBP) of SHR after the repeated administration for 10 weeks, whereas treatment with SAC (7.9mg/kg body weight; equivalent to AGE 2g/kg body weight) did not decrease the SBP. After the treatment for 10 weeks, the plasma samples obtained from Wistar Kyoto (WKY) rats and SHR were analyzed by means of ultra high performance liquid chromatography coupled with high-resolution quadrupole-Orbitrap mass spectrometry. Multivariate statistical analysis of LC-MS data showed a clear difference in the metabolite profiles between WKY rats and SHR. The results indicated that 30 endogenous metabolites significantly contributed to the difference and 7 of 30 metabolites were changed by the S1PC treatment. Furthermore, regression analysis showed correlation between SBP and the plasma levels of betaine, tryptophan and 3 LysoPCs. This metabolomics approach suggested that S1PC could exert its antihypertensive effect by affecting glycine, serine and threonine metabolism, tryptophan metabolism and glycerophospholipid metabolism.

  14. Studies of food drug interactions.

    PubMed

    Aman, Syed Faisal; Hassan, Fouzia; Naqvi, Baqar S; Hasan, Syed Muhammmad Farid

    2010-07-01

    Medicines can treat and alleviate many diseases provided that they must be taken properly to ensure that they are safe and useful. One issue related with the medicines is that whether to take on empty stomach or with food. The present work gives information regarding food-drug interactions that were studied by collecting seventy five prescriptions from various hospitals. In most of the collected prescriptions, food-drug interactions were detected using the literature available. It was also found that only few studies have been carried out so far on the effect of food on drug disposition in the Asian population. Thus more studies on food-drug interactions particularly in the local population is recommended in order to determine the effect of food and food components on drug disposition and to the kinetics of the drugs which has not yet well highlighted in this part of the world.

  15. Vibration study of the APS storage ring 0.8 meter quadrupole magnet/magnet support assembly

    SciTech Connect

    Jendrzejczyk, J.A.; Wambsganss, M.W.; Smith, R.K.

    1991-06-01

    The objectives of this study are as follows: Determine the vibration characteristics (frequency, damping, and mode shapes) of the magnet on prototypic supports (the actual mounting system used to mount the magnet on the girder). Measure system response to ambient floor motion. Measure the effect of various modifications to determine if the magnet response can be modified to minimize unwanted response characteristics. Modifications investigated include support schemes, increasing system damping, and increasing mechanical rigidity. Measure system response to coolant flow. Determine vibrational characteristics of a large concrete block placed on a concrete floor, including response to ambient floor motions.

  16. Trapping of Electron Cloud LLC/Cesrta Quadrupole and Sextupole Magnets

    SciTech Connect

    Wang, L; Pivi, M.; /SLAC

    2011-08-18

    The Cornell Electron Storage Ring (CESR) has been reconfigured as an ultra low emittance damping ring for use as a test accelerator (CesrTA) for International Linear Collider (ILC) damping ring R&D [1]. One of the primary goals of the CesrTA program is to investigate the interaction of the electron cloud with low emittance positron beam to explore methods to suppress the electron cloud, develop suitable advanced instrumentation required for these experimental studies and benchmark predictions by simulation codes. This paper reports the simulation of the electron-cloud formation in CESRTA and ILC quadrupole and sextupole magnets using the 3D code CLOUDLAND. We found that electrons can be trapped with a long lifetime in a quadrupole and sextupole magnet due to the mirror field trapping mechanism. We study the effects of magnet strength, bunch current, ante-chamber effect, bunch spacing effect and secondary emission yield (SEY) in great detail. The development of an electron cloud in magnets is the main concern where a weak solenoid field is not effective. Quadrupole and sextupole magnets have mirror field configurations which may trap electrons by the mirror field trapping mechanism [2]. Fig.1 shows the orbit of a trapped electron in a quadrupole magnet. The electron makes gyration motion (called transverse motion) and also moves along the field line (called longitudinal motion). At the mirror point (middle of the field line), there is a maximum longitudinal energy and minimum transverse energy. When the electron moves away from the mirror point, its longitudinal energy reduces and the transverse energy increases as the magnetic field increases. If the magnetic field is strong enough, the longitudinal energy becomes zero at one point and then the electron is turned back by the strong field. Note that the electrons are trapped in the region near the middle of the field lines. Although all quadrupole and sextupole magnets can trap electrons in principle, the trapping

  17. Manometer extension for high pressure measurement: Nuclear quadrupole resonance study of Cu{sub 2}O with a modified Bridgman anvil cell up to 10 GPa

    SciTech Connect

    Fukazawa, H.; Yamatoji, N.; Kohori, Y.; Terakura, C.; Takeshita, N.; Tokura, Y.; Takagi, H.

    2007-01-15

    We report {sup 63}Cu nuclear quadrupole resonance (NQR) measurement of Cu{sub 2}O under pressure up to about 10 GPa at low temperatures. Because the lattice parameter of Cu{sub 2}O changes with increasing pressure, the electric field gradient at the Cu site also changes correspondingly with pressure. This enables us to use the Cu{sub 2}O as an in situ manometer for high pressure nuclear magnetic resonance/NQR up to about 9 GPa.

  18. Electric Quadrupole Transitions in the a1Δg←X3Σ-g Band of Oxygen: a Case Study

    NASA Astrophysics Data System (ADS)

    Gordon, I. E.; Kassi, S.; Campargue, A.; Toon, G. C.

    2010-06-01

    Electric quadrupole transitions in the a1Δg←X3Σ-g band of 16O2 are reported for the first time. They were first detected in atmospheric solar spectra acquired with a ground based Fourier transform spectrometer (FTS) in Park Falls, WI. Subsequently high-sensitivity Continuous Wave-Cavity Ring Down Spectroscopy (CW-CRDS) experiments were carried out at Grenoble University in the 7717-7917 cm-1 region in order to provide quantitative intensity information for these transitions. Experimental intensities of the ΔJ=±2 transition were used as input data for calculation of the complete list of electric quadrupole transitions with ΔJ=±2, ±1 and 0. The calculation was carried out for the intermediate coupling case and assuming that these transitions are possible only through mixing of the Ω=0 component of the ground electronic state and b1Σ+g state induced by spin-orbit coupling. The calculated line list agrees well with experimental measurements and was used to improve the residuals of the fitted atmospheric spectrum. Emission probability for the electric quadrupole band was determined to be (1.02±0.10)×10-6 s-1.

  19. ANALYTICAL SOLUTIONS OF SINGULAR ISOTHERMAL QUADRUPOLE LENS

    SciTech Connect

    Chu Zhe; Lin, W. P.; Yang Xiaofeng E-mail: linwp@shao.ac.cn

    2013-06-20

    Using an analytical method, we study the singular isothermal quadrupole (SIQ) lens system, which is the simplest lens model that can produce four images. In this case, the radial mass distribution is in accord with the profile of the singular isothermal sphere lens, and the tangential distribution is given by adding a quadrupole on the monopole component. The basic properties of the SIQ lens have been studied in this Letter, including the deflection potential, deflection angle, magnification, critical curve, caustic, pseudo-caustic, and transition locus. Analytical solutions of the image positions and magnifications for the source on axes are derived. We find that naked cusps will appear when the relative intensity k of quadrupole to monopole is larger than 0.6. According to the magnification invariant theory of the SIQ lens, the sum of the signed magnifications of the four images should be equal to unity, as found by Dalal. However, if a source lies in the naked cusp, the summed magnification of the left three images is smaller than the invariant 1. With this simple lens system, we study the situations where a point source infinitely approaches a cusp or a fold. The sum of the magnifications of the cusp image triplet is usually not equal to 0, and it is usually positive for major cusps while negative for minor cusps. Similarly, the sum of magnifications of the fold image pair is usually not equal to 0 either. Nevertheless, the cusp and fold relations are still equal to 0 in that the sum values are divided by infinite absolute magnifications by definition.

  20. Larp Nb3Sn Quadrupole Magnets for the Lhc Luminosity Upgrade

    NASA Astrophysics Data System (ADS)

    Ferracin, P.

    2010-04-01

    The US LHC Accelerator Research Program (LARP) is a collaboration between four US laboratories (BNL, FNAL, LBNL, and SLAC) aimed at contributing to the commissioning and operation of the LHC and conducting R&D on its luminosity upgrade. Within LARP, the Magnet Program's main goal is to demonstrate that Nb3Sn superconducting magnets are a viable option for a future upgrade of the LHC Interaction Regions. Over the past four years, LARP has successfully fabricated and tested several R&D magnets: 1) the subscale quadrupole magnet SQ, to perform technology studies with 300 mm long racetrack coils, 2) the technology quadrupole TQ, to investigate support structure behavior with 1 m long cos 2θ coils, and 3) the long racetrack magnet LR, to test 3.6 m long racetrack coils. The next milestone consists in the fabrication and test of the 3.7 m long quadrupole magnet LQ, with the goal of demonstrating that Nb3Sn technology is mature for use in high energy accelerators. After an overview of design features and test result of the LARP magnets fabricated so far, this paper focuses on the status of the fabrication of LQ: we describe the production of the 3.4 m long cos 2θ coils, and the of the qualification support structure. Finally, the status of the development of the next 1 m long model HQ, conceived to explore stress and field limits of Nb3Sn superconducting, magnets, is presented.

  1. Rovibrational matrix elements of the quadrupole moment of N2 in a solid parahydrogen matrix

    NASA Astrophysics Data System (ADS)

    Mishra, Adya P.; Balasubramanian, T. K.

    2008-11-01

    The present work pertains to the study of the rotational dynamics of N2 molecules solvated in a matrix of solid para-H2. It is shown that the mixing of the rotational states due to the anisotropic part of the N2-H2 pair potential in the solid gives rise to an additional 5.4% contribution to the intensity of quadrupole-induced double transitions involving N2-H2 pair. Hence the recently reported quadrupole moment matrix element of N2 in a solid para-H2 crystal [A. P. Mishra and T. K. Balasubramanian, J. Chem. Phys. 125, 124507 (2006)], which was deduced from a comparison of the theoretical intensity (with rotational mixing of states neglected) with the measured value is larger by ˜2.7%. The ground electronic state rovibrational matrix elements ⟨v'J'|Q2(r)|vJ⟩ of N2 molecule in a solid parahydrogen matrix for v,v'≤1 and J,J'≤4 have also been computed by taking into account the changes in the intramolecular potential of N2 due to the intermolecular interaction in the matrix. The computed quadrupole moment matrix elements agree well with a few available values (for v =v'=0) deduced from the observed transitions.

  2. Urinary metabonomic study of Panax ginseng in deficiency of vital energy rat using ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

    PubMed

    Lin, He; Pi, Zifeng; Men, Lihui; Chen, Weijia; Liu, Zhiqiang; Liu, Zhongying

    2016-05-26

    Deficiency of vital energy (DE) is called Qi-deficiency, a traditional Chinese medicine syndrome. It is an indicator of a disease emerging though fuzzy, dynamic, complex, nonspecific and subjective. Ginseng is regarded as the king of herbs. It is famous for the function of replenishing qi in traditional Chinese medicine. It has treatment potential for DE caused by various reasons. This study aimed to investigate the mechanism of ginseng treating symptom DE with the method of metabolomics. Thirty-five rats were randomly divided into three groups: normal control group, DE model group and ginseng treatment group. The DE model rats were administered daily with ginseng decoctiondecoctiondecoction intragastrically and others with water for 15 days. Urine was analyzed with ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Principal component analysis (PCA) and orthogonal projection to latent structures squares-discriminant analysis (OPLS-DA) were built to distinguish the three groups in this study and find potential biomarkers. The three groups are clearly separated and find out their metabolic distinction in PCA score plots. It showed that the metabolic profile of ginseng treatment group was changed to normal control group after administration of ginseng. Fifteen potential biomarkers are identified by OPLS-DA including Xanthurenic acid, kynurenic acid, Pantothenic acid, which are chiefly involved in tryptophan metabolism, taurine and hypotaurine metabolism, citric acid cycle, bile acid biosynthesis, alpha linolenic acid and linoleic acid metabolism. These biomarkers and the networks of their corresponding pathways will help to explain the mechanism of DE and ginseng treatment. The results of blood biochemical indicators routine and urinary metabonomic reveal that ginseng have good abilities to regulate the energy metabolism, immune function and antioxidant activities. And UPLC-Q-TOF-MS-based metabolomics can

  3. Higher order parametric excitation modes for spaceborne quadrupole mass spectrometers

    SciTech Connect

    Gershman, D. J.; Block, B. P.; Rubin, M.; Zurbuchen, T. H.; Benna, M.; Mahaffy, P. R.

    2011-12-15

    This paper describes a technique to significantly improve upon the mass peak shape and mass resolution of spaceborne quadrupole mass spectrometers (QMSs) through higher order auxiliary excitation of the quadrupole field. Using a novel multiresonant tank circuit, additional frequency components can be used to drive modulating voltages on the quadrupole rods in a practical manner, suitable for both improved commercial applications and spaceflight instruments. Auxiliary excitation at frequencies near twice that of the fundamental quadrupole RF frequency provides the advantages of previously studied parametric excitation techniques, but with the added benefit of increased sensed excitation amplitude dynamic range and the ability to operate voltage scan lines through the center of upper stability islands. Using a field programmable gate array, the amplitudes and frequencies of all QMS signals are digitally generated and managed, providing a robust and stable voltage control system. These techniques are experimentally verified through an interface with a commercial Pfeiffer QMG422 quadrupole rod system. When operating through the center of a stability island formed from higher order auxiliary excitation, approximately 50% and 400% improvements in 1% mass resolution and peak stability were measured, respectively, when compared with traditional QMS operation. Although tested with a circular rod system, the presented techniques have the potential to improve the performance of both circular and hyperbolic rod geometry QMS sensors.

  4. Higher order parametric excitation modes for spaceborne quadrupole mass spectrometers

    NASA Astrophysics Data System (ADS)

    Gershman, D. J.; Block, B. P.; Rubin, M.; Benna, M.; Mahaffy, P. R.; Zurbuchen, T. H.

    2011-12-01

    This paper describes a technique to significantly improve upon the mass peak shape and mass resolution of spaceborne quadrupole mass spectrometers (QMSs) through higher order auxiliary excitation of the quadrupole field. Using a novel multiresonant tank circuit, additional frequency components can be used to drive modulating voltages on the quadrupole rods in a practical manner, suitable for both improved commercial applications and spaceflight instruments. Auxiliary excitation at frequencies near twice that of the fundamental quadrupole RF frequency provides the advantages of previously studied parametric excitation techniques, but with the added benefit of increased sensed excitation amplitude dynamic range and the ability to operate voltage scan lines through the center of upper stability islands. Using a field programmable gate array, the amplitudes and frequencies of all QMS signals are digitally generated and managed, providing a robust and stable voltage control system. These techniques are experimentally verified through an interface with a commercial Pfeiffer QMG422 quadrupole rod system. When operating through the center of a stability island formed from higher order auxiliary excitation, approximately 50% and 400% improvements in 1% mass resolution and peak stability were measured, respectively, when compared with traditional QMS operation. Although tested with a circular rod system, the presented techniques have the potential to improve the performance of both circular and hyperbolic rod geometry QMS sensors.

  5. Quadrupole contribution to the third-order optical activity spectroscopy

    NASA Astrophysics Data System (ADS)

    Choi, Jun-Ho; Cho, Minhaeng

    2007-07-01

    Time-resolved nonlinear optical activity measurement spectroscopy can be a useful tool for studying biomolecular and chemical reaction dynamics of chiral molecules. Only recently, the two-dimensional (2D) circularly polarized photon echo (CP-PE) spectroscopy of polypeptides and a photosynthetic light-harvesting complex were discussed, where the beam configuration was specifically controlled in such a way to eliminate the quadrupole contribution to the CP-PE signal. In this paper, we generalize the CP-PE spectroscopy by including the transition quadrupole contributions from peptide amide I vibrational transition and chlorophyll electronic transition. By using a density functional theory calculation method, the corresponding amide I vibrational and chlorophyll Qy electronic transition quadrupole tensor elements are determined. Amplitude of nonlinear optical transition pathway involving a quadrupole transition is found to be comparable to those of magnetic dipole terms for two different cases considered, i.e., dipeptides and photosynthetic antenna complex. However, due to the rotational averaging factors, the overall quadrupole contribution is an order of magnitude smaller than the magnetic dipole contribution. This suggests that the conventional 2D photon echo method and experimental scheme can be directly used to measure the 2D CP-PE signal from proteins and molecular complexes and that the 2D CP-PE signal is mainly dictated by the magnetic dipole contribution.

  6. Quadrupole contribution to the third-order optical activity spectroscopy.

    PubMed

    Choi, Jun-Ho; Cho, Minhaeng

    2007-07-14

    Time-resolved nonlinear optical activity measurement spectroscopy can be a useful tool for studying biomolecular and chemical reaction dynamics of chiral molecules. Only recently, the two-dimensional (2D) circularly polarized photon echo (CP-PE) spectroscopy of polypeptides and a photosynthetic light-harvesting complex were discussed, where the beam configuration was specifically controlled in such a way to eliminate the quadrupole contribution to the CP-PE signal. In this paper, we generalize the CP-PE spectroscopy by including the transition quadrupole contributions from peptide amide I vibrational transition and chlorophyll electronic transition. By using a density functional theory calculation method, the corresponding amide I vibrational and chlorophyll Q(y) electronic transition quadrupole tensor elements are determined. Amplitude of nonlinear optical transition pathway involving a quadrupole transition is found to be comparable to those of magnetic dipole terms for two different cases considered, i.e., dipeptides and photosynthetic antenna complex. However, due to the rotational averaging factors, the overall quadrupole contribution is an order of magnitude smaller than the magnetic dipole contribution. This suggests that the conventional 2D photon echo method and experimental scheme can be directly used to measure the 2D CP-PE signal from proteins and molecular complexes and that the 2D CP-PE signal is mainly dictated by the magnetic dipole contribution.

  7. Extraterrestrial Studies Using Nuclear Interactions

    NASA Technical Reports Server (NTRS)

    Reedy, Robert C.

    2003-01-01

    Cosmogenic nuclides were used to study the recent histories of the aubrite Norton County and the pallasite Brenham using calculated production rates. Calculations were done of the rates for making cosmogenic noble-gas isotopes in the Jovian satellite Europa by the interactions of galactic cosmic rays and especially trapped Jovian protons. Cross sections for the production of cosmogenic nuclides were reported and plans made to measure additional cross sections. A new code, MCNPX, was used to numerically simulate the interactions of cosmic rays with matter and the subsequent production of cosmogenic nuclides. A review was written about studies of extraterrestrial matter using cosmogenic radionuclides. Several other projects were done. Results are reviewed here with references to my recent publications for details.

  8. IRAS study of interacting galaxies

    NASA Astrophysics Data System (ADS)

    Allam, S.

    1998-04-01

    Interacting galaxies are ideal laboratories for studying the influence of gravitational forces on galaxies. From theoretical and observational studies, we know how sensitive galaxies are to tidal interaction, from the formation of tidal tails, bridges, bursts of star formation up to a complete merging of the galaxies. The Far Infrared (FIR) properties of interacting galaxies give information on the dynamical and physical properties of these systems. Several earlier studies using the IRAS point source catalogue (IPSC) and IRAS Faint Source Survey (FSS), showed that the FIR emission from interacting/merging galaxies is enhanced with respect to isolated non-interacting galaxies; moreover, that high density environments have more influence in producing enhanced FIR emission over isolated interacting systems. In general the ratio of FIR to optical luminosity in interacting systems was found to be enhanced. It is regarded as an increased star formation (SF) rate in these systems. Later on, due to the rather high IPSC detection threshold, and its low resolution, several contradictory results have been reported. In this thesis the FIR emission from interacting galaxies is studied by using the high resolution IRAS software introduced by Bontekoe et al. (1994). This soft ware package uses a Maximum Entropy method (hereafter MaxEnt). The MaxEnt formulation is rooted in Bayesian probability theory. The raw IRAS data contains the Point Spread Function (PSF) of both the telescope mirror (60 cm --> 1 arcmin at 60 μm) and the PSF of the detectors (≃ 5 arcmin). Since there is much redundancy in the data, the MaxEnt routine can be used to remove the 5 arcmin PSF from the detectors. For many interacting galaxies this is enough to resolve them. The size of the images was chosen such that the objects could be studied including their surroundings. The absolute position calibration and flux estimates for the MaxEnt images are described in Allam et al. (1996). Because of the high

  9. The use of the pairing-quadrupole connections in PQM for application in nuclear systems

    NASA Astrophysics Data System (ADS)

    Drumev, K. P.; Georgieva, A. I.

    2016-03-01

    Within the algebraic realization of the Pairing-plus-Quadrupole Model /PQM/ in the framework of the Elliott's SU(3) Model,we present some particular applications for realistic nuclear systems. The probability distribution of the SU(3) basis states within the isovector, isoscalar and total pairing eigenstates is obtained through a numerical diagonalization of the PQM Hamiltonian in each limit. This allows the investigation of the interplay between the pairing and quadrupole interactions in the Hamiltonian of the PQM, containing all of them as limiting cases. The relative strengths of the dynamically symmetric quadrupole-quadrupole interaction with the considered types of pairing interactions are investigated systematically for systems like the 20Ne.

  10. Stability of an aqueous quadrupole micro-trap

    DOE PAGES

    Park, Jae Hyun; Krstić, Predrag S.

    2012-01-01

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

  11. Stability of an aqueous quadrupole micro-trap

    SciTech Connect

    Park, Jae Hyun; Krstić, Predrag S.

    2012-01-01

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

  12. LARP Long Quadrupole: A "Long" Step Toward an LHC

    ScienceCinema

    Giorgio Ambrosio

    2016-07-12

    The beginning of the development of Nb3Sn magnets for particle accelerators goes back to the 1960’s. But only very recently has this development begun to face the challenges of fabricating Nb3Sn magnets which can meet the requirements of modern particle accelerators. LARP (the LHC Accelerator Research Program) is leading this effort focusing on long models of the Interaction Region quadrupoles for a possible luminosity upgrade of the Large Hadron Collider. A major milestone in this development is to test, by the end of 2009, 4m-long quadrupole models, which will be the first Nb3Sn accelerator-type magnets approaching the length of real accelerator magnets. The Long Quadrupoles (LQ) are “Proof-of-Principle” magnets which are to demonstrate that Nb3Sn technology is sufficiently mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, under development at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. Several challenges must be addressed for the successful fabrication of long Nb3Sn coils and magnets. These challenges and the solutions adopted will be presented together with the main features of the LQ magnets. Several R&D lines are participating to this effort and their contributions will be also presented.

  13. LARP Long Quadrupole: A "Long" Step Toward an LHC

    SciTech Connect

    Giorgio Ambrosio

    2008-02-13

    The beginning of the development of Nb3Sn magnets for particle accelerators goes back to the 1960’s. But only very recently has this development begun to face the challenges of fabricating Nb3Sn magnets which can meet the requirements of modern particle accelerators. LARP (the LHC Accelerator Research Program) is leading this effort focusing on long models of the Interaction Region quadrupoles for a possible luminosity upgrade of the Large Hadron Collider. A major milestone in this development is to test, by the end of 2009, 4m-long quadrupole models, which will be the first Nb3Sn accelerator-type magnets approaching the length of real accelerator magnets. The Long Quadrupoles (LQ) are “Proof-of-Principle” magnets which are to demonstrate that Nb3Sn technology is sufficiently mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, under development at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. Several challenges must be addressed for the successful fabrication of long Nb3Sn coils and magnets. These challenges and the solutions adopted will be presented together with the main features of the LQ magnets. Several R&D lines are participating to this effort and their contributions will be also presented.

  14. An introduction to quadrupole-time-of-flight mass spectrometry.

    PubMed

    Chernushevich, I V; Loboda, A V; Thomson, B A

    2001-08-01

    A brief introduction is presented to the basic principles and application of a quadrupole-time-of-flight (TOF) tandem mass spectrometer. The main features of reflecting TOF instruments with orthogonal injection of ions are discussed. Their operation and performance are compared with those of triple quadrupoles with electrospray ionization and matrix-assisted laser desorption/ionization (MALDI) TOF mass spectrometers. Examples and recommendations are provided for all major operational modes: mass spectrometry (MS) and tandem MS (MS/MS), precursor ion scans and studies of non-covalent complexes. Basic algorithms for liquid chromatography/MS/MS automation are discussed and illustrated by two applications.

  15. Simultaneous quadrupole and octupole shape phase transitions in Thorium

    NASA Astrophysics Data System (ADS)

    Li, Z. P.; Song, B. Y.; Yao, J. M.; Vretenar, D.; Meng, J.

    2013-11-01

    The evolution of quadrupole and octupole shapes in Th isotopes is studied in the framework of nuclear Density Functional Theory. Constrained energy maps and observables calculated with microscopic collective Hamiltonians indicate the occurrence of a simultaneous quantum shape phase transition between spherical and quadrupole-deformed prolate shapes, and between non-octupole and octupole-deformed shapes, as functions of the neutron number. The nucleus 224Th is closest to the critical point of a double phase transition. A microscopic mechanism of this phenomenon is discussed in terms of the evolution of single-nucleon orbitals with deformation.

  16. Low-frequency quadrupole impedance of undulators and wigglers

    NASA Astrophysics Data System (ADS)

    Blednykh, A.; Bassi, G.; Hidaka, Y.; Smaluk, V.; Stupakov, G.

    2016-10-01

    An analytical expression of the low-frequency quadrupole impedance for undulators and wigglers is derived and benchmarked against beam-based impedance measurements done at the 3 GeV NSLS-II storage ring. The adopted theoretical model, valid for an arbitrary number of electromagnetic layers with parallel geometry, allows to calculate the quadrupole impedance for arbitrary values of the magnetic permeability μr . In the comparison of the analytical results with the measurements for variable magnet gaps, two limit cases of the permeability have been studied: the case of perfect magnets (μr→∞ ), and the case in which the magnets are fully saturated (μr=1 ).

  17. First Test Results of the 150 mm Aperture IR Quadrupole Models for the High Luminosity LHC

    SciTech Connect

    Ambrosio, G.; Chlachidze, G.; Wanderer, P.; Ferracin, P.; Sabbi, G.

    2016-10-06

    The High Luminosity upgrade of the LHC at CERN will use large aperture (150 mm) quadrupole magnets to focus the beams at the interaction points. The high field in the coils requires Nb3Sn superconductor technology, which has been brought to maturity by the LHC Accelerator Re-search Program (LARP) over the last 10 years. The key design targets for the new IR quadrupoles were established in 2012, and fabrication of model magnets started in 2014. This paper discusses the results from the first single short coil test and from the first short quadrupole model test. Remaining challenges and plans to address them are also presented and discussed.

  18. Quadrupole Collectivity beyond N=28: Intermediate-Energy Coulomb Excitation of Ar47,48

    NASA Astrophysics Data System (ADS)

    Winkler, R.; Gade, A.; Baugher, T.; Bazin, D.; Brown, B. A.; Glasmacher, T.; Grinyer, G. F.; Meharchand, R.; McDaniel, S.; Ratkiewicz, A.; Weisshaar, D.

    2012-05-01

    We report on the first experimental study of quadrupole collectivity in the very neutron-rich nuclei Ar47,48 using intermediate-energy Coulomb excitation. These nuclei are located along the path from doubly magic Ca to collective S and Si isotopes, a critical region of shell evolution and structural change. The deduced B(E2) transition strengths are confronted with large-scale shell-model calculations in the sdpf shell using the state-of-the-art SDPF-Uand EPQQM effective interactions. The comparison between experiment and theory indicates that a shell-model description of Ar isotopes around N=28 remains a challenge.

  19. Quadrupole collectivity beyond N = 28: intermediate-energy Coulomb excitation of (47,48)Ar.

    PubMed

    Winkler, R; Gade, A; Baugher, T; Bazin, D; Brown, B A; Glasmacher, T; Grinyer, G F; Meharchand, R; McDaniel, S; Ratkiewicz, A; Weisshaar, D

    2012-05-04

    We report on the first experimental study of quadrupole collectivity in the very neutron-rich nuclei (47,48)Ar using intermediate-energy Coulomb excitation. These nuclei are located along the path from doubly magic Ca to collective S and Si isotopes, a critical region of shell evolution and structural change. The deduced B(E2) transition strengths are confronted with large-scale shell-model calculations in the sdpf shell using the state-of-the-art SDPF-Uand EPQQM effective interactions. The comparison between experiment and theory indicates that a shell-model description of Ar isotopes around N=28 remains a challenge.

  20. Water-module interaction studies

    NASA Technical Reports Server (NTRS)

    Mon, G.; Wen, L.; Ross, R., Jr.

    1988-01-01

    Mechanisms by which moisture enters photovoltaic modules and techniques for reducing such interactions are reported. Results from a study of the effectiveness of various module sealants are given. Techniques for measuring the rate and quantity of moisture ingress are discussed. It is shown that scribe lines and porous frit bridging conductors provide preferential paths for moisture ingress and that moisture diffusion by surface/interfacial paths is considerably more rapid than diffusion by bulk paths, which implies that thin-film substrate and supersubstrate modules are much more vulnerable to moist environments than are bulk-encapsulated crystalline-silicon modules. Design approaches that reduce moisture entry are discussed.

  1. Magnetic quench antenna for MQXF quadrupoles

    DOE PAGES

    Marchevsky, Maxim; Sabbi, GianLuca; Prestemon, Soren; ...

    2016-12-21

    High-field MQXF-series quadrupoles are presently under development by LARP and CERN for the upcoming LHC luminosity upgrade. Quench training and protection studies on MQXF prototypes require a capability to accurately localize quenches and measure their propagation velocity in the magnet coils. The voltage tap technique commonly used for such purposes is not a convenient option for the 4.2-m-long MQXF-A prototype, nor can it be implemented in the production model. We have developed and tested a modular inductive magnetic antenna for quench localization. The base element of our quench antenna is a round-shaped printed circuit board containing two orthogonal pairs ofmore » flat coils integrated with low-noise preamplifiers. The elements are aligned axially and spaced equidistantly in 8-element sections using a supporting rod structure. The sections are installed in the warm bore of the magnet, and can be stacked together to adapt for the magnet length. We discuss the design, operational characteristics and preliminary qualification of the antenna. Lastly, axial quench localization capability with an accuracy of better than 2 cm has been validated during training test campaign of the MQXF-S1 quadrupole.« less

  2. Magnetic quench antenna for MQXF quadrupoles

    SciTech Connect

    Marchevsky, Maxim; Sabbi, GianLuca; Prestemon, Soren; Strauss, Thomas; Stoynev, Stoyan; Chlachidze, Guram

    2016-12-21

    High-field MQXF-series quadrupoles are presently under development by LARP and CERN for the upcoming LHC luminosity upgrade. Quench training and protection studies on MQXF prototypes require a capability to accurately localize quenches and measure their propagation velocity in the magnet coils. The voltage tap technique commonly used for such purposes is not a convenient option for the 4.2-m-long MQXF-A prototype, nor can it be implemented in the production model. We have developed and tested a modular inductive magnetic antenna for quench localization. The base element of our quench antenna is a round-shaped printed circuit board containing two orthogonal pairs of flat coils integrated with low-noise preamplifiers. The elements are aligned axially and spaced equidistantly in 8-element sections using a supporting rod structure. The sections are installed in the warm bore of the magnet, and can be stacked together to adapt for the magnet length. We discuss the design, operational characteristics and preliminary qualification of the antenna. Lastly, axial quench localization capability with an accuracy of better than 2 cm has been validated during training test campaign of the MQXF-S1 quadrupole.

  3. Nuclear magnetic and nuclear quadrupole resonance parameters of β-carboline derivatives calculated using density functional theory

    NASA Astrophysics Data System (ADS)

    Ahmadinejad, Neda; Tari, Mostafa Talebi

    2017-04-01

    A density functional theory (DFT) calculations using B3LYP/6-311++G( d,p) method were carried out to investigate the relative stability of the molecules of β-carboline derivatives such as harmaline, harmine, harmalol, harmane and norharmane. Calculated nuclear quadrupole resonance (NQR) parameters were used to determine the 14N nuclear quadrupole coupling constant χ, asymmetry parameter η and EFG tensor ( q zz ). For better understanding of the electronic structure of β-carboline derivatives, natural bond orbital (NBO) analysis, isotropic and anisotropic NMR chemical shieldings were calculated for 14N nuclei using GIAO method for the optimized structures. The NBO analysis shows that pyrrole ring nitrogen (N9) atom has greater tendency than pyridine ring nitrogen (N2) atom to participate in resonance interactions and aromaticity development in the all of these structures. The NMR and NQR parameters were studied in order to find the correlations between electronic structure and the structural stability of the studied molecules.

  4. A Vibrating Wire System For Quadrupole Fiducialization

    SciTech Connect

    Wolf, Zachary

    2010-12-13

    A vibrating wire system is being developed to fiducialize the quadrupoles between undulator segments in the LCLS. This note provides a detailed analysis of the system. The LCLS will have quadrupoles between the undulator segments to keep the electron beam focused. If the quadrupoles are not centered on the beam axis, the beam will receive transverse kicks, causing it to deviate from the undulator axis. Beam based alignment will be used to move the quadrupoles onto a straight line, but an initial, conventional alignment must place the quadrupole centers on a straight line to 100 {micro}m. In the fiducialization step of the initial alignment, the position of the center of the quadrupole is measured relative to tooling balls on the outside of the quadrupole. The alignment crews then use the tooling balls to place the magnet in the tunnel. The required error on the location of the quadrupole center relative to the tooling balls must be less than 25 {micro}m. In this note, we analyze a system under construction for the quadrupole fiducialization. The system uses the vibrating wire technique to position a wire onto the quadrupole magnetic axis. The wire position is then related to tooling balls using wire position detectors. The tooling balls on the wire position detectors are finally related to tooling balls on the quadrupole to perform the fiducialization. The total 25 {micro}m fiducialization error must be divided between these three steps. The wire must be positioned onto the quadrupole magnetic axis to within 10 {micro}m, the wire position must be measured relative to tooling balls on the wire position detectors to within 15 {micro}m, and tooling balls on the wire position detectors must be related to tooling balls on the quadrupole to within 10 {micro}m. The techniques used in these three steps will be discussed. The note begins by discussing various quadrupole fiducialization techniques used in the past and discusses why the vibrating wire technique is our method

  5. MEASURING LOCAL GRADIENT AND SKEW QUADRUPOLE ERRORS IN RHIC IRS.

    SciTech Connect

    CARDONA,J.; PEGGS,S.; PILAT,R.; PTITSYN,V.

    2004-07-05

    The measurement of local linear errors at RHIC interaction regions using an ''action and phase'' analysis of difference orbits has already been presented. This paper evaluates the accuracy of this technique using difference orbits that were taken when known gradient errors and skew quadrupole errors were intentionally introduced. It also presents action and phase analysis of simulated orbits when controlled errors are intentionally placed in a RHIC simulation model.

  6. Spontaneous structural distortion of the metallic Shastry-Sutherland system Dy B4 by quadrupole-spin-lattice coupling

    NASA Astrophysics Data System (ADS)

    Sim, Hasung; Lee, Seongsu; Hong, Kun-Pyo; Jeong, Jaehong; Zhang, J. R.; Kamiyama, T.; Adroja, D. T.; Murray, C. A.; Thompson, S. P.; Iga, F.; Ji, S.; Khomskii, D.; Park, Je-Geun

    2016-11-01

    Dy B4 has a two-dimensional Shastry-Sutherland (Sh-S) lattice with strong Ising character of the Dy ions. Despite the intrinsic frustrations, it undergoes two successive transitions: a magnetic ordering at TN=20 K and a quadrupole ordering at TQ=12.5 K . From high-resolution neutron and synchrotron x-ray powder diffraction studies, we have obtained full structural information on this material in all phases and demonstrate that structural modifications occurring at quadrupolar transition lead to the lifting of frustrations inherent in the Sh-S model. Our paper thus provides a complete experimental picture of how the intrinsic frustration of the Sh-S lattice can be lifted by the coupling to quadrupole moments. We show that two other factors, i.e., strong spin-orbit coupling and long-range Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in metallic Dy B4 , play an important role in this behavior.

  7. Support Structure Design of the $$\\hbox{Nb}_{3}\\hbox{Sn}$$ Quadrupole for the High Luminosity LHC

    DOE PAGES

    Juchno, M.; Ambrosio, G.; Anerella, M.; ...

    2014-10-31

    New low-β quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb₃Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of themore » detailed 3D numerical analysis performed in preparation for the first short model test.« less

  8. Fast Fourier Transform Chlorine Nuclear Quadrupole Resonance Spectroscopy.

    NASA Astrophysics Data System (ADS)

    D'Iorio, Marie

    A nuclear quadrupole resonance spectrometer operating in the frequency range 1-40 MHz was updated for fast Fourier transform spectroscopy and coupled to a Nicolet 1180 computer and data acquisition system. It was used with a low temperature cryostat for studies shown down to liquid helium temperature and with a high pressure/low temperature system for studies down to liquid nitrogen temperature and up to six kilobars. The study of the ('35)Cl NQR spectrum of K(,2)OsCl(,6) at 298 K and 77 K revealed the presence of a satellite associated with the nearest neighbour chlorines to H('+) ion impurities located at vacant octahedral sties. This result is in agreement with the predictions of a point charge model calculation. A residence time for the H('+) ion was deduced and is consistent with the result obtained from dielectric measurements. A detailed study of the ('35)Cl NQR frequency in K(,2)ReCl(,6) was performed in the temperature range 85 - 130K where two structural phase transitions occur, and at pressures from 1 to 2643 bars. A number of unusual features were revealed and discussed as the possible signature of incommensurate behavior. The primary effect of the pressure was to alter the temperatures at which the phase transitions occurred. Contrary to the behavior expected, the transition temperature for the antiferrorotative transition has a negative pressure coefficient. The spin-lattice and spin-spin relaxation times for the ('35)Cl and ('37)Cl isotopes of the one dimensional XY system, PrCl(,3), were measured at 4.2K. The spin-lattice relaxation is exponential and dominated by magnetic dipole -dipole interactions. The spin-spin relaxation is non-exponential and dominated by electric quadrupolar interactions arising from the coupling of the electric dipole moment at the praseodymium site and the quadrupole moment of the chlorine ion. The temperature dependence of the spin-spin relaxation time was investigated. At 17.4 K both magnetic dipolar and electric

  9. Experimental evidence for ferromagnetic spin-pairing superconductivity emerging in UGe2 : A Ge73 -nuclear-quadrupole-resonance study under pressure

    NASA Astrophysics Data System (ADS)

    Harada, A.; Kawasaki, S.; Mukuda, H.; Kitaoka, Y.; Haga, Y.; Yamamoto, E.; Ōnuki, Y.; Itoh, K. M.; Haller, E. E.; Harima, H.

