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Sample records for hybrid permanent quadrupoles

  1. Hybrid high gradient permanent magnet quadrupole

    Science.gov (United States)

    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.

  2. Tunable high-gradient permanent magnet quadrupoles

    CERN Document Server

    Shepherd, B J A; Marks, N; Collomb, N A; Stokes, D G; Modena, M; Struik, M; Bartalesi, A

    2014-01-01

    A novel type of highly tunable permanent magnet (PM) based quadrupole has been designed by the ZEPTO collaboration. A prototype of the design (ZEPTO-Q1), intended to match the specification for the CLIC Drive Beam Decelerator, was built and magnetically measured at Daresbury Laboratory and CERN. The prototype utilises two pairs of PMs which move in opposite directions along a single vertical axis to produce a quadrupole gradient variable between 15 and 60 T/m. The prototype meets CLIC's challenging specification in terms of the strength and tunability of the magnet.

  3. Permanent magnet quadrupoles for the CLIC Drive Beam decelerator

    CERN Document Server

    Shepherd, Ben; Collomb, Norbert

    2012-01-01

    STFC in collaboration with CERN has developed a new type of adjustable permanent magnet based quadrupole for the CLIC Drive Beam Decelerator. It uses vertical movement of the permanent magnets to achieve an integrated gradient range of 3.6-14.6T, which will allow it to be used for the first 60% of the decelerator line. Construction of a prototype of this magnet has begun; following this, it will be measured magnetically at CERN and Daresbury Laboratory.

  4. Performance of an Adjustable Strength Permanent Magnet Quadrupole

    CERN Document Server

    Gottschalk, Stephen C; Kangas, Kenneth; Spencer, Cherrill M; Volk, James T

    2005-01-01

    An adjustable strength permanent magnet quadrupole suitable for use in Next Linear Collider has been built and tested. The pole length is 42cm, aperture diameter 13mm, peak pole tip strength 1.03Tesla and peak integrated gradient * length (GL) is 68.7 Tesla. This paper describes measurements of strength, magnetic centerline and field quality made using an air bearing rotating coil system. The magnetic centerline stability during -20% strength adjustment proposed for beam based alignment was < 0.2 microns. Strength hysteresis was negligible. Thermal expansion of quadrupole and measurement parts caused a repeatable and easily compensated change in the vertical magnetic centerline. Calibration procedures as well as centerline measurements made over a wider tuning range of 100% to 20% in strength useful for a wide range of applications will be described. The impact of eddy currents in the steel poles on the magnetic field during strength adjustments will be reported.

  5. Stability considerations of permanent magnet quadrupoles for CESR phase-III upgrade

    Directory of Open Access Journals (Sweden)

    W. Lou

    1998-06-01

    Full Text Available The Cornell electron storage ring (CESR phase-III upgrade plan includes very strong permanent magnet quadrupoles in front of the cryostat for the superconducting quadrupoles and physically as close as possible to the interaction point. Together with the superconducting quadrupoles, they provide tighter vertical focusing at the interaction point. The quadrupoles are built with neodymium iron boron (NdFeB material and operate inside the 15 kG solenoid field. Requirements on the field quality and stability of these quadrupoles are discussed and test results are presented.

  6. Characterization of the ELIMED prototype permanent magnet quadrupole system

    Science.gov (United States)

    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.

  7. Characterization and tuning of ultrahigh gradient permanent magnet quadrupoles

    Directory of Open Access Journals (Sweden)

    S. Becker

    2009-10-01

    Full Text Available The application of quadrupole devices with high field gradients and small apertures requires precise control over higher order multipole field components. We present a new scheme for performance control and tuning, which allows the illumination of most of the quadrupole device aperture because of the reduction of higher order field components. Consequently, the size of the aperture can be minimized to match the beam size achieving field gradients of up to 500  T m^{-1} at good imaging quality. The characterization method based on a Hall probe measurement and a Fourier analysis was confirmed using the high quality electron beam at the Mainz Microtron MAMI.

  8. Design and Manufacture of a Hybrid Final Focus Quadrupole Model for CLIC

    CERN Document Server

    Modena, Michele; Vorozhtsov, Alexey

    2012-01-01

    A tunable hybrid quadrupole magnet design has been proposed for the final focus in the Compact Linear Collider (CLIC) that is currently under study. The proposed design is a combination of an iron dominated electromagnetic quadrupole with a bore diameter of 8.25 mm with permanent magnet blocks placed between the poles made of soft magnetic CoFe alloy "Permendur". The possibility of using Sm2Co17 and Nd2Fe14B as material for the permanent magnet blocks has been investigated. It is shown that a very high field gradient of 530 T/m (Sm2Co17) and 590 T/m (Nd2Fe14B) can be achieved.

  9. Magnetic Measurements of Permanent and Fast-Pulsed Quadrupoles for the CERN LINAC4 Project

    CERN Document Server

    Golluccio, G; Buzio, M; Dunkel, O; Giloteaux, D; Lombardi, A; Mateo, F; Ramberger, S

    2010-01-01

    Linac4 is currently under construction at CERN to improve intensity and reliability for the whole accelerator chain. This machine will include about 120 permanent quadrupoles housed in the Drift Tube tanks, as well as about 80 electromagnetic quadrupoles. This paper describes the magnetic measurements carried out at CERN on the first batch of quadrupoles, including several prototypes from different manufacturers, as well as those done on several spare Linac 2 magnets reused in Linac4's 3 MeV test stand. We first describe a prototype test bench based on technology developed for the LHC and able to carry out high-precision harmonic measurements in both continuously-rotating and stepping-coil mode. Next we present the first results obtained in terms of field strength, harmonics quality and effects of fast eddy current transients. Finally, we discuss the expected impact of these findings on the operation of the machine.

  10. H-mode accelerating structures with permanent-magnet quadrupole beam focusing

    Science.gov (United States)

    Kurennoy, S. S.; Rybarcyk, L. J.; O'Hara, J. F.; Olivas, E. R.; Wangler, T. P.

    2012-09-01

    We have developed high-efficiency normal-conducting rf accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of interdigital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3D modeling—electromagnetic computations, multiparticle beam-dynamics simulations with high currents, and thermal-stress analysis—for an IH-PMQ accelerator tank are presented. The accelerating-field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. Examples of cross-bar H-mode structures with PMQ focusing for higher beam velocities are also presented. H-PMQ accelerating structures following a short radio-frequency quadrupole accelerator can be used both in the front end of ion linacs or in stand-alone applications.

  11. Characterization of the ELIMED Permanent Magnets Quadrupole system prototype with laser-driven proton beams

    Science.gov (United States)

    Schillaci, F.; Pommarel, L.; Romano, F.; Cuttone, G.; Costa, M.; Giove, D.; Maggiore, M.; Russo, A. D.; Scuderi, V.; Malka, V.; Vauzour, B.; Flacco, A.; Cirrone, G. A. P.

    2016-07-01

    Laser-