    2007-04-01

    We report that a different type of superconducting order parameter has been realized in the ferromagnetic states in UGe2 via Ge73 -nuclear-quadrupole-resonance experiments performed under pressure (P) . Measurements of the nuclear spin-lattice relaxation rate (1/T1) have revealed an unconventional nature of superconductivity such that the up-spin band is gapped with line nodes, but the down-spin band remains gapless at the Fermi level. This result is consistent with that of a ferromagnetic spin-pairing model in which Cooper pairs are formed among ferromagnetically polarized electrons. The present experiment has shed light on the possible origin of ferromagnetic superconductivity, which is mediated by ferromagnetic spin-density fluctuations relevant to the first-order transition inside the ferromagnetic states.

  10. Strong coupling between antiferromagnetic and superconducting order parameters of CeRhIn5 studied by I115n nuclear quadrupole resonance spectroscopy

    NASA Astrophysics Data System (ADS)

    Yashima, M.; Mukuda, H.; Kitaoka, Y.; Shishido, H.; Settai, R.; Ōnuki, Y.

    2009-06-01

    We report on a pressure (P) -induced evolution of magnetism and superconductivity (SC) in a helical magnet CeRhIn5 with an incommensurate wave vector Qi=((1)/(2),(1)/(2),0.297) through the I115n nuclear quadrupole resonance (NQR) measurements under P . Systematic measurements of the I115n -NQR spectrum reveal that the commensurate antiferromagnetism (AFM) with Qc=((1)/(2),(1)/(2),(1)/(2)) is realized above Pm˜1.7GPa . An important finding is that the size of SC gap and Tc increase as the magnitude of the AFM moment decreases in the P region, where SC uniformly coexists with the commensurate AFM. This result provides evidence of strong coupling between the commensurate AFM order parameter (OP) and SC OP.

  11. Ferromagnetic critical behavior in U(Co1-xFex)Al (0 ≤x ≤0.02 ) studied by 59Co nuclear quadrupole resonance measurements

    NASA Astrophysics Data System (ADS)

    Karube, K.; Hattori, T.; Ishida, K.; Kimura, N.

    2015-02-01

    In order to investigate physical properties around a ferromagnetic (FM) quantum transition point and a tricritical point (TCP) in the itinerant-electron metamagnetic compound UCoAl, we have performed the 59Co nuclear quadrupole resonance (NQR) measurement for the Fe-substituted U(Co1-xFex)Al(x =0 ,0.5 ,1 ,and2 %) in zero external magnetic field. The Fe concentration dependence of 59Co -NQR spectra at low temperatures indicates that the first-order FM transition occurs at least above x =1 % . The magnetic fluctuations along the c axis detected by the nuclear spin-spin relaxation rate 1 /T2 exhibit an anomaly at Tmax˜20 K and enhance with increasing x . These results are in good agreement with theoretical predictions and indicate the presence of prominent critical fluctuations at the TCP in this system.

  12. Identification of unknown pesticides in fruits using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Imazalil as a case study of quantification.

    PubMed

    Picó, Yolanda; la Farré, Marinel; Soler, Carla; Barceló, Damià

    2007-12-28

    Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QqTOF-MS) is an emerging technique offering more rapid and efficient separation, as well as the possibility to obtain accurate mass measurement and tandem mass spectrometry (MS/MS). This paper deals with the use of UPLC-QqTOF-MS to identify the pesticide residues present in complex pear extracts. Carbendazim, imazalil, and ethoxyquin were successfully identified because of the accurate mass determination of their protonated molecule and their major fragments in the product ion mass spectra. A few plastic and latex additives were also found, most of them probably coming from the packaging transfer to the fruits. The potential of the UPLC-QqTOF-MS and UPLC-QqTOF-MS/MS techniques as a quantification tool is also discussed taking imazalil as example. For quantification, calibration curves were linear over a dynamic range of 2 orders of magnitude, whereas higher calibration ranges are better adjusted to polynomial curves of second and third order. Quantification using different mass windows was also assessed. Accurate quantification required mass windows as wide as 20 mDa, narrower mass windows of 5 mDa provided erroneous quantification, probably because the low ion abundance. The mean recoveries and percentage relative standard deviation (RSD) of 35 determinations for imazalil were 76% (13% RSD) by MS and 77% (14% RSD) by MS/MS. The theoretical limit of detection was 0.4 microg kg(-1), with a validated limit of quantification of 2 microg kg(-1). The quantitative data obtained using UPLC-QqTOF-MS were compared with those obtained using conventional liquid chromatography (LC)-MS/MS with a triple quadrupole (QqQ). It was concluded that UPLC-QqTOF-MS might become a powerful analytical tool for both, unknown's identification and quantification of target pesticides.

  13. Theoretical studies of molecular interactions

    SciTech Connect

    Lester, W.A. Jr.

    1993-12-01

    This research program is directed at extending fundamental knowledge of atoms and molecules including their electronic structure, mutual interaction, collision dynamics, and interaction with radiation. The approach combines the use of ab initio methods--Hartree-Fock (HF) multiconfiguration HF, configuration interaction, and the recently developed quantum Monte Carlo (MC)--to describe electronic structure, intermolecular interactions, and other properties, with various methods of characterizing inelastic and reaction collision processes, and photodissociation dynamics. Present activity is focused on the development and application of the QMC method, surface catalyzed reactions, and reorientation cross sections.

  14. Nuclear shape coexistence in Po isotopes: An interacting boson model study

    NASA Astrophysics Data System (ADS)

    García-Ramos, J. E.; Heyde, K.

    2015-09-01

    Background: The lead region, Po, Pb, Hg, and Pt, shows up the presence of coexisting structures having different deformation and corresponding to different particle-hole configurations in the shell-model language. Purpose: We intend to study the importance of configuration mixing in the understanding of the nuclear structure of even-even Po isotopes, where the shape coexistence phenomena are not clear enough. Method: We study in detail a long chain of polonium isotopes, Po-208190, using the interacting boson model with configuration mixing (IBM-CM). We fix the parameters of the Hamiltonians through a least-squares fit to the known energies and absolute B (E 2 ) transition rates of states up to 3 MeV. Results: We obtained the IBM-CM Hamiltonians and we calculate excitation energies, B (E 2 ) 's, electric quadrupole moments, nuclear radii and isotopic shifts, quadrupole shape invariants, wave functions, and deformations. Conclusions: We obtain a good agreement with the experimental data for all the studied observables and we conclude that shape coexistence phenomenon is hidden in Po isotopes, very much as in the case of the Pt isotopes.

  15. Quadrupole magnet for a rapid cycling synchrotron

    SciTech Connect

    Witte, H.; Berg, J. S.

    2015-05-03

    Rapid Cycling Synchrotrons (RCS) feature interleaved warm and cold dipole magnets; the field of the warm magnets is used to modulate the average bending field depending on the particle energy. It has been shown that RCS can be an attractive option for fast acceleration of particles, for example, muons, which decay quickly. In previous studies it was demonstrated that in principle warm dipole magnets can be designed which can provide the required ramp rates, which are equivalent to frequencies of about 1 kHz. To reduce the losses it is beneficial to employ two separate materials for the yoke; it was also shown that by employing an optimized excitation coil geometry the eddy current losses are acceptable. In this paper we show that the same principles can be applied to quadrupole magnets targeting 30 T/m with a repetition rate of 1kHz and good field quality.

  16. A decoherence-free subspace in a charge quadrupole qubit

    NASA Astrophysics Data System (ADS)

    Friesen, Mark; Ghosh, Joydip; Eriksson, M. A.; Coppersmith, S. N.

    2017-06-01

    Quantum computing promises significant speed-up for certain types of computational problems. However, robust implementations of semiconducting qubits must overcome the effects of charge noise that currently limit coherence during gate operations. Here we describe a scheme for protecting solid-state qubits from uniform electric field fluctuations by generalizing the concept of a decoherence-free subspace for spins, and we propose a specific physical implementation: a quadrupole charge qubit formed in a triple quantum dot. The unique design of the quadrupole qubit enables a particularly simple pulse sequence for suppressing the effects of noise during gate operations. Simulations yield gate fidelities 10-1,000 times better than traditional charge qubits, depending on the magnitude of the environmental noise. Our results suggest that any qubit scheme employing Coulomb interactions (for example, encoded spin qubits or two-qubit gates) could benefit from such a quadrupolar design.

  17. Field quality measurements and abalysis of the LARP technology quadrupole models

    SciTech Connect

    Bossert, R.; Chlachidze, G.; DiMarco, J.; Kashikhin, V.V.; Lamm, M.; Schlabach, P.; Tartaglia, M.; Tompkins, J.C.; Velev, G.V.; Zlobin, A.V.; Caspi, S.; /Fermilab /LBL, Berkeley

    2007-08-01

    One of the US-LHC accelerator research program goals is to develop and prove the design and technology of Nb{sub 3}Sn quadrupoles for an upgrade of the LHC Interaction Region (IR) inner triplets. Four 1-m long technology quadrupole models with a 90 mm bore and field gradient of 200 T/m based on similar coils and different mechanical structures have been developed. In this paper, we present the field quality measurements of the first several models performed at room temperature as well as at superfluid helium temperature in a wide field range. The measured field harmonics are compared to the calculated ones. The field quality of Nb{sub 3}Sn quadrupole models is compared with the NbTi quadrupoles recently produced at Fermilab for the first generation LHC IRs.

  18. Field Quality Measurements and Analysis of the LARP Technology Quadrupole Models

    SciTech Connect

    Chlachidze, G.; DiMarco, J.; Kashikhin, V.V.; Lamm, M.; Schlabach, P.; Tartaglia, M.; Tompkins, J.C.; Velev, G.V.; Zlobin, A.V.; Caspi, S.; Ferracin, P.; Sabbi, G.I.; Bossert, R.

    2008-06-01

    One of the US-LHC accelerator research program goals is to develop and prove the design and technology of Nb{sub 3}Sn quadrupoles for an upgrade of the LHC Interaction Region (IR) inner triplets. Four 1-m long technology quadrupole models with a 90 mm bore and field gradient of 200 T/m based on similar coils and different mechanical structures have been developed. In this paper, we present the field quality measurements of the first several models performed at room temperature as well as at superfluid helium temperature in a wide field range. The measured field harmonics are compared to the calculated ones. The field quality of Nb{sub 3}Sn quadrupole models is compared with the NbTi quadrupoles recently produced at Fermilab for the first generation LHC IRs.

  19. Dipole-quadrupole Förster resonance in cesium Rydberg gas

    NASA Astrophysics Data System (ADS)

    Maineult, Wilfried; Pelle, Bruno; Faoro, Riccardo; Arimondo, Ennio; Pillet, Pierre; Cheinet, Patrick

    2016-11-01

    The resonant energy transfer between two close particles, also known as Förster resonance in atomic or biological systems, is usually associated with dipole-dipole interaction. In Rydberg atoms, it is a widely used tool to enhance the interactions between particles. Here, we observe a resonant energy transfer between Rydberg atoms that cannot be attributed to a dipole-dipole interaction, owing to selection rules, and comes instead from an efficient dipole-quadrupole process. We compare the measured probability transfer with a theoretical model including quadrupolar terms and find very good agreement with our measurement. Further studies of those multipolar resonances should probe their dependences on various parameters (quantum numbers, relative orientation of the atoms), and may find some applications in quantum procedures where dipole-dipole resonance cannot be used, for instance where the states of interest have a difference in angular momentum of two.

  20. A Merged Quadrupole-Calorimeter for CEPC

    NASA Astrophysics Data System (ADS)

    Talman, Richard; Hauptman, John

    The luminosity 𝓛 of colliding beams in a storage ring such as CEPC depends strongly on l*, the half-length of the free space centered on the intersection point (IP). l* is also the length from the IP to the front edges of the two near-in quadrupoles that are focusing the counter-circulating beams to the IP spot. The detector length cannot, therefore, exceed 2l*. Since 𝓛 increases strongly with decreasing l*, there is incentive for reducing l*; but this requires the detector to be shorter than desirable. This paper proposes a method for integrating these adjacent quadrupoles into the particle detector to retain (admittedly degraded) active particle detection of those forward going particles that would otherwise be obscured by the quadrupole. A gently conical quadrupole shape is more natural for merging the quadrupole into the particle detector than is the analytically exact cylindrical shape. This is true whether or not the calorimeter is integrated. It will be the task of accelerator physicists to determine the extent to which deviation from the pure quadrupole field compromises (or improves) accelerator performance. Superficially, both the presence of strongest gradient close to the IP and largest aperture farther from the IP seem to be advantageous. A tentative design for this merged, quadrupole-calorimeter is given.

  1. A merged quadrupole-calorimeter for CEPC

    NASA Astrophysics Data System (ADS)

    Talman, Richard; Hauptman, John

    2016-11-01

    The luminosity ℒ of colliding beams in a storage ring such as CEPC depends strongly on l∗, the half-length of the free space centered on the intersection point (IP). l∗ is also the length from the IP to the front edges of the two near-in quadrupoles that are focusing the counter-circulating beams to the IP spot. The detector length cannot, therefore, exceed 2l∗. Since ℒ increases strongly with decreasing l∗, there is incentive for reducing l∗; but this requires the detector to be shorter than desirable. This paper proposes a method for integrating these adjacent quadrupoles into the particle detector to retain (admittedly degraded) active particle detection of those forward going particles that would otherwise be obscured by the quadrupole. A gently conical quadrupole shape is more natural for merging the quadrupole into the particle detector than is the analytically exact cylindrical shape. This is true whether or not the calorimeter is integrated. It will be the task of accelerator physicists to determine the extent to which deviation from the pure quadrupole field compromises (or improves) accelerator performance. Superficially, both the presence of strongest gradient close to the IP and largest aperture farther from the IP seem to be advantageous. A tentative design for this merged, quadrupole-calorimeter is given.

  2. Targeted proteomic quantification on quadrupole-orbitrap mass spectrometer.

    PubMed

    Gallien, Sebastien; Duriez, Elodie; Crone, Catharina; Kellmann, Markus; Moehring, Thomas; Domon, Bruno

    2012-12-01

    There is an immediate need for improved methods to systematically and precisely quantify large sets of peptides in complex biological samples. To date protein quantification in biological samples has been routinely performed on triple quadrupole instruments operated in selected reaction monitoring mode (SRM), and two major challenges remain. Firstly, the number of peptides to be included in one survey experiment needs to be increased to routinely reach several hundreds, and secondly, the degree of selectivity should be improved so as to reliably discriminate the targeted analytes from background interferences. High resolution and accurate mass (HR/AM) analysis on the recently developed Q-Exactive mass spectrometer can potentially address these issues. This instrument presents a unique configuration: it is constituted of an orbitrap mass analyzer equipped with a quadrupole mass filter as the front-end for precursor ion mass selection. This configuration enables new quantitative methods based on HR/AM measurements, including targeted analysis in MS mode (single ion monitoring) and in MS/MS mode (parallel reaction monitoring). The ability of the quadrupole to select a restricted m/z range allows one to overcome the dynamic range limitations associated with trapping devices, and the MS/MS mode provides an additional stage of selectivity. When applied to targeted protein quantification in urine samples and benchmarked with the reference SRM technique, the quadrupole-orbitrap instrument exhibits similar or better performance in terms of selectivity, dynamic range, and sensitivity. This high performance is further enhanced by leveraging the multiplexing capability of the instrument to design novel acquisition methods and apply them to large targeted proteomic studies for the first time, as demonstrated on 770 tryptic yeast peptides analyzed in one 60-min experiment. The increased quality of quadrupole-orbitrap data has the potential to improve existing protein

  3. Relativistic Theory of the Electric Quadrupole Moment of a Hydrogen-Like Atom in the s{sub 1/2} and p{sub 1/2} States

    SciTech Connect

    Kozhedub, Yu.S.; Shabaev, V.M.

    2005-10-15

    Relativistic analytical expressions are derived for the electric quadrupole moment induced by the hyperfine interaction of the electron with the nucleus of a hydrogen-like atom in the ns{sub 1/2} and np{sub 1/2} states. The magnetic dipole and electric quadrupole hyperfine interactions are taken into account. The calculations are performed using the generalized virial relationships for the Dirac equation in a central field. The dependences of the electric quadrupole moment on the nuclear charge Z and the principal quantum number n are analyzed. The induced quadrupole moments are compared with the nuclear quadrupole moments.

  4. Global analysis of quadrupole shape invariants based on covariant energy density functionals

    NASA Astrophysics Data System (ADS)

    Quan, S.; Chen, Q.; Li, Z. P.; Nikšić, T.; Vretenar, D.

    2017-05-01

    Background: The coexistence of different geometric shapes at low energies presents a universal structure phenomenon that occurs over the entire chart of nuclides. Studies of the shape coexistence are important for understanding the microscopic origin of collectivity and modifications of shell structure in exotic nuclei far from stability. Purpose: The aim of this work is to provide a systematic analysis of characteristic signatures of coexisting nuclear shapes in different mass regions, using a global self-consistent theoretical method based on universal energy density functionals and the quadrupole collective model. Method: The low-energy excitation spectrum and quadrupole shape invariants of the two lowest 0+ states of even-even nuclei are obtained as solutions of a five-dimensional collective Hamiltonian (5DCH) model, with parameters determined by constrained self-consistent mean-field calculations based on the relativistic energy density functional PC-PK1, and a finite-range pairing interaction. Results: The theoretical excitation energies of the states, 21+,41+,02+,22+,23+, as well as the B (E 2 ;01+→21+) values, are in very good agreement with the corresponding experimental values for 621 even-even nuclei. Quadrupole shape invariants have been implemented to investigate shape coexistence, and the distribution of possible shape-coexisting nuclei is consistent with results obtained in recent theoretical studies and available data. Conclusions: The present analysis has shown that, when based on a universal and consistent microscopic framework of nuclear density functionals, shape invariants provide distinct indicators and reliable predictions for the occurrence of low-energy coexisting shapes. This method is particularly useful for studies of shape coexistence in regions far from stability where few data are available.

  5. Molecular Electronic Environment from Methyl Torsion and 14N Quadrupole Coupling

    NASA Astrophysics Data System (ADS)

    Gurusinghe, Ranil M.; Tubergen, Michael

    2016-06-01

    Methyl rotors are sensitive indicators of the local and non-local electronic environment, so a study of methyl torsional barriers at different sites around the perimeter of a conjugated ring system may reveal electronic environment of the indole ring. Previously reported resultsa are limited to microwave spectroscopic identification of the 1-methylindole, 2-methylindole, 3-methylindole, and 5-methylindole. The new measurements of 4-methylindole, 6-methylindole, and 7-methylindole complete the series. Over one thousand transitions were assigned in the 10.5 - 21 GHz frequency range, resolving both nuclear quadrupole coupling and methyl internal rotation for all seven species. Electronic structure calculations at MP2/6-311++G(d,p) level, torsional barrier calculations and molecular electrostatic potential maps at ωB97XD/6-311++G(d,p) level are used along with the experimental data. 14N nuclear quadrupole coupling tensor elements were used to determine the ionic character of the NH sigma bond, π bonding character of the nitrogen pz orbital, and the amount of negative charge on the nitrogen of each methylindole. Fitted torsional barriers were compared with theoretical investigations of the origin of methyl torsional barriers to confirm that overall barrier arises from both hyperconjugative interactions and structural interactions of bonding and anti-bonding orbitals. aR. M. Gurusinghe, M. J. Tubergen. 69th International Symposium of Molecular Spectroscopy, Urbana-Champaign, IL, 2014, RJ03.

  6. Liquid chromatographic/electrospray ionization quadrupole/time of flight tandem mass spectrometric study of polyphenolic composition of different Vaccinium berry species and their comparative evaluation.

    PubMed

    Ancillotti, Claudia; Ciofi, Lorenzo; Rossini, Daniele; Chiuminatto, Ugo; Stahl-Zeng, Jianru; Orlandini, Serena; Furlanetto, Sandra; Del Bubba, Massimo

    2017-02-01

    Ultra-high-performance liquid chromatography coupled with high-resolution quadrupole-time of flight mass spectrometry with both negative and positive ionization was used for comprehensively investigating the phenolic and polyphenolic compounds in berries from three spontaneous or cultivated Vaccinium species (i.e., Vaccinium myrtillus, Vaccinium uliginosum subsp. gaultherioides, and Vaccinium corymbosum). More than 200 analytes, among phenolic and polyphenolic compounds belonging to the classes of anthocyanins, monomeric and oligomeric flavonols, flavanols, dihydrochalcones, phenolic acids, together with other polyphenolic compounds of mixed structural characteristics, were identified. Some of the polyphenols herein investigated, such as anthocyanidin glucuronides and malvidin-feruloyl-hexosides in V. myrtillus, or anthocyanindin aldopentosides and coumaroyl-hexosides in V. uliginosum subsp. gaultherioides and a large number of proanthocyanidins with high molecular weight in all species, were described for the first time in these berries. Principal component analysis applied on original LC-TOF data, acquired in survey scan mode, successfully discriminated the three Vaccinium berry species investigated, on the basis of their polyphenolic composition, underlying one more time the fundamental role of mass spectrometry for food characterization.

  7. Nonuniform radiation damage in permanent magnet quadrupoles.

    PubMed

    Danly, C R; Merrill, F E; Barlow, D; Mariam, F G

    2014-08-01

    We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL's pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

  8. Nonuniform radiation damage in permanent magnet quadrupoles

    SciTech Connect

    Danly, C. R.; Merrill, F. E.; Barlow, D.; Mariam, F. G.

    2014-08-15

    We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL’s pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

  9. Antiferromagnetic Spin Fluctuations and Unconventional Nodeless Superconductivity in an Iron-Based New Superconductor (Ca4Al2O6-y)(Fe2As2): As75 Nuclear Quadrupole Resonance Study

    NASA Astrophysics Data System (ADS)

    Kinouchi, H.; Mukuda, H.; Yashima, M.; Kitaoka, Y.; Shirage, P. M.; Eisaki, H.; Iyo, A.

    2011-07-01

    We report As75 nuclear quadrupole resonance studies on (Ca4Al2O6-y)(Fe2As2) with Tc=27K. Measurement of nuclear-spin-relaxation rate 1/T1 has revealed a significant development of two-dimensional antiferromagnetic spin fluctuations down to Tc in association with the smallest As-Fe-As bond angle. Below Tc, the temperature dependence of 1/T1 without any trace of the coherence peak is well accounted for by a nodeless s±-wave multiple-gaps model. From the fact that its Tc is comparable to Tc=28K in the optimally doped LaFeAsO1-y in which antiferromagnetic spin fluctuations are not dominant, we remark that antiferromagnetic spin fluctuations are not a unique factor for enhancing Tc among Fe-based superconductors, but a condition for optimizing superconductivity should be addressed from the lattice structure point of view.

  10. Statistical thermodynamics of fluids with both dipole and quadrupole moments.

    PubMed

    Benavides, Ana L; Delgado, Francisco J García; Gámez, Francisco; Lago, Santiago; Garzón, Benito

    2011-06-21

    New Gibbs ensemble simulation data for a polar fluid modeled by a square-well potential plus dipole-dipole, dipole-quadrupole, and quadrupole-quadrupole interactions are presented. This simulation data is used in order to assess the applicability of the multipolar square-well perturbation theory [A. L. Benavides, Y. Guevara, and F. del Río, Physica A 202, 420 (1994)] to systems where more than one term in the multipole expansion is relevant. It is found that this theory is able to reproduce qualitatively well the vapor-liquid phase diagram for different multipolar moment strengths, corresponding to typical values of real molecules, except in the critical region. Hence, this theory is used to model the behavior of substances with multiple chemical bonds such as carbon monoxide and nitrous oxide and we found that with a suitable choice of the values of the intermolecular parameters, the vapor-liquid equilibrium of these species is adequately estimated. © 2011 American Institute of Physics

  11. Statistical thermodynamics of fluids with both dipole and quadrupole moments

    NASA Astrophysics Data System (ADS)

    Benavides, Ana L.; García Delgado, Francisco J.; Gámez, Francisco; Lago, Santiago; Garzón, Benito

    2011-06-01

    New Gibbs ensemble simulation data for a polar fluid modeled by a square-well potential plus dipole-dipole, dipole-quadrupole, and quadrupole-quadrupole interactions are presented. This simulation data is used in order to assess the applicability of the multipolar square-well perturbation theory [A. L. Benavides, Y. Guevara, and F. del Río, Physica A 202, 420 (1994), 10.1016/0378-4371(94)90469-3] to systems where more than one term in the multipole expansion is relevant. It is found that this theory is able to reproduce qualitatively well the vapor-liquid phase diagram for different multipolar moment strengths, corresponding to typical values of real molecules, except in the critical region. Hence, this theory is used to model the behavior of substances with multiple chemical bonds such as carbon monoxide and nitrous oxide and we found that with a suitable choice of the values of the intermolecular parameters, the vapor-liquid equilibrium of these species is adequately estimated.

  12. Electron Cloud Generation And Trapping in a Quadrupole Magnet at the Los Alamos PSR

    SciTech Connect

    Macek, R.J.; Browman, A.A.; Ledford, J.E.; Borden, M.J.; O'Hara, J.F.; McCrady, R.C.; Rybarcyk, L.J.; Spickermann, T.; Zaugg, T.J.; Pivi, M.T.F.; /SLAC

    2007-11-14

    A diagnostic to measure electron cloud formation and trapping in a quadrupole magnet has been developed, installed, and successfully tested at PSR. Beam studies with this diagnostic show that the electron flux striking the wall in the quadrupole is comparable to or larger than in an adjacent drift. In addition, the trapped electron signal, obtained using the sweeping feature of diagnostic, was larger than expected and decayed very slowly with an exponential time constant of 50 to 100 {micro}s. Experimental results were also obtained which suggest that a significant fraction of the electrons observed in the adjacent drift space were seeded by electrons ejected from the quadrupole.

  13. Permanent magnet edge-field quadrupole

    DOEpatents

    Tatchyn, Roman O.

    1997-01-01

    Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.

  14. Permanent magnet edge-field quadrupole

    DOEpatents

    Tatchyn, R.O.

    1997-01-21

    Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis. 10 figs.

  15. Commissioning of helium injector for coupled radio frequency quadrupole and separated function radio frequency quadrupole accelerator.

    PubMed

    Peng, Shixiang; Chen, Jia; Ren, Haitao; Zhao, Jie; Xu, Yuan; Zhang, Tao; Zhang, Ailing; Xia, Wenlong; Gao, Shuli; Wang, Zhi; Luo, Yuting; Guo, Zhiyu; Chen, Jia'er

    2014-02-01

    A project to study a new type of acceleration structure has been launched at Peking University, in which a traditional radio frequency quadrupole (RFQ) and a separated function radio frequency quadrupole are coupled in one cavity to accelerate the He+ beam. A helium injector for this project is developed. The injector consists of a 2.45 GHz permanent magnet electron cyclotron resonance ion source and a 1.16 m long low energy beam transport (LEBT). The commissioning of this injector was carried out and an onsite test was held in June 2013. A 14 mA He+ beam with the energy of 30 keV has been delivered to the end of the LEBT, where a diaphragm with the diameter of 7 mm is located. The position of the diaphragm corresponds to the entrance of the RFQ electrodes. The beam emittance and fraction were measured after the 7 mm diaphragm. Its rms emittance is about 0.14 π mm mrad and the fraction of He+ is about 99%.

  16. Commissioning of helium injector for coupled radio frequency quadrupole and separated function radio frequency quadrupole accelerator

    SciTech Connect

    Peng, Shixiang Chen, Jia; Ren, Haitao; Zhao, Jie; Xu, Yuan; Zhang, Tao; Xia, Wenlong; Gao, Shuli; Wang, Zhi; Luo, Yuting; Guo, Zhiyu; Zhang, Ailing; Chen, Jia'er

    2014-02-15

    A project to study a new type of acceleration structure has been launched at Peking University, in which a traditional radio frequency quadrupole (RFQ) and a separated function radio frequency quadrupole are coupled in one cavity to accelerate the He+ beam. A helium injector for this project is developed. The injector consists of a 2.45 GHz permanent magnet electron cyclotron resonance ion source and a 1.16 m long low energy beam transport (LEBT). The commissioning of this injector was carried out and an onsite test was held in June 2013. A 14 mA He+ beam with the energy of 30 keV has been delivered to the end of the LEBT, where a diaphragm with the diameter of 7 mm is located. The position of the diaphragm corresponds to the entrance of the RFQ electrodes. The beam emittance and fraction were measured after the 7 mm diaphragm. Its rms emittance is about 0.14 π mm mrad and the fraction of He+ is about 99%.

  17. Integrally formed radio frequency quadrupole

    DOEpatents

    Abbott, Steven R.

    1989-01-01

    An improved radio frequency quadrupole (10) is provided having an elongate housing (11) with an elongate central axis (12) and top, bottom and two side walls (13a-d) symmetrically disposed about the axis, and vanes (14a-d) formed integrally with the walls (13a-d), the vanes (14a-d) each having a cross-section at right angles to the central axis (12) which tapers inwardly toward the axis to form electrode tips (15a-d) spaced from each other by predetermined distances. Each of the four walls (13a-d), and the vanes (14a-d) integral therewith, is a separate structural element having a central lengthwise plane (16) passing through the tip of the vane, the walls (13a-d) having flat mounting surfaces (17, 18) at right angles to and parallel to the control plane (16), respectively, which are butted together to position the walls and vane tips relative to each other.

  18. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1997-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  19. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1998-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  20. Permanent Magnet Skew Quadrupoles for the Low Emittance LER Lattice of PEP-II

    SciTech Connect

    Decker, F.-J.; Anderson, S.; Kharakh, D.; Sullivan, M.; /SLAC

    2011-07-05

    The vertical emittance of the low energy ring (LER) in the PEP-II B-Factory was reduced by using skew quadrupoles consisting of permanent magnet material. The advantages over electric quadrupoles or rotating existing normal quadrupoles are discussed. To assure a high field quality, a Biot-Savart calculation was used to cancel the natural 12-pole component by using different size poles over a few layers. A magnetic measurement confirmed the high quality of the magnets. After installation and adjusting the original electric 12 skew and 16 normal quadrupoles the emittance contribution from the region close to the interaction point, which was the biggest part in the original design, was considerably reduced. To strengthen the vertical behavior of the LER beam, a low emittance lattice was developed. It lowered the original vertical design emittance from 0.54 nm-rad to 0.034 nm-rad. In order to achieve this, additional skew quadrupoles were required to bring the coupling correction out of the arcs and closer to the detector solenoid in the straight (Fig. 1). It is important, together with low vertical dispersion, that the low vertical emittance is not coupled into the horizontal, which is what we get if the coupling correction continues into the arcs. Further details of the lattice work is described in another paper; here we concentrate on the development of the permanent skew (PSK) quadrupole solution. Besides the permanent magnets there are two other possibilities, using electric magnets or rotating normal quadrupoles. Electric magnets would have required much more additional equipment like magnets stands, power supply, and new vacuum chamber sections. Rotating existing quadrupoles was also not feasible since they are mostly mounted together with a bending magnet on the same support girder.

  1. Synergistic use of Knudsen effusion quadrupole mass spectrometry, solid-state galvanic cell and differential scanning calorimetry for thermodynamic studies on lithium aluminates

    NASA Astrophysics Data System (ADS)

    Rakshit, S. K.; Naik, Y. P.; Parida, S. C.; Dash, Smruti; Singh, Ziley; Sen, B. K.; Venugopal, V.

    2008-06-01

    Three ternary oxides LiAl 5O 8(s), LiAlO 2(s) and Li 5AlO 4(s) in the system Li-Al-O were prepared by solid-state reaction route and characterized by X-ray powder diffraction method. Equilibrium partial pressure of CO 2(g) over the three-phase mixtures {LiAl 5O 8(s)+Li 2CO 3(s)+5Al 2O 3(s)}, {LiAl 5O 8(s)+5LiAlO 2(s)+2Li 2CO 3(s)} and {LiAlO 2(s)+Li 5AlO 4(s)+2Li 2CO 3(s)} were measured using Knudsen effusion quadrupole mass spectrometry (KEQMS). Solid-state galvanic cell technique based on calcium fluoride electrolyte was used to determine the standard molar Gibbs energies of formations of these aluminates. The standard molar Gibbs energies of formation of these three aluminates calculated from KEQMS and galvanic cell measurements were in good agreement. Heat capacities of individual ternary oxides were measured from 127 to 868 K using differential scanning calorimetry. Thermodynamic tables representing the values of Δ fH0(298.15 K), S0(298.15 K) S0( T), Cp0( T), H0( T), { H0( T)- H0(298.15 K)}, G0( T), Δ fH0( T), Δ fG 0( T) and free energy function (fef) were constructed using second law analysis and FACTSAGE thermo-chemical database software.

  2. Information technology in chemistry research and education: Part I. Ab initio studies on the hydrolysis of aromatic diazonium ions. Part II. Theoretical study and molecular modeling of non-covalent interactions. Part III. Applying information technology in chemistry education

    NASA Astrophysics Data System (ADS)

    Wu, Zhengyu

    Part I of this dissertation studies the bonding in chemical reactions, while Part II studies the bonding related to inter- and intra-molecular interactions. Part III studies the application of IT technology in chemistry education. Part I of this dissertation (chapter 1 and chapter 2) focuses on the theoretical studies on the mechanism of the hydrolysis reactions of benzenediazonium ion and guaninediazonium ion. The major conclusion is that in hydrolysis reactions the "unimolecular mechanism" actually has to involve the reacting solvent molecule. Therefore, the unimolecular pathway can only serve as a conceptual model but will not happen in the reality. Chapter I concludes that the hydrolysis reaction of benzenediazonium ion takes the direct SN2Ar mechanism via a transition state but without going through a pre-coordination complex. Chapter 2 concludes that the formation of xanthine from the dediazoniation reaction of guaninediazonium ion in water takes the SN2Ar pathway without a transition state. And oxanine might come from an intermediate formed by the bimolecular deprotonation of the H atom on N3 of guaninediazonium ion synchronized with the pyrimidine ring opening reaction. Part II of this dissertation includes chapters 3, 4, and 5. Chapter 3 studies the quadrupole moment of benzene and quadrupole-quadrupole interactions. We concluded that the quadrupole-quadrupole interaction is important in the arene-arene interactions. Our study shows the most stable structure of benzene dimer is the point-to-face T-shaped structure. Chapter 4 studies the intermolecular interactions that result in the disorder of the crystal of 4-Chloroacetophenone-(4-methoxyphenylethylidene). We analyzed all the nearest neighbor interactions within that crystal and found that the crystal structure is determined by its thermo-dynamical properties. Our calculation perfectly reproduced the percentage of parallel-alignment of the crystal. Part III of this dissertation is focused on the

  3. Solar Wind Interaction with Mercury's Magnetosphere: a Simulation Study

    NASA Astrophysics Data System (ADS)

    Richer, E.; Chanteur, G. M.; Modolo, R.; Leblanc, F.; Hess, S.

    2012-04-01

    Three flybys of Mercury by Mariner 10, numerous terrestrial observations of Mercury's exosphere and MESSENGER observations during flybys and orbital operations have brought important information about the Hermean environment. Mercury's intrinsic magnetic field is principally dipolar and its interaction with the Solar Wind (SW) creates a small and very dynamic magnetosphere. Mercury's exosphere is a highly variable and complex neutral environment made of several species: H, He, O, Na, K, Ca, and Mg have already been detected. MESSENGER is in orbit around Mercury, since March 2011, with a polar trajectory and a periapsis located near the north geographic pole. MESSENGER observations lead to a new description of the source of the intrinsic magnetic field : a northward shifted dipole of 500 km seems to better fit the magnetic field observations at northern latitudes higher than 30°, than former models (Anderson et al, 2011). However the lack of low altitude observations above the southern hemisphere does not allow definitive conclusions about the topology of the planetary magnetic field at high southern latitudes. Global simulations can provide complementary information of Mercury's magnetic field structure and its global interaction with the solar wind. This study presents simulation results from a 3-dimensional parallel multi-species hybrid model of Mercury's magnetosphere interaction with the SW. The SW in this model is representative of conditions at Mercury's aphelion (0.47AU) and is composed of 95% protons and 5% alpha particles. The simulated IMF is oriented accordingly to observations during the orbit of MESSENGER on April 23rd of 2011 without component in the north/south direction and a cone angle of about 60°. In addition a neutral corona of sodium is included in this model and is partly ionized by solar photons. Planetary and SW plasmas are treated separately and the dynamic of each ion species can be investigated separately. Simulations have been

  4. Longitudinal capture in the radio-frequency-quadrupole structure

    SciTech Connect

    Inagaki, S.

    1980-03-01

    The radio-frequency-quadrupole (RFQ) linac structure not only can attain easily transverse focusing in the low-beta region, but also can obtain very high capture efficiency because of its low beta-lambda and low-particle rigidity. An optimization study of the zero space-charge longitudinal capture in an RFQ linac that yields configurations with large capture efficiency is described.

  5. Strong and electromagnetic interactions in heavy exotic atoms

    NASA Astrophysics Data System (ADS)

    Delaat, Cornelius Theodorus Adrianus Maria

    1988-03-01

    Phenomena that occur when a negatively charged particle interacts with an atom are studied. The contents include the following: improvements in experimental methods and analysis; theory of hadronic interactions in pionic atoms; systematics of 3d and 4f pionic levels in Ta-181, natural Rhenium, natural Platinum, Au-197, Pb-208, Bi-209, and Np-237; the quadrupole moment of Np-237.

  6. Induced quadrupole effects near a crossover in a tetragonal TbLiF{sub 4} sheelite in a strong magnetic field up to 50 T

    SciTech Connect

    Kazei, Z. A. Snegirev, V. V.; Broto, J.-M.; Abdulsabirov, R. Yu.; Korableva, S. L.

    2012-12-15

    The anomalies of magnetic properties of TbLiF{sub 4} caused by the interaction of the energy levels of a rare-earth ion in a strong magnetic field up to 50 T directed along the [100] and [110] axes are studied experimentally and theoretically. The jumps in magnetization M(H) and the maxima of the differential magnetic susceptibility dM(H)/dH are found in critical fields H{sub c} = 28 and 31 T, where the lower component of the excited doublet approaches the ground-state singlet of a Tb{sup 3+} ion. Based on the crystal-field model with known interaction parameters, we calculated the Zeeman effect and the magnetization and magnetic susceptibility curves for the TbLiF{sub 4} crystal, which adequately describe magnetic anomalies and critical parameters of a crossover. It is shown that the jumpwise change in the {alpha}- and {gamma}-symmetry quadrupole interactions in TbLiF{sub 4} caused by changes in the corresponding quadrupole moments during the crossing of energy levels leads, in accordance with experiments, to a decrease in the critical field H{sub c} by approximately 4 T and an increase in the maximum of the differential susceptibility dM(H)/dH near the crossover more than twofold. This behavior can be considered as an analog of the induced quadrupole transition caused by a change of the ground state of the rare-earth ion during crossover.

  7. Set Up and Test Results for a Vibrating Wire System for Quadrupole Fiducialization

    SciTech Connect

    Levashov, Michael Y.

    2010-12-01

    Quadrupoles will be placed between the undulator segments in LCLS to keep the electron beam focused as it passes through. The quadrupoles will be assembled with their respective undulator segments prior to being placed into the tunnel. Beam alignment will be used to center the quadrupoles, along with the corresponding undulators, on the beam. If there is any displacement between the undulator and the quadrupole axes in the assemblies, the beam will deviate from the undulator axis. If it deviates by more than 80{micro}m in vertical or 140{micro}m in horizontal directions, the undulator will not perform as required by LCLS. This error is divided between three sources: undulator axis fiducialization, quadrupole magnetic axis fiducialization, and assembly of the two parts. In particular, it was calculated that the quadrupole needs to be fiducialized to within 25{micro}m in both vertical and horizontal directions. A previous study suggested using a vibrating wire system for finding the magnetic axis of a quadrupole. The study showed that the method has high sensitivity (up to 1{micro}m) and laid out guidelines for constructing it. There are 3 steps in fiducializing the quadrupole with the vibrating wire system. They are positioning the wire at the magnet center (step 1), finding the wire with position detectors (step 2), and finding the quadrupole tooling ball positions relative to the position detector tooling balls (step 3). The following break up of error was suggested for the fiducialization steps: 10{micro}m for step 1 (finding the center), 20{micro}m for step 2 (finding the wire), and 10{micro}m for step 3 (tooling ball measurements). The purpose of this study is to investigate whether the vibrating wire system meets the requirements for LCLS. In particular, if it can reliably fiducialize a quadrupole magnetic center to within 25{micro}m in both vertical and horizontal directions. The behavior of individual system components is compared to the expected performance

  8. Set Up and Test Results for a Vibrating Wire System for Quadrupole Fiducialization

    SciTech Connect

    Not Available

    2010-11-29

    Quadrupoles will be placed between the undulator segments in LCLS to keep the electron beam focused as it passes through. The quadrupoles will be assembled with their respective undulator segments prior to being placed into the tunnel. Beam alignment will be used to center the quadrupoles, along with the corresponding undulators, on the beam. If there is any displacement between the undulator and the quadrupole axes in the assemblies, the beam will deviate from the undulator axis. If it deviates by more than 80{micro}m in vertical or 140{micro}m in horizontal directions, the undulator will not perform as required by LCLS. This error is divided between three sources: undulator axis fiducialization, quadrupole magnetic axis fiducialization, and assembly of the two parts. In particular, it was calculated that the quadrupole needs to be fiducialized to within 25{micro}m in both vertical and horizontal directions. A previous study suggested using a vibrating wire system for finding the magnetic axis of a quadrupole. The study showed that the method has high sensitivity (up to 1{micro}m) and laid out guidelines for constructing it. There are 3 steps in fiducializing the quadrupole with the vibrating wire system. They are positioning the wire at the magnet center (step 1), finding the wire with position detectors (step 2), and finding the quadrupole tooling ball positions relative to the position detector tooling balls (step 3). The following break up of error was suggested for the fiducialization steps: 10{micro}m for step 1 (finding the center), 20{micro}m for step 2 (finding the wire), and 10{micro}m for step 3 (tooling ball measurements). The purpose of this study is to investigate whether the vibrating wire system meets the requirements for LCLS. In particular, if it can reliably fiducialize a quadrupole magnetic center to within 25{micro}m in both vertical and horizontal directions. The behavior of individual system components is compared to the expected performance

  9. Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice

    SciTech Connect

    Nosochkov, Yuri; Cai, Y.; Jiao, Y.; Wang, M-H.; Fartoukh, S.; Giovannozzi, M.; Maria, R.de; McIntosh, E.

    2012-06-25

    It has been proposed to implement the so-called Achromatic Telescopic Squeezing (ATS) scheme in the LHC high luminosity (HL) lattice to reduce beta functions at the Interaction Points (IP) up to a factor of 8. As a result, the nominal 4.5 km peak beta functions reached in the Inner Triplets (IT) at collision will be increased by the same factor. This, therefore, justifies the installation of new, larger aperture, superconducting IT quadrupoles. The higher beta functions will enhance the effects of the triplet quadrupole field errors leading to smaller beam dynamic aperture (DA). To maintain the acceptable DA, the effects of the triplet field errors must be re-evaluated, thus specifying new tolerances. Such a study has been performed for the so-called '4444' collision option of the HL-LHC layout version SLHCV3.01, where the IP beta functions are reduced by a factor of 4 in both planes with respect to a pre-squeezed value of 60 cm at two collision points. The dynamic aperture calculations were performed using SixTrack. The impact on the triplet field quality is presented.

  10. Development and Test of TQC models, LARP Technological Quadrupole Magnets

    SciTech Connect

    Bossert, R.C.; Ambrosio, G.; Andreev, N.; Barzi, E.; Carcagno, R.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Nobrega, F.; Novitski, I.; Orris, D.; Tartaglia, M.; Zlobin, A.V.; Caspi, S.; Dietderich, D.; Ferracin, P.; Hafalia, A.R.; Sabbi, G.

    2008-06-01

    In support of the development of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade, two-layer quadrupole models (TQC and TQS) with 90mm aperture are being constructed at Fermilab and LBNL within the framework of the US LHC Accelerator Research Program (LARP). This paper describes the development and test of TQC01b, the second TQC model, and the experience during construction of TQE02 and TQC02, subsequent models in the series. ANSYS analysis of the mechanical structure, its underlying assumptions, and changes based on experience with TQC01 are presented and discussed. Construction experience, in-process measurements, and modifications to the assembly since TQC01 are described. The test results presented here include magnet strain and quench performance during training of TQC01b, as well as quench studies of current ramp rate dependence.

  11. Focusing properties of discrete RF quadrupoles

    NASA Astrophysics Data System (ADS)

    Li, Zhi-Hui; Wang, Zhi-Jun

    2017-08-01

    The particle motion equation for a Radio Frequency (RF) quadrupole is derived. The motion equation shows that the general transform matrix of a RF quadrupole with length less than or equal to 0.5βλ (β is the relativistic velocity of particles and λ is wavelength of radio frequency electromagnetic field) can describe the particle motion in an arbitrarily long RF quadrupole. By iterative integration, the general transform matrix of a discrete RF quadrupole is derived from the motion equation. The transform matrix is in form of a power series of focusing parameter B. It shows that for length less than βλ, the series up to the 2nd order of B agrees well with the direct integration results for B up to 30, while for length less than 0.5βλ, the series up to 1st order is already a good approximation of the real solution for B less than 30. The formula of the transform matrix can be integrated into linac or beam line design code to deal with the focusing of discrete RF quadrupoles. Supported by National Natural Science Foundation of China (11375122, 11511140277) and Strategic Priority Research Program of the Chinese Academy of Sciences (XDA03020705)

  12. Induced CMB quadrupole from pointing offsets

    SciTech Connect

    Moss, Adam; Scott, Douglas; Sigurdson, Kris E-mail: dscott@phas.ubc.ca

    2011-01-01

    Recent claims in the literature have suggested that the WMAP quadrupole is not primordial in origin, and arises from an aliasing of the much larger dipole field because of incorrect satellite pointing. We attempt to reproduce this result and delineate the key physics leading to the effect. We find that, even if real, the induced quadrupole would be smaller than the WMAP value. We discuss reasons why the WMAP data are unlikely to suffer from this particular systematic effect, including the implications for observations of point sources. Given this evidence against the reality of the effect, the similarity between the pointing-offset-induced signal and the actual quadrupole then appears to be quite puzzling. However, we find that the effect arises from a convolution between the gradient of the dipole field and anisotropic coverage of the scan direction at each pixel. There is something of a directional conspiracy here — the dipole signal lies close to the Ecliptic Plane, and its direction, together with the WMAP scan strategy, results in a strong coupling to the Y{sub 2,−1} component in Ecliptic co-ordinates. The dominant strength of this component in the measured quadrupole suggests that one should exercise increased caution in interpreting its estimated amplitude. The Planck satellite has a different scan strategy which does not so directly couple the dipole and quadrupole in this way and will soon provide an independent measurement.

  13. Reexamining the nuclear structure of 154Gd in the dynamic pairing plus quadrupole model

    NASA Astrophysics Data System (ADS)

    Gupta, J. B.; Hamilton, J. H.

    2017-05-01

    In a previous study of the collective multiphonon bands in 154Gd, using the microscopic dynamic pairing plus quadrupole model, data for eight K bands were analyzed. In the last four decades, its decay scheme is significantly revised and the nuclear theory has undergone a significant change. Special focus is on new weak intensity transitions in several bands and on the reassigned levels in its decay scheme. The present study represents a detailed revised analysis of the collective even parity bands below 2.1 MeV. Also, a discussion is given on the nature of the Kπ=0+ excited bands, validity of band mixing approach, and of the assumption of shape coexistence of β band with ground band. Comparison is made with the X (5) analytical symmetry and the algebraic interacting boson model predictions. Discussion of the 2 n transfer reactions is given. The validity of the multiphonon view of the Kπ=4+ and 22+ bands is also studied.

  14. Resonance methods in quadrupole ion traps

    NASA Astrophysics Data System (ADS)

    Snyder, Dalton T.; Peng, Wen-Ping; Cooks, R. Graham

    2017-01-01

    The quadrupole ion trap is widely used in the chemical physics community for making measurements on dynamical systems, both intramolecular (e.g. ion fragmentation reactions) and intermolecular (e.g. ion/molecule reactions). In this review, we discuss linear and nonlinear resonances in quadrupole ion traps, an understanding of which is critical for operation of these devices and interpretation of the data which they provide. The effect of quadrupole field nonlinearity is addressed, with important implications for promoting fragmentation and achieving unique methods of mass scanning. Methods that depend on ion resonances (i.e. matching an external perturbation with an ion's induced frequency of motion) are discussed, including ion isolation, ion activation, and ion ejection.

  15. Metabonomics study of brain-specific human S100B transgenic mice by using high-performance liquid chromatography coupled with quadrupole time of flight mass spectrometry.

    PubMed

    Liu, Jia Lin; Wang, Hai Lin; Zhang, Lian Feng; Xu, Yan Feng; Deng, Wei; Zhu, Hua; Qin, Chuan

    2011-01-01

    For the purpose of investigating the effects of S100B on the development of Parkinsion's disease (PD), a high-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry (HPLC/MS-ESI-TOF) metabonomic approach was established to study the mesencephalon profiling of brain-specific human S100B transgenic mice. In order to obtain more full-scale chemical information of metabolites, two kinds of separation mechanism, including reversed-phase (RP) column chromatography and hydrophilic interaction liquid chromatography (HILIC) column, were combined to use. Acquired data were subjected to principal component analysis (PCA) to investigate the effects of S100B protein on mice mesencephalon metabolite profiles. Potential biomarkers were screened by using Mass Hunter Prossional Profiller (MPP) and were identified by the accurate mass. Twelve metabolites in mesencephalon of S100B transgenic mice were identified as potential biomarkers, among which, glutamic acid (Glu) detected by RP/MS in negative ionization mode, gamma-aminobutyric acid (GABA) and tryptophan (Trp) detected by HILIC/MS in positive ionization mode, phenylalanine (Phe) and histidine (His) detected by HILIC/MS in negative ionization mode, related to metabolic pathway of neurotransmitters in mice central nervous system. The analytical technique used in this paper was able to detect biochemical changes in mesencephalon of S100B transgenic mice, which may be helpful to understand the action mechanism of S100B protein in the development of PD.

  16. Study of Compton vs. Photoelectric Interactions

    SciTech Connect

    Gronberg, J B; Johnson, S C; Lange, D J; Wright, D M; Beiersdorfer, P

    2004-07-09

    We have studied how often incoming photons interact via a Compton interaction and/or a photoelectric interaction as a function of energy and detector material Results are using a 1m{sup 3} detector, and discrete energy photons from 0.1 MeV up to 10 MeV. Essentially all of the lower energy photons interact at least once in a detector of this size. This is not the case at higher energies. Each detector, photon energy combination was simulated with 2000 photons.

  17. Why study gene-environment interactions?

    USDA-ARS?s Scientific Manuscript database

    PURPOSE OF REVIEW: We examine the reasons for investigating gene-environment interactions and address recent reports evaluating interactions between genes and environmental modulators in relation to cardiovascular disease and its common risk factors. RECENT FINDINGS: Studies focusing on smoking, phy...

  18. Social Interaction: Reality Oriented Social Studies.

    ERIC Educational Resources Information Center

    Price, Tom

    1984-01-01

    Reasons why elementary teachers should use social interaction activities as the core of their social studies program are discussed. The two main vehicles for involving children in guided and purposeful social interaction are the real classroom social system and simulated real-life social activities. (RM)

  19. Interactive Videodisc Case Studies for Medical Education

    PubMed Central

    Harless, William G.; Zier, Marcia A.; Duncan, Robert C.

    1986-01-01

    The TIME Project of the Lister Hill National Center for Biomedical Communications is using interactive videodisc, microprocessor and voice recognition technology to create patient simulations for use in the training of medical students. These interactive case studies embody dramatic, lifelike portrayals of the social and medical conditions of a patient and allow uncued, verbal intervention by the student for independent clinical decisions.

  20. The Large Quadrupole of Water Molecules

    SciTech Connect

    Niu, Shuqiang; Tan, Ming-Liang; Ichiye, Toshhiko

    2011-04-07

    Many quantum mechanical calculations indicate water molecules in the gas and liquid phase have much larger quadrupole moments than any of the common site models of water for computer simulations. Here, comparisons of multipoles from quantum mechanical/molecular mechanical (QM/MM) calculations at the MP2/aug-cc-pVQZ level on a B3LYP/aug-cc-pVQZ level geometry of a waterlike cluster and from various site models show that the increased square planar quadrupole can be attributed to the p-orbital character perpendicular to the molecular plane of the highest occupied molecular orbital as well as a slight shift of negative charge toward the hydrogens. The common site models do not account for the p-orbital type electron density and fitting partial charges of TIP4P- or TIP5P-type models to the QM/MM dipole and quadrupole give unreasonable higher moments. Furthermore, six partial charge sites are necessary to account reasonably for the large quadrupole, and polarizable site models will not remedy the problem unless they account for the p-orbital in the gas phase since the QM calculations show it is present there too. On the other hand, multipole models by definition can use the correct multipoles and the electrostatic potential from the QM/MM multipoles is much closer than that from the site models to the potential from the QM/MM electron density. Finally, Monte Carlo simulations show that increasing the quadrupole in the soft-sticky dipole-quadrupole-octupole multipole model gives radial distribution functions that are in good agreement with experiment

  1. Transverse beam emittance measurement using quadrupole variation at KIRAMS-430

    NASA Astrophysics Data System (ADS)

    An, Dong Hyun; Hahn, Garam; Park, Chawon

    2015-02-01

    In order to produce a 430 MeV/u carbon ion (12 C 6+) beam for medical therapy, the Korea Institute of Radiological & Medical Sciences (KIRAMS) has carried out the development of a superconducting isochronous cyclotron, the KIRAMS-430. At the extraction of the cyclotron, an Energy Selection System (ESS) is located to modulate the fixed beam energy and to drive the ion beam through High Energy Beam Transport (HEBT) into the treatment room. The beam emittance at the ion beamline is to be measured to provide information on designing a beam with high quality. The well-known quadrupole variation method was used to determine the feasibility of measuring the transverse beam emittance. The beam size measured at the beam profile monitor (BPM) is to be utilized and the transformation of beam by transfer matrix is to be applied being taken under various transport condition of varying quadrupole magnetic strength. Two different methods where beam optics are based on the linear matrix formalism and particle tracking with a 3-D magnetic field distribution obtained by using OPERA3D TOSCA, are applied to transport the beam. The fittings for the transformation parameters are used to estimate the transverse emittance and the twiss parameters at the entrance of the quadrupole in the ESS. Including several systematic studies, we conclude that within the uncertainty the estimated emittances are consistent with the ones calculated by using Monte Carlo simulations.

  2. Quadrupole Magnetic Sorting of Porcine Islets of Langerhans

    PubMed Central

    Shenkman, Rustin M.; Chalmers, Jeffrey J.; Hering, Bernhard J.; Kirchhof, Nicole

    2009-01-01

    Islet transplantation is emerging as a treatment option for selected patients with type 1 diabetes. Inconsistent isolation, purification, and recovery of large numbers of high-quality islets remain substantial impediments to progress in the field. Removing islets as soon as they are liberated from the pancreas during digestion and circumventing the need for density gradient purification is likely to result in substantially increased viable islet yields by minimizing exposure to proteolytic enzymes, reactive oxygen intermediates, and mechanical stress associated with centrifugation. This study capitalized on the hypervascularity of islets compared with acinar tissue to explore their preferential enrichment with magnetic beads to enable immediate separation in a magnetic field utilizing a quadrupole magnetic sorting. The results demonstrate that (1) preferential enrichment of porcine islets is achievable, but homogeneous bead distribution within the pancreas is difficult to achieve with current protocols; (2) greater than 70% of islets in the dissociated pancreatic tissue were recovered by quadrupole magnetic sorting, but their purity was low; and (3) infused islets purified by density gradients and subsequently passed through quadrupole magnetic sorting had similar potency as uninfused islets. These results demonstrate proof of concept and define the steps for implementation of this technology in pig and human islet isolation. PMID:19505179

  3. Magnetic Measurement Results of the LCLS Undulator Quadrupoles

    SciTech Connect

    Anderson, Scott; Caban, Keith; Nuhn, Heinz-Dieter; Reese, Ed; Wolf, Zachary; /SLAC

    2011-08-18

    This note details the magnetic measurements and the magnetic center fiducializations that were performed on all of the thirty-six LCLS undulator quadrupoles. Temperature rise, standardization reproducibility, vacuum chamber effects and magnetic center reproducibility measurements are also presented. The Linac Coherent Light Source (LCLS) undulator beam line has 33 girders, each with a LCLS undulator quadrupole which focuses and steers the beam through the beam line. Each quadrupole has main quadrupole coils, as well as separate horizontal and vertical trim coils. Thirty-six quadrupoles, thirty-three installed and three spares were, manufactured for the LCLS undulator system and all were measured to confirm that they met requirement specifications for integrated gradient, harmonics and for magnetic center shifts after current changes. The horizontal and vertical dipole trims of each quadrupole were similarly characterized. Each quadrupole was also fiducialized to its magnetic center. All characterizing measurements on the undulator quads were performed with their mirror plates on and after a standardization of three cycles from -6 to +6 to -6 amps. Since the undulator quadrupoles could be used as a focusing or defocusing magnet depending on their location, all quadrupoles were characterized as focusing and as defocusing quadrupoles. A subset of the undulator quadrupoles were used to verify that the undulator quadrupole design met specifications for temperature rise, standardization reproducibility and magnetic center reproducibility after splitting. The effects of the mirror plates on the undulator quadrupoles were also measured.

  4. The nuclear electric quadrupole moment of copper.

    PubMed

    Santiago, Régis Tadeu; Teodoro, Tiago Quevedo; Haiduke, Roberto Luiz Andrade

    2014-06-21

    The nuclear electric quadrupole moment (NQM) of the (63)Cu nucleus was determined from an indirect approach by combining accurate experimental nuclear quadrupole coupling constants (NQCCs) with relativistic Dirac-Coulomb coupled cluster calculations of the electric field gradient (EFG). The data obtained at the highest level of calculation, DC-CCSD-T, from 14 linear molecules containing the copper atom give rise to an indicated NQM of -198(10) mbarn. Such result slightly deviates from the previously accepted standard value given by the muonic method, -220(15) mbarn, although the error bars are superimposed.

  5. Two Alternate High Gradient Quadrupoles; An Upgraded Tevatron IR and A"Pipe" Design

    SciTech Connect

    McInturff, A.D.; Oort, J.M. van; Scanlan, R.M.

    1995-04-01

    With the U.S. cancellation of the SSC project, the only large approved hadron accelerator project is CERN's LHC. One of the more critical elements in the performance of a collider is the quadrupole lens at the beam collision points. These quadrupoles, usually referred to as the 'insertion quads' normally form a set of triplets around the interaction region. Their focal power directly affects the luminosity available at the crossing point In order to achieve as high a gradient as possible, the CERN design team has proposed a very efficient high gradient quadrupole which is based on a graded four-layer winding structure. At Fermilab's Tevatron, an upgraded two layer winding quadrupole has been in operation since 1989, and has provided a 50% higher gradient than its predecessor. The quadrupole was basically state of the art when it was designed in 1985. Since then however, improvements have been made in cabling, conductor perfonnance, etc. Naturally, operation of a modernized version of this .design can provide higher capabilities. This improved two layer design can serve as an alternative to the more intricate graded four layer design now envisioned for the LHC, provided it can obtain the proposed gradient. A high gradient quadrupole with a 'pipe' layout can be considered as a possible candidate for future large collider insertion regions. It is possible to fine-tune the design to obtain a good field-quality, the conductor is well cooled in case of a large radiation heat load, and the overall structure is smaller than a conventional quadrupole with a comparable field gradient.

  6. Mixed radiation field dosimetry utilizing Nuclear Quadrupole Resonance. Technical progress report

    SciTech Connect

    Hintenlang, D.

    1991-12-31

    This project has proposed to develop a novel dosimetry system that is capable of directly evaluating the chemical/biological damage caused by neutrons, photons, or both in a single measurement. The dosimeter itself will consist of a small volume of biological equivalent material that is probed for radiation damage with Nuclear Quadrupole Resonance (NQR) techniques. NQR has previously been utilized as a sensitive probe of structural and chemical changes at the molecular level for a variety of organic compounds. The biological equivalent materials used in this study will not only have a density similar to tissue (tissue equivalent) but will have the same atomic components as tissue. This is a significant requirement if the important neutron interactions that occur in tissue are to occur in the dosimeter as well. The overall objective of this study is to investigate a methodology to perform accurate mixed-field (neutron and photon) dosimetry for biological systems.

  7. Resident interactions at mealtime: an exploratory study.

    PubMed

    Curle, Leah; Keller, Heather

    2010-09-01

    Social interaction is thought to be important for psychological wellbeing and is necessary for developing relationships between older adults living in facilities. This study seeks to describe the social interaction that occurs amongst tablemates at mealtime in retirement homes, as well those things that influence resident-to-resident interaction. Fourteen lunch time periods were the basis for qualitative participant observation. Two or three researchers collected data in each period, with each observing two tables, resulting in 63 individual table observations at a retirement living facility dining room in a medium-sized city in Southern Ontario. Residents attending mealtime in the dining room were (~ 100). The type, extent and influences on social interactions amongst tablemates were recorded in detailed field notes. Qualitative thematic analysis, using a constant comparison procedure, was used to summarize and make sense of the data. A variety of social interactions occurred amongst tablemates including: making conversation, providing assistance, sharing, humouring, showing appreciation and affection, and rebuffing/ignoring/excluding. Interactions were influenced by tablemate roles, resident characteristics, and the social and physical environment, including staff. Social interactions or lack thereof are important for relationship development and mealtime environment. Describing the types of interaction and what influences them is a first step towards promoting social engagement which can enhance quality of life for residents. Further investigation through interviews with residents on the meaning of mealtime and companionship at meals will build a deeper understanding of the importance and influences on social interaction in this setting.

  8. Recent Studies of the Nuclear Interaction

    NASA Astrophysics Data System (ADS)

    Carlson, J.

    Recent studies of light p-shell nuclei reveal that so-called 'realistic' nuclear interactions, those based on the NN scattering data augmented with plausible models of the three-nucleon interaction, provide a good description or nuclei through A=8. However, significant discrepancies exist, primarily in the energies of neutron rich systems and in the L.S splittings in the spectra of these nuclei. We briefly describe the methods used in these studies, and describe improved models of the three-nucleon interaction.

  9. Quadrupole moments of some doubly-even molibden nuclei and the onset of collectivity

    SciTech Connect

    Turkan, N.; Ibis, I.; Maras, I.

    2012-07-15

    A good description of the quadrupole moments is obtained by investigating {sup 94,96,98,100,102,104,106,108}Mo isotopes in terms of the interacting boson model. After the positiveparity states and electromagnetic-transition rates B(E2) of even-mass Mo nuclei were calculated it was seen that there is a good agreement between the obtained results and some previous experimental data. At the end of the quadrupole moment calculations it was proved that the results agree well with the previous experimental data.

  10. Signature to detect the isovector giant quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Speth, J.; Cha, D.; Klemt, V.; Wambach, J.

    1985-06-01

    We calculate the γ decay from the isoscalar and isovector giant quadrupole resonances in 208Pb into the low-lying spectrum. Whereas the γ decay from the isoscalar giant quadrupole resonance into the first excited 3- state is very small, the corresponding transition from the isovector giant quadrupole resonance is strongly enhanced. According to preliminary calculations, these results hold rather generally for other heavy mass nuclei. We suggest using this property in experimental investigation of the isovector giant quadrupole resonance.

  11. Laser microdissection hyphenated with high performance gel permeation chromatography-charged aerosol detector and ultra performance liquid chromatography-triple quadrupole mass spectrometry for histochemical analysis of polysaccharides in herbal medicine: Ginseng, a case study.

    PubMed

    Chen, Qi-Lei; Chen, Yu-Jie; Zhou, Shan-Shan; Yip, Ka-Man; Xu, Jun; Chen, Hu-Biao; Zhao, Zhong-Zhen

    2017-09-01

    This study establishes a new combinatorial approach for histochemical analysis of polysaccharides in herbal medicines using laser microdissection followed by high performance gel permeation chromatography coupled with charged aerosol detector and ultra-performance liquid chromatography hyphenated with triple quadrupole mass spectrometry. Ginseng was employed as a study model. Tissue-specific qualitative and quantitative characterization of ginseng polysaccharides was performed by determining their molar masses and monosaccharide compositions in three macro-dissected parts (rhizome, main and branched roots) and five micro-dissected tissues (cork, cortex, xylem, phloem and resin canal). The results showed that ginseng "flesh" (xylem, phloem and resin canal) contained more polysaccharides with larger molecular weights and higher ratios of glucose residue, whereas ginseng "skin" (cork and cortex) had fewer polysaccharides with smaller molecular weights and higher ratios of non-glucose constituents (e.g. galacturonic acid, galactose, arabinose and rhamnose). These findings suggested that the polysaccharides of the "flesh" were predominantly starch-like glucans, while those of the "skin" were of a higher proportion of acidic pectins. The revealed histologic distribution and accumulation pattern of ginseng polysaccharides contributes to the scientific understanding of ginseng regarding the biosynthesis and transportation of polysaccharides, medicinal quality evaluation as well as empirical clinical application. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Metabolomics Study of Resina Draconis on Myocardial Ischemia Rats Using Ultraperformance Liquid Chromatography/Quadrupole Time-of-Flight Mass Spectrometry Combined with Pattern Recognition Methods and Metabolic Pathway Analysis

    PubMed Central

    Gu, Haiwei; Song, Yunlong; Dong, Xin; Liu, Aijun; Lou, Ziyang; Fan, Guorong; Chai, Yifeng

    2013-01-01

    Resina draconis (bright red resin isolated from Dracaena cochinchinensis, RD) has been clinically used for treatment of myocardial ischemia (MI) for many years. However, the mechanisms of its pharmacological action on MI are still poorly understood. This study aimed to characterize the plasma metabolic profiles of MI and investigate the mechanisms of RD on MI using ultraperformance liquid chromatography/quadrupole time-of-flight mass spectrometry-based metabolomics combined with pattern recognition methods and metabolic pathway analysis. Twenty metabolite markers characterizing metabolic profile of MI were revealed, which were mainly involved in aminoacyl-tRNA biosynthesis, phenylalanine, tyrosine, and tryptophan biosynthesis, vascular smooth muscle contraction, sphingolipid metabolism, and so forth. After RD treatment, however, levels of seven MI metabolite markers, including phytosphingosine, sphinganine, acetylcarnitine, cGMP, cAMP, L-tyrosine, and L-valine, were turned over, indicating that RD is likely to alleviate MI through regulating the disturbed vascular smooth muscle contraction, sphingolipid metabolism, phenylalanine metabolism, and BCAA metabolism. To our best knowledge, this is the first comprehensive study to investigate the mechanisms of RD for treating MI, from a metabolomics point of view. Our findings are very valuable to gain a better understanding of MI metabolic profiles and provide novel insights for exploring the mechanisms of RD on MI. PMID:23762136

  13. Metabolomics Study of Resina Draconis on Myocardial Ischemia Rats Using Ultraperformance Liquid Chromatography/Quadrupole Time-of-Flight Mass Spectrometry Combined with Pattern Recognition Methods and Metabolic Pathway Analysis.

    PubMed

    Qi, Yunpeng; Gu, Haiwei; Song, Yunlong; Dong, Xin; Liu, Aijun; Lou, Ziyang; Fan, Guorong; Chai, Yifeng

    2013-01-01

    Resina draconis (bright red resin isolated from Dracaena cochinchinensis, RD) has been clinically used for treatment of myocardial ischemia (MI) for many years. However, the mechanisms of its pharmacological action on MI are still poorly understood. This study aimed to characterize the plasma metabolic profiles of MI and investigate the mechanisms of RD on MI using ultraperformance liquid chromatography/quadrupole time-of-flight mass spectrometry-based metabolomics combined with pattern recognition methods and metabolic pathway analysis. Twenty metabolite markers characterizing metabolic profile of MI were revealed, which were mainly involved in aminoacyl-tRNA biosynthesis, phenylalanine, tyrosine, and tryptophan biosynthesis, vascular smooth muscle contraction, sphingolipid metabolism, and so forth. After RD treatment, however, levels of seven MI metabolite markers, including phytosphingosine, sphinganine, acetylcarnitine, cGMP, cAMP, L-tyrosine, and L-valine, were turned over, indicating that RD is likely to alleviate MI through regulating the disturbed vascular smooth muscle contraction, sphingolipid metabolism, phenylalanine metabolism, and BCAA metabolism. To our best knowledge, this is the first comprehensive study to investigate the mechanisms of RD for treating MI, from a metabolomics point of view. Our findings are very valuable to gain a better understanding of MI metabolic profiles and provide novel insights for exploring the mechanisms of RD on MI.

  14. Study of physical interaction mefenamic acid - isonicotinamide

    NASA Astrophysics Data System (ADS)

    Yuyun, Yonelian; Nugrahani, Ilma

    2015-09-01

    Solid-solid interaction in the form of physics and chemistry can occur in a combination of active ingredients with the active ingredient or active ingredients with excipients in a pharmaceutical preparation. Physical interactions can be classified into physical interaction system eutectic, peritectic, and molecular compounds based on the phase diagram of a mixture of two-component systems. The physical interaction between mefenamic acid and isonicotinamide not been reported previously. This study aims to examine the type of interaction of mefenamic acid (MA) with isonicotinamide (INA) and its interaction with the isolation methods by solvent drop grinding as the simplest method and easy to do. PXRD data showed the interaction of MA:INA mixture contained no new peaks, so the indicated MA:INA only form of eutectic interaction. There was founded new endothermic peak for DTA data at 149.5°C (SDG-Ethanol) and 148.4°C (SDG-EtAct). The results of infrared spectroscopy analysis indicated a shift in the NH stretch 3367 cm-1 to 3359 cm-1; and 3185 cm-1 to 3178 cm-1.

  15. Trade-offs in miniature quadrupole designs.

    PubMed

    Boumsellek, S; Ferran, R J

    2001-06-01

    Pressing needs for miniature mass spectrometers became apparent during the last decade in process monitoring and control, space exploration, and environmental screening. Besides the small footprint, common requirements include low cost, low power consumption, field portability, reliability, autonomy, and ease-of-use. Design concepts and construction technologies of miniaturized quadrupole sensors were guided by cost reduction requirements without sacrifice of performance. The first miniature and complete quadrupole mass spectrometer system was introduced as the Micropole sensor. The concept featured a novel technique to assemble and operate multiple miniature quadrupoles in parallel. The short analyzer length offers a significant advantage by enabling direct mass filtering at pressures up in the 10(-2) torr range. High voltages at higher frequencies (10-20 MHz) are required for acceptable mass resolving powers. Additional trade-offs were uncovered in miniature sensors leading to designs optimized for each class of applications. Real time ray tracing of ions injected and filtered in the quadrupole field is used early in the design stage to predict the performance and reliability of the device.

  16. Closed orbit response to quadrupole strength variation

    SciTech Connect

    Wolski, Andrzej; Zimmermann, Frank

    2004-01-20

    We derive two formulae relating the variation in closed orbit in a storage ring to variations in quadrupole strength, neglecting nonlinear and dispersive effects. These formulae correct results previously reported [1,2,3]. We compare the results of the formulae applied to the ATF with simulations using MAD, and consider their application to beam-based alignment.

  17. Determination of polybrominated diphenyl ethers in fish tissues by matrix solid-phase dispersion and gas chromatography coupled to triple quadrupole mass spectrometry: case study on European eel (Anguilla anguilla) from Mediterranean coastal lagoons.

    PubMed

    Labadie, Pierre; Alliot, Fabrice; Bourges, Catherine; Desportes, Annie; Chevreuil, Marc

    2010-08-24

    This paper describes the development and validation of an analytical methodology to determine 28 polybrominated diphenyl ethers (PBDEs) in European eel (Anguilla anguilla) tissues using matrix solid-phase dispersion (MSPD) and gas chromatography coupled to triple quadrupole mass spectrometry (GC-QQQ-MS/MS). A total of 28 PBDEs were targeted, including tri- to deca-brominated congeners. The robustness and effectiveness of the proposed sample preparation procedure was demonstrated in lipid-rich eel tissues. The use of batch MSPD with activated silica gel and H(2)SO(4)-impregnated silica gel, followed by H(2)SO(4) digestion and multilayer cartridge clean-up allowed for complete lipid removal and eliminated matrix effects during GC-QQQ-MS/MS analysis. The average PBDE recoveries from eel muscle samples spiked with PBDEs at two levels were in the range 56.2-119.0%. Precision was satisfactory since relative standard deviations were lower than 19.6%, regardless of spike level, and method quantification limits ranged between 1 and 170 pg g(-1) (wet weight). The method demonstrated its successful application for the analysis of eel samples from two coastal lagoons located on the western French Mediterranean coast. All samples tested positive, but for tri- to hexa-brominated congeners only and total PBDE levels observed in this study were in the range 0.08-1.80 ng g(-1) wet weight. 2010 Elsevier B.V. All rights reserved.

  18. Antiferromagnetic spin fluctuations and unconventional nodeless superconductivity in an iron-based new superconductor (Ca4Al2O(6-y))(Fe2As2): 75As nuclear quadrupole resonance study.

    PubMed

    Kinouchi, H; Mukuda, H; Yashima, M; Kitaoka, Y; Shirage, P M; Eisaki, H; Iyo, A

    2011-07-22

    We report 75As nuclear quadrupole resonance studies on (Ca4Al2O(6-y))(Fe2As2) with T(c) = 27  K. Measurement of nuclear-spin-relaxation rate 1/T1 has revealed a significant development of two-dimensional antiferromagnetic spin fluctuations down to T(c) in association with the smallest As-Fe-As bond angle. Below T(c), the temperature dependence of 1/T1 without any trace of the coherence peak is well accounted for by a nodeless s(±)-wave multiple-gaps model. From the fact that its T(c) is comparable to T(c) = 28  K in the optimally doped LaFeAsO(1-y) in which antiferromagnetic spin fluctuations are not dominant, we remark that antiferromagnetic spin fluctuations are not a unique factor for enhancing T(c) among Fe-based superconductors, but a condition for optimizing superconductivity should be addressed from the lattice structure point of view.

  19. Investigation of the Effect of Rice Wine on the Metabolites of the Main Components of Herbal Medicine in Rat Urine by Ultrahigh-Performance Liquid Chromatography-Quadrupole/Time-of-Flight Mass Spectrometry: A Case Study on Cornus officinalis

    PubMed Central

    Cao, Gang; Cai, Hao; Yue, Xianke; Tu, Sicong; Cai, Baochang; Xu, Zhiwei

    2013-01-01

    Ultrahigh-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UPLC-QTOF/MS) was developed for rapid and sensitive analysis of the effect of rice wine on the metabolites of the main components of herbal medicine in rat urine. Using Cornus officinalis as a model of herbal medicine, the metabolite profiles of crude and processed (steaming the crude drug presteeped in rice wine) Cornus officinalis extracts in rat urine were investigated. The metabolites of Cornus officinalis were identified by using dynamic adjustment of the fragmentor voltage to produce structure-relevant fragment ions. In this work, we identified the parent compounds and metabolites of crude and processed Cornus officinalis in rats. In total, three parent compounds and seventeen new metabolites of Cornus officinalis were found in rats. The contents of the parent compounds and metabolites in vivo varied significantly after intragastric (i.g.) administration of aqueous extracts of crude and processed Cornus officinalis. Data from this study suggests that UPLC-QTOF/MS could be used as a potential tool for uncovering the effects of excipients found in the metabolites of the main components of herbal medicine, in vivo, to predict and discover the processing mechanisms of herbal medicine. PMID:23737825

  20. The nature of collision-induced dissociation processes of doubly protonated peptides: comparative study for the future use of matrix-assisted laser desorption/ionization on a hybrid quadrupole time-of-flight mass spectrometer in proteomics.

    PubMed

    Cramer, R; Corless, S

    2001-01-01

    Comparative MS/MS studies of singly and doubly charged electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) precursor peptide ions are described. The spectra from these experiments have been evaluated with particular emphasis on the data quality for subsequent data processing and protein/amino acid sequence identification. It is shown that, once peptide ions are formed by ESI or MALDI, their charge state, as well as the collision energy, is the main parameter determining the quality of collision-induced dissociation (CID) MS/MS fragmentation spectra of a given peptide. CID-MS/MS spectra of singly charged peptides obtained on a hybrid quadrupole orthogonal time-of-flight mass spectrometer resemble very closely spectra obtained by matrix-assisted laser desorption/ionization post-source decay time-of-flight mass spectrometry (MALDI-PSD-TOFMS). On the other hand, comparison of CID-MS/MS spectra of either singly or doubly charged ion species shows no dependence on whether ions have been formed by ESI or MALDI. This observation confirms that, at the time of precursor ion selection, further mass analysis is effectively decoupled from the desorption/ionization event. Since MALDI ions are predominantly formed as singly charged species and ESI ions as doubly charged, the associated difference in the spectral quality of MS/MS spectra as described here imposes direct consequences on data processing, database searching using ion fragmentation data, and de novo sequencing when ionization techniques are changed.

  1. Protein-Inhibitor Interaction Studies Using NMR

    PubMed Central

    Ishima, Rieko

    2015-01-01

    Solution-state NMR has been widely applied to determine the three-dimensional structure, dynamics, and molecular interactions of proteins. The designs of experiments used in protein NMR differ from those used for small-molecule NMR, primarily because the information available prior to an experiment, such as molecular mass and knowledge of the primary structure, is unique for proteins compared to small molecules. In this review article, protein NMR for structural biology is introduced with comparisons to small-molecule NMR, such as descriptions of labeling strategies and the effects of molecular dynamics on relaxation. Next, applications for protein NMR are reviewed, especially practical aspects for protein-observed ligand-protein interaction studies. Overall, the following topics are described: (1) characteristics of protein NMR, (2) methods to detect protein-ligand interactions by NMR, and (3) practical aspects of carrying out protein-observed inhibitor-protein interaction studies. PMID:26361636

  2. Space Operations Center: Shuttle interaction study

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The implication of using the Shuttle with the Space Operation Center (SOC), including constraints that the Shuttle will place upon the SOC design. The study identifies the considerations involved in the use of the Shuttle as a part of the SOC concept, and also identifies the constraints to the SOC imposed by the Shuttle in its interactions with the SOC, and on the design or technical solutions which allow satisfactory accomplishment of the interactions.

  3. Interaction of melittin with mixed phospholipid membranes composed of dimyristoylphosphatidylcholine and dimyristoylphosphatidylserine studied by deuterium NMR

    SciTech Connect

    Dempsey, C.; Bitbol, M.; Watts, A. )

    1989-08-08

    The interaction of bee venom melittin with mixed phospholipid bilayers composed of dimyristoylphosphatidylcholine deuterated in the {alpha}- and {beta}-methylenes of the choline head group (DMPC-d{sub 4}) and dimyristoylphosphatidylserine deuterated in the {alpha}-methylene and {beta}-CH positions of the serine head group (DMPS-d{sub 3}) was studied in ternary mixtures by using deuterium NMR spectroscopy. The changes in the deuterium quadrupole splittings of the head-group deuteriomethylenes of DMPC-d{sub 4} induced by DMPS in binary mixtures were systematically reversed by increasing concentrations of melittin, so that at a melittin concentration of 4 mol % relative to total lipid the deuterium NMR spectrum from DMPC-d{sub 4} in the ternary mixture was similar to the spectrum from pure DMPC-d{sub 4} bilayers. The absence of deuterium NMR signals arising from melittin-bound DMPS in ternary mixtures containing DMPS-d{sub 3} indicates that the reversal by melittin of the effects of DMPS on the quadrupole splittings of DMPC-d{sub 4} results from the response of the choline head group to the net surface charge rather than from phase separation of melittin-DMPS complexes. The similarity in the effects of the two cationic but otherwise dissimilar peptides indicates that the DMPS head group responds to the surface charge resulting from the presence in the bilayer of charged amphiphiles, in a manner analogous to the response of the choline head group of phosphatidylcholine to the bilayer surface charge. The presence of DMPS greatly stabilized DMPC bilayers with respect to melittin-induced micellization, indicating that the latter effect of melittin may not be important for the hemolytic activity of the peptide.

  4. Nuclear Quadrupole Resonance Investigation of Spin Dynamics in the Praseodymium Trihalides Praseodymium Trichloride and Praseodymium Tribromide.

    NASA Astrophysics Data System (ADS)

    Su, Sunyu

    The spin dynamics of PrCl_3 and PrBr_3 have been studied in the temperature range from 124mK to 297K using Nuclear Quadrupole Resonance (NQR) techniques. In the low temperature regime, the Pr ions are in the ground state, and the dynamical properties of PrX_3 (X = Cl,Br) are well described by a 1D XY model. The data have been shown to be in agreement with the predictions of a relaxation theory for a magnetic interaction based on a rigorous treatment of the longitudinal dynamical correlation function < S_sp{z}{m}(t)S_sp {z}{n}(t)> of the electronic pseudo-spins S^{m} associated with the crystalline electric field ground state. The fits to the data have yielded reasonable values for the hyperfine interaction parameters A and exchange integrals J/k_{B}. The dynamical properties of the PrX_3 compounds depart from the 1D model as the temperature increases. The spin lattice relaxation rates display unusual temperature dependences in the high temperature regime. These temperature dependences have been qualitatively accounted for by considering the effect of populating the excited states of the crystal electric field. The theory of NQR mixed spin echoes in solids has been established using the interaction representation formalism. The NQR mixed spin echoes theory has been applied to the study of the spin interactions in PrBr_3 . It has been shown that the second moments due to quadrupole interaction M_sp{2} {q}, magnetic dipole-dipole interactions between like spins M_sp{2}{II } and magnetic dipole-dipole interactions between unlike spins M_sp{2}{IS}(Br,Pr ^{3+}),M_sp{2}{IS }(^{79}Br,^{81}Br ) can be simultaneously determined. NQR spectra have been obtained for both praseodymium trihalides. The low temperature spectrum of PrCl _3 has provided strong support to the earlier results. In addition, the present investigation of the NQR spectrum has resulted in a better estimate of the magnitude of dimerization in PrCl_3. The PrBr_3 low temperature NQR spectrum has revealed

  5. Electron-induced dissociation of peptides in a triple quadrupole mass spectrometer retrofitted with an electromagnetostatic cell.

    PubMed

    Voinov, Valery G; Bennett, Samuel E; Barofsky, Douglas F

    2015-05-01

    Dissociation of peptides induced by interaction with (free) electrons (electron-induced dissociation, EID) at electron energies ranging from near 0 to >30 eV was carried out using a radio-frequency-free electromagnetostatic (EMS) cell retrofitted into a triple quadrupole mass spectrometer. The product-ion mass spectra exhibited EID originating from electronically excited even-electron precursor ions, reduced radical cations formed by capture of low-energy electrons, and oxidized radical cations produced by interaction with high-energy electrons. The spectra demonstrate, within the limits of the triple quadrupole's resolving power, that high-energy EID product-ion spectra produced with an EMS cell exhibit essentially the same qualitative structural information, i.e., amino acid side-chain (SC) losses and backbone cleavages, as observed in high-energy EID spectra produced with a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer. The levels of fragmentation efficiency evident in the product-ion spectra recorded in this study, as was the case for those recorded in earlier studies with FT ICR mass spectrometers, is currently at the margin of analytical utility. Given that this shortcoming can be remedied, EMS cells incorporated into QqQ or QqTOF mass spectrometers could make tandem high-energy EID mass spectrometry more widely accessible for analysis of peptides, small singly charged molecules, pharmaceuticals, and clinical samples.

  6. Electron-Induced Dissociation of Peptides in a Triple Quadrupole Mass Spectrometer Retrofitted with an Electromagnetostatic Cell

    NASA Astrophysics Data System (ADS)

    Voinov, Valery G.; Bennett, Samuel E.; Barofsky, Douglas F.

    2015-05-01

    Dissociation of peptides induced by interaction with (free) electrons (electron-induced dissociation, EID) at electron energies ranging from near 0 to >30 eV was carried out using a radio-frequency-free electromagnetostatic (EMS) cell retrofitted into a triple quadrupole mass spectrometer. The product-ion mass spectra exhibited EID originating from electronically excited even-electron precursor ions, reduced radical cations formed by capture of low-energy electrons, and oxidized radical cations produced by interaction with high-energy electrons. The spectra demonstrate, within the limits of the triple quadrupole's resolving power, that high-energy EID product-ion spectra produced with an EMS cell exhibit essentially the same qualitative structural information, i.e., amino acid side-chain (SC) losses and backbone cleavages, as observed in high-energy EID spectra produced with a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer. The levels of fragmentation efficiency evident in the product-ion spectra recorded in this study, as was the case for those recorded in earlier studies with FT ICR mass spectrometers, is currently at the margin of analytical utility. Given that this shortcoming can be remedied, EMS cells incorporated into QqQ or QqTOF mass spectrometers could make tandem high-energy EID mass spectrometry more widely accessible for analysis of peptides, small singly charged molecules, pharmaceuticals, and clinical samples.

  7. SPIV study of two interactive fire whirls

    NASA Astrophysics Data System (ADS)

    Hartl, Katherine; Smits, Alexander

    2015-11-01

    Fire whirls are buoyancy-driven standing vortex structures that often form in forest fires. Capable of lifting and ejecting flaming debris, fire whirls can hasten the spread of fire lines and start fires in new places. Here we study the interaction of two jets in an externally applied circulation as an introduction to the study of two interacting fire whirls. To study this interaction we use two burner flames supplied with DME and induce swirl by entraining air through a split cylinder that surrounds both burners. Three components of velocity are measured using Stereo Particle Image Velocimetry both inside and outside the fire whirl core, at the base, midsection, and above the top of the fire whirls. The effects on the height and circulation on the distance between the burners, the rate of fuel supplied to the burners, and the gap size, are examined.

  8. The quadrupole moments of Cd and Zn isotopes - an apology

    NASA Astrophysics Data System (ADS)

    Haas, H.; Barbosa, M. B.; Correia, J. G.

    2016-12-01

    In 2010 we presented an update of the nuclear quadrupole moments (Q) for the Cd and Zn isotopes, based essentially on straightforward density functional (DF) calculations (H. Haas and J.G. Correia, Hyperfine Interact 198, 133-137 (2010)). It has been apparent for some years that the standard DF procedure obviously fails, however, to reproduce the known electric-field gradient (EFG) for various systems, typical cases being Cu2O, As and Sb, and the solid halogens. Recently a cure for this deficiency has been found in the hybrid DF technique. This method is now applied to solid Cd and Zn, and the resultant quadrupole moments are about 15 % smaller than in our earlier report. Also nuclear systematics, using the recently revised values of Q for the long-lived 11/2 isomers in111Cd to129Cd, together with earlier PAD data for107,109Cd, leads to the same conclusion. In addition, EFG calculations for the cadmium dimethyl molecule further support the new values: Q(111Cd, 5/2+) = .683(20) b, Q(67Zn, gs) = .132(5) b. This implies, that the value for the atomic EFG in the 3it {P}1 state of Zn must be revised, as it has been for Cd.

  9. Microwave spectrum, molecular structure, and quadrupole coupling of vinyl chloroformate

    NASA Astrophysics Data System (ADS)

    Bimler, Jonathan; Broadbent, Stacy; Utzat, Karissa A.; Bohn, Robert K.; Restrepo, Albeiro; Harvey Michels, H.; True, Nancy S.

    2012-09-01

    Vinyl chloroformate is confirmed to have the planar structure reported in an earlier study [1]. Our study uses much higher resolution microwave rotational spectra and ab initio calculations have been extended to a higher level. Naturally abundant isotopologs with single substitution of 37Cl, 13C, and 18O isotopes have also been measured and a substitution structure obtained. The quadrupole coupling constants of the 35Cl and 37Cl isotopologs have been determined. The potential energy profiles of internal rotation about the Odbnd Csbnd Osbnd C and Csbnd Osbnd Cdbnd C dihedral angles have been calculated.

  10. Interdisciplinary Studies of Magma-Tectonic Interactions

    NASA Astrophysics Data System (ADS)

    LaFemina, Peter; Stix, John; Saballos, Armando

    2013-08-01

    The Pan-American Advanced Studies Institute (PASI) Magma-Tectonic Interactions in the Americas brought together researchers, postdoctoral fellows, and graduate students from every country in the Americas with active volcanoes and one participant from Iceland. Lecturers presented the latest geochemical and geophysical approaches to studying magma-tectonic interactions. Participants were introduced to the tectonics and volcanism of Nicaragua through a daylong field trip and given opportunities to collect and analyze their own data, including seismic, geodetic, and geochemical data, at the Cerro Negro volcano.

  11. Permanent-magnet quadrupoles in RFQ Linacs

    SciTech Connect

    Lysenko, W.P.; Wang, T.F.

    1985-10-01

    We investigated the possibility of increasing the current-carrying capability of radio-frequency quadrupole (RFQ) linear accelerators by adding permanentmagnet quadrupole (PMQ) focusing to the existing transverse focusing provided by the rf electric field. Increased transverse focusing would also allow shortening RFQ linacs by permitting a larger accelerating gradient, which is normally accompanied by an undesirable increased transverse rf defocusing effect. We found that PMQs were not helpful in increasing the transverse focusing strength in an RFQ. This conclusion was reached after some particle tracing simulations and some analytical calculations. In our parameter regime, the addition of the magnets increases the betatron frequency but does not result in improved focusing because the increased flutter more than offsets the gain from the increased betatron frequency.

  12. Radio frequency quadrupole resonator for linear accelerator

    DOEpatents

    Moretti, Alfred

    1985-01-01

    An RFQ resonator for a linear accelerator having a reduced level of interfering modes and producing a quadrupole mode for focusing, bunching and accelerating beams of heavy charged particles, with the construction being characterized by four elongated resonating rods within a cylinder with the rods being alternately shorted and open electrically to the shell at common ends of the rods to provide an LC parallel resonant circuit when activated by a magnetic field transverse to the longitudinal axis.

  13. Electrostatic quadrupole DC accelerators for BNCT applications

    SciTech Connect

    Kwan, J.W.; Anderson, O.A.; Reginato, L.L.; Vella, M.C.; Yu, S.S.

    1994-04-01

    A dc electrostatic quadrupole (ESQ) accelerator is capable of producing a 2.5 MeV, 100 mA proton beam for the purpose of generating neutrons for Boron Neutron Capture Therapy. The ESQ accelerator is better than the conventional aperture column in high beam current application due to the presence of stronger transverse field for beam focusing and for suppressing secondary electrons. The major challenge in this type of accelerator is in developing the proper power supply system.

  14. Muon cooling in a quadrupole magnet channel

    SciTech Connect

    Neuffer, David; Poklonskiy, A.; /Michigan State U.

    2007-10-01

    As discussed before,[1] a cooling channel using quadrupole magnets in a FODO transport channel can be used for initial cooling of muons. In the present note we discuss this possibility of a FODO focusing channel for cooling, and we present ICOOL simulations of muon cooling within a FODO channel. We explore a 1.5m cell-length cooling channel that could be used for the initial transverse cooling stage of a muon collider or neutrino factory.

  15. 15 T And Beyond - Dipoles and Quadrupoles

    SciTech Connect

    Sabbi, GianLuca

    2008-05-19

    Starting with the invention of the cyclotron by Lawrence, accelerator-based experiments have been the primary source of new discoveries in particle physics. In order to progress toward higher energy and luminosity, higher field magnets are required. R&D programs are underway to take advantage of new developments in superconducting materials, achieve better efficiency and simplify magnet fabrication while preserving accelerator-class field quality. A review of recent progress on high field dipole and quadrupole magnets is presented.

  16. Quadrupole transitions revealed by Borrmann spectroscopy.

    PubMed

    Pettifer, Robert F; Collins, Stephen P; Laundy, David

    2008-07-10

    The Borrmann effect-a dramatic increase in transparency to X-ray beams-is observed when X-rays satisfying Bragg's law diffract through a perfect crystal. The minimization of absorption seen in the Borrmann effect has been explained by noting that the electric field of the X-ray beam approaches zero amplitude at the crystal planes, thus avoiding the atoms. Here we show experimentally that under conditions of absorption suppression, the weaker electric quadrupole absorption transitions are effectively enhanced to such a degree that they can dominate the absorption spectrum. This effect can be exploited as an atomic spectroscopy technique; we show that quadrupole transitions give rise to additional structure at the L(1), L(2) and L(3) absorption edges of gadolinium in gadolinium gallium garnet, which mark the onset of excitations from 2s, 2p(1/2) and 2p(3/2) atomic core levels, respectively. Although the Borrmann effect served to underpin the development of the theory of X-ray diffraction, this is potentially the most important experimental application of the phenomenon since its first observation seven decades ago. Identifying quadrupole features in X-ray absorption spectroscopy is central to the interpretation of 'pre-edge' spectra, which are often taken to be indicators of local symmetry, valence and atomic environment. Quadrupolar absorption isolates states of different symmetries to that of the dominant dipole spectrum, and typically reveals orbitals that dominate the electronic ground-state properties of lanthanides and 3d transition metals, including magnetism. Results from our Borrmann spectroscopy technique feed into contemporary discussions regarding resonant X-ray diffraction and the nature of pre-edge lines identified by inelastic X-ray scattering. Furthermore, because the Borrmann effect has been observed in photonic materials, it seems likely that the quadrupole enhancement reported here will play an important role in modern optics.

  17. Nb{sub 3}Sn ARC quadrupole magnets for VLHC

    SciTech Connect

    Vadim V. Kashikhin and Alexander V. Zlobin

    2001-07-30

    Superconducting quadrupoles with a field gradient of 400-450 T/m for a future Very Large Hadron Collider (VLHC) are being studied at Fermilab. To reach the target field gradient in a 40-50 mm aperture, Nb{sub 3}Sn superconductor is used at an operating temperature of 4.2 K. Two cases with different magnet functions, beam separation distances and coil arrangements have been analyzed and optimized in order to provide the required field quality and magnet parameters.

  18. Design of an rf quadrupole for Landau damping

    NASA Astrophysics Data System (ADS)

    Papke, K.; Grudiev, A.

    2017-08-01

    The recently proposed superconducting quadrupole resonator for Landau damping in accelerators is subjected to a detailed design study. The optimization process of two different cavity types is presented following the requirements of the High Luminosity Large Hadron Collider (HL-LHC) with the main focus on quadrupolar strength, surface peak fields, and impedance. The lower order and higher order mode (LOM and HOM) spectrum of the optimized cavities is investigated and different approaches for their damping are proposed. On the basis of an example the first two higher order multipole errors are calculated. Likewise on this example the required rf power and optimal external quality factor for the input coupler is derived.

  19. Optimized Superconducting Quadrupole Arrays for Multiple Beam Transport

    SciTech Connect

    Meinke, Rainer, B.; Goodzeit, Carl, L.; Ball, Millicent, J.

    2005-09-20

    This research project advanced the development of reliable, cost-effective arrays of superconducting quadrupole magnets for use in multi-beam inertial fusion accelerators. The field in each array cell must be identical and meet stringent requirements for field quality and strength. An optimized compact array design using flat double-layer pancake coils was developed. Analytical studies of edge termination methods showed that it is feasible to meet the requirements for field uniformity in all cells and elimination of stray external field in several ways: active methods that involve placement of field compensating coils on the periphery of the array or a passive method that involves use of iron shielding.

  20. An Oral Contraceptive Drug Interaction Study

    ERIC Educational Resources Information Center

    Bradstreet, Thomas E.; Panebianco, Deborah L.

    2004-01-01

    This article focuses on a two treatment, two period, two treatment sequence crossover drug interaction study of a new drug and a standard oral contraceptive therapy. Both normal theory and distribution-free statistical analyses are provided along with a notable amount of graphical insight into the dataset. For one of the variables, the decision on…

  1. NACASETAC BAY: AN INTERACTIVE CASE STUDY

    EPA Science Inventory

    This interactive case study or "game" was created to provide a "hands on" experience in the application of a weight of evidence approach to sediment assessment. The game proceeds in two phases. In each phase the players work together as a group. A scenario is presented, and the g...

  2. An Oral Contraceptive Drug Interaction Study

    ERIC Educational Resources Information Center

    Bradstreet, Thomas E.; Panebianco, Deborah L.

    2004-01-01

    This article focuses on a two treatment, two period, two treatment sequence crossover drug interaction study of a new drug and a standard oral contraceptive therapy. Both normal theory and distribution-free statistical analyses are provided along with a notable amount of graphical insight into the dataset. For one of the variables, the decision on…

  3. NACASETAC BAY: AN INTERACTIVE CASE STUDY

    EPA Science Inventory

    This interactive case study or "game" was created to provide a "hands on" experience in the application of a weight of evidence approach to sediment assessment. The game proceeds in two phases. In each phase the players work together as a group. A scenario is presented, and the g...

  4. Design, development, and acceleration trials of radio-frequency quadrupole.

    PubMed

    Rao, S V L S; Jain, Piyush; Pande, Rajni; Roy, Shweta; Mathew, Jose V; Kumar, Rajesh; Pande, Manjiri; Krishnagopal, S; Gupta, S K; Singh, P

    2014-04-01

    A deuteron radio frequency quadrupole (RFQ) accelerator has been designed, fabricated, and tested at BARC, which will be used for neutron generation. The RFQ operates at a frequency of 350 MHz and needs an inter-vane voltage of 44 kV to accelerate the deuteron beam to 400 keV within a length of 1.03 m. The error analysis shows that the offset of two opposite vanes in the same direction by 100 μm leads to a change in resonant frequency by 1.3 MHz and a significant change of fields in the quadrants (∼±40% with respect to average field). From the 3D analysis, we have observed that the unwanted dipole mode frequencies are very near to the quadrupole mode frequency which will make structure sensitive to the perturbations. In order to move the dipole modes away from the quadrupole modes, we have used the dipole stabilizer rods. The 5 wire transmission line theory was used to study the perturbative analysis of the RFQ and based on this a computer program has been written to tune the cavity to get required field distribution. Based on these studies, a 1.03 m long RFQ made of OFE copper has been fabricated and tested. Even though the RFQ was designed for deuteron (D(+)) beam, we tested it by accelerating both the proton (H(+)) and D(+) beams. The RFQ was operated in pulsed mode and accelerated both H(+) and D(+) beams to designed values of 200 and 400 keV, respectively. The measured parameters are in good agreement with the designed values validating our simulations and fabrication processes. In this paper, simulations, RF measurements, and beam commissioning results are presented.

  5. Design, development, and acceleration trials of radio-frequency quadrupole

    SciTech Connect

    Rao, S. V. L. S. Jain, Piyush; Pande, Rajni; Roy, Shweta; Mathew, Jose V.; Kumar, Rajesh; Pande, Manjiri; Krishnagopal, S.; Gupta, S. K.; Singh, P.

    2014-04-15

    A deuteron radio frequency quadrupole (RFQ) accelerator has been designed, fabricated, and tested at BARC, which will be used for neutron generation. The RFQ operates at a frequency of 350 MHz and needs an inter-vane voltage of 44 kV to accelerate the deuteron beam to 400 keV within a length of 1.03 m. The error analysis shows that the offset of two opposite vanes in the same direction by 100 μm leads to a change in resonant frequency by 1.3 MHz and a significant change of fields in the quadrants (∼±40% with respect to average field). From the 3D analysis, we have observed that the unwanted dipole mode frequencies are very near to the quadrupole mode frequency which will make structure sensitive to the perturbations. In order to move the dipole modes away from the quadrupole modes, we have used the dipole stabilizer rods. The 5 wire transmission line theory was used to study the perturbative analysis of the RFQ and based on this a computer program has been written to tune the cavity to get required field distribution. Based on these studies, a 1.03 m long RFQ made of OFE copper has been fabricated and tested. Even though the RFQ was designed for deuteron (D{sup +}) beam, we tested it by accelerating both the proton (H{sup +}) and D{sup +} beams. The RFQ was operated in pulsed mode and accelerated both H{sup +} and D{sup +} beams to designed values of 200 and 400 keV, respectively. The measured parameters are in good agreement with the designed values validating our simulations and fabrication processes. In this paper, simulations, RF measurements, and beam commissioning results are presented.

  6. A Study of Multiplicities in Hadronic Interactions

    SciTech Connect

    Estrada Tristan, Nora Patricia; /San Luis Potosi U.

    2006-02-01

    Using data from the SELEX (Fermilab E781) experiment obtained with a minimum-bias trigger, we study multiplicity and angular distributions of secondary particles produced in interactions in the experimental targets. We observe interactions of {Sigma}{sup -}, proton, {pi}{sup -}, and {pi}{sup +}, at beam momenta between 250 GeV/c and 650 GeV/c, in copper, polyethylene, graphite, and beryllium targets. We show that the multiplicity and angular distributions for meson and baryon beams at the same momentum are identical. We also show that the mean multiplicity increases with beam momentum, and presents only small variations with the target material.

  7. Systems interaction study of a Westinghouse PWR

    SciTech Connect

    Youngblood, R.; Hanan, N.; Fitzpatrick, R.; Xue, D.; Bozoki, G.; Fresco, A.; Papazoglou, I.A.

    1985-01-01

    This paper presents methods and findings of a systems interaction study of Indian Point 3. The study was carried out in support of the resolution of Unresolved Safety Issue A-17 on Systems Interactions. Fault tree methods were employed. Among the study's findings is a single active failure in the low pressure injection function; this discovery led to a plant modification. In addition to providing support to the staff in resolving USI A-17, the project discovered an important new class of failure modes which led the utility to implement a hardware modification. The scope of the project is indicated, key features of the method are highlighted findings are discussed, and comments are offered on the usefulness of this type of, principal study. 9 refs., 1 fig., 1 tab.

  8. Metabolism studies of diclofenac and clofibric acid in activated sludge bioreactors using liquid chromatography with quadrupole - time-of-flight mass spectrometry

    NASA Astrophysics Data System (ADS)

    Kosjek, Tina; Heath, Ester; Pérez, Sandra; Petrović, Mira; Barceló, Damia

    2009-06-01

    SummaryTwo environmentally relevant pharmaceuticals, the non-steroidal antiinflammatory drug, diclofenac and the pharmacologically active metabolite of several serum triglyceride-lowering pharmaceuticals, clofibric acid, were subjected to microbiological transformation in activated sludge bioreactors, and the production of breakdown products was studied. For separation, detection and identification of diclofenac's metabolites a UPLC-(+)ESI-QqToF-MS was employed, which enabled the detection of seven transformation products of diclofenac, all including the diagnostic fragment ion at m/z 214. The chemical structure of one metabolite was proposed, which was produced by dehydratation and lactame formation. Further investigations revealed additional two metabolites, which were isomeric structures with an elemental composition C 13H 10NCl 2; however, their chemical structures were not completely resolved. In addition, another biodegradation product showed an abundant fragment ion at m/z 295, the elemental composition of which was confirmed with a high degree of certainty as C 14H 11NO 2Cl 2. The biodegradation of clofibric acid revealed one metabolite in the (-)ESI-QqToF chromatogram, 4-chlorophenol, which is known to exhibit a higher toxicity than the parent compound. This study confirms that further research is needed on the formation of stable metabolites both during wastewater treatment and in the environment. It also highlights the need for parallel toxicity testing. In addition, this study suggests that more needs to be known about the environmental fate of pharmaceuticals so that we are able to provide a comprehensive risk assessment.

  9. Point dipole and quadrupole scattering approximation to collectively responding resonator systems

    NASA Astrophysics Data System (ADS)

    Watson, Derek W.; Jenkins, Stewart D.; Ruostekoski, Janne

    2017-07-01

    We develop a theoretical formalism for collectively responding point scatterers where the radiating electromagnetic fields from each emitter are considered in the electric dipole, magnetic dipole, and electric quadrupole approximation. The contributions of the electric quadrupole moment to electromagnetically-mediated interactions between the scatterers are derived in detail for a system where each scatterer represents a linear R L C circuit resonator, representing common metamaterial resonators in radiofrequency, microwave, and optical regimes. The resulting theory includes a closed set of equations for an ensemble of discrete resonators that are radiatively coupled to each other by propagating electromagnetic fields, incorporating potentially strong interactions and recurrent scattering processes. The effective model is illustrated and tested for examples of pairs of interacting point electric dipoles, where each pair can be qualitatively replaced by a model point emitter with different multipole radiation moments.

  10. Electrons in a positive-ion beam with solenoid or quadrupole magnetic transport

    SciTech Connect

    Molvik, A.W.; Kireeff Covo, M.; Cohen, R.; Coleman, J.; Sharp, W.; Bieniosek, F.; Friedman, A.; Roy, P.K.; Seidl, P.; Lund, S.M.; Faltens, A.; Vay, J.L.; Prost, L.

    2007-06-04

    The High Current Experiment (HCX) is used to study beam transport and accumulation of electrons in quadrupole magnets and the Neutralized Drift-Compression Experiment (NDCX) to study beam transport through and accumulation of electrons in magnetic solenoids. We find that both clearing and suppressor electrodes perform as intended, enabling electron cloud densities to be minimized. Then, the measured beam envelopes in both quadrupoles and solenoids agree with simulations, indicating that theoretical beam current transport limits are reliable, in the absence of electrons. At the other extreme, reversing electrode biases with the solenoid transport effectively traps electrons; or, in quadrupole magnets, grounding the suppressor electrode allows electron emission from the end wall to flood the beam, in both cases producing significant degradation in the beam.

  11. Electrons in a Positive-Ion Beam with Solenoid or Quadrupole Magnet Transport

    SciTech Connect

    Molvik, A W; Cohen, R H; Friedman, A; Covo, M K; Lund, S M; Sharp, W M; Seidl, P A; Bieniosek, F M; Coleman, J E; Faltens, A; Roy, P K; Vay, J L; Prost, L

    2007-06-01

    The High Current Experiment (HCX) is used to study beam transport and accumulation of electrons in quadrupole magnets and the Neutralized Drift-Compression Experiment (NDCX) to study beam transport through and accumulation of electrons in magnetic solenoids. We find that both clearing and suppressor electrodes perform as intended, enabling electron cloud densities to be minimized. Then, the measured beam envelopes in both quadrupoles and solenoids agree with simulations, indicating that theoretical beam current transport limits are reliable, in the absence of electrons. At the other extreme, reversing electrode biases with the solenoid transport effectively traps electrons; or, in quadrupole magnets, grounding the suppressor electrode allows electron emission from the end wall to flood the beam, in both cases producing significant degradation in the beam.

  12. Multiparticle losses in a linear quadrupole Paul trap

    NASA Astrophysics Data System (ADS)

    Semerikov, I. A.; Zalivako, I. V.; Shpakovskii, T. V.; Borisenko, A. S.; Khabarova, K. Yu.; Sorokin, V. N.; Kolachevsky, N. N.

    2016-10-01

    A linear quadrupole Paul trap is fabricated for capturing magnesium and aluminium ions. An experimental cycle performed has demonstrated ion capture and holding in a trap with an average ion lifetime of 1.7 {\\text{s}}. Modelling of ion dynamics in the trap shows that the main mechanism responsible for losses of hot ions is multiparticle interaction, which results in that a kinetic energy of some ions increases and they leave the trapping zone. This mechanism is completely suppressed if ions are cooled. Another mechanism is the charge exchange; however, it is not substantial at a high average energy of ions produced in the result of an electron impact. Parameters of the trap allow one to perform precision spectroscopic measurements and to control ion quantum states.

  13. Microscopic analysis of quadrupole-octupole shape evolution

    NASA Astrophysics Data System (ADS)

    Nomura, Kosuke

    2015-05-01

    We analyze the quadrupole-octupole collective states based on the microscopic energy density functional framework. By mapping the deformation constrained self-consistent axially symmetric mean-field energy surfaces onto the equivalent Hamiltonian of the sdf interacting boson model (IBM), that is, onto the energy expectation value in the boson coherent state, the Hamiltonian parameters are determined. The resulting IBM Hamiltonian is used to calculate excitation spectra and transition rates for the positive- and negative-parity collective states in large sets of nuclei characteristic for octupole deformation and collectivity. Consistently with the empirical trend, the microscopic calculation based on the systematics of β2 - β3 energy maps, the resulting low-lying negative-parity bands and transition rates show evidence of a shape transition between stable octupole deformation and octupole vibrations characteristic for β3-soft potentials.

  14. Covariant spectator theory of np scattering: Deuteron quadrupole moment

    SciTech Connect

    Gross, Franz

    2015-01-26

    The deuteron quadrupole moment is calculated using two CST model wave functions obtained from the 2007 high precision fits to np scattering data. Included in the calculation are a new class of isoscalar np interaction currents automatically generated by the nuclear force model used in these fits. The prediction for model WJC-1, with larger relativistic P-state components, is 2.5% smaller that the experiential result, in common with the inability of models prior to 2014 to predict this important quantity. However, model WJC-2, with very small P-state components, gives agreement to better than 1%, similar to the results obtained recently from XEFT predictions to order N3LO.

  15. Covariant spectator theory of np scattering: Deuteron quadrupole moment

    DOE PAGES

    Gross, Franz

    2015-01-26

    The deuteron quadrupole moment is calculated using two CST model wave functions obtained from the 2007 high precision fits to np scattering data. Included in the calculation are a new class of isoscalar np interaction currents automatically generated by the nuclear force model used in these fits. The prediction for model WJC-1, with larger relativistic P-state components, is 2.5% smaller that the experiential result, in common with the inability of models prior to 2014 to predict this important quantity. However, model WJC-2, with very small P-state components, gives agreement to better than 1%, similar to the results obtained recently frommore » XEFT predictions to order N3LO.« less

  16. A Cryogenic test stand for LHC quadrupole magnets

    SciTech Connect

    R. J. Rabehl et al.

    2004-03-09

    A new test stand for testing LHC interaction region (IR) quadrupole magnets at the Fermilab Magnet Test Facility has been designed and operated. The test stand uses a double bath system with a lambda plate to provide the magnet with a stagnant bath of pressurized He II at 1.9 K and 0.13 MPa. A cryostated magnet 0.91 m in diameter and up to 13 m in length can be accommodated. This paper describes the system design and operation. Issues related to both 4.5 K and 1.9 K operations and magnet quenching are highlighted. An overview of the data acquisition and cryogenics controls systems is also included.

  17. Quadrupole collectivity in neutron-rich Fe and Cr isotopes.

    PubMed

    Crawford, H L; Clark, R M; Fallon, P; Macchiavelli, A O; Baugher, T; Bazin, D; Beausang, C W; Berryman, J S; Bleuel, D L; Campbell, C M; Cromaz, M; de Angelis, G; Gade, A; Hughes, R O; Lee, I Y; Lenzi, S M; Nowacki, F; Paschalis, S; Petri, M; Poves, A; Ratkiewicz, A; Ross, T J; Sahin, E; Weisshaar, D; Wimmer, K; Winkler, R

    2013-06-14

    Intermediate-energy Coulomb excitation measurements are performed on the N ≥ 40 neutron-rich nuclei (66,68)Fe and (64)Cr. The reduced transition matrix elements providing a direct measure of the quadrupole collectivity B(E2;2(1)(+) → 0(1)(+)) are determined for the first time in (68)Fe(42) and (64)Cr(40) and confirm a previous recoil distance method lifetime measurement in (66)Fe(40). The results are compared to state-of-the-art large-scale shell-model calculations within the full fpgd neutron orbital model space using the Lenzi-Nowacki-Poves-Sieja effective interaction and confirm the results of the calculations that show these nuclei are well deformed.

  18. Quadrupole Collectivity in Neutron-Rich Fe and Cr Isotopes

    NASA Astrophysics Data System (ADS)

    Crawford, H. L.; Clark, R. M.; Fallon, P.; Macchiavelli, A. O.; Baugher, T.; Bazin, D.; Beausang, C. W.; Berryman, J. S.; Bleuel, D. L.; Campbell, C. M.; Cromaz, M.; de Angelis, G.; Gade, A.; Hughes, R. O.; Lee, I. Y.; Lenzi, S. M.; Nowacki, F.; Paschalis, S.; Petri, M.; Poves, A.; Ratkiewicz, A.; Ross, T. J.; Sahin, E.; Weisshaar, D.; Wimmer, K.; Winkler, R.

    2013-06-01

    Intermediate-energy Coulomb excitation measurements are performed on the N≥40 neutron-rich nuclei Fe66,68 and Cr64. The reduced transition matrix elements providing a direct measure of the quadrupole collectivity B(E2;21+→01+) are determined for the first time in Fe4268 and Cr4064 and confirm a previous recoil distance method lifetime measurement in Fe4066. The results are compared to state-of-the-art large-scale shell-model calculations within the full fpgd neutron orbital model space using the Lenzi-Nowacki-Poves-Sieja effective interaction and confirm the results of the calculations that show these nuclei are well deformed.

  19. Pharmacokinetic study of amoxicillin in human plasma by solid-phase microextraction followed by high-performance liquid chromatography-triple quadrupole mass spectrometry.

    PubMed

    Szultka, Malgorzata; Krzeminski, Rafal; Walczak, Justyna; Jackowski, Marek; Buszewski, Boguslaw

    2014-02-01

    Sensitive and selective analytical procedures based on high-performance liquid chromatography with mass spectrometric detection were developed for the determination of amoxicillin in human plasma samples. Samples were prepared by applying in-house manufactured molecularly imprinted solid-phase microextraction probes. The detection of target compounds was performed in multiple reaction monitoring mode. The multiple reaction monitoring detection was operated in the positive electrospray ionization mode using the transitions of m/z 366 ([M + H](+) ) → 349 for amoxicillin and m/z 390 ([M + H](+) ) → 372 for gemifloxacin. The method was validated with precision within 15% relative standard deviation and accuracy within 15% relative error. The method was successfully applied to study of the pharmacokinetics of amoxicillin in human plasma after oral administration of amoxicillin.

  20. Distal and proximal ligand interactions in heme proteins: Correlations between C-O and Fe-C vibrational frequencies, oxygen-17 and carbon-13 nuclear magnetic resonance chemical shifts, and oxygen-17 nuclear quadrupole coupling constants in C sup 17 O- and sup 13 CO-labeled species

    SciTech Connect

    Ki Deok Park; Guo, K.; Adebodun, F.; Chiu, M.L.; Sligar, S.G.; Oldfield, E. )

    1991-03-05

    The authors have obtained the oxygen-17 nuclear magnetic resonance (NMR) spectra of a variety of C{sup 17}O-labeled heme proteins, including sperm whale (Physeter catodon) myoglobin, two synthetic sperm whale myoglobin mutants (His E7 {yields} Val E7; His E7 {yields} Phe E7), adult human hemoglobin, rabbit (Oryctolagus cuniculus) hemoglobin, horseradish (Cochlearia armoracia) peroxidase isoenzymes A and C, and Caldariomyces fumago chloroperoxidase, in some cases as a function of pH, and have determined their isotropic {sup 17}O NMR chemical shifts, {delta}{sub i}, and spin-lattice relaxation times, T{sub 1}. They have also obtained similar results on a picket fence prophyrin. The results show an excellent correlation between the infrared C-O vibrational frequencies, {nu}(C-O), and {delta}{sub i}, between {nu}(C-O) and the {sup 17}O nuclear quadrupole coupling constant, and as expected between e{sup 2}qQ/h and {delta}{sub i}. The results suggest the IR and NMR measurements reflect the same interaction, which is thought to be primarily the degree of {pi}-back-bonding from Fe d to CO {pi}* orbitals, as outlined previously.

  1. Determination of liquiritigenin by ultra high performance liquid chromatography coupled with triple quadrupole mass spectrometry: Application to a linear pharmacokinetic study of liquiritigenin in rat plasma.

    PubMed

    Gu, Jie; Li, Huan; Pei, Ke; Cai, Hui; Qin, Kunming; Zhang, Xinghai; Zheng, Lijuan; Liu, Xiao; Cai, Yunqing; Cai, Baochang

    2014-09-17

    A simple, sensitive and rapid ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method has been developed and validated for the quantification of liquiritigenin, a promising anti-tumor agent. Liquiritigenin and the internal standard were separated on an Agilent Extend C18 column and eluted with a gradient mobile phase system of acetonitrile and water. The analysis was performed on a negative ionization electrospray mass spectrometer via multiple reaction monitoring (MRM). Transitions of m/z 255.0→119.0 for liquiritigenin and m/z 269.0→117.0 for the IS were monitored. One-step protein precipitation with acetonitrile was used to remove impurities and extract the analytes from plasma. The method had a chromatographic run time of 4.5min and a good linearity in the range of 1-1000ng/mL. The precision (R.S.D.) of intra-day and inter-day ranged from 4.54 to 10.65% and 5.94 to 13.81%, respectively; while the accuracy of intra-day and inter-day ranged from 104.06 to 109.28% and 94.98 to 112.05%. The recovery and stability were also within the acceptable limits. The validated method was applied to a linear pharmacokinetic study of liquiritigenin in rat plasma for the first time.

  2. DNA Interaction Studies of Selected Polyamine Conjugates

    PubMed Central

    Szumilak, Marta; Merecz, Anna; Strek, Malgorzata; Stanczak, Andrzej; Inglot, Tadeusz W.; Karwowski, Boleslaw T.

    2016-01-01

    The interaction of polyamine conjugates with DNA double helix has been studied. Binding properties were examined by ethidium bromide (EtBr) displacement and DNA unwinding/topoisomerase I/II (Topo I/II) activity assays, as well as dsDNA thermal stability studies and circular dichroism spectroscopy. Genotoxicity of the compounds was estimated by a comet assay. It has been shown that only compound 2a can interact with dsDNA via an intercalative binding mode as it displaced EtBr from the dsDNA-dye complex, with Kapp = 4.26 × 106 M−1; caused an increase in melting temperature; changed the circular dichroism spectrum of dsDNA; converted relaxed plasmid DNA into a supercoiled molecule in the presence of Topo I and reduced the amount of short oligonucleotide fragments in the comet tail. Furthermore, preliminary theoretical study has shown that interaction of the discussed compounds with dsDNA depends on molecule linker length and charge distribution over terminal aromatic chromophores. PMID:27657041

  3. Test results of the LARP Nb$$_3$$Sn quadrupole HQ03a

    DOE PAGES

    DiMarco, J.; G. Ambrosio; Chlachidze, G.; ...

    2016-03-09

    The US LHC Accelerator Research Program (LARP) has been developingmore » $$Nb_3Sn$$ quadrupoles of progressively increasing performance for the high luminosity upgrade of the Large Hadron Collider. The 120 mm aperture High-field Quadrupole (HQ) models are the last step in the R&D phase supporting the development of the new IR Quadrupoles (MQXF). Three series of HQ coils were fabricated and assembled in a shell-based support structure, progressively optimizing the design and fabrication process. The final set of coils consistently applied the optimized design solutions, and was assembled in the HQ03a model. Furthermore, this paper reports a summary of the HQ03a test results, including training, mechanical performance, field quality and quench studies.« less

  4. Test results of the LARP Nb$_3$Sn quadrupole HQ03a

    SciTech Connect

    DiMarco, J.; G. Ambrosio; Chlachidze, G.; Bossert, R.; Holik, T.; Orris, D.; Stoynev, S.; Strauss, T.; Sylvester, C.; Tartaglia, M.; Yu, M.; Anerella, M.; Ghosh, A.; Schmalzle, J.; Wanderer, P.; Borgnolutti, F.; Cheng, D. W.; Dietderich, D.; Felice, H.; Pan, H.; Godeke, A.; Hafalia, A. R.; Marchevsky, M.; Sabbi, G.; Salmi, T.; Wang, X. R.; Ferracin, P.; Bajas, H.; Ravaioli, E.; Todesco, E.

    2016-03-09

    The US LHC Accelerator Research Program (LARP) has been developing $Nb_3Sn$ quadrupoles of progressively increasing performance for the high luminosity upgrade of the Large Hadron Collider. The 120 mm aperture High-field Quadrupole (HQ) models are the last step in the R&D phase supporting the development of the new IR Quadrupoles (MQXF). Three series of HQ coils were fabricated and assembled in a shell-based support structure, progressively optimizing the design and fabrication process. The final set of coils consistently applied the optimized design solutions, and was assembled in the HQ03a model. Furthermore, this paper reports a summary of the HQ03a test results, including training, mechanical performance, field quality and quench studies.

  5. A new high-gradient correction quadrupole for the Fermilab luminosity upgrade

    SciTech Connect

    Mantsch, P.; Carson, J.; Riddiford, A.; Lamm, M.J.

    1989-03-01

    Special superconducting correction quadrupoles are needed for the luminosity upgrade of the Fermilab Tevatron Collider. These correctors are part of the low-beta system for the interaction regions at B/phi/ and D/phi/. The requirements are high gradient and low current. A quadrupole has been designed that meets the operating gradient of 0.63 T/cm at 1086 A. The one-layer quadrupole is wound with a cable consisting of five individually insulated rectangular strands. The five strands are overwrapped with Kapton and epoxy impregnated glass tape. The winding, curing and collaring of the magnet is accomplished in the same manner as Tevatron-like magnets using Rutherford style cable. Once the magnet is complete the five strands are connected in series. A prototype quadrupole has been assembled and tested. The magnet reached a plateau current of 1560 A corresponding to a gradient of 0.91 T/cm without training. The measured field harmonics are substantially better than required. 8 refs., 6 figs., 4 tabs.

  6. LARP Long Quadrupole: A "Long" Step Toward an LHC Luminosity Upgrade with Nb3Sn Magnets

    SciTech Connect

    Ambrosio, Giorgio

    2008-02-13

    The beginning of the development of Nb3Sn magnets for particle accelerators goes back to the 1960's. But only very recently has this development begun to face the challenges of fabricating Nb3Sn magnets which can meet the requirements of modern particle accelerators. LARP (the LHC Accelerator Research Program) is leading this effort focusing on long models of the Interaction Region quadrupoles for a possible luminosity upgrade of the Large Hadron Collider. A major milestone in this development is to test, by the end of 2009, 4m-long quadrupole models, which will be the first Nb3Sn accelerator-type magnets approaching the length of real accelerator magnets. The Long Quadrupoles (LQ) are 'Proof-of-Principle' magnets which are to demonstrate that Nb3Sn technology is sufficiently mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, under development at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. Several challenges must be addressed for the successful fabrication of long Nb3Sn coils and magnets. These challenges and the solutions adopted will be presented together with the main features of the LQ magnets. Several R&D lines are participating to this effort and their contributions will be also presented.

  7. Noise reduction in negative-ion quadrupole mass spectrometry

    DOEpatents

    Chastagner, Philippe

    1993-01-01

    A quadrupole mass spectrometer (QMS) system having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

  8. Noise reduction in negative-ion quadrupole mass spectrometry

    DOEpatents

    Chastagner, P.

    1993-04-20

    A quadrupole mass spectrometer (QMS) system is described having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

  9. Francium Spectroscopy for Weak Interaction Studies

    NASA Astrophysics Data System (ADS)

    Orozco, Luis

    2014-05-01

    Francium, a radioactive element, is the heaviest alkali. Its atomic and nuclear structure makes it an ideal laboratory to study the weak interaction. Laser trapping and cooling in-line with the superconducting LINAC accelerator at Stony Brook opened the precision study of its atomic structure. I will present our proposal and progress towards weak interaction measurements at TRIUMF, the National Canadian Accelerator in Vancouver. These include the commissioning run of the Francium Trapping Facility, hyperfine anomaly measurements on a chain of Fr isotopes, the nuclear anapole moment through parity non-conserving transitions in the ground state hyperfine manifold. These measurements should shed light on the nucleon-nucleon weak interaction. This work is done by the FrPNC collaboration: S. Aubin College of William and Mary, J. A. Behr TRIUMF, R. Collister U. Manitoba, E. Gomez UASLP, G. Gwinner U. Manitoba, M. R. Pearson TRIUMF, L. A. Orozco UMD, M. Tandecki TRIUMF, J. Zhang UMD Supported by NSF and DOE from the USA; TRIUMF, NRC and NSERC from Canada; and CONACYT from Mexico

  10. The Computational Studies of Plasmon Interaction

    NASA Astrophysics Data System (ADS)

    Demchuk, Antonina; Bolesta, Ivan; Kushnir, Oleksii; Kolych, Ihor

    2017-04-01

    In this paper, an interaction of metal nanoparticles that appears in the extinction spectra was investigated. The mutual coupling between the nanoparticles, the effect of size difference, and the interparticle separation in silver nanoparticle dimers are studied by computer discrete dipole approximation methods. The obtained results show that nanoparticle interaction results in the distinct collective modes, known as the low-energy bonding modes and the higher-energy antibounding modes. The spectral position of the modes is analyzed as a function of the ratio of interparticle distance to particle size that reduces the dependency on the particle size itself. The optical spectra of nanoparticles that form the fractal cluster were investigated. It was found that the number of spectral bands increase with the growth of the number of nanoparticles in the fractal cluster, which are described within the plasmon hybridization model.

  11. Molecular interaction studies using microscale thermophoresis.

    PubMed

    Jerabek-Willemsen, Moran; Wienken, Chistoph J; Braun, Dieter; Baaske, Philipp; Duhr, Stefan

    2011-08-01

    Abstract The use of infrared laser sources for creation of localized temperature fields has opened new possibilities for basic research and drug discovery. A recently developed technology, Microscale Thermophoresis (MST), uses this temperature field to perform biomolecular interaction studies. Thermophoresis, the motion of molecules in temperature fields, is very sensitive to changes in size, charge, and solvation shell of a molecule and thus suited for bioanalytics. This review focuses on the theoretical background of MST and gives a detailed overview on various applications to demonstrate the broad applicability. Experiments range from the quantification of the affinity of low-molecular-weight binders using fluorescently labeled proteins, to interactions between macromolecules and multi-component complexes like receptor containing liposomes. Information regarding experiment and experimental setup is based on the Monolith NT.115 instrument (NanoTemper Technologies GmbH).

  12. The Computational Studies of Plasmon Interaction.

    PubMed

    Demchuk, Antonina; Bolesta, Ivan; Kushnir, Oleksii; Kolych, Ihor

    2017-12-01

    In this paper, an interaction of metal nanoparticles that appears in the extinction spectra was investigated. The mutual coupling between the nanoparticles, the effect of size difference, and the interparticle separation in silver nanoparticle dimers are studied by computer discrete dipole approximation methods. The obtained results show that nanoparticle interaction results in the distinct collective modes, known as the low-energy bonding modes and the higher-energy antibounding modes. The spectral position of the modes is analyzed as a function of the ratio of interparticle distance to particle size that reduces the dependency on the particle size itself. The optical spectra of nanoparticles that form the fractal cluster were investigated. It was found that the number of spectral bands increase with the growth of the number of nanoparticles in the fractal cluster, which are described within the plasmon hybridization model.

  13. Molecular Interaction Studies Using Microscale Thermophoresis

    PubMed Central

    Jerabek-Willemsen, Moran; Wienken, Chistoph J.; Braun, Dieter; Baaske, Philipp

    2011-01-01

    Abstract The use of infrared laser sources for creation of localized temperature fields has opened new possibilities for basic research and drug discovery. A recently developed technology, Microscale Thermophoresis (MST), uses this temperature field to perform biomolecular interaction studies. Thermophoresis, the motion of molecules in temperature fields, is very sensitive to changes in size, charge, and solvation shell of a molecule and thus suited for bioanalytics. This review focuses on the theoretical background of MST and gives a detailed overview on various applications to demonstrate the broad applicability. Experiments range from the quantification of the affinity of low-molecular-weight binders using fluorescently labeled proteins, to interactions between macromolecules and multi-component complexes like receptor containing liposomes. Information regarding experiment and experimental setup is based on the Monolith NT.115 instrument (NanoTemper Technologies GmbH). PMID:21812660

  14. Interaction study between remoxipride and biperiden.

    PubMed

    Yisak, W; Farde, L; von Bahr, C; Nilsson, L B; Fredriksson, G; Ogenstad, S

    1993-01-01

    Twelve healthy male volunteers took part in a double-blind randomised cross-over study composed of three treatment sessions: remoxipride 100 mg; remoxipride 100 mg plus biperiden 4 mg; and biperiden 4 mg. Plasma and urine concentrations of remoxipride and biperiden, plasma prolactin levels, salivary flow and adverse events were recorded to assess pharmacodynamic interactions. Remoxipride and biperiden had no effect on each other's plasma concentrations. Biperiden did not affect the urinary recovery or renal clearance of remoxipride. Prolactin levels were unaffected by biperiden but increased following remoxipride administration. Differences in prolactin Cmax and tmax following remoxipride versus concomitant (remoxipride + biperiden) treatment were not statistically significant. However, a slight but statistically significant (P = 0.04) increase in prolactin AUC was observed after concomitant treatment. No significant differences could be observed between the recorded salivary flow in all the treatment sessions. Single doses of remoxipride and biperiden showed no pharmacokinetic or pharmacodynamic interaction.

  15. Multi-Pass Quadrupole Mass Analyzer

    NASA Technical Reports Server (NTRS)

    Prestage, John D.

    2013-01-01

    Analysis of the composition of planetary atmospheres is one of the most important and fundamental measurements in planetary robotic exploration. Quadrupole mass analyzers (QMAs) are the primary tool used to execute these investigations, but reductions in size of these instruments has sacrificed mass resolving power so that the best present-day QMA devices are still large, expensive, and do not deliver performance of laboratory instruments. An ultra-high-resolution QMA was developed to resolve N2 +/CO+ by trapping ions in a linear trap quadrupole filter. Because N2 and CO are resolved, gas chromatography columns used to separate species before analysis are eliminated, greatly simplifying gas analysis instrumentation. For highest performance, the ion trap mode is used. High-resolution (or narrow-band) mass selection is carried out in the central region, but near the DC electrodes at each end, RF/DC field settings are adjusted to allow broadband ion passage. This is to prevent ion loss during ion reflection at each end. Ions are created inside the trap so that low-energy particles are selected by low-voltage settings on the end electrodes. This is beneficial to good mass resolution since low-energy particles traverse many cycles of the RF filtering fields. Through Monte Carlo simulations, it is shown that ions are reflected at each end many tens of times, each time being sent back through the central section of the quadrupole where ultrahigh mass filtering is carried out. An analyzer was produced with electrical length orders of magnitude longer than its physical length. Since the selector fields are sized as in conventional devices, the loss of sensitivity inherent in miniaturizing quadrupole instruments is avoided. The no-loss, multi-pass QMA architecture will improve mass resolution of planetary QMA instruments while reducing demands on the RF electronics for high-voltage/high-frequency production since ion transit time is no longer limited to a single pass. The

  16. Nuclear quadrupole resonance echoes from hexamethylenetetramine.

    PubMed

    Ota, Go; Itozaki, Hideo

    2006-10-01

    We investigated the echo phenomenon of nuclear quadrupole resonance (NQR) from hexamethylenetetramine (HMT). We detected the pure NQR echo signal of HMT with a short pulse interval. The intensity of the echo signal increased as the pulse interval time was decreased. We observed that a clean echo signal was generated even when the pulse interval was shorter than the decay time constant T(2)(*). Since the short interval time gives a strong echo, our result insists that shorter interval time is preferred for the NQR detection.

  17. Dynamical map for combined function magnets with solenoid, dipole, and quadrupole fields

    SciTech Connect

    Venturini, Marco; Wolski, Andy

    2004-06-30

    The interaction regions of colliders invariably include strong solenoid fields. Where quadrupoles and dipoles are embedded in the solenoid, the beam dynamics in the combined fields can be complicated to model using the traditional approach of interleaving slices of the different fields. The complexity increases if the design trajectory is offset from the magnetic axis; this is the case, for example, in PEP-II. In this paper, we present maps for combined solenoid, dipole and quadrupole fields that provide a much simpler alternative to the traditional approach, and show that the deviation of the design trajectory from the magnetic axis can be handle in a straightforward manner. We illustrate the techniques presented by reference to the PEP-II interaction region.

  18. Nuclear quadrupole resonance lineshape analysis for different motional models: stochastic Liouville approach.

    PubMed

    Kruk, D; Earle, K A; Mielczarek, A; Kubica, A; Milewska, A; Moscicki, J

    2011-12-14

    A general theory of lineshapes in nuclear quadrupole resonance (NQR), based on the stochastic Liouville equation, is presented. The description is valid for arbitrary motional conditions (particularly beyond the valid range of perturbation approaches) and interaction strengths. It can be applied to the computation of NQR spectra for any spin quantum number and for any applied magnetic field. The treatment presented here is an adaptation of the "Swedish slow motion theory," [T. Nilsson and J. Kowalewski, J. Magn. Reson. 146, 345 (2000)] originally formulated for paramagnetic systems, to NQR spectral analysis. The description is formulated for simple (Brownian) diffusion, free diffusion, and jump diffusion models. The two latter models account for molecular cooperativity effects in dense systems (such as liquids of high viscosity or molecular glasses). The sensitivity of NQR slow motion spectra to the mechanism of the motional processes modulating the nuclear quadrupole interaction is discussed. © 2011 American Institute of Physics

  19. Spacelab data analysis and interactive control study

    NASA Technical Reports Server (NTRS)

    Tarbell, T. D.; Drake, J. F.

    1980-01-01

    The study consisted of two main tasks, a series of interviews of Spacelab users and a survey of data processing and display equipment. Findings from the user interviews on questions of interactive control, downlink data formats, and Spacelab computer software development are presented. Equipment for quick look processing and display of scientific data in the Spacelab Payload Operations Control Center (POCC) was surveyed. Results of this survey effort are discussed in detail, along with recommendations for NASA development of several specific display systems which meet common requirements of many Spacelab experiments.

  20. Study of Laser Interaction with Thin Targets

    SciTech Connect

    Boley, C D; Cutter, K P; Fochs, S N; Pax, P H; Rotter, M D; Rubenchik, A M; Yamamoto, R M

    2009-03-06

    For many targets of interest, the thickness is small compared to the conduction length during the engagement. In addition, the laser-material interaction region can be treated as flat. We have studied this regime with our 25 kW solid-state laser. We have demonstrated that airflow can reduce by approximately 40% the energy required to break through a thin target. This reduction is caused by the bulging of the softened material and the tearing and removal of the material by aerodynamic forces. We present elastic modeling which explains these results.

  1. Ultra-high-performance liquid chromatography-quadrupole/time of flight mass spectrometry based chemical profiling approach to rapidly reveal chemical transformation of sulfur-fumigated medicinal herbs, a case study on white ginseng.

    PubMed

    Li, Song-Lin; Shen, Hong; Zhu, Ling-Ying; Xu, Jun; Jia, Xiao-Bin; Zhang, Hong-Mei; Lin, Ge; Cai, Hao; Cai, Bao-Chang; Chen, Shi-Lin; Xu, Hong-Xi

    2012-03-30

    Sulfur-fumigation may induce chemical transformation of medicinal herbs. Development of rapid method to reveal potential sulfur-fumigation induced chemical transformation of herbs is a very important issue for efficacy and safety of herb application. In present study, a new strategy was proposed to rapidly reveal chemical transformation of sulfur-fumigated herbs by ultra-high-performance liquid chromatography-quadrupole/time of flight mass spectrometry (UHPLC-QTOF-MS/MS) based chemical profiling approach. The non-fumigated herb was water-wetted and further treated with burning sulfur to get sulfur-fumigated herb. Then the chemical fingerprints of both non-fumigated and sulfur-fumigated samples were compared by UHPLC-QTOF-MS/MS analysis. The identities of all detected peaks, in particular those newly generated in sulfur-fumigated samples were confirmed by comparing the mass spectra and retention times of peaks with that of reference compounds, and/or tentatively assigned by matching empirical molecular formula with that of published compounds, and/or elucidating quasi-molecular ions and fragment ions referring to available literature information. The identification could be rationalized through deducing possible reactions involved in the generation of these newly detected compounds. The proposed strategy was extensively investigated in the case of white ginseng. Total 82 components were detected in non-fumigated and sulfur-fumigated white ginseng samples, among them 35 sulfur-containing compounds detected only in sulfur-fumigated white ginseng and its decoction were assigned to be sulfate or sulfite derivatives of original ginsenosides, and were deduced to be generated via reactions of esterification, addition, hydrolysis and dehydration during sulfur-fumigation and decocting of white ginseng. The established approach was applied to discriminate sulfur-fumigated white ginseng among commercial samples from America, Canada, and Hong Kong SAR, Macau SAR and Mainland of

  2. Consistent quadrupole-octupole collective model

    NASA Astrophysics Data System (ADS)

    Dobrowolski, A.; Mazurek, K.; Góźdź, A.

    2016-11-01

    Within this work we present a consistent approach to quadrupole-octupole collective vibrations coupled with the rotational motion. A realistic collective Hamiltonian with variable mass-parameter tensor and potential obtained through the macroscopic-microscopic Strutinsky-like method with particle-number-projected BCS (Bardeen-Cooper-Schrieffer) approach in full vibrational and rotational, nine-dimensional collective space is diagonalized in the basis of projected harmonic oscillator eigensolutions. This orthogonal basis of zero-, one-, two-, and three-phonon oscillator-like functions in vibrational part, coupled with the corresponding Wigner function is, in addition, symmetrized with respect to the so-called symmetrization group, appropriate to the collective space of the model. In the present model it is D4 group acting in the body-fixed frame. This symmetrization procedure is applied in order to provide the uniqueness of the Hamiltonian eigensolutions with respect to the laboratory coordinate system. The symmetrization is obtained using the projection onto the irreducible representation technique. The model generates the quadrupole ground-state spectrum as well as the lowest negative-parity spectrum in 156Gd nucleus. The interband and intraband B (E 1 ) and B (E 2 ) reduced transition probabilities are also calculated within those bands and compared with the recent experimental results for this nucleus. Such a collective approach is helpful in searching for the fingerprints of the possible high-rank symmetries (e.g., octahedral and tetrahedral) in nuclear collective bands.

  3. SSC Quadrupole Magnet Performance at LBL

    SciTech Connect

    Lietzke, A.F.; Barale, P.; Benjegerdes, r.; Caspi, S.; Cortella, J.; Dell'Orco, D.; Gilbert, W.; Green, M.I.; Mirk, K.; Peters, C.; Scalan, R.; Taylor, C.E.; Wandesforde, A.

    1992-10-01

    Lawrence Berkeley Laboratory (LBL) contracted to design, construct, and test four short (1m) models and six full-size (5m) models of the Superconducting Super Collider (SSC) main-ring 5 meter focusing quadrupole magnet (211 Tesla/meter). The training performance of these magnets is summarized. Magnets were tested in a horizontal boiling helium (1 Atm) cryostat. The magnetic, strain-gage and training responses to two thermal cycles were measured. The quadrupole gradient, and relative multipole purity were determined from Fourier analysis of the rotating coil signals. Magnetic and strain-gage measurements were taken on-the-fly. The voltage-tap data was analyzed to determine quench-origin and propagation characteristics. Quench-training proceeded at 4.3K until a plateau was achieved or sub-cooling (2.5K) was used to accelerate the training process. The early short (1m) magnets were also trained at 1.8K (10kA) to help identify potential weak areas. The MIITs were calculated to compare various magnet protection methods. Except for modest training above the anticipated SSC operating point, the magnets performed very well and proved to be self-protecting. Some design flaws were identified and corrected. The last two 1 m models and all the 5m models have been reinstalled in cryostats at the SSC Laboratory, retested and used to achieve various milestones in their program.

  4. Explosives detection with quadrupole resonance analysis

    NASA Astrophysics Data System (ADS)

    Rayner, Timothy J.; Thorson, Benjamin D.; Beevor, Simon; West, Rebecca; Krauss, Ronald A.

    1997-02-01

    The increase in international terrorist activity over the past decade has necessitated the exploration of new technologies for the detection of plastic explosives. Quadrupole resonance analysis (QRA) has proven effective as a technique for detecting the presence of plastic, sheet, and military explosive compounds in small quantities, and can also be used to identify narcotics such as heroin and cocaine base. QRA is similar to the widely used magnetic resonance (MR) and magnetic resonance imaging (MRI) techniques, but has the considerable advantage that the item being inspected does not need to be immersed in a steady, homogeneous magnetic field. The target compounds are conclusively identified by their unique quadrupole resonance frequencies. Quantum magnetics has develop and introduced a product line of explosives and narcotics detection devices based upon QRA technology. The work presented here concerns a multi-compound QRA detection system designed to screen checked baggage, cargo, and sacks of mail at airports and other high-security facilities. The design philosophy and performance are discussed and supported by test results from field trials conducted in the United States and the United Kingdom. This detection system represents the current state of QRA technology for field use in both commercial and government sectors.

  5. Quadrupole Collectivity in Neutron Deficient Sn Isotopes

    NASA Astrophysics Data System (ADS)

    Gade, Alexandra

    2014-03-01

    One of the overarching goals of nuclear physics is the development of a comprehensive model of the atomic nucleus with predictive power across the nuclear chart. Of particular importance for the development of nuclear models is experimental data that consistently track the effect of isospin and changed binding, for example. The chain of Sn isotopes has been a formidable testing ground for nuclear models as some spectroscopic data is available from N = Z = 50 100Sn in the proximity of the proton dripline to 134Sn, beyond the very neutron-rich doubly magic nucleus 132Sn. In even-even nuclei, the electromagnetic quadrupole excitation strength is a measure of quadrupole collectivity, sensitive to the presence of shell gaps, nuclear deformation, and nucleon-nucleon correlations, for example. In the Sn isotopes, this transition strength has been reported from 104Sn to 130Sn, spanning a chain of 14 even-even Sn isotopes. The trend is asymmetric with respect to midshell and not even the largest-scale shell-model calculations have been able to describe the evolution of transition strength across the isotopic chain without varying effective charges. Implications will be discussed. This work was supported by the National Science Foundation under Grant No. PHY-1102511.

  6. Studying Haloanisoles Interaction with Olfactory Receptors.

    PubMed

    Silva Teixeira, Carla S; Silva Ferreira, António C; Cerqueira, Nuno M F S A

    2016-07-20

    the theoretical and experimental results also lead us to study the potential interaction of the haloanisoles, TCA, TBA, and TCP with these ORs. The results have shown that these compounds can compete with other known agonists/antagonists for the access to the binding regions of ORs. These results may partially explain the capability of these compounds to give a musty odor to food and beverages at very low concentrations.

  7. The electric quadrupole moment of molecular hydrogen ions and their potential for a molecular ion clock

    NASA Astrophysics Data System (ADS)

    Bakalov, D.; Schiller, S.

    2014-01-01

    The systematic shifts of the transition frequencies in the molecular hydrogen ions are of relevance to ultra-high-resolution radio-frequency, microwave and optical spectroscopy of these systems, performed in ion traps. We develop the ab initio description of the interaction of the electric quadrupole moment of this class of molecules with the static electric field gradients present in ion traps. In good approximation, it is described in terms of an effective perturbation Hamiltonian. An approximate treatment is then performed in the Born-Oppenheimer approximation. We give an expression of the electric quadrupole coupling parameter valid for all hydrogen molecular ion species and evaluate it for a large number of states of H{2/+}, HD+, and D{2/+}. The systematic shifts can be evaluated as simple expectation values of the perturbation Hamiltonian. Results on radio-frequency, one-photon electric dipole (E1), and two-photon E1 transitions between hyperfine states in HD+ are reported. For two-photon E1 transitions between rotationless states, the shifts vanish. For a large subset of rovibrational one-photon transitions, the absolute values of the quadrupole shifts range from 0.3 to 10 Hz for an electric field gradient of 108 V/m2. We point out an experimental procedure for determining the quadrupole shift which will allow reducing its contribution to the uncertainty of unperturbed rovibrational transition frequencies to the 1 × 10-15 fractional level and, for selected transitions, even below it. The combined contributions of black-body radiation, Zeeman, Stark and quadrupole effects are considered for a large set of transitions, and it is estimated that the total transition frequency uncertainty of selected transitions can be reduced below the 1 × 10-15 level.

  8. Electrostatic quadrupole focused particle accelerating assembly with laminar flow beam

    DOEpatents

    Maschke, A.W.

    1984-04-16

    A charged particle accelerating assembly provided with a predetermined ratio of parametric structural characteristics and with related operating voltages applied to each of its linearly spaced focusing and accelerating quadrupoles, thereby to maintain a particle beam traversing the electrostatic fields of the quadrupoles in the assembly in an essentially laminar flow through the assembly.

  9. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2016-11-15

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  10. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  11. Electrostatic quadrupole focused particle accelerating assembly with laminar flow beam

    DOEpatents

    Maschke, Alfred W.

    1985-01-01

    A charged particle accelerating assembly provided with a predetermined ratio of parametric structural characteristics and with related operating voltages applied to each of its linearly spaced focusing and accelerating quadrupoles, thereby to maintain a particle beam traversing the electrostatic fields of the quadrupoles in the assembly in an essentially laminar flow throughout the assembly.

  12. Joint and angle-covariant spin measurements with a quadrupole magnetic field

    NASA Technical Reports Server (NTRS)

    Martens, Hans; Demuynck, Willem M.

    1994-01-01

    We study a Stern-Gerlach type setup, with a quadrupole magnetic field, for neutral particles of arbitrary spin. The Hamiltonian is of a form proposed for joint measurements of the incompatible observables. The measurement results are discussed, showing the limitation of such Hamiltonians. Some remarks are made on the relevance of covariance as a criterion for measurement schemes.

  13. Support Structure Design of the $\\hbox{Nb}_{3}\\hbox{Sn}$ Quadrupole for the High Luminosity LHC

    SciTech Connect

    Juchno, M.; Ambrosio, G.; Anerella, M.; Cheng, D.; Felice, H.; Ferracin, P.; Perez, J. C.; Prin, H.; Schmalzle, J.

    2014-10-31

    New low-β quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb₃Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of the detailed 3D numerical analysis performed in preparation for the first short model test.

  14. Restoring the skew quadrupole moment in the Tevatron dipoles

    SciTech Connect

    Harding, D.J.; Bauer, P.C.; Blowers, J.N.; DiMarco, J.; Glass, H.D.; Hanft, R.W.; Carson, J.A.; Robotham, W.F.; Tartaglia, M.A.; Tompkins, J.C.; Velev, G.; /Fermilab

    2005-05-01

    In early 2003 it was realized that mechanical changes in the Tevatron dipoles had led to a deterioration of the magnetic field quality that was hindering operation of the accelerator. After extensive study, a remediation program was started in late 2003 that will continue through 2005. The mechanical and magnetic effects are discussed. The readjustment process and experience are reported, along with other observations on aging magnets. In January 2003 two lines of inquiry converged, leading to the recognition that the severe betatron coupling that was hindering operation of the Tevatron could be explained by a systematic shift on the skew quadrupole field in the dipole magnets of the same size expected from observed mechanical movement of the coils inside the magnet yokes [1]. This paper reports on subsequent magnet studies that were conducted in parallel with additional beam studies and accelerator modeling [2] exploring the feasibility of the eventual remediation effort [3].

  15. Interactivity with the Interactive Whiteboard in Traditional and Innovative Primary Schools: An Exploratory Study

    ERIC Educational Resources Information Center

    de Koster, Sandra; Volman, Monique; Kuiper, Els

    2013-01-01

    One of the main affordances of the interactive whiteboard (IWB) is its potential for increasing classroom interactivity, yet little is known about the interactivity it supports in schools with different educational concepts. In this study we analysed what types of whole-class interactivity the IWB supports in schools with either a…

  16. Synchrotron Tune Adjustment by Longitudinal Motion of Quadrupoles

    NASA Astrophysics Data System (ADS)

    Bertsche, K. J.

    1996-05-01

    Adjustment of the tune of a synchrotron is generally accomplished by globally varying the strength of quadrupoles, either in the main quadrupole bus or in a set of dedicated trim quadrupoles distributed around the ring. An alternate scheme for tune control involves varying the strengths of quadrupoles only within a local insert, thereby adjusting the phase advance across this insert to create a "phase trombone." In a synchrotron built of permanent magnets, such as the proposed Fermilab Recycler Ring, tune adjustment may also be accomplished by constructing a phase trombone in which the longitudinal position rather than strength of a number of quadrupoles is adjusted. Design philosophies and performance for such phase trombones will be presented. *Operated by Universities Research Association, Inc., under contract with the US. Department of Energy.

  17. Electric quadrupole moments of 17/2{sup -} and 13/2{sup -} subsequent isomers in {sup 209}Po

    SciTech Connect

    Nicolescu, G.; Ivanov, E. A.; Plostinaru, D.

    2009-04-15

    The electric quadrupole interaction of {sup 209}Po high spin isomers in a Bi single crystal has been investigated by the time-differential perturbed angular distribution (TDPAD) technique. A two-level analysis procedure for the 17/2{sup -}and 13/2{sup -} subsequent isomers was employed. The spectroscopic electric quadrupole moments were measured as |Q(17/2{sup -})|=65.9(7)e fm{sup 2} and |Q(13/2{sup -})|=12.6(5)e fm{sup 2}. The experimental values of equilibrium deformations were extracted.

  18. Supersonic Quadrupole Noise Theory for High-Speed Helicopter Rotors

    NASA Technical Reports Server (NTRS)

    Farassat, F.; Brentner, Kenneth S.

    1997-01-01

    High-speed helicopter rotor impulsive noise prediction is an important problem of aeroacoustics. The deterministic quadrupoles have been shown to contribute significantly to high-speed impulsive (HSI) noise of rotors, particularly when the phenomenon of delocalization occurs. At high rotor-tip speeds, some of the quadrupole sources lie outside the sonic circle and move at supersonic speed. Brentner has given a formulation suitable for efficient prediction of quadrupole noise inside the sonic circle. In this paper, we give a simple formulation based on the acoustic analogy that is valid for both subsonic and supersonic quadrupole noise prediction. Like the formulation of Brentner, the model is exact for an observer in the far field and in the rotor plane and is approximate elsewhere. We give the full analytic derivation of this formulation in the paper. We present the method of implementation on a computer for supersonic quadrupoles using marching cubes for constructing the influence surface (Sigma surface) of an observer space- time variable (x; t). We then present several examples of noise prediction for both subsonic and supersonic quadrupoles. It is shown that in the case of transonic flow over rotor blades, the inclusion of the supersonic quadrupoles improves the prediction of the acoustic pressure signature. We show the equivalence of the new formulation to that of Brentner for subsonic quadrupoles. It is shown that the regions of high quadrupole source strength are primarily produced by the shock surface and the flow over the leading edge of the rotor. The primary role of the supersonic quadrupoles is to increase the width of a strong acoustic signal.

  19. Interaction Between Flames and Electric Fields Studied

    NASA Technical Reports Server (NTRS)

    Yuan, Zeng-Guang; Hegde, Uday

    2003-01-01

    The interaction between flames and electric fields has long been an interesting research subject that has theoretical importance as well as practical significance. Many of the reactions in a flame follow an ionic pathway: that is, positive and negative ions are formed during the intermediate steps of the reaction. When an external electric field is applied, the ions move according to the electric force (the Coulomb force) exerted on them. The motion of the ions modifies the chemistry because the reacting species are altered, it changes the velocity field of the flame, and it alters the electric field distribution. As a result, the flame will change its shape and location to meet all thermal, chemical, and electrical constraints. In normal gravity, the strong buoyant effect often makes the flame multidimensional and, thus, hinders the detailed study of the problem.

  20. Electron Cloud Generation and Trapping in a Quadrupole Magnet at the Los Alamos Proton Storage Ring

    SciTech Connect

    Macek, Robert J.; Browman, Andrew A.; Ledford, John E.; Borden, Michael J.; O'Hara, James F.; McCrady, Rodney C.; Rybarcyk, Lawrence J.; Spickermann, Thomas; Zaugg, Thomas J.; Pivi, Mauro T.F.; /SLAC

    2008-03-17

    Recent beam physics studies on the two-stream e-p instability at the LANL proton storage ring (PSR) have focused on the role of the electron cloud generated in quadrupole magnets where primary electrons, which seed beam-induced multipacting, are expected to be largest due to grazing angle losses from the beam halo. A new diagnostic to measure electron cloud formation and trapping in a quadrupole magnet has been developed, installed, and successfully tested at PSR. Beam studies using this diagnostic show that the 'prompt' electron flux striking the wall in a quadrupole is comparable to the prompt signal in the adjacent drift space. In addition, the 'swept' electron signal, obtained using the sweeping feature of the diagnostic after the beam was extracted from the ring, was larger than expected and decayed slowly with an exponential time constant of 50 to 100 {micro}s. Other measurements include the cumulative energy spectra of prompt electrons and the variation of both prompt and swept electron signals with beam intensity. Experimental results were also obtained which suggest that a good fraction of the electrons observed in the adjacent drift space for the typical beam conditions in the 2006 run cycle were seeded by electrons ejected from the quadrupole.

  1. Study of electron-positron interactions

    SciTech Connect

    Abashian, A.; Gotow, K.; Philonen, L.

    1990-09-15

    For the past seven years, this group has been interested in the study of tests of the Standard Model of Electroweak interactions. The program has centered about the AMY experiment which examines the nature of the final state products in electron-positron collisions in the center of mass energy range near 60 GeV. Results of these measurements have shown a remarkable consistency with the predictions of the minimal model of 3 quark and lepton generations and single charged and neutral intermediate bosons. No new particles or excited states have been observed nor has any evidence for departures in cross sections or angular asymmetries from expectations been observed. These conclusions have been even more firmly established by the higher energy results from the LEP and SLC colliders at center of mass energies of about 90 GeV. Our focus is shifting to the neutrino as a probe to electroweak interactions. The relative merit of attempting to observe neutrinos from point sources versus observing neutrinos generally is not easy to predict. The improved ability to interpret is offset by the probably episodic nature of the emission and irreproducibility of the results. In this phase of development, it is best to be sensitive to both sources of neutrinos. As a second phase of our program at Virginia Tech, we are studying the feasibility of detecting cosmic ray neutrinos in a proposed experiment which we have called NOVA. the results of the test setup will be instrumental in developing an optimum design. A third program we are involved in is the MEGA experiment at Los Alamos, an experiment to place a limit on the rate of muon decay to electron plus photon which is forbidden by the Standard Model.

  2. Multipole contribution from an off-axis orbit in an IR quadrupole and the consequences on the dynamic aperture

    NASA Astrophysics Data System (ADS)

    Sullivan, M.; Caspi, S.; Forest, E.; Robin, D.; Zholents, A.; Cai, Y.; Destaebler, H.; Donald, M.; Helm, R.; Irwin, J.

    1994-06-01

    The low-energy beam of the proposed PEP-II B factory enters the first quadrupole (Q1) after the interaction point off axis in order to separate the low-energy beam from the high-energy beam. The off-axis beam orbit in Q1 gives rise to significant feed-down terms from higher multipoles that originate from systematic effects and random fabrication errors. The authors study superconducting and permanent magnet designs of Q1, and look at the effect these different designs have on the dynamic aperture. Including a dipole field in a superconducting design allows one to offset the magnetic axis from the mechanical axis, thereby maintaining the separation of the beams while greatly reducing the feed-down effect. They illustrate relevant points of the discussion with tracking results for the PEP-II low-energy ring.

  3. RADIATION RESISTANT HTS QUADRUPOLES FOR RIA.

    SciTech Connect

    GUPTA,R.; ANERELLA,M.; HARRISON,M.; ET AL.

    2004-10-03

    Extremely high radiation, levels with accumulated doses comparable to those in nuclear reactors than in accelerators, and very high heat loads ({approx}15 kw) make the quadrupole magnets in the fragment separator one of the most challenging elements of the proposed Rare Isotope Accelerator (RIA). Removing large heat loads, protecting the superconducting coils against quenching, the long term survivability of magnet components, and in particular, insulation that can retain its functionality in such a harsh environment, are the major challenges associated with such magnets. A magnet design based on commercially available high temperature superconductor (HTS) and stainless steel tape insulation has been developed. HTS will efficiently remove these large heat loads and stainless steel can tolerate these large radiation doses. Construction of a model magnet has been started with several coils already built and tested. This paper presents the basic magnet design, results of the coil tests, the status and the future plans. In addition, preliminary results of radiation calculations are also presented.

  4. Quadrupole resonance scanner for narcotics detection

    NASA Astrophysics Data System (ADS)

    Shaw, Julian D.; Moeller, C. R.; Magnuson, Erik E.; Sheldon, Alan G.

    1994-10-01

    Interest in non-invasive, non-hazardous, bulk detection technologies for narcotics interdiction has risen over the last few years. As part of our continuing research and development programs in detection of narcotics and explosives using sensitive magnetic measuring devices, we present the first commercially available prototype Quadrupole Resonance (QR) scanner for narcotics detection. The portable narcotics detection system was designed in modular form such that a single QR base system could be easily used with a variety of custom detection heads. The QR system presented in this paper is suitable for scanning items up to 61 X 35 X 13 cm in size, and was designed to scan mail packages and briefcase-sized items for the presence of narcotics. System tests have shown that detection sensitivity is comparable that obtained in laboratory systems.

  5. Explosives detection by nuclear quadrupole resonance (NQR)

    NASA Astrophysics Data System (ADS)

    Garroway, Allen N.; Buess, Michael L.; Yesinowski, James P.; Miller, Joel B.; Krauss, Ronald A.

    1994-10-01

    Pure nuclear quadrupole resonance (NQR) of 14N nuclei is quite promising as a method for detecting explosives such as RDX and contraband narcotics such as cocaine and heroin in quantities of interest. Pure NQR is conducted without an external applied magnetic field, so potential concerns about damage to magnetically encoded data or exposure of personnel to large magnetic fields are not relevant. Because NQR frequencies of different compounds are quite distinct, we do not encounter false alarms from the NQR signals of other benign materials. We have constructed a laboratory prototype NQR explosives detector which interrogates a volume of 300 liters (10 ft3). This paper presents abbreviated results from a demonstration of the laboratory prototype NQR explosives detector conducted at the Federal Aviation Administration Technical Center in May 1994 on RDX-based explosives.

  6. An improved integrally formed radio frequency quadrupole

    DOEpatents

    Abbott, S.R.

    1987-10-05

    An improved radio frequency quadrupole is provided having an elongate housing with an elongate central axis and top, bottom and two side walls symmetrically disposed about the axis, and vanes formed integrally with the walls, the vanes each having a cross-section at right angles to the central axis which tapers inwardly toward the axis to form electrode tips spaced from each other by predetermined distances. Each of the four walls, and the vanes integral therewith, is a separate structural element having a central lengthwise plane passing through the tip of the vane, the walls having flat mounting surfaces at right angles to and parallel to the control plane, respectively, which are butted together to position the walls and vane tips relative to each other. 4 figs.

  7. Atomic Quadrupole Moment Measurement Using Dynamic Decoupling.

    PubMed

    Shaniv, R; Akerman, N; Ozeri, R

    2016-04-08

    We present a method that uses dynamic decoupling of a multilevel quantum probe to distinguish small frequency shifts that depend on m_{j}^{2}, where m_{j}^{2} is the angular momentum of level |j⟩ along the quantization axis, from large noisy shifts that are linear in m_{j}, such as those due to magnetic field noise. Using this method we measured the electric-quadrupole moment of the 4D_{5/2} level in ^{88}Sr^{+} to be 2.973_{-0.033}^{+0.026}ea_{0}^{2}. Our measurement improves the uncertainty of this value by an order of magnitude and thus helps mitigate an important systematic uncertainty in ^{88}Sr^{+} based optical atomic clocks and verifies complicated many-body quantum calculations.

  8. Hybrid high gradient permanent magnet quadrupole

    NASA Astrophysics Data System (ADS)

    N'gotta, P.; Le Bec, G.; Chavanne, J.

    2016-12-01

    This paper presents an innovative compact permanent magnet quadrupole with a strong gradient for potential use in future light source lattices. Its magnetic structure includes simple mechanical parts, rectangular permanent magnet blocks and soft iron poles. It has a wide aperture in the horizontal plane to accommodate an x-ray beam port, a common constraint in storage ring-based light sources. This specificity introduces field quality deterioration because of the resulting truncation of the poles; a suitable field quality can be restored with an optimized pole shape. A 82 T /m prototype with a bore radius of 12 mm and a 10 mm vertical gap between poles has been constructed and magnetically characterized. Gradient inhomogeneities better than 10-3 in the good field region were obtained after the installation of special shims.

  9. Characterization of the ELIMED prototype permanent magnet quadrupole system

    NASA Astrophysics Data System (ADS)

    Russo, A. D.; Schillaci, F.; Pommarel, L.; Romano, F.; Amato, A.; Amico, A. G.; Calanna, A.; Cirrone, G. A. P.; Costa, M.; Cuttone, G.; Amato, C.; De Luca, G.; Flacco, F. A.; Gallo, G.; Giove, D.; Grmek, A.; La Rosa, G.; Leanza, R.; Maggiore, M.; Malka, V.; Milluzzo, G.; Petringa, G.; Pipek, J.; Scuderi, V.; Vauzour, B.; Zappalà, E.

    2017-01-01

    The system described in this work is meant to be a prototype of a more performing one that will be installed at ELI-Beamlines in Prague for the collection of ions produced after the interaction Laser-target, [1]. It has been realized by the researchers of INFN-LNS (Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare) and SIGMAPHI, a French company, using a system of Permanent Magnet Quadrupoles (PMQs), [2]. The final system that will be installed in Prague is designed for protons and carbons up to 60 MeV/u, around 10 times more than the energies involved in the present work. The prototype, shown in this work, has been tested in collaboration with the SAPHIR experimental facility group at LOA (Laboratoire d'Optique Appliqueé) in Paris using a 200 TW Ti:Sapphire laser system. The purpose of this work is to validate the design and the performances of this large and compact bore system and to characterize the beam produced after the interaction laser-target and its features. Moreover, the optics simulations have been compared with a real beam shape on a GAFChromic film. The procedure used during the experimental campaign and the most relevant results are reported here demonstrating a good agreement with the simulations and a good control on the beam optics.

  10. Linear and nonlinear studies at RHIC interaction regions and optical design of the rapid cycling medical synchrotron

    NASA Astrophysics Data System (ADS)

    Cardona, Javier Fernando

    Development and application of the action and phase technique used to evaluate and correct local errors, linear and non linear (skew quadrupole errors, gradient errors and sextupole errors), at RHIC interaction regions is presented in the first part of this thesis. The skew quadrupole errors have their origin on the roll angles of the quadrupoles. It is then possible to estimate the skew quadrupole error present in a RHIC triplet if all the roll angles of the quadrupoles of a particular triplet are known. These values were estimated with the measured roll angles during the 2002 RHIC shutdown period and compared to the measured skew quadrupole errors obtained with the action and phase technique. The agreement is fairly good validating the action and phase technique for at least skew quadrupole errors. Another way of validating the action and phase technique is by intentionally introducing known values of errors while attempting to measure the values with the technique. This was done for skew quadrupole errors and gradient errors with excellent results. Analysis of some of the experiments shows that the set errors can be reproduced by the technique with accuracies below 5 percent. Same experiments were repeated for sextupole errors an a clear correlation between the measured and the set error was found but the precision in this case is not as good as for the linear errors case. The optical design of the Rapid Cycling Medical Synchrotron and related efforts to optimize the design are presented in the second part of this thesis. An interesting outcome of this work is the development of the so called IBEFUMFO technique which allow a better understanding of the optical parameters involved in a lattice design and hence facilitate the task of the designer. The rapid repetition frequency of the RCMS has raised concerns about the sextupole components induced in the beam due to strong Eddy currents. Tracking simulations with Marylie have been done in order to evaluate the

  11. Optimal filtering in multipulse sequences for nuclear quadrupole resonance detection

    NASA Astrophysics Data System (ADS)

    Osokin, D. Ya.; Khusnutdinov, R. R.; Mozzhukhin, G. V.; Rameev, B. Z.

    2014-05-01

    The application of the multipulse sequences in nuclear quadrupole resonance (NQR) detection of explosive and narcotic substances has been studied. Various approaches to increase the signal to noise ratio (SNR) of signal detection are considered. We discussed two modifications of the phase-alternated multiple-pulse sequence (PAMS): the 180° pulse sequence with a preparatory pulse and the 90° pulse sequence. The advantages of optimal filtering to detect NQR in the case of the coherent steady-state precession have been analyzed. It has been shown that this technique is effective in filtering high-frequency and low-frequency noise and increasing the reliability of NQR detection. Our analysis also shows the PAMS with 180° pulses is more effective than PSL sequence from point of view of the application of optimal filtering procedure to the steady-state NQR signal.

  12. Thermal noise in aqueous quadrupole micro- and nano-traps

    SciTech Connect

    Park, Jae; Krstić, Predrag S.

    2012-01-01

    Recent simulations and experiments with aqueous quadrupole micro-traps have confirmed a possibility for control and localization of motion of a charged particle in a water environment, also predicting a possibility of further reduction of the trap size to tens of nano-meters for trapping charged bio-molecules and DNA segments. We study the random thermal noise due to Brownian motion in water which significantly influences the trapping of particles in an aqueous environment. We derive the exact, closed-form expressions for the thermal fluctuations of position and velocity of a trapped particle and thoroughly examine the properties of the rms for the fluctuations as functions of the system parameters and time. The instantaneous signal transferring mechanism between the velocity and position fluctuations could not be achieved in the previous phase-average approaches.

  13. Thermal noise in aqueous quadrupole micro- and nano-traps

    DOE PAGES

    Park, Jae; Krstić, Predrag S.

    2012-01-01

    Recent simulations and experiments with aqueous quadrupole micro-traps have confirmed a possibility for control and localization of motion of a charged particle in a water environment, also predicting a possibility of further reduction of the trap size to tens of nano-meters for trapping charged bio-molecules and DNA segments. We study the random thermal noise due to Brownian motion in water which significantly influences the trapping of particles in an aqueous environment. We derive the exact, closed-form expressions for the thermal fluctuations of position and velocity of a trapped particle and thoroughly examine the properties of the rms for the fluctuationsmore » as functions of the system parameters and time. The instantaneous signal transferring mechanism between the velocity and position fluctuations could not be achieved in the previous phase-average approaches.« less

  14. Anatoxins and degradation products, determined using hybrid quadrupole time-of-flight and quadrupole ion-trap mass spectrometry: forensic investigations of cyanobacterial neurotoxin poisoning.

    PubMed

    James, Kevin J; Crowley, Janet; Hamilton, Brett; Lehane, Mary; Skulberg, Olav; Furey, Ambrose

    2005-01-01

    The potent neurotoxins from cyanobacteria, anatoxin-a (AN), its methyl analogue, homoanatoxin-a (HMAN), and their degradation products, have been studied using nano-electrospray hybrid quadrupole time-of-flight mass spectrometry (QqTOF-MS). The anatoxin degradation products, which are readily produced in vivo by either reduction or epoxidation, were also examined in this study. The high mass accuracy QqTOF-MS data was used to confirm formula assignments for major product ions and quadrupole ion-trap (QIT)-MS was used to construct fragmentation pathways for anatoxins. Significant differences between these fragmentation pathways were observed. Comparisons between the spectra of compounds that differ in side-chain length (the AN and HMAN series) were used to identify ions that are characteristic of the homologues. The application to forensic samples in which the principal neurotoxin had undergone rapid biodegradation has been demonstrated and used to confirm anatoxin poisoning of dogs. Copyright 2005 John Wiley & Sons, Ltd.

  15. Beam dynamics and stability analysis of an intense beam in a continuously twisted quadrupole focusing channel

    NASA Astrophysics Data System (ADS)

    Goswami, A.; Sing Babu, P.; Pandit, V. S.

    2016-11-01

    This paper describes the dynamics of a space-charge-dominated beam through a continuously twisted quadrupole magnet using ten independent first-order differential equations of the beam matrix elements under the assumption of linear space-charge force. Various beam optical properties of the magnet and the evolution of the emittance that results from the coupling between the two transverse planes are studied. The perturbed equations of motion around the matched beam envelopes have been derived and utilized to analyze the stability properties of the intense beam transport by calculating the eigenvalues of the transfer map over one lattice period. Detailed analysis shows the presence of instability due to parametric resonances in a twisted quadrupole channel which generally does not appear in the FODO quadrupole channel. A 2D particle-in-cell simulation code has been developed and utilized to verify the analytical results and to examine the behavior of the intense beam with Gaussian (GA) distribution in the twisted quadrupole channel.

  16. The use of stability bands to improve the performance of quadrupole mass filters

    NASA Astrophysics Data System (ADS)

    Sudakov, M. Yu.; Mamontov, E. V.

    2017-01-01

    The possibility of increasing the resolving power of quadrupole mass filters has been discussed. It has been shown that the limitations associated with the finite time of flight imposed by Von Zahn's rule are modified while using the islands of stability that appear when quadrupole is excited by the additional signals. By calculation of the exponential increment of growth of the oscillation amplitude the effect of the acceleration of mass separation and improvement of the peak shape, when the islands of stability are used for ion filtering, is explained. The case of the excitation by two signals at different frequencies has been studied theoretically. The conditions under which suppression of the first order resonance for one of the directions of motion is obtained. The direct modeling of the peak shape of the mass filter shows the possibility of obtaining a resolution of 10,000 with a time of flight of ions through the quadrupole of 100 cycles of the main RF supply, and low sensitivity of the new operating mode to the nonlinear field distortions in the quadrupoles with rods of circular cross sections.

  17. Magnetic field measurements of quadrupoles in the High-Current Experiment

    NASA Astrophysics Data System (ADS)

    Seidl, P. A.; Kireeff Covo, M.; Baca, D.; Faltens, A.; Molvik, A. W.; Ritchie, G.; Sabbi, G.; Shuman, D.

    2005-05-01

    The High-Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. Four pulsed magnetic quadrupoles are being used to study gas and electron effects with a 0.2 A, 1-MeV K + beam. The magnets, originally designed and built for a prototype pulsed magnetic quadrupole array, have an elliptical beam tube (6×10 cm) and iron yoke. The magnet coil and field length are ≈31 cm, and operating gradients are 10-40 T/m. To establish that the field quality of the prototype quadrupoles is satisfactory for the experiments, a 1-cm pickup loop was used to measure the flux Br( θ) at the magnet mid-plane and also at the lead and return ends. A longer probe was used to measure the integrated flux of B θ( θ) along the magnet. The field quality appears satisfactory for the short transport experiments through these quadrupoles.

  18. Quadrupole lattice resonances in plasmonic crystal excited by cylindrical vector beams

    PubMed Central

    Sakai, Kyosuke; Nomura, Kensuke; Yamamoto, Takeaki; Omura, Tatsuya; Sasaki, Keiji

    2016-01-01

    We report a scheme to exploit low radiative loss plasmonic resonance by combining a dark (subradiant) mode and a lattice resonance. We theoretically demonstrate that such dark-mode lattice resonances in periodic arrays of nanodisks or plasmonic crystals can be excited by vertically incident light beams. We investigate the excitation of lattice resonances in a finite sized, square-lattice plasmonic crystal by two types of cylindrical vector beams and a linearly polarized Gaussian beam. Quadrupole lattice resonances are excited by all three beams, and the largest peak intensity is obtained by using a specific type of cylindrical vector beam. Because of their lower radiative losses with many hotspots, the quadrupole lattice resonances in plasmonic crystal may pave the way for photonic research and applications that require strong light-matter interactions. PMID:27734923

  19. Theophylline and warfarin interaction studies with grepafloxacin.

    PubMed

    Efthymiopoulos, C; Bramer, S L; Maroli, A; Blum, B

    1997-01-01

    Two phase I trials, each involving 16 healthy adult volunteers, were performed to investigate possible interactions between grepafloxacin and theophylline or warfarin. In the theophylline study, grepafloxacin 600 mg was administered once daily for 10 days to 12 volunteers who were receiving a maintenance dose of theophylline. This dose of theophylline was designed to produce mean serum theophylline concentrations of 7.5 mg/L; 4 volunteers received theophylline plus placebo. Pharmacokinetic parameters of theophylline were determined before grepafloxacin treatment and on day 10 of grepafloxacin or placebo administration. Peak theophylline concentrations and the area under the concentration-time curve increased significantly during grepafloxacin treatment, and apparent total clearance of theophylline was reduced by approximately 50%. No changes were observed in the placebo group and theophylline appeared to have no effect on the pharmacokinetics of grepafloxacin. In the warfarin study, grepafloxacin 600 mg was given once daily for 14 days to volunteers receiving a maintenance dose of warfarin. Warfarin was discontinued during the last 4 days of grepafloxacin administration. The pharmacodynamics of warfarin did not change after administration of grepafloxacin. Similarly, warfarin had no significant effect on the pharmacokinetics of grepafloxacin. We conclude that during treatment with grepafloxacin maintenance, doses of theophylline should be reduced by 50%, and we recommend that serum concentrations of theophylline be monitored during treatment with grepafloxacin. However, no dose adjustment is necessary for grepafloxacin when it is coadministered with theophylline, and dose adjustment does not seem to be required in concomitant treatment with grepafloxacin and warfarin.

  20. Study made of interaction between sound fields and structural vibrations

    NASA Technical Reports Server (NTRS)

    Lyon, R. H.; Smith, P. W., Jr.

    1967-01-01

    Study analyzes structural vibrations and the interactions between them and sound fields. It outlines a conceptual framework to analyze the vibrations of systems and their interactions, incorporating the results of earlier studies and establishing a unified basis for continuing research.

  1. Distal and proximal ligand interactions in heme proteins: correlations between C-O and Fe-C vibrational frequencies, oxygen-17 and carbon-13 nuclear magnetic resonance chemical shifts, and oxygen-17 nuclear quadrupole coupling constants in C17O- and 13CO-labeled species.

    PubMed

    Park, K D; Guo, K M; Adebodun, F; Chiu, M L; Sligar, S G; Oldfield, E

    1991-03-05

    We have obtained the oxygen-17 nuclear magnetic resonance (NMR) spectra of a variety of C17O-labeled heme proteins, including sperm whale (Physeter catodon) myoglobin, two synthetic sperm whale myoglobin mutants (His E7----Val E7; His E7----Phe E7), adult human hemoglobin, rabbit (Oryctolagus cuniculus) hemoglobin, horseradish (Cochlearia armoracia) peroxidase (E.C. 1.11.1.7) isoenzymes A and C, and Caldariomyces fumago chloroperoxidase (E.C. 1.11.1.10), in some cases as a function of pH, and have determined their isotropic 17O NMR chemical shifts, delta i, and spin-lattice relaxation times, T1. We have also obtained similar results on a picket fence prophyrin, [5,10,15,20-tetrakis(alpha, alpha, alpha, alpha, alpha-pivalamidophenyl)porphyrinato]iron(II) (1-MeIm)CO, both in solution and in the solid state. Our results show an excellent correlation between the infrared C-O vibrational frequencies, v(C-O), and delta i, between v(C-O) and the 17O nuclear quadrupole coupling constant (e2qQ/h, derived from T1), and as expected between e2qQ/h and delta i. Taken together with the work of others on the 13C NMR of 13CO-labeled proteins, where we find an excellent correlation between delta i(13C) and v(Fe-C), our results suggest that IR and NMR measurements reflect the same interaction, which is thought to be primarily the degree of pi-back-bonding from Fe d to CO pi* orbitals, as outlined previously [Li, X.-Y., & Spiro, T.G. (1988) J. Am. Chem. Soc. 110, 6024]. The modulation of this interaction by the local charge field of the distal heme residue (histidine, glutamine, arginine, and possibly lysine) in a variety of species and mutants, as reflected in the NMR and IR measurements, is discussed, as is the effect of cysteine as the proximal heme ligand.

  2. Development of Superconducting Focusing Quadrupoles for Heavy Ion Drivers

    SciTech Connect

    Martovetsky, N; Manahan, R; Lietzke, A F

    2001-09-10

    Heavy Ion Fusion (HIF) is exploring a promising path to a practical inertial-confinement fusion reactor. The associated heavy ion driver will require a large number of focusing quadrupole magnets. A concept for a superconducting quadrupole array, using many simple racetrack coils, was developed at LLNL. Two, single-bore quadrupole prototypes of the same design, with distinctly different conductor, were designed, built, and tested. Both prototypes reached their short sample currents with little or no training. Magnet design, and test results, are presented and discussed.

  3. Solid state proton imaging detected by quadrupole resonance.

    PubMed

    Perlo, J; Casanova, F; Robert, H; Pusiol, D J

    2001-06-01

    A double resonance method for imaging of solid materials containing quadrupole nuclei via the coupled protons is reported. The technique uses a static field gradient to encode the position on the protons and the method of double resonance spin-echo to detect the occurrence of proton resonances by affecting the zero-field echo signal from the quadrupole system. The double resonance imaging method offers the advantages of higher spatial resolution and straightforward image reconstruction for powder samples compared with rotating-frame and Zeeman-perturbated nuclear quadrupole resonance encoding techniques. Copyright 2001 Academic Press.

  4. Acoustic monopoles, dipoles, and quadrupoles: An experiment revisited

    NASA Astrophysics Data System (ADS)

    Russell, Daniel A.; Titlow, Joseph P.; Bemmen, Ya-Juan

    1999-08-01

    A simple and inexpensive demonstration of acoustic monopole, dipole, and quadrupole sources utilizes four 4-in. boxed loudspeakers and a homemade switch box. The switch box allows the speakers to be driven in any combination of phase relationships. Placing the speakers on a rotating stool allows students to measure directivity patterns for monopole, dipole, and quadrupole speaker combinations. Stacking the speakers in a square, all facing the same direction, allows students to aurally compare the frequency and amplitude dependence of sound radiation from monopoles, dipoles, and quadrupoles.

  5. Emission of nuclear quadrupole resonance from polycrystalline hexamethylenetetramine.

    PubMed

    Ota, G; Itozaki, H

    2008-03-01

    The angular dependence of the nuclear quadrupole resonance (NQR) signal intensity emitted from polycrystalline hexamethylenetetramine has been analytically investigated for all directions for non-contact detection of chemicals by nuclear quadrupole resonance. The field pattern of the NQR signal from a column sample was measured. The emitted patterns were the same as that from a united single magnetic dipole, which fitted well to the estimation based on quadrupole principle axis system. This result is helpful to design an antenna for NQR remote detection.

  6. NUCLEAR QUADRUPOLE INTERACTION IN CRYSTALS BY THE MOSSBAUER EFFECT.

    DTIC Science & Technology

    The Mossbauer effect following Coulomb excitation by 3.3-MeV alpha particles has been observed in Dy-161 and Eu-151. Both the 43.8-keV state in Dy...microcrystals. Both in bulk and microcrystal hematite no evidence has been found for a gradual Morin spin-flip transition. (Author)

  7. Machine detector interface studies: Layout and synchrotron radiation estimate in the future circular collider interaction region

    NASA Astrophysics Data System (ADS)

    Boscolo, Manuela; Burkhardt, Helmut; Sullivan, Michael

    2017-01-01

    The interaction region layout for the e+e- future circular collider FCC-ee is presented together with a preliminary estimate of synchrotron radiation that affects this region. We describe in this paper the main guidelines of this design and the estimate of synchrotron radiation coming from the last bending magnets and from the final focus quadrupoles, with the software tools developed for this purpose. The design follows the asymmetric optics layout as far as incoming bend radiation is concerned with the maximum foreseen beam energy of 175 GeV and we present a feasible initial layout with an indication of tolerable synchrotron radiation.

  8. Multiple parton interaction studies at DØ

    DOE PAGES

    Lincoln, D.

    2016-04-01

    Here, we present the results of studies of multiparton interactions done by the DØ collaboration using the Fermilab Tevatron at a center of mass energy of 1.96 TeV. We also present three analyses, involving three distinct final signatures: (a) a photon with at least 3 jets ( γ + 3jets), (b) a photon with a bottom or charm quark tagged jet and at least 2 other jets ( γ + b/c + 2jets), and (c) two J/ ψ mesons. The fraction of photon + jet events initiated by double parton scattering is about 20%, while the fraction for events inmore » which two J/ ψ mesons were produced is 30 ± 10. While the two measurements are statistically compatible, the difference might indicate differences in the quark and gluon distribution within a nucleon. Finally, this speculation originates from the fact that photon + jet events are created by collisions with quarks in the initial states, while J/ ψ events are produced preferentially by a gluonic initial state.« less

  9. Multiple parton interaction studies at DØ

    SciTech Connect

    Lincoln, D.

    2016-04-01

    Here, we present the results of studies of multiparton interactions done by the DØ collaboration using the Fermilab Tevatron at a center of mass energy of 1.96 TeV. We also present three analyses, involving three distinct final signatures: (a) a photon with at least 3 jets ( γ + 3jets), (b) a photon with a bottom or charm quark tagged jet and at least 2 other jets ( γ + b/c + 2jets), and (c) two J/ ψ mesons. The fraction of photon + jet events initiated by double parton scattering is about 20%, while the fraction for events in which two J/ ψ mesons were produced is 30 ± 10. While the two measurements are statistically compatible, the difference might indicate differences in the quark and gluon distribution within a nucleon. Finally, this speculation originates from the fact that photon + jet events are created by collisions with quarks in the initial states, while J/ ψ events are produced preferentially by a gluonic initial state.

  10. Studies of host graft interactions in vitro

    NASA Astrophysics Data System (ADS)

    Liljekvist-Larsson, Ingela; Johansson, Kjell

    2007-09-01

    Progenitor and stem cell transplantation represent therapeutic strategies for retinal disorders that are accompanied by photoreceptor degeneration. The transplanted cells may either replace degenerating photoreceptors or secrete beneficial factors that halt the processes of photoreceptor degeneration. The present study analyzes whether rat retinal progenitor cells differentiated into photoreceptor phenotypic cells in neurospheres have a potential to interact with rat retinal explants. Immunocytochemistry for rhodopsin and synaptophysin indicated photoreceptor cell-like differentiation in neurospheres that were stimulated by basic fibroblast growth factor and epidermal growth factor. Differentiation into neural phenotypes including photoreceptor cells was effectively blocked by an addition of leukemia inhibitory factor. Grafting of neurospheres onto retinal explants demonstrated a consistent penetration of glial cell processes into the explanted tissue. On the other hand, the incorporation of donor cells into explants was very low. A general finding was that neurospheres grafting was associated with local decrease in Müller cell activation in the explants. Further characterization of these effect(s) could provide further insight into progenitor cell-based therapies of retinal degenerative disorders.

  11. Study of electron and neutrino interactions

    SciTech Connect

    Abashian, A.

    1997-03-18

    This is the final report for the DOE-sponsored experimental particle physics program at Virginia Tech to study the properties of the Standard Model of strong and electroweak interactions. This contract (DE-AS05-80ER10713) covers the period from August 1, 1980 to January 31, 1993. Task B of this contract, headed by Professor Alexander Abashian, is described in this final report. This program has been pursued on many fronts by the researchers-in a search for axions at SLAC, in electron-positron collisions in the AMY experiment at the TRISTAN collider in Japan, in measurements of muon decay properties in the MEGA and RHO experiments at the LAMPF accelerator, in a detailed analysis of scattering effects in the purported observation of a 17 keV neutrino at Oxford, in a search for a disoriented chiral condensate with the MiniMax experiment at Fermilab, and in an R&D program on resistive plate counters that could find use in low-cost high-quality charged particle detection at low rates.

  12. {sup 63}Cu(2) nuclear quadrupole and nuclear magnetic resonance studies of YBa{sub 2}Cu{sub 4}O{sub 8} in the normal and superconducting states

    SciTech Connect

    Corey, R.L.; Curro, N.J.; OHara, K.; Imai, T.; Slichter, C.P.; Yoshimura, K.; Katoh, M.; Kosuge, K.

    1996-03-01

    We report nuclear quadrupole resonance (NQR) and nuclear magnetic resonance (NMR) measurements of the spin lattice and Gaussian spin-spin relaxation times, {ital T}{sub 1} and {ital T}{sub 2{ital G}}, respectively, in an unaligned (NQR) and aligned (NMR) powder of YBa{sub 2}Cu{sub 4}O{sub 8}. Experimental details, critical for accurate NQR measurements in this system, are discussed. The normal-state data are analyzed using several models. Evidence for the existence of a spin gap is presented. The normal-state data agree well with an analysis using scaling theory predictions for {ital z}=1 quantum critical and quantum disordered regimes. The superconducting state data agree with recent calculations for {ital d}-wave superconductivity. {copyright} {ital 1996 The American Physical Society.}

  13. Beam based alignment of C-shaped quadrupole magnets

    SciTech Connect

    Portmann, G.; Robin, D.

    1998-06-01

    Many storage rings have implemented a method of finding the positional offset between the electrical center of the beam position monitors (BPM) and the magnetic center of the adjacent quadrupole magnets. The algorithm for accomplishing this is usually based on modulating the current in the quadrupole magnet and finding the beam position that minimizes the orbit perturbation. When the quadrupole magnet is C-shaped, as it is for many light sources, the modulation method can produce an erroneous measurement of the magnetic center in the horizontal plane. When the current in a C-shaped quadrupole is changed, there is an additional dipole component in the vertical field. Due to nonlinearities in the hysteresis cycle of the C-magnet geometry, the beam-based alignment technique at the Advanced Light Source (ALS) deviated horizontally by .5 mm from the actual magnetic center. By modifying the technique, the offsets were measured to an accuracy of better than 50 {micro}m.

  14. PRINCIPLE OF SKEW QUADRUPOLE MODULATION TO MEASURE BETATRON COUPLING.

    SciTech Connect

    LUO.Y.PILAT,F.ROSER,T.ET AL.

    2004-07-05

    The measurement of the residual betatron coupling via skew quadrupole modulation is a new diagnostics technique that has been developed and tested at the Relativistic Heavy Ion Collider (RHIC) as a very promising method for the linear decoupling on the ramp. By modulating the strengths of different skew quadrupole families the two eigentunes are precisely measured with the phase lock loop system. The projections of the residual coupling coefficient onto the skew quadrupole coupling modulation directions are determined. The residual linear coupling could be corrected according to the measurement. An analytical solution for skew quadrupole modulation based on Hamiltonian perturbation approximation is given, and simulation code using smooth accelerator model is also developed. Some issues concerning the practical applications of this technique are discussed.

  15. Electro-Magnetic Quadrupole Magnets in the LCLS FEL Undulator

    SciTech Connect

    Emma, P.

    2005-01-31

    We discuss various aspects of electro-magnetic quadrupole (EMQ) magnets for the LCLS FEL undulator, including their utility in beam-based alignment (BBA), magnet design issues, and impact on tunnel environment, reliability, and cost.

  16. Quadrupole electromagnetic radiation of an oscillating charged droplet

    NASA Astrophysics Data System (ADS)

    Grigor'ev, A. I.; Kolbneva, N. Yu.; Shiryaeva, S. O.

    2017-06-01

    Analytical calculations using the first order of smallness with respect to dimensionless amplitude of oscillations show that the intensity of electromagnetic radiation of a charged droplet is determined by time-dependent quadrupole moment.

  17. Two experimental case studies of interacting swash events: a strong interaction and a weak interaction

    NASA Astrophysics Data System (ADS)

    Pujara, N.; Liu, P. L. F.

    2016-12-01

    The swash zone - the subregion of the nearshore that is periodically covered by flowing water due to waves - is an important, dynamic area for sediment transport and beach morphology. On natural beaches successive swash events and their mutual interactions are commonplace, which may lead to enhanced sediment transport and wave run-up. We present measurements of bed shear stress, bed pressure, and free-surface displacement from large-scale experiments to understand the dynamics of the boundary layer during swash interactions. We find that the dimensionless swash period, i.e., the ratio of the time period of swash to the time separation of successive wave crests, plays an important role in determining qualitative character of the swash-swash interaction. We also link this dimensionless swash period to the wave breaker type through the surf similarity parameter, providing a way to predict the qualitative behaviour of swash interactions from limited knowledge of incident waves.

  18. A systematic study on hydrogen bond interactions in sulfabenzamide: DFT calculations of the N-14, O-17, and H-2 NQR parameters.

    PubMed

    Nozad, Ahmad G; Najafi, Hamidreza; Meftah, Sakineh; Aghazadeh, Mustafa

    2009-02-01

    A systematic computational study was carried out to characterize the hydrogen bond, HB, interactions of sulfabenzamide crystal structure by DFT calculations of electric field gradient, EFG, tensors at the sites of 14N, 17O, and 2H nuclei. The computations were performed with the B3LYP and B3PW91 DFT methods and 6-311+G and 6-311++G* standard basis sets using the Gaussian 98 package. To perform the calculations, a hydrogen-bonded heptameric cluster of sulfabenzamide was created by X-ray coordinates where the hydrogen atom positions were optimized and the EFG tensors were calculated for the target molecule. Additional optimization and EFG calculations were also performed for crystalline monomer and an isolated gas-phase sulfabenzamide. The calculated EFG tensors were converted to the experimentally measurable nuclear quadrupole resonance, NQR, parameters: quadrupole coupling constant, C(Q), and asymmetry parameter, eta(Q). The results reveal that the geometrical and NQR parameters of the optimized isolated gas-phase and crystalline phase are different. In addition, the difference between the calculated NQR parameters of the monomer and the target molecule shows how much H-bonding interactions affect the EFG tensors of each nucleus. The evaluated NQR parameters reveal that due to the contribution of the target molecule to N-H...O and C-H...O hydrogen bond interactions, the EFG tensors at the sites of N1, O3 and H1 undergo significant changes from monomer to the target molecule in cluster. These features reveal the major role of N-H...O type intermolecular HBs in cluster model of sulfabenzamide which the presence of these interactions can lead to polymorphism directly related to the drug activity and related properties.

  19. Translationally invariant semi-classical electrodynamics of magnetic media to electric octopole-magnetic quadrupole order

    NASA Astrophysics Data System (ADS)

    Welter, A.; Raab, R. E.; de Lange, O. L.

    2013-02-01

    We consider semi-classical macroscopic electrodynamics that is translationally invariant (independent of the choice of an arbitrary, implicit set of coordinate origins for molecule-fixed axes) for linear, homogeneous, anisotropic media interacting with harmonic, plane electromagnetic waves. We extend a previous formulation at electric octopole-magnetic quadrupole order to include media comprising magnetic molecules (those possessing both time-even and time-odd properties). This requires two additional invariant, time-odd molecular polarizabilities. Overall, the electrodynamics depends on 10 invariant polarizabilities—5 time even (one each of electric dipole and electric quadrupole-magnetic dipole order, and three of electric octopole-magnetic quadrupole order) and 5 time odd (one, two, and two, respectively)—that are required for the description of linear transmission and reflection phenomena, and material constants. The two additional time-odd polarizabilities account for certain predicted effects, and one of them contributes to the inverse ac permeability of magnetic media. The results are presented in a form that is suitable for numerical computation.

  20. Quadrupole second harmonic generation and sum-frequency generation in ZnO quantum dots

    SciTech Connect

    Maikhuri, Deepti; Purohit, S. P. Mathur, K. C.

    2015-04-15

    The second harmonic generation (SHG) and the sum frequency generation (SFG) processes are investigated in the conduction band states of the singly charged ZnO quantum dot (QD) embedded in the HfO{sub 2}, and the AlN matrices. With two optical fields of frequency ω{sub p} and ω{sub q} incident on the dot, we study the variation with frequency of the second order nonlinear polarization resulting in SHG and SFG, through the electric dipole and the electric quadrupole interactions of the pump fields with the electron in the dot. We obtain enhanced value of the second order nonlinear susceptibility in the dot compared to the bulk. The effective mass approximation with the finite confining barrier is used for obtaining the energy and wavefunctions of the quantized confined states of the electron in the conduction band of the dot. Our results show that both the SHG and SFG processes depend on the dot size, the surrounding matrix and the polarization states of the pump beams.

  1. Experimental implementation of quantum information processing by Zeeman-perturbed nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Teles, João; Rivera-Ascona, Christian; Polli, Roberson S.; Oliveira-Silva, Rodrigo; Vidoto, Edson L. G.; Andreeta, José P.; Bonagamba, Tito J.

    2015-06-01

    Nuclear magnetic resonance (NMR) has been widely used in the context of quantum information processing (QIP). However, despite the great similarities between NMR and nuclear quadrupole resonance (NQR), no experimental implementation for QIP using NQR has been reported. We describe the implementation of basic quantum gates and their applications on the creation and manipulation of pseudopure states using linearly polarized radiofrequency pulses under static magnetic field perturbation. The NQR quantum operations were implemented using a single-crystal sample of and observing nuclei, which possess spin 3/2 and give rise to a two-qubit system. The results are very promising and indicate that NQR can be successfully used for performing fundamental experiments in QIP. One advantage of NQR in comparison with NMR is that the main interaction is internal to the sample, which makes the system more compact, lowering its cost and making it easier to be miniaturized to solid-state devices. Furthermore, as an example, the study of squeezed spin states could receive relevant contributions from NQR.

  2. Thermal Analysis of the ILC Superconductin Quadrupole

    SciTech Connect

    Ross, Ian; /Rose-Hulman Inst., Terre Haute /SLAC

    2006-09-13

    Critical to a particle accelerator's functioning, superconducting magnets serve to focus and aim the particle beam. The Stanford Linear Accelerator Center (SLAC) has received a prototype superconducting quadrupole designed and built by the Centro de Investigaciones Energ{acute e}ticas, Medioambientales y Tecnol{acute o}gicas (CIEMAT) to be evaluated for the International Linear Collider (ILC) project. To ensure proper functioning of the magnet, the device must be maintained at cryogenic temperatures by use of a cooling system containing liquid nitrogen and liquid helium. The cool down period of a low temperature cryostat is critical to the success of an experiment, especially a prototype setup such as this one. The magnet and the dewar each contain unique heat leaks and material properties. These differences can lead to tremendous thermal stresses. The system was analyzed mathematically, leading to ideal liquid helium and liquid nitrogen flow rates during the magnet's cool-down to 4.2 K, along with a reasonable estimate of how long this cool-down will take. With a flow rate of ten gaseous liters of liquid nitrogen per minute, the nitrogen shield will take approximately five hours to cool down to 77 K. With a gaseous helium flow rate of sixty liters per minute, the magnet will take at least nineteen hours to cool down to a temperature of 4.2 K.

  3. Adjustable rare earth quadrupole drift tube magnets

    SciTech Connect

    Feinberg, B.; Tanabe, J.; Halbach, K.; Koehler, G.; Green, M.I.

    1987-03-01

    A prototype permanent-magnet drift tube quadrupole with adjustable field strength has been constructed and tested. The magnet uses iron pole pieces to provide the required field shape along with rare earth permanent-magnet material (samarium cobalt) to energize the magnet. A unique feature of the configuration is the adjustability of the field, accomplished by rotating the outer rings consisting of permanent magnets and iron. In contrast with a previous prototype magnet, this new design uses ball bearings in place of slide bearings to eliminate potential failures. The rotation is now achieved with a bevel gear mechanism. The prototype design also incorporates a new drift tube shell vacuum seal to allow easy disassembly. Tests were made of the magnetic properties and the mechanical performance of this magnet. Field errors are extremely small, and the magnet passed an accelerated ten year lifetime test. It is planned to use this type of magnet to replace 24 of the SuperHILAC prestripper drift tubes.

  4. A theoretical study on the characteristics of the intermolecular interactions in the active site of human androsterone sulphotransferase: DFT calculations of NQR and NMR parameters and QTAIM analysis.

    PubMed

    Astani, Elahe K; Heshmati, Emran; Chen, Chun-Jung; Hadipour, Nasser L

    2016-07-01

    A theoretical study at the level of density functional theory (DFT) was performed to characterize noncovalent intermolecular interactions, especially hydrogen bond interactions, in the active site of enzyme human androsterone sulphotransferase (SULT2A1/ADT). Geometry optimization, interaction energy, (2)H, (14)N, and (17)O electric field gradient (EFG) tensors, (1)H, (13)C, (17)O, and (15)N chemical shielding (CS) tensors, Natural Bonding Orbital (NBO) analysis, and quantum theory of atoms in molecules (QTAIM) analysis of this active site were investigated. It was found that androsterone (ADT) is able to form hydrogen bonds with residues Ser80, Ile82, and His99 of the active site. The interaction energy calculations and NBO analysis revealed that the ADT molecule forms the strongest hydrogen bond with Ser80. Results revealed that ADT interacts with the other residues through electrostatic and Van der Waals interactions. Results showed that these hydrogen bonds influence on the calculated (2)H, (14)N, and (17)O quadrupole coupling constants (QCCs), as well as (1)H, (13)C, (17)O, and (15)N CS tensors. The magnitude of the QCC and CS changes at each nucleus depends directly on its amount of contribution to the hydrogen bond interaction. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Development of electrostatic quadrupoles for heavy ion fusion

    SciTech Connect

    Faltens, A.; Seidl, P.

    1996-03-01

    High-voltage electrostatic quadrupoles are used for focusing ion beams at low energies in the induction linac approach to heavy ion driven inertial confinement fusion for the production of electrical power. The transportable beam line charge density depends linearly on the operating voltage of the quadrupoles, so an experimental program was conducted to find the voltage break-down dependence on the overall size of the quadrupoles which would then allow determination of the best geometry and operating voltage. The quadrupole electrodes are usually stainless steel cylinders with hemispherical end caps, mounted on stainless steel end plates. The end plates are precisely positioned with respect to each other and the vacuum chamber with alumina insulators with shielded triple points. It is advantageous for beam transport to employ an array of multiple beams for which a rather large number of interdigitated electrodes forms an array of quadrupoles. The trade-offs between very large numbers of small channels and a smaller number of large channels, and the dependence of the choice on the voltage break-down dependence is discussed. With present understanding, the optimum is about 100 beamlets focused with quadrupoles which have a beam aperture radius of about 2.3 cm and are operated with about 150 kV between electrodes.

  6. Parametric study of transport beam lines for electron beams accelerated by laser-plasma interaction

    SciTech Connect

    Scisciò, M.; Antici, P.; Lancia, L.; Migliorati, M.; Mostacci, A.; Palumbo, L.; Papaphilippou, Y.

    2016-03-07

    In the last decade, laser-plasma acceleration of high-energy electrons has attracted strong attention in different fields. Electrons with maximum energies in the GeV range can be laser-accelerated within a few cm using multi-hundreds terawatt (TW) lasers, yielding to very high beam currents at the source (electron bunches with up to tens-hundreds of pC in a few fs). While initially the challenge was to increase the maximum achievable electron energy, today strong effort is put in the control and usability of these laser-generated beams that still lack of some features in order to be used for applications where currently conventional, radio-frequency (RF) based, electron beam lines represent the most common and efficient solution. Several improvements have been suggested for this purpose, some of them acting directly on the plasma source, some using beam shaping tools located downstream. Concerning the latter, several studies have suggested the use of conventional accelerator magnetic devices (such as quadrupoles and solenoids) as an easy implementable solution when the laser-plasma accelerated beam requires optimization. In this paper, we report on a parametric study related to the transport of electron beams accelerated by laser-plasma interaction, using conventional accelerator elements and tools. We focus on both, high energy electron beams in the GeV range, as produced on petawatt (PW) class laser systems, and on lower energy electron beams in the hundreds of MeV range, as nowadays routinely obtained on commercially available multi-hundred TW laser systems. For both scenarios, our study allows understanding what are the crucial parameters that enable laser-plasma accelerators to compete with conventional ones and allow for a beam transport. We show that suitable working points require a tradeoff-combination between low beam divergence and narrow energy spread.

  7. Parametric study of transport beam lines for electron beams accelerated by laser-plasma interaction

    NASA Astrophysics Data System (ADS)

    Scisciò, M.; Lancia, L.; Migliorati, M.; Mostacci, A.; Palumbo, L.; Papaphilippou, Y.; Antici, P.

    2016-03-01

    In the last decade, laser-plasma acceleration of high-energy electrons has attracted strong attention in different fields. Electrons with maximum energies in the GeV range can be laser-accelerated within a few cm using multi-hundreds terawatt (TW) lasers, yielding to very high beam currents at the source (electron bunches with up to tens-hundreds of pC in a few fs). While initially the challenge was to increase the maximum achievable electron energy, today strong effort is put in the control and usability of these laser-generated beams that still lack of some features in order to be used for applications where currently conventional, radio-frequency (RF) based, electron beam lines represent the most common and efficient solution. Several improvements have been suggested for this purpose, some of them acting directly on the plasma source, some using beam shaping tools located downstream. Concerning the latter, several studies have suggested the use of conventional accelerator magnetic devices (such as quadrupoles and solenoids) as an easy implementable solution when the laser-plasma accelerated beam requires optimization. In this paper, we report on a parametric study related to the transport of electron beams accelerated by laser-plasma interaction, using conventional accelerator elements and tools. We focus on both, high energy electron beams in the GeV range, as produced on petawatt (PW) class laser systems, and on lower energy electron beams in the hundreds of MeV range, as nowadays routinely obtained on commercially available multi-hundred TW laser systems. For both scenarios, our study allows understanding what are the crucial parameters that enable laser-plasma accelerators to compete with conventional ones and allow for a beam transport. We show that suitable working points require a tradeoff-combination between low beam divergence and narrow energy spread.

  8. Space Shuttle interactive meteorological data system study

    NASA Technical Reports Server (NTRS)

    Young, J. T.; Fox, R. J.; Benson, J. M.; Rueden, J. P.; Oehlkers, R. A.

    1985-01-01

    Although focused toward the operational meteorological support review and definition of an operational meteorological interactive data display systems (MIDDS) requirements for the Space Meteorology Support Group at NASA/Johnson Space Center, the total operational meteorological support requirements and a systems concept for the MIDDS network integration of NASA and Air Force elements to support the National Space Transportation System are also addressed.

  9. Interactive social neuroscience to study autism spectrum disorder.

    PubMed

    Rolison, Max J; Naples, Adam J; McPartland, James C

    2015-03-01

    Individuals with autism spectrum disorder (ASD) demonstrate difficulty with social interactions and relationships, but the neural mechanisms underlying these difficulties remain largely unknown. While social difficulties in ASD are most apparent in the context of interactions with other people, most neuroscience research investigating ASD have provided limited insight into the complex dynamics of these interactions. The development of novel, innovative "interactive social neuroscience" methods to study the brain in contexts with two interacting humans is a necessary advance for ASD research. Studies applying an interactive neuroscience approach to study two brains engaging with one another have revealed significant differences in neural processes during interaction compared to observation in brain regions that are implicated in the neuropathology of ASD. Interactive social neuroscience methods are crucial in clarifying the mechanisms underlying the social and communication deficits that characterize ASD.

  10. Fabrication and test of 4m long Nb3Sn quadrupole coil made of RRP-114-127 strand

    SciTech Connect

    Bossert, R.; Ambrosio, G.; Andreev, N.; Barzi, E.; Chlachidze, G.; Kashikhin, V.V.; Lamm, M.; Nobrega, A.; Novitski, I.; Orris, D.; Tartaglia, M.; /Fermilab

    2011-06-01

    Fermilab is collaborating with LBNL and BNL (US-LARP collaboration) to develop a large-aperture Nb{sub 3}Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade. Several two-layer quadrupole models of the 1-meter and 3.4-meter length with 90mm apertures have been fabricated and tested by the US-LARP collaboration. High-Jc RRP-54/61 strand was used for nearly all models. Large flux jumps typical for this strand due to the large sub-element diameter limited magnet quench performance at temperatures below 2.5-3K. This paper summarizes the fabrication and test by Fermilab of LQM01, a long quadrupole coil test structure (quadrupole mirror) with the first 3.4m quadrupole coil made of more stable RRP-114/127 strand. The coil and structure are fully instrumented with voltage taps, full bridge strain gauges and strip heaters to monitor preload, thermal properties and quench behavior. Measurements during fabrication are reported, including preload during the yoke welding process. Testing is done at 4.5K, 1.9K and a range of intermediate temperatures. The test results include magnet strain and quench performance during training, as well as quench studies of current ramp rate and temperature dependence from 1.9K to 4.5K.

  11. CFD Modelling of a Quadrupole Vortex Inside a Cylindrical Channel for Research into Advanced Hybrid Rocket Designs

    NASA Astrophysics Data System (ADS)

    Godfrey, B.; Majdalani, J.

    2014-11-01

    This study relies on computational fluid dynamics (CFD) tools to analyse a possible method for creating a stable quadrupole vortex within a simulated, circular-port, cylindrical rocket chamber. A model of the vortex generator is created in a SolidWorks CAD program and then the grid is generated using the Pointwise mesh generation software. The non-reactive flowfield is simulated using an open source computational program, Stanford University Unstructured (SU2). Subsequent analysis and visualization are performed using ParaView. The vortex generation approach that we employ consists of four tangentially injected monopole vortex generators that are arranged symmetrically with respect to the center of the chamber in such a way to produce a quadrupole vortex with a common downwash. The present investigation focuses on characterizing the flow dynamics so that future investigations can be undertaken with increasing levels of complexity. Our CFD simulations help to elucidate the onset of vortex filaments within the monopole tubes, and the evolution of quadrupole vortices downstream of the injection faceplate. Our results indicate that the quadrupole vortices produced using the present injection pattern can become quickly unstable to the extent of dissipating soon after being introduced into simulated rocket chamber. We conclude that a change in the geometrical configuration will be necessary to produce more stable quadrupoles.

  12. Fabrication and test of 4M long Nb3SN quadrupole coil made of RRP-114/127 strand

    NASA Astrophysics Data System (ADS)

    Bossert, Rodger; Ambrosio, G.; Andreev, Nikolai; Barzi, Emanuela; Chlachidze, Guram; Kashikhin, Vadim; Lamm, Michael; Nobrega, Alfred; Novitski, Igor; Orris, Darryl; Tartaglia, Mike; Turrioni, Daniele; Yamada, Ryuji; Zlobin, Alexander

    2012-06-01

    Fermilab is collaborating with Lawrence Berkeley National Laboratory (LBNL) and Brookhaven National Laboratory (BNL) within the US-LHC Accelerator Research Project (US-LARP collaboration) to develop a large-aperture Nb3SN superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade. Several two-layer quadrupole models of the 1-meter and 3.4-meter length with 90 mm apertures have been fabricated and tested by the US-LARP collaboration. High-Jc Nb3SN RRP-54/61 strand was used for nearly all models. Large flux jumps typical for this strand, due to the large sub-element diameter, limited magnet quench performance at temperatures below 2.5-3K. This paper summarizes the fabrication and test by Fermilab of LQM01, a long quadrupole coil test structure (quadrupole mirror) with the first 3.4 m quadrupole coil made of more stable RRP-114/127 strand. The coil and structure are fully instrumented with voltage taps, full bridge strain gauges and strip heaters to monitor preload, thermal properties and quench behavior. Measurements during fabrication are reported, including preload during the yoke welding process. Testing is done at 4.5 K, 1.9 K and a range of intermediate temperatures. The test results include magnet strain and quench performance during training, as well as quench studies of current ramp rate and temperature dependence from 1.9 K to 4.5 K.

  13. Ionosphere/microwave beam interaction study

    NASA Technical Reports Server (NTRS)

    Gordon, W. E.; Duncan, L. M.

    1978-01-01

    The microwave beam of the Solar Power Satellite (SPS) is predicted to interact with the ionosphere producing thermal runaway up to an altitude of about 100 kilometers at a power density threshold of 12 mW/cm sq (within a factor of two). The operation of the SPS at two frequencies, 2450 and 5800 MHz, is compared. The ionosphere interaction is less at the higher frequency, but the tropospheric problem scattering from heavy rain and hail is worse at the higher frequency. Microwave signals from communication satellites were observed to scintillate, but there is some concern that the uplink pilot signal may be distorted by the SPS heated ionosphere. The microwave scintillations are only observed in the tropics in the early evenings near the equinoxes. Results indicate that large phase errors in the uplink pilot signal can be reduced.

  14. Aerodynamic sound generation due to vortex-aerofoil interaction. Part 2: Analysis of the acoustic field

    NASA Technical Reports Server (NTRS)

    Parasarathy, R.; Karamcheti, K.

    1972-01-01

    The Lighthill method was the basic procedure used to analyze the sound field associated with a vortex of modified strength interacting with an airfoil. A free vortex interacting with an airfoil in uniform motion was modeled in order to determine the sound field due to all the acoustic sources, not only on the airfoil surfaces (dipoles), but also the ones distributed on the perturbed flow field (quadrupoles) due to the vortex-airfoil interaction. Because inviscid flow is assumed in the study of the interaction, the quadrupoles considered in the perturbed flow field are entirely due to an unsteady flow field. The effects of airfoil thickness on the second radiation are examined by using a symmetric Joukowski airfoil for the vortex-airfoil interaction. Sound radiation in a plane, far field simplification, and computation of the sound field are discussed.

  15. A global hybrid model for Mercury's interaction with the solar wind: Case study of the dipole representation

    NASA Astrophysics Data System (ADS)

    Richer, E.; Modolo, R.; Chanteur, G. M.; Hess, S.; Leblanc, F.

    2012-10-01

    The interaction of the solar wind (SW) with the magnetic field of Mercury is investigated by means of a three dimensional parallelized multispecies hybrid model. A comparison between two mathematical representations of Mercury's intrinsic magnetic field is studied. The first model is an Offset Dipole (OD) having the offset and dipolar moment reported by Anderson et al. (2011). The second model is a combination of a Dipole and a Quadrupole (DQ), the total field is fitted to the offset dipolar field, for northern latitudes greater than 50°. Simulations reproduce the features which characterize Mercury's interaction with the SW, encompassing the Bow Shock (BS), the magnetosheath, the magnetotail, the “cusps” region and the neutral current sheet. Global hybrid simulations of the Hermean magnetosphere run for the OD and DQ models demonstrate that the southern parts of the magnetospheres produced by the OD and DQ models differ greatly in topology and volume meanwhile their northern parts-are quite similar. In particular the DQ model exhibits a dome of closed field lines around the south pole in contrast to the OD. Without further information on the intrinsic magnetic field of the planet in the southern region which should be provided by BepiColombo after year 2020, we can only speculate on the influence of the different magnetic topologies on the magnetospheric dynamics.

  16. Microfluidic Devices for Studying Biomolecular Interactions

    NASA Technical Reports Server (NTRS)

    Wilson, Wilbur W.; Garcia, Carlos d.; Henry, Charles S.

    2006-01-01

    Microfluidic devices for monitoring biomolecular interactions have been invented. These devices are basically highly miniaturized liquid-chromatography columns. They are intended to be prototypes of miniature analytical devices of the laboratory on a chip type that could be fabricated rapidly and inexpensively and that, because of their small sizes, would yield analytical results from very small amounts of expensive analytes (typically, proteins). Other advantages to be gained by this scaling down of liquid-chromatography columns may include increases in resolution and speed, decreases in the consumption of reagents, and the possibility of performing multiple simultaneous and highly integrated analyses by use of multiple devices of this type, each possibly containing multiple parallel analytical microchannels. The principle of operation is the same as that of a macroscopic liquid-chromatography column: The column is a channel packed with particles, upon which are immobilized molecules of the protein of interest (or one of the proteins of interest if there are more than one). Starting at a known time, a solution or suspension containing molecules of the protein or other substance of interest is pumped into the channel at its inlet. The liquid emerging from the outlet of the channel is monitored to detect the molecules of the dissolved or suspended substance(s). The time that it takes these molecules to flow from the inlet to the outlet is a measure of the degree of interaction between the immobilized and the dissolved or suspended molecules. Depending on the precise natures of the molecules, this measure can be used for diverse purposes: examples include screening for solution conditions that favor crystallization of proteins, screening for interactions between drugs and proteins, and determining the functions of biomolecules.

  17. Strong Interaction Studies with PANDA at FAIR

    NASA Astrophysics Data System (ADS)

    Schönning, Karin

    2016-10-01

    The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of nuclear-, hadron- and atomic physics experiments. The future PANDA experiment at FAIR will offer a broad physics programme with emphasis on different aspects of hadron physics. Understanding the strong interaction in the perturbative regime remains one of the greatest challenges in contemporary physics and hadrons provide several important keys. In these proceedings, PANDA will be presented along with some high-lights of the planned physics programme.

  18. Optimization and test of a 120mm LARP Nb3Sn quadrupole coil using magnetic mirror structure

    SciTech Connect

    Bossert, R.; Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Caspi, S.; Cheng, D.; Chlachidze, G.; Dietderich, D.; Felice, H.; Ferracin, P.; /LBL, Berkeley /Brookhaven /LBL, Berkeley /Fermilab /LBL, Berkeley /Brookhaven

    2011-09-01

    The US-LARP collaboration is developing a new generation of large-aperture high-field quadrupoles based on Nb{sub 3}Sn superconductor for the LHC upgrades. The development and implementation of this new technology involves the fabrication and testing of series of model magnets, coils and other components with various design and processing features. New 120-mm HQ coils made of Rutherford cable, one with an interlayer resistive core, and both with optimized reaction processes, were fabricated and tested using a quadrupole mirror structure under operating conditions similar to those in a real magnet. The coils were instrumented with voltage taps and strain gauges to study the mechanical and quench performance. Quench antenna and temperature gauges were installed in the mirror structure to measure the coil temperature and locate quench origins. This paper presents details of the coil design and fabrication procedures, coil assembly and pre-stress in the quadrupole mirror structure, and coil test results.

  19. Microscopic Study of Backbending Phenomena in 126-132Ce

    NASA Astrophysics Data System (ADS)

    Devi, Rani; Bhat, R. K.; Khosa, S. K.

    126-132Ce isotopes, which exhibit enhanced collective behavior and occurrence of first backbend around 10+, are studied in the Variation after Projection (VAP) and Cranked Hartree-Bogoliubov (CHB) frameworks. The pairing plus-quadrupole-quadrupole (PQQ) interaction is employed as an effective interaction. The yrast spectra, B(E2) transition probabilities and variation of moment of inertia versus cranking frequency are studied. Our results show that the backbending arises as a result of the sudden alignment of a pair of protons in the h11/2 subshell.

  20. A simple model for studying interacting networks

    NASA Astrophysics Data System (ADS)

    Liu, Wenjia; Jolad, Shivakumar; Schmittmann, Beate; Zia, R. K. P.

    2011-03-01

    Many specific physical networks (e.g., internet, power grid, interstates), have been characterized in considerable detail, but in isolation from each other. Yet, each of these networks supports the functions of the others, and so far, little is known about how their interactions affect their structure and functionality. To address this issue, we consider two coupled model networks. Each network is relatively simple, with a fixed set of nodes, but dynamically generated set of links which has a preferred degree, κ . In the stationary state, the degree distribution has exponential tails (far from κ), an attribute which we can explain. Next, we consider two such networks with different κ 's, reminiscent of two social groups, e.g., extroverts and introverts. Finally, we let these networks interact by establishing a controllable fraction of cross links. The resulting distribution of links, both within and across the two model networks, is investigated and discussed, along with some potential consequences for real networks. Supported in part by NSF-DMR-0705152 and 1005417.

  1. Intermolecular interaction studies of glyphosate with water

    NASA Astrophysics Data System (ADS)

    Manon, Priti; Juglan, K. C.; Kaur, Kirandeep; Sethi, Nidhi; Kaur, J. P.

    2017-07-01

    The density (ρ), viscosity (η) and ultrasonic velocity (U) of glyphosate with water have been measured on different ultrasonic frequency ranges from 1MHz, 2MHz, 3MHz & 5MHz by varying concentrations (0.05%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, & 0.40%) at 30°C. The specific gravity bottle, Ostwald's viscometer and quartz crystal interferometer were used to determine density (ρ), viscosity (η) and ultrasonic velocity (U). These three factors contribute in evaluating the other parameters as acoustic impedance (Z), adiabatic compressibility (β), relaxation time (τ), intermolecular free length (Lf), free volume (Vf), ultrasonic attenuation (α/f2), Rao's constant (R), Wada's constant (W) and relative strength (R). Solute-solvent interaction is confirmed by ultrasonic velocity and viscosity values, which increases with increase in concentration indicates stronger association between solute and solvent molecules. With rise in ultrasonic frequency the interaction between the solute and solvent particles decreases. The linear variations in Rao's constant and Wada's constant suggest the absence of complex formation.

  2. Finite Element Model of Training in the superconducting quadrupole magnet SQ02

    SciTech Connect

    Caspi, Shlomo; Ferracin, Paolo

    2007-11-01

    This paper describes the use of 3D finite element models to study training in superconducting magnets. The simulations are used to examine coil displacements when the electromagnetic forces are cycled, and compute the frictional energy released during conductor motion with the resulting temperature rise. A computed training curve is then presented and discussed. The results from the numerical computations are compared with test results of the Nb{sub 3}Sn racetrack quadrupole magnet SQ02.

  3. Focusing properties of a three-element quadrupole lens system and its stigmatic focusing behaviour

    NASA Astrophysics Data System (ADS)

    Zafar, Yu.

    The focusing properties of a three-element quadrupole lens system (triplet) have been studied in its general thick-lens form, and analytical expressions of corresponding matrix elements have been obtained. A graphical method has been utilized to determine the stigmatic focusing region of the triplet system generally, and in the special case of electrostatic triplet system installed in 'on-line SPIN-3 facility' in YASNAPP-2, JINR.

  4. Separation of closely eluting chloronaphthalene congeners by two-dimensional gas chromatography/quadrupole mass spectrometry: an advanced tool in the study and risk analysis of dioxin-like chloronaphthalenes.

    PubMed

    Hanari, Nobuyasu; Falandysz, Jerzy; Nakano, Takeshi; Petrick, Gert; Yamashita, Nobuyoshi

    2013-08-02

    Two capillary columns of different polarity were applied in a two-dimensional gas chromatography system coupled to a quadrupole mass spectrometric detection (GCxGC/qMS) in order to separate and identify all of the possible 22 isomers of tetra-, 14 of penta- and 10 of hexachloronaphthalene that may occur in selected industrial chemicals. The two-dimensional GCxGC separation was achieved using Rt-β DEXcst and DB-WAX phases, and data imaging was done by 2D and 3D mapping. This combination allows for the analysis of all tetra- to hexachloronaphthalene congeners in a single instrumental run without any pre-separation or fractionation of the analytes. The novel methodology described here can assist in the accurate determination and expression of dioxin-like toxicity of tetrachloronaphthalenes to octachloronaphthalene that are usually present as mixtures at least in abiotic materials such as technical chloronaphthalene formulations (e.g. Halowax mixtures), and wastes containing Halowaxes and other CN formulations.

  5. Enhancing the superconducting transition temperature of CeRh 1-x IrxIn5 due to the strong-coupling effects of antiferromagnetic spin fluctuations: an 115In nuclear quadrupole resonance study.

    PubMed

    Kawasaki, Shinji; Yashima, Mitsuharu; Mugino, Yoichi; Mukuda, Hidekazu; Kitaoka, Yoshio; Shishido, Hiroaki; Onuki, Yoshichika

    2006-04-14

    We report on systematic evolutions of antiferromagnetic (AFM) spin fluctuations and unconventional superconductivity (SC) in heavy-fermion (HF) compounds CeRh(1-x)Ir(x)In(5) via an (115)In nuclear-quadrupole-resonance experiment. The nuclear spin-lattice relaxation rate 1/T(1) has revealed the marked development of AFM spin fluctuations as approaching an AFM ordered state. Concomitantly, the superconducting transition temperature T(c) and the energy gap Delta0 increase drastically from T(c)= 0.4K and 2Delta0/k(B)T(c)=5 in CeIrIn(5) up to T(c) =1.2K and 2Delta0/k(B)T(c) =8.3 in CeRh(0.3)Ir(0.7)In5 , respectively. The present work suggests that the AFM spin fluctuations in close proximity to the AFM quantum critical point are indeed responsible for the strong-coupling unconventional SC in HF compounds.

  6. Quadrupole deformation of electron shells in the lattice dynamics of compressed rare-gas crystals

    NASA Astrophysics Data System (ADS)

    Troitskaya, E. P.; Chabanenko, Val. V.; Zhikharev, I. V.; Gorbenko, Ie. Ie.; Pilipenko, E. A.

    2012-06-01

    The lattice dynamics of rare-gas crystals has been constructed taking into account the deformation of electron shells of the atoms of the dipole and quadrupole types, depending on the displacement of the nuclei. The obtained equations of lattice vibrations have been investigated in the long-wavelength approximation. The role played by the three-body interaction and the deformation of the electron shells in the violation of the Cauchy relation has been discussed. The calculated Birch elastic moduli for Xe and deviations from the Cauchy relation are in good agreement with the available experimental data over a wide range of pressures.

  7. Charge Dependence and Electric Quadrupole Effects on Single-Nucleon Removal in Relativistic and Intermediate Energy Nuclear Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Single nucleon removal in relativistic and intermediate energy nucleus-nucleus collisions is studied using a generalization of Weizsacker-Williams theory that treats each electromagnetic multipole separately. Calculations are presented for electric dipole and quadrupole excitations and incorporate a realistic minimum impact parameter, Coulomb recoil corrections, and the uncertainties in the input photonuclear data. Discrepancies are discussed. The maximum quadrupole effect to be observed in future experiments is estimated and also an analysis of the charge dependence of the electromagnetic cross sections down to energies as low as 100 MeV/nucleon is made.

  8. Charge dependence and electric quadrupole effects on single-nucleon removal in relativistic and intermediate energy nuclear collisions

    NASA Technical Reports Server (NTRS)

    Norbury, J. W.; Townsend, L. W. (Principal Investigator)

    1990-01-01

    Single-nucleon removal in relativistic and intermediate energy nucleus-nucleus collisions is studied using a generalization of Weizsacker-Williams theory that treats each electromagnetic multipole separately. Calculations are presented for electric dipole and quadrupole excitations and incorporate a realistic minimum impact parameter, Coulomb recoil corrections, and the uncertainties in the input photonuclear data. Discrepancies are discussed. The maximum quadrupole effect to be observed in future experiments is estimated and also an analysis of the charge dependence of the electromagnetic cross sections down to energies as low as 100 MeV/nucleon is made.

  9. Molten uranium/Zircaloy interaction studies

    SciTech Connect

    Randklev, E.H.; Wolf, G.A.; Hinman, C.A.; Miller, G.E.; Quapp, W.J.

    1988-08-01

    A program has been initiated to determine the chemical interaction behavior, during a hypothetical loss-of-coolant (LOCA) in the N Reactor, between the zirconium alloy pressure tubing and the fuel (zirconium alloy-clad metallic uranium fuel) system components inside the tubing. The hypothetical accident consists of complete rupture of a primary coolant pipe, failure of the Emergency Core-Cooling System (ECCS), and operation of the Graphite and Shielding Cooling System (GSCS). Two series of scoping tests and two series of prototypic tests have been completed. The test results indicated that the most severe degradation (i.e., thinning) of the pressure tube wall occurred during elevated temperature tests in a nonoxidizing (argon) atmosphere at all outer element support locations (i.e., even when molten uranium alloy was not present in the attack zone). Segments of pressure tubes have been tested in argon for as long as 10 h at 1300{degree}C and have survived with at least 0.25 cm (0.10 in.) or more of wall thickness remaining in the regions of most severe attack (i.e., opposite the steel shoe/support locations). The attack at these support locations begins with the interdiffusion of iron from the steel shoes and the Zircaloy-2 pressure tube constituents. This interdiffusion results in information of a eutectic (liquid) at about 935{degree}C for the pure component system (85 wt % Zr/15 wt % Fe) and at a slightly lower temperature for this alloyed system. The results also indicate that beryllium from the Zircaloy-2/beryllium braze material used to attach the endcaps appears to increase the local attack by molten uranium in the lowermost region of the pressure tube ID profile. The effects of an oxidizing atmosphere (e.g., steam) on these interactions will be the subject of a series of follow-on tests in this project. 24 refs., 33 figs., 14 tabs.

  10. Fabrication and Test of LARP Technological Quadrupole Models of TQC Series

    SciTech Connect

    Bossert, Rodger C.; Ambrosio, Giorgio; Andreev, Nilolai; Barzi, Emanuela; Chlachidze, Guram; Feher, Sandor; Kashikhin, Vladimir S.; Kashikhin, Vadim V.; Lamm, Michael; Nobrega, Alfred; Novitski, Igor; Orris, Darryl; Tartaglia, Michael; Zlobin, Alexander V.; Caspi, Shlomo; Dietderich, Daniel R.; Ferracin, Paolo; Hafalia, A. R.; Sabbi, GianLuca; Ghosh, Arup; Wanderer, Peter

    2008-08-17

    In support of the development of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade, several two-layer technological quadrupole models of TQC series with 90 mm aperture and collar-based mechanical structure have been developed at Fermilab in collaboration with LBNL. This paper summarizes the results of fabrication and test of TQC02a, the second TQC model based on RRP Nb3Sn strand, and TQC02b, built with both MJR and RRP strand. The test results presented include magnet strain and quench performance during training, as well as quench studies of current ramp rate and temperature dependence from 1.9 K to 4.5 K.

  11. Role of the multipolar electrostatic interaction energy components in strong and weak cation-π interactions.

    PubMed

    Kadlubanski, Pawel; Calderón-Mojica, Katherine; Rodriguez, Weyshla A; Majumdar, D; Roszak, Szczepan; Leszczynski, Jerzy

    2013-08-22

    Density functional and Møller-Plesset second-order perturbation (MP2) calculations have been carried out on various model cation-π complexes formed through the interactions of Mg(2+), Ca(2+), and NH4(+) cations with benzene, p-methylphenol, and 3-methylindole. Partial hydration of the metal cations was also considered in these model studies to monitor the effect of hydration of cations in cation-π interactions. The binding energies of these complexes were computed from the fully optimized structures using coupled cluster calculations including triple excitations (CCSD(T)) and Gaussian-G4-MP2 (G4MP2) techniques. An analysis of the charge sharing between the donor (the π-systems) and the acceptors (the cations) together with the partitioning of total interaction energies revealed that the strong and weak cation-π interactions have similar electrostatic interaction properties. Further decomposition of such electrostatic terms into their multipolar components showed the importance of the charge-dipole, charge-quadrupole, and charge-octopole terms in shaping the electrostatic forces in such interactions. The computed vibrational spectra of the complexes were analyzed for the specific cation-π interaction modes and have been shown to contain the signature of higher order electrostatic interaction energy components (quadrupole and octopole) in such interactions.

  12. Theoretical investigation of flute modes in a magnetic quadrupole

    SciTech Connect

    Wu, H.S.

    1988-01-01

    This research developed theories and conducted numerical investigations of electrostatic flute modes in a plasma confined in a magnetic quadrupole. Chapter I presents the discussion of relevant background. Chapter II contains a brief discussion of the basic flute-mode operator L{sub 0} for intermediate- and low-frequency regimes. Chapter III develops a simple theory for a flute mode with frequency between the electron and ion bounce frequencies in the uniform density and temperature regions of a magnetic quadrupole. The frequency is predicted to be inversely proportional to the wave number. Chapter IV describes the kinetic approach. Chapter V contains the derivation of an eigenvalue equation for electrostatic waves with frequencies below the ion frequency in the private flux region of a magnetic quadrupole. Chapter VI develops a theory for electrostatic waves with frequency below the ion bounce frequency in the shared flux region of a magnetic quadrupole. Chapter VII contains the derivation of a dispersion equation for flute modes with frequencies between the electron and ion bounce frequencies in a plasma confined to a magnetic quadrupole. Chapter VIII presents a summary of the research described.

  13. Theoretical investigation of flute modes in a magnetic quadrupole

    SciTech Connect

    Wu, H.S.

    1988-01-01

    The objective of this research is to develop theories and conduct numerical investigations of electrostatic flute modes in a plasma confined in magnetic quadrupole. Chapter I presents the discussion of relevant background. Chapter II contains a brief discussion of the basic flute-mode operator L{sub 0} for intermediate- and low frequency regimes. Chapter III develops a simple theory for a flute mode with frequency between the electron and ion bounce frequencies in the uniform density and temperature regions of a magnetic quadrupole. Chapter IV describes the kinetic approach. Chapter V contains the derivation of an eigenvalue equation for electrostatic waves with frequencies below the ion frequency in the private flux region of a magnetic quadrupole. Chapter VI develops a theory for electrostatic waves with frequency below the ion bounce frequency in the shared flux region of a magnetic quadrupole. Chapter VII contains the derivation of a dispersion equation for flute modes with frequencies between the electron and ion ounce frequencies in a plasma confined to a magnetic quadrupole. Two intermediate-frequency modes are predicted.

  14. Studying Wind Energy/Bird Interactions: A Guidance Document

    SciTech Connect

    Anderson, R.; Morrison, M.; Sinclair, K.

    1999-12-01

    This guidance document is a product of the Avian Subcommittee of the National Wind Coordinating Committee (NWCC). The NWCC was formed to better understand and promote responsible, credible, and comparable avian/wind energy interaction studies. Bird mortality is a concern and wind power is a potential clean and green source of electricity, making study of wind energy/bird interactions essential. This document provides an overview for regulators and stakeholders concerned with wind energy/bird interactions, as well as a more technical discussion of the basic concepts and tools for studying such interactions.

  15. Study of volcano/ice interactions gains momentum

    USGS Publications Warehouse

    Chapman, Mary G.; Smellie, John L.; Gudmundsson, Magnus T.; Gulick, Virginia C.; Jakobsson, Sveinn P.; Skilling, Ian P.

    2001-01-01

    Observations of recent volcanic eruptions in Iceland and detailed studies of sub-glacially erupted deposits and the interaction of lava and pyroclastic flows with snow and ice have provided important new data that should lead to significant advances in the understanding of volcano/ice interaction on Earth and Mars. A conference on this subject, the first of its kind, recently brought together geologists, geophysicists, glaciologists, and planetary scientists studying various aspects of volcano-ice interaction.

  16. Fluorescence Studies of Protein Crystallization Interactions

    NASA Technical Reports Server (NTRS)

    Pusey, Marc L.; Smith, Lori; Forsythe, Elizabeth

    1999-01-01

    We are investigating protein-protein interactions in under- and over-saturated crystallization solution conditions using fluorescence methods. The use of fluorescence requires fluorescent derivatives where the probe does not markedly affect the crystal packing. A number of chicken egg white lysozyme (CEWL) derivatives have been prepared, with the probes covalently attached to one of two different sites on the protein molecule; the side chain carboxyl of ASP 101, within the active site cleft, and the N-terminal amine. The ASP 101 derivatives crystallize while the N-terminal amine derivatives do not. However, the N-terminal amine is part of the contact region between adjacent 43 helix chains, and blocking this site does would not interfere with formation of these structures in solution. Preliminary FRET data have been obtained at pH 4.6, 0.1M NaAc buffer, at 5 and 7% NaCl, 4 C, using the N-terminal bound pyrene acetic acid (PAA, Ex 340 nm, Em 376 nm) and ASP 101 bound Lucifer Yellow (LY, Ex 425 nm, Em 525 nm) probe combination. The corresponding Csat values are 0.471 and 0.362 mg/ml (approximately 3.3 and approximately 2.5 x 10 (exp 5) M respectively), and all experiments were carried out at approximately Csat or lower total protein concentration. The data at both salt concentrations show a consistent trend of decreasing fluorescence yield of the donor species (PAA) with increasing total protein concentration. This decrease is apparently more pronounced at 7% NaCl, consistent with the expected increased intermolecular interactions at higher salt concentrations (reflected in the lower solubility). The estimated average distance between protein molecules at 5 x 10 (exp 6) M is approximately 70 nm, well beyond the range where any FRET can be expected. The calculated RO, where 50% of the donor energy is transferred to the acceptor, for the PAA-CEWL * LY-CEWL system is 3.28 nm, based upon a PAA-CEWL quantum efficiency of 0.41.

  17. Fluorescence Studies of Protein Crystallization Interactions

    NASA Technical Reports Server (NTRS)

    Pusey, Marc L.; Smith, Lori; Forsythe, Elizabeth

    1999-01-01

    We are investigating protein-protein interactions in under- and over-saturated crystallization solution conditions using fluorescence methods. The use of fluorescence requires fluorescent derivatives where the probe does not markedly affect the crystal packing. A number of chicken egg white lysozyme (CEWL) derivatives have been prepared, with the probes covalently attached to one of two different sites on the protein molecule; the side chain carboxyl of ASP 101, within the active site cleft, and the N-terminal amine. The ASP 101 derivatives crystallize while the N-terminal amine derivatives do not. However, the N-terminal amine is part of the contact region between adjacent 43 helix chains, and blocking this site does would not interfere with formation of these structures in solution. Preliminary FRET data have been obtained at pH 4.6, 0.1M NaAc buffer, at 5 and 7% NaCl, 4 C, using the N-terminal bound pyrene acetic acid (PAA, Ex 340 nm, Em 376 nm) and ASP 101 bound Lucifer Yellow (LY, Ex 425 nm, Em 525 nm) probe combination. The corresponding Csat values are 0.471 and 0.362 mg/ml (approximately 3.3 and approximately 2.5 x 10 (exp 5) M respectively), and all experiments were carried out at approximately Csat or lower total protein concentration. The data at both salt concentrations show a consistent trend of decreasing fluorescence yield of the donor species (PAA) with increasing total protein concentration. This decrease is apparently more pronounced at 7% NaCl, consistent with the expected increased intermolecular interactions at higher salt concentrations (reflected in the lower solubility). The estimated average distance between protein molecules at 5 x 10 (exp 6) M is approximately 70 nm, well beyond the range where any FRET can be expected. The calculated RO, where 50% of the donor energy is transferred to the acceptor, for the PAA-CEWL * LY-CEWL system is 3.28 nm, based upon a PAA-CEWL quantum efficiency of 0.41.

  18. Tolerance analyses of a quadrupole magnet for advanced photon source upgrade

    SciTech Connect

    Liu, J. Jaski, M. Borland, M.; Jain, A.

    2016-07-27

    Given physics requirements, the mechanical fabrication and assembly tolerances for storage ring magnets can be calculated using analytical methods [1, 2]. However, this method is not easy for complicated magnet designs [1]. In this paper, a novel method is proposed to determine fabrication and assembly tolerances consistent with physics requirements, through a combination of magnetic and mechanical tolerance analyses. In this study, finite element analysis using OPERA is conducted to estimate the effect of fabrication and assembly errors on the magnetic field of a quadrupole magnet and to determine the allowable tolerances to achieve the specified magnetic performances. Based on the study, allowable fabrication and assembly tolerances for the quadrupole assembly are specified for the mechanical design of the quadrupole magnet. Next, to achieve the required assembly level tolerances, mechanical tolerance stackup analyses using a 3D tolerance analysis package are carried out to determine the part and subassembly level fabrication tolerances. This method can be used to determine the tolerances for design of other individual magnets and of magnet strings.

  19. Study of interaction of ceruloplasmin with serprocidins.

    PubMed

    Sokolov, A V; Ageeva, K V; Kostevich, V A; Berlov, M N; Runova, O L; Zakharova, E T; Vasilyev, V B

    2010-11-01

    This paper describes formation of complexes of ceruloplasmin (CP) with such proteins of the serprocidin family as azurocidin (CAP37), neutrophilic elastase (NE), cathepsin G (CG), and proteinase 3 (PR3). We present evidence that serprocidins form complexes with CP at a molar ratio 1 : 1. Phenylmethylsulfonyl fluoride, a serine protease inhibitor, did not prevent the interaction of serprocidins with CP in the course of SDS-free disc electrophoresis. CP affected the activities of NE, CG, and PR3 as a competitive inhibitor with K(i) ~ 1 μM. Inhibitory effect of CP depended on ionic strength of the solution and was negligible at NaCl concentrations above 300 mM. In the mode of competitive inhibitors serprocidins suppressed oxidase activity of CP towards p-phenylenediamine. CAP37 displayed the strongest inhibitory effect (K(i) ~ 20 nM). Upon adding various serprocidins to human, rat, rabbit, dolphin, dog, horse, and mouse plasma only CAP37 would form a complex with CP. Synthetic peptide RKARPRQFPRRR (5-13, 61-63 CAP37) displaced CAP37 from its complex with CP. Adding CAP37 to the triple complex formed by CP, lactoferrin, and myeloperoxidase resulted in displacement of the latter from the complex. The dissociation constant of CAP37 with immobilized CP was 13 nM. Therefore, among serprocidins CAP37 can be regarded as the specific partner of CP.

  20. Determinants of Internet Use for Interactive Learning: An Exploratory Study

    ERIC Educational Resources Information Center

    Castaño, Jonatan; Duart, Josep M.; Sancho-Vinuesa, Teresa

    2015-01-01

    The use of the Internet in higher education teaching can facilitate the interactive learning process and thus improve educational outcomes. The aim of the study presented here is to explore which variables are linked to higher intensity of Internet-based interactive educational practices. The study is based on data obtained from an online survey…

  1. Interactions among Online Learners: A Quantitative Interdisciplinary Study

    ERIC Educational Resources Information Center

    Jain, Pawan; Jain, Sachin; Jain, Smita

    2011-01-01

    This study concerns the design and development of online instruction and specifically targets interaction and communication between online learners. Facilitating appropriate and meaningful interactions in designing instruction is a major goal for anyone developing a course, especially an online class. The data for this study came from the online…

  2. Fluorimetric study on the interaction between Norfloxacin and Proflavine hemisulphate.

    PubMed

    More, Vishalkumar R; Anbhule, Prashant V; Lee, Sang H; Patil, Shivajirao R; Kolekar, Govind B

    2011-07-01

    The interaction between Norfloxacin (NF) and Proflavine hemisulphate (PF) was investigated by spectroscopic tools like UV-VIS absorption and Fluorescence spectroscopy. It was proved that fluorescence quenching of NF by PF is due to the formation of NF-PF complex which was supported by UV-VIS absorption study. The study of thermodynamic parameters suggested that the key interacting forces are hydrogen bond and van der Waal's interactions and the binding interaction was spontaneous. The distance r between NF and PF was obtained according to the Förster's theory of non-radiative energy transfer. The fluorescence quenching mechanism was applied to estimate PF directly from pharmaceutical samples.

  3. Cryogen free superconducting splittable quadrupole magnet for linear accelerators

    SciTech Connect

    Kashikhin, V.S.; Andreev, N.; Kerby, J.; Orlov, Y.; Solyak, N.; Tartaglia, M.; Velev, G.; /Fermilab

    2011-09-01

    A new superconducting quadrupole magnet for linear accelerators was fabricated at Fermilab. The magnet is designed to work inside a cryomodule in the space between SCRF cavities. SCRF cavities must be installed inside a very clean room adding issues to the magnet design, and fabrication. The designed magnet has a splittable along the vertical plane configuration and could be installed outside of the clean room around the beam pipe previously connected to neighboring cavities. For more convenient assembly and replacement a 'superferric' magnet configuration with four racetrack type coils was chosen. The magnet does not have a helium vessel and is conductively cooled from the cryomodule LHe supply pipe and a helium gas return pipe. The quadrupole generates 36 T integrated magnetic field gradient, has 600 mm effective length, and the peak gradient is 54 T/m. In this paper the quadrupole magnetic, mechanical, and thermal designs are presented, along with the magnet fabrication overview and first test results.

  4. Dark energy reflections in the redshift-space quadrupole.

    PubMed

    Yamamoto, Kazuhiro; Bassett, Bruce A; Nishioka, Hiroaki

    2005-02-11

    We show that the redshift-space quadrupole will be a powerful tool for constraining dark energy even if the baryon oscillations are missing from the monopole power spectrum and bias is scale and time dependent. We calculate the accuracy with which next-generation galaxy surveys such as KAOS will measure the quadrupole power spectrum, which gives the leading anisotropies in the power spectrum in redshift space due to linear velocity, and the so-called "Finger of God" and Alcock-Paczynski effects. Combining the monopole and quadrupole power spectra, in the complete absence of baryon oscillations (Omegab=0), leads to a roughly 500% improvement in constraints on dark energy compared with those from the monopole spectrum alone.

  5. Variable-field permanent magnet quadrupole for the SSC

    SciTech Connect

    Barlow, D.B.; Kraus, R.H. Jr.; Martinez, R.P.; Meyer, R.E.

    1993-10-01

    A set of compact variable-field permanent-magnet quadrupoles have been designed, fabricated, and tested for use In the SSC linac matching section. The quadrupoles have 24 mm-diameter apertures and 40 mm-long poles. The hybrid (permanent-magnet and iron) design, uses a fixed core of magnet material (NdFeB) and iron (C-1006) surrounded by a rotating ring of the same magnet material and iron. The quadrupole gradient-length product can be smoothly varied from a minimum of 0.7 T up to a maximum, of 4.3 T by a 90{degrees} rotation of the outer ring of iron and magnet material.

  6. Modal response of 4-rod type radio frequency quadrupole linac

    SciTech Connect

    Chatterjee, Avik; Mahapatra, Abhijit; Mondal, Manas; Chakrabarti, Alok

    2009-10-15

    This paper deals with the analysis and experimental study of natural frequencies of vibration of a 4-rod type radio frequency quadrupole (RFQ) linear accelerator. The eigenvalue analysis of the structure has been done both analytically (multispan beam concept) as well as using blocked Lanczos eigenvalue finite element solver with an ability to extract the rigid body modes. This has been done in the mechanical design phase to find the level of agreement between the output of simplified analytical analysis results and the output of a commercial finite element method (FEM) solver, since a full scale RFQ structure is too complex to handle analytically. Experimental validation of the analysis results has been done on the physical 1.7 m RFQ at the installation site. The experimental data obtained were later analyzed and found to be in close agreement with the predicted frequencies in the lower frequency ranges. It gets more and more deviated in the higher frequency ranges. Also some frequencies were observed during experimentation, which were not found in the finite element analysis results. The source of those frequencies are to be further investigated as it may play a predominant role in the design high quality factor beam line cavities for higher operational efficiency.

  7. "Fast Excitation" CID in Quadrupole Ion Trap Mass Spectrometer

    SciTech Connect

    Murrell, J.; Despeyroux, D.; Lammert, Stephen {Steve} A; Stephenson Jr, James {Jim} L; Goeringer, Doug

    2003-01-01

    Collision-induced dissociation (CID) in a quadrupole ion trap mass spectrometer is usually performed by applying a small amplitude excitation voltage at the same secular frequency as the ion of interest. Here we disclose studies examining the use of large amplitude voltage excitations (applied for short periods of time) to cause fragmentation of the ions of interest. This process has been examined using leucine enkephalin as the model compound and the motion of the ions within the ion trap simulated using ITSIM. The resulting fragmentation information obtained is identical with that observed by conventional resonance excitation CID. ''Fast excitation'' CID deposits (as determined by the intensity ratio of the a{sub 4}/b{sub 4} ion of leucine enkephalin) approximately the same amount of internal energy into an ion as conventional resonance excitation CID where the excitation signal is applied for much longer periods of time. The major difference between the two excitation techniques is the higher rate of excitation (gain in kinetic energy) between successive collisions with helium atoms with ''fast excitation'' CID as opposed to the conventional resonance excitation CID. With conventional resonance excitation CID ions fragment while the excitation voltage is still being applied whereas for ''fast excitation'' CID a higher proportion of the ions fragment in the ion cooling time following the excitation pulse. The fragmentation of the (M + 17H){sup 17+} of horse heart myoglobin is also shown to illustrate the application of ''fast excitation'' CID to proteins.

  8. Modal response of 4-rod type radio frequency quadrupole linac.

    PubMed

    Chatterjee, Avik; Mahapatra, Abhijit; Mondal, Manas; Chakrabarti, Alok

    2009-10-01

    This paper deals with the analysis and experimental study of natural frequencies of vibration of a 4-rod type radio frequency quadrupole (RFQ) linear accelerator. The eigenvalue analysis of the structure has been done both analytically (multispan beam concept) as well as using blocked Lanczos eigenvalue finite element solver with an ability to extract the rigid body modes. This has been done in the mechanical design phase to find the level of agreement between the output of simplified analytical analysis results and the output of a commercial finite element method (FEM) solver, since a full scale RFQ structure is too complex to handle analytically. Experimental validation of the analysis results has been done on the physical 1.7 m RFQ at the installation site. The experimental data obtained were later analyzed and found to be in close agreement with the predicted frequencies in the lower frequency ranges. It gets more and more deviated in the higher frequency ranges. Also some frequencies were observed during experimentation, which were not found in the finite element analysis results. The source of those frequencies are to be further investigated as it may play a predominant role in the design high quality factor beam line cavities for higher operational efficiency.

  9. Newly developed apparatus for calibration of quadrupole mass spectrometer

    NASA Astrophysics Data System (ADS)

    Meng, Dong; Yongjun, Cheng; Detian, Li; Wenjun, Sun; Lan, Zhao; Meiru, Guo; Yongjun, Wang; Huzhong, Zhang; Yanwu, Li; Gang, Li

    2017-01-01

    In this paper, a new calibration apparatus has been developed for calibrating quadrupole mass spectrometer (QMS) from 10-8 Pa to 10-2 Pa for He, N2 and Ar. Based on the apparatus, two calibration methods are introduced to generate standard pressure P i ‧ (or P i ″) of lower than 10-2 Pa, which are named as ‘the SRG measurement method’ and ‘the CDG measurement method’. The SRG measurement method can generate a standard pressure range from 10-8 Pa to 10-5 Pa, and the CDG measurement method can generate a standard pressure range from 10-5 Pa to 10-2 Pa. A molecular flow condition is determined and a QMS is calibrated by the two methods using single gas and mixture gas. The gas flow through the small tube and orifice realizes molecular flow at an upstream pressure of less than 70 Pa. The sensitivities calibration results with the two methods agree well, and the difference is less than 3%. The sensitivity calibrated with single gas is different from that calibrated with mixture gas. Obtained results are roughly consistent with those of previous studies.

  10. On the formation of the South Pacific quadrupole mode

    NASA Astrophysics Data System (ADS)

    Zheng, Jian; Wang, Faming

    2016-08-01

    The formation process of the South Pacific (SP) quadrupole (SPQ) mode was investigated in this study based on observations and reanalysis data. The SPQ is the dominant mode of the sea surface temperature (SST)-surface wind covariability in the SP after removing the ENSO-related signals. The positive phase of the SPQ is characterized by a warm SST anomaly (SSTA) west of the South American coast, a cool SSTA in its southwest, a positive SSTA southeast of New Zealand, and a negative SSTA off the southeast coast of Australia, overlain by cyclonic wind anomalies. The anomalous cyclonic winds weaken the mean southeast trade winds in the southeast SP and the westerlies in the high latitudes of the SP, increasing the SSTAs at the two positive poles through decreased evaporation and latent heat flux (LHF) loss. The southeast wind anomalies advect dry and cold air to the negative pole in the central SP, which reduces the SSTA there by increasing the LHF loss. Off the southeast coast of Australia, the southwest wind anomalies induce equatorward Ekman currents and advect cold water. The resulting oceanic horizontal advection is the main contributor to the negative SSTAs there. In addition to the above processes, cloud cover change can enhance the initial SSTAs in the southeast SP by affecting shortwave radiation. The decay of the SPQ is mainly due to LHF changes.

  11. Effect of a serrated trailing edge on sound radiation from nearby quadrupoles.

    PubMed

    Karimi, Mahmoud; Croaker, Paul; Kinns, Roger; Kessissoglou, Nicole

    2017-05-01

    A periodic boundary element technique is implemented to study the noise reduction capability of a plate with a serrated trailing edge under quadrupole excitation. It is assumed for this purpose that the quadrupole source tensor is independent of the trailing edge configuration and that the effect of the trailing edge shape is to modify sound radiation from prescribed boundary layer sources. The flat plate is modelled as a continuous structure with a finite repetition of small spanwise segments. The matrix equation formulated by the periodic boundary element method for this 3D acoustic scattering problem is represented as a block Toeplitz matrix. The discrete Fourier transform is employed in an iterative algorithm to solve the block Toeplitz system. The noise reduction mechanism for a serrated trailing edge in the near field is investigated by comparing contour plots obtained from each component of the quadrupole for unserrated and serrated trailing edge plate models. The noise reduction due to the serrated trailing edge is also examined as a function of the source location.

  12. Electric and magnetic long-range interactions between two Erbium atoms

    NASA Astrophysics Data System (ADS)

    Dulieu, Olivier; Lepers, Maxence; Aymar, Mireille; Luc, Eliane; Wyart, Jean-Francois

    2011-05-01

    Lanthanides have recently attracted a lot of interest in the field of laser-cooling and trapping. Their high magnetic dipole moment - seven Bohr magnetons for Erbium - opens new prospects for the precise control of their mutual interactions. As they are also characterized by a high orbital angular momentum, they also interact through their permanent electric quadrupole moments. We have studied the combined effects of the magnetic-dipole and electric-quadrupole interaction as functions of the distance R between two atoms of Erbium. Although they scale as R-3 and R-5 respectively, we have shown that the two types of interaction can compete with each other in a wide range of interatomic distances. This is due to the weakness of magnetic forces compared to electric ones. For example, we observe long-range wells, which could drastically influence the collisional properties of the atoms. Our calculations can be generalized to other lanthanides, like Dysprosium.

  13. Interactions of Isophorone Derivatives with DNA: Spectroscopic Studies

    PubMed Central

    Deiana, Marco; Matczyszyn, Katarzyna; Massin, Julien; Olesiak-Banska, Joanna; Andraud, Chantal; Samoc, Marek

    2015-01-01

    Interactions of three new isophorone derivatives, Isoa Isob and Isoc with salmon testes DNA have been investigated using UV-Vis, fluorescence and circular dichroism spectroscopic methods. All the studied compounds interact with DNA through intercalative binding mode. The stoichiometry of the isophorone/DNA adducts was found to be 1:1. The fluorescence quenching data revealed a binding interaction with the base pairs of DNA. The CD data indicate that all the investigated isophorones induce DNA modifications. PMID:26069963

  14. Origin of low-energy quadrupole collectivity in vibrational nuclei.

    PubMed

    Walz, C; Fujita, H; Krugmann, A; von Neumann-Cosel, P; Pietralla, N; Ponomarev, V Yu; Scheikh-Obeid, A; Wambach, J

    2011-02-11

    The coupling of the giant quadrupole resonance to valence-space configurations is shown to be the origin of the formation of low-lying quadrupole-collective structures in vibrational nuclei with symmetric and mixed-symmetric character with respect to the proton-neutron degree of freedom. For the first time experimental evidence for this picture is obtained from electron- and proton scattering experiments on the nucleus ^{92}Zr that are sensitive to the relative phase of valence-space amplitudes by quantum interference.

  15. Observation of Excited Quadrupole-Bound States in Cold Anions

    NASA Astrophysics Data System (ADS)

    Zhu, Guo-Zhu; Liu, Yuan; Wang, Lai-Sheng

    2017-07-01

    We report the first observation of an excited quadrupole-bound state (QBS) in an anion. High-resolution photoelectron imaging of cryogenically cooled 4-cyanophenoxide (4 CP- ) anions yields an electron detachment threshold of 24 927 cm-1 . The photodetachment spectrum reveals a resonant transition 20 cm-1 below the detachment threshold, which is attributed to an excited QBS of 4 CP- because neutral 4CP has a large quadrupole moment with a negligible dipole moment. The QBS is confirmed by observation of seventeen above-threshold resonances due to autodetachment from vibrational levels of the QBS.

  16. Conceptual design of a quadrupole magnet for eRHIC

    SciTech Connect

    Witte, H.; Berg, J. S.

    2015-05-03

    eRHIC is a proposed upgrade to the existing Relativistic Heavy Ion Collider (RHIC) hadron facility at Brookhaven National Laboratory, which would allow collisions of up to 21 GeV polarized electrons with a variety of species from the existing RHIC accelerator. eRHIC employs an Energy Recovery Linac (ERL) and an FFAG lattice for the arcs. The arcs require open-midplane quadrupole magnets of up to 30 T/m gradient of good field quality. In this paper we explore initial quadrupole magnet design concepts based on permanent magnetic material which allow to modify the gradient during operation.

  17. Simulation of nuclear quadrupole resonance for sensor probe optimization.

    PubMed

    Shinohara, Junichiro; Sato-Akaba, Hideo; Itozaki, Hideo

    2012-01-01

    A simulation method to estimate the detection efficiency of nuclear quadrupole resonance (NQR) was proposed for optimizing a sensing probe operating at radio frequencies (RFs). It first calculates the transmitted magnetic field from the probe coil to the target sample. The nuclei make quadrupole resonance by it. We considered this nonlinear reaction to estimate NQR emission by the nuclei. Then the received NQR signal intensity from the sample at the probe coil. We calculated the efficiency by testing two different probe types (solenoid and gradiometer) and by changing the relative positions of the probe and sample. The simulation results were in good agreement with the experimental results.

  18. High and ulta-high gradient quadrupole magnets

    SciTech Connect

    Brunk, W.O.; Walz, D.R.

    1985-05-01

    Small bore conventional dc quadrupoles with apertures from 1 to 2.578cm were designed and prototypes built and measured. New fabrication techniques including the use of wire electric discharge milling (EDM) to economically generate the pole tip contours and aperture tolerances are described. Magnetic measurement data from a prototype of a 1cm aperture quadrupole with possible use in future e/sup +//e/sup -/ super colliders are presented. At a current of 400A, the lens achieved a gradient of 2.475 T/cm, and had an efficiency of 76.6%.

  19. Phase and Radial Motion in a Transverse Electric Quadrupole - Manufacturing

    SciTech Connect

    Billen, James; Crandall, Ken; Young, Lloyd

    2010-06-25

    ParmteqM comprises a group of codes (PARMTEQ, RFQUICK, CURLI, PARI, PARMTEQM, READVG and VANES) that are used to design high-performance radio-frequency quadrupole (RFQ) linacs. PARMTEQ is an acronym for "Phase and Radial Motion in a Transverse Electric Quadrupole". These codes are necessary to design the RFQ vane profile and analyze the beam performance including the effects of higher order multipole field components and image charges. Multi-particle simulations are supported in Version 3. PARMTEQM, VANES and READVG specifically provide manufacturing support to generate CNC machining instructions for the fabrication of vane profiles.

  20. Study of soliton interactions in sodium vapor

    NASA Astrophysics Data System (ADS)

    Dolfi, D. W.; Hahn, E. L.

    1980-04-01

    Collision properties of optical solitons are studied experimentally using the technique of self-induced transparency. Numerical plane-wave simulations of collisions using parameters for the input pulses and the atomic system appropriate to the actual experimental situation are presented and compared to matching analytic solutions derived previously by other workers. Experimental studies of overtaking collisions in sodium vapor are presented for the first time and found to be in qualitative agreement with numerical results at intermediate optical absorption. At higher absorption, dynamic transverse effects cause a rapid attenuation of the pulses which prevents the observation of complete collisions. Attempts to compensate for losses by focusing the input beam are described.

  1. Theoretical Studies of Atom Surface Interactions

    DTIC Science & Technology

    1981-02-01

    on Electron Stimulated Desorption 19. KEY WORDS (Continue on reverse side if necessary and Identify by block nualber) Theoretical Study Kinetic Theorm...roughly giveti by S.. by averaging thle homionuclea. diatomiic bond lengths.’ If thie molecule remains undiss6eiated, Ems c2/S , () then e2/S, is the

  2. A Study of Teacher-Learner Interactions: A Continuum Between Monologic and Dialogic Interactions.

    PubMed

    Kathard, Harsha; Pillay, Daisy; Pillay, Mershen

    2015-07-01

    Teachers and learners must be able to shift flexibly along the continuum of monologic and dialogic interactional repertoires to advance learning. This article describes how teachers and learners interacted during whole-class instruction along the continuum between monologic and dialogic interaction in primary school classrooms in Western Cape, South Africa. A video-observation method was used to analyze teacher-learner interactions (TLIs) across 15 lessons in intermediate-phase classrooms. TLIs were analyzed in relation to indicators such as authority, questions, feedback, explanation, metalevel connection, and collaboration. The transcriptions of TLIs were described using quantitative and qualitative techniques. The study found that teachers sustained dominant monologic interactions by asserting their authority, asking mainly closed-ended questions, and providing confirming/correcting feedback that constrained the interaction. Learners had limited opportunities for explanations or collaboration. Across most lessons, there were episodic shifts from monologic TLIs to transitional TLIs. These transitions were achieved by using mainly open-ended questions and feedback to expand the interaction. Dialogic TLIs were not evident. Monologic TLIs were dominant, closing down opportunities for communication. Although transitional TLIs were evident, they were episodic and showed the potential for opening interaction opportunities. The absence of dialogic TLIs suggested that collaborative engagement opportunities were unavailable. The opportunity for intervention to increase dialogic TLIs is discussed.

  3. Ocean dynamics studies. [of current-wave interactions

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Both the theoretical and experimental investigations into current-wave interactions are discussed. The following three problems were studied: (1) the dispersive relation of a random gravity-capillary wave field; (2) the changes of the statistical properties of surface waves under the influence of currents; and (3) the interaction of capillary-gravity with the nonuniform currents. Wave current interaction was measured and the feasibility of using such measurements for remote sensing of surface currents was considered. A laser probe was developed to measure the surface statistics, and the possibility of using current-wave interaction as a means of current measurement was demonstrated.

  4. Structural study of surfactant-dependent interaction with protein

    SciTech Connect

    Mehan, Sumit; Aswal, Vinod K.; Kohlbrecher, Joachim

    2015-06-24

    Small-angle neutron scattering (SANS) has been used to study the complex structure of anionic BSA protein with three different (cationic DTAB, anionic SDS and non-ionic C12E10) surfactants. These systems form very different surfactant-dependent complexes. We show that the structure of protein-surfactant complex is initiated by the site-specific electrostatic interaction between the components, followed by the hydrophobic interaction at high surfactant concentrations. It is also found that hydrophobic interaction is preferred over the electrostatic interaction in deciding the resultant structure of protein-surfactant complexes.

  5. Study of molecular interactions with 13C DNP-NMR

    NASA Astrophysics Data System (ADS)

    Lerche, Mathilde H.; Meier, Sebastian; Jensen, Pernille R.; Baumann, Herbert; Petersen, Bent O.; Karlsson, Magnus; Duus, Jens Ø.; Ardenkjær-Larsen, Jan H.

    2010-03-01

    NMR spectroscopy is an established, versatile technique for the detection of molecular interactions, even when these interactions are weak. Signal enhancement by several orders of magnitude through dynamic nuclear polarization alleviates several practical limitations of NMR-based interaction studies. This enhanced non-equilibrium polarization contributes sensitivity for the detection of molecular interactions in a single NMR transient. We show that direct 13C NMR ligand binding studies at natural isotopic abundance of 13C gets feasible in this way. Resultant screens are easy to interpret and can be performed at 13C concentrations below μM. In addition to such ligand-detected studies of molecular interaction, ligand binding can be assessed and quantified with enzymatic assays that employ hyperpolarized substrates at varying enzyme inhibitor concentrations. The physical labeling of nuclear spins by hyperpolarization thus provides the opportunity to devise fast novel in vitro experiments with low material requirement and without the need for synthetic modifications of target or ligands.

  6. SAXS studies of ion-nucleic acid interactions.

    PubMed

    Pollack, Lois

    2011-01-01

    Positively charged ions, atoms, or molecules compensate the high negative charge of the nucleic acid backbone. Their presence is critical to the biological function of DNA and RNA. This review focuses on experimental studies probing (a) interactions between small ions and nucleic acids and (b) ion-mediated interactions between nucleic acid duplexes. Experimental results on these simple model systems can be compared with specific theoretical models to validate their predictions. Small angle X-ray scattering (SAXS) provides unique insight into these interactions. Anomalous SAXS reports the spatial correlations of condensed (e.g., locally concentrated) counterions to individual DNA or RNA duplexes. SAXS very effectively reports interactions between nucleic acid helices, which range from strongly repulsive to strongly attractive depending on the ionic species present. The sign and strength of interparticle interactions are easily deduced from dramatic changes in the scattering profiles of interacting duplexes.

  7. The129I hyperfine interaction in fatty acids studied by Mössbauer spectroscopy

    NASA Astrophysics Data System (ADS)

    Burda, K.; Strzałka, K.; Stanek, J.

    1993-12-01

    Oleic acid substituted by iodine and saponified by Ca2+ cations has been studied by129I Mössbauer spectroscopy. The quadrupole coupling constants and isomer shifts, determined from the γ-resonance spectra recorded at 4.2 K, have been described by 5p and 5s orbital populations of iodine. It was also found that saponification of the fatty acid has no significant influence on the measured iodine bonds. However, the increased order of fatty acids in soap form is reflected by narrowing of the resonant linewidth due to the reduction of the electric field gradient distribution.

  8. Teacher Adoption of Interactive Whiteboards: A Case Study

    ERIC Educational Resources Information Center

    Rosevear, Joseph

    2009-01-01

    This case study investigated the process of adopting and integrating interactive whiteboards into the daily practice of teachers and compared the findings to relevant theoretical models. Participants were drawn from a small international school in Damascus, Syria, where interactive whiteboards were introduced for the first time. The findings…

  9. Using Facebook Data to Analyze Learner Interaction during Study Abroad

    ERIC Educational Resources Information Center

    Back, Michele

    2013-01-01

    Although study abroad is viewed as an ideal environment for interaction in the target language, research in this area has relied mostly upon self-reported data, which pose challenges regarding recall bias and participant commitment. This article shows how Facebook data can be used to analyze naturally occurring learner interactions during study…

  10. Studies defining interactions between hypertension and air pollutants

    SciTech Connect

    Drew, R T; Costa, D L; Haber, S; Iwai, J

    1980-01-01

    An animal model of hypertension was developed by breeding two lines of rats. The model was used to investigate interactions between commonly encountered air pollutants and the development of hypertension. This paper summarizes studies of the interaction of sulfur dioxide and ozone with the models. (ACR)

  11. Seating Position and Interaction in Triads: A Field Study

    ERIC Educational Resources Information Center

    Silverstein, C. Harris; Stang, David J.

    1976-01-01

    Relationships between seating position, length of acquaintance between subjects, observer bias toward the experimental outcome, and interaction rates are examined in a field study. Subjects with greatest visual centrality spoke most often. Length of acquaintance between subjects was unrelated to interaction rates. (Author/DEP)

  12. Using Facebook Data to Analyze Learner Interaction during Study Abroad

    ERIC Educational Resources Information Center

    Back, Michele

    2013-01-01

    Although study abroad is viewed as an ideal environment for interaction in the target language, research in this area has relied mostly upon self-reported data, which pose challenges regarding recall bias and participant commitment. This article shows how Facebook data can be used to analyze naturally occurring learner interactions during study…

  13. A study of the flow field surrounding interacting line fires

    Treesearch

    Trevor Maynard; Marko Princevac; David R. Weise

    2016-01-01

    The interaction of converging fires often leads to significant changes in fire behavior, including increased flame length, angle, and intensity. In this paper, the fluid mechanics of two adjacent line fires are studied both theoretically and experimentally. A simple potential flow model is used to explain the tilting of interacting flames towards each other, which...

  14. Experimental study of exciton-surface plasmon interactions

    NASA Astrophysics Data System (ADS)

    Brillante, A.; Pockrand, I.

    Plasmon surface polariton (PSP) spectroscopy has been applied to dye monolayer assemblies on silver films to study exciton-surface plasmon interactions. Depending on the orientation of the dye transition dipole moment the interaction leads to characteristic changes in the dispersion curve of PSP's in agreement with theoretical results.

  15. A Usability Study of Interactive Web-Based Modules

    ERIC Educational Resources Information Center

    Girard, Tulay; Pinar, Musa

    2011-01-01

    This research advances the understanding of the usability of marketing case study modules in the area of interactive web-based technologies through the assignment of seven interactive case modules in a Principles of Marketing course. The case modules were provided for marketing students by the publisher, McGraw Hill Irwin, of the…

  16. The Assessment of Selectivity in Different Quadrupole-Orbitrap Mass Spectrometry Acquisition Modes

    NASA Astrophysics Data System (ADS)

    Berendsen, Bjorn J. A.; Wegh, Robin S.; Meijer, Thijs; Nielen, Michel W. F.

    2015-02-01

    Selectivity of the confirmation of identity in liquid chromatography (tandem) mass spectrometry using Q-Orbitrap instrumentation was assessed using different acquisition modes based on a representative experimental data set constructed from 108 samples, including six different matrix extracts and containing over 100 analytes each. Single stage full scan, all ion fragmentation, and product ion scanning were applied. By generating reconstructed ion chromatograms using unit mass window in targeted MS2, selected reaction monitoring (SRM), regularly applied using triple-quadrupole instruments, was mimicked. This facilitated the comparison of single stage full scan, all ion fragmentation, (mimicked) SRM, and product ion scanning applying a mass window down to 1 ppm. Single factor Analysis of Variance was carried out on the variance (s2) of the mass error to determine which factors and interactions are significant parameters with respect to selectivity. We conclude that selectivity is related to the target compound (mainly the mass defect), the matrix, sample clean-up, concentration, and mass resolution. Selectivity of the different instrumental configurations was quantified by counting the number of interfering peaks observed in the chromatograms. We conclude that precursor ion selection significantly contributes to selectivity: monitoring of a single product ion at high mass accuracy with a 1 Da precursor ion window proved to be equally selective or better to monitoring two transition products in mimicked SRM. In contrast, monitoring a single fragment in all ion fragmentation mode results in significantly lower selectivity versus mimicked SRM. After a thorough inter-laboratory evaluation study, the results of this study can be used for a critical reassessment of the current identification points system and contribute to the next generation of evidence-based and robust performance criteria in residue analysis and sports doping.

  17. Computational Study of Combustor-Turbine Interactions

    NASA Technical Reports Server (NTRS)

    Miki, Kenji; Liou, Meng-Sing

    2017-01-01

    The Open National Combustion Code (OpenNCC) is applied to the simulation of a realisticcombustor configuration [Energy Efficient Engine (E(exp. 3))] in order to investigate the unsteady flow fields inside the combustor and around the first stage stator of a high pressure turbine (HPT). We consider one-twelfth (24 degrees) of the full annular E(exp. 3) combustor with three different geometries of the combustor exit: one without the vane, and two others with the vane set at different relative positions in relation to the fuel nozzle (clocking). Although it is common to take the exit flow profiles obtained by separately simulating the combustor and then feed it as the inflow profile when modeling the HPT, our studies show that the unsteady flow fields are influenced by the presence of the vane as well as clocking. More importantly, the characteristics (e.g., distribution and strength) of the high temperature spots (i.e., hot-streaks) appearing on the vane significantly alters. This indicates the importance of simultaneously modeling both the combustor and the HPT to understand the mechanics of the unsteady formulation of hot-streaks.

  18. Etintidine-theophylline interaction study in humans.

    PubMed

    Huang, S M; Weintraub, H S; Marriott, T B; Marinan, B; Abels, R; Leese, P T

    1987-01-01

    Etintidine HCl is a potent H2-blocker. The effect of clinical doses of etintidine on the disposition of theophylline was investigated in 10 male volunteers. This was a double-blind, two-way crossover study. Each subject received etintidine (400 mg) or placebo twice a day with meals for 4 days on two occasions (separated by 4 days). On each occasion, the subjects were fasted overnight on Day 3 and were given an oral dose of theophylline elixir (5 mg/kg) 30 min following the administration of the morning dose of etintidine or placebo on Day 4. Blood samples were collected prior to and up to 24 h following the administration of theophylline. Plasma theophylline levels were analysed by HPLC. Theophylline was rapidly absorbed following oral administration of the theophylline elixir to both the placebo and etintidine treatment groups. Comparison of the pharmacokinetic parameters of theophylline between the etintidine and the placebo groups indicates that while etintidine did not significantly (p greater than 0.05) affect the apparent Cmax (11.1 vs 10.0 micrograms ml-1) and Tmax (1.7 vs 1.4 h) values of theophylline, etintidine significantly reduced the oral clearance (0.0200 vs 0.0564 l kg-1 h-1, p = 0.000006) and prolonged the elimination half-life (16.8 vs 6.0 h) of theophylline. The data indicate that etintidine, like cimetidine, extended the elimination of theophylline in humans.

  19. Quadrupole-driven non-Fermi-liquid and magnetic-field-induced heavy fermion states in a non-Kramers doublet system

    NASA Astrophysics Data System (ADS)

    Onimaru, T.; Izawa, K.; Matsumoto, K. T.; Yoshida, T.; Machida, Y.; Ikeura, T.; Wakiya, K.; Umeo, K.; Kittaka, S.; Araki, K.; Sakakibara, T.; Takabatake, T.

    2016-08-01

    Orbital degrees of freedom in condensed matter could play important roles in forming a variety of exotic electronic states by interacting with conduction electrons. In 4 f -electron systems, because of strong intra-atomic spin-orbit coupling, an orbitally degenerate state inherently carries quadrupolar degrees of freedom. The present work has focused on a purely quadrupole-active system PrIr2Zn20 showing superconductivity in the presence of an antiferroquadrupole order at TQ=0.11 K. We observed non-Fermi-liquid (NFL) behaviors emerging in the electrical resistivity ρ and the 4 f contribution to the specific heat, C4 f, in the paramagnetic state at T > TQ. Moreover, in magnetic fields B ≤6 T, all data sets of ρ (T ) and C4 f(T ) are well scaled with characteristic temperatures T0's. This observation of the NFL state in the nonmagnetic quadrupole-active system has an origin intrinsically different from that observed in the vicinity of the conventional quantum critical point. It implies possible formation of a quadrupole Kondo lattice resulting from hybridization between the quadrupoles and the conduction electrons with an energy scale of kBT0 . At T ≤0.13 K, ρ (T ) and C4 f(T ) exhibit anomalies as B approaches 5 T. This is the manifestation of a field-induced crossover toward a Fermi-liquid ground state in the quadrupole Kondo lattice.

  20. Ab-initio calculations of electric field gradient in Ru compounds and their implication on the nuclear quadrupole moments of ^{99}Ru and ^{101}Ru

    NASA Astrophysics Data System (ADS)

    Mishra, S. N.

    2017-08-01

    The nuclear quadrupole moments, Q, for the ground and first excited states in ^{99}Ru and ground state of ^{101}Ru have been determined by comparing the experimentally observed quadrupole interaction frequencies ν _Q with calculated electric field gradient (EFG) for a large number of Ru-based compounds. The ab-initio calculations of EFG were performed using the all-electron augmented plane wave + local orbital (APW + lo) method of the density functional theory (DFT). From the slope of the linear correlation between theoretically calculated EFGs and experimentally observed ν _Q, we obtain the quadrupole moment for the (5/2^+) ground state in ^{99}Ru and ^{101}Ru as 0.0734(17) b and 0.431(14) b respectively, showing excellent agreement with the values reported in literature. For 3/2^+, the quadrupole moment of the first excited state in ^{99}Ru is obtained as +0.203(3) b, which is considerably lower than the commonly accepted literature value of +0.231(12) b. The results presented in this paper would be useful for the precise determination of quadrupole moment of high spin states in other Ru isotopes and is likely to stimulate further shell model calculations for an improved understanding of nuclear shape in these nuclei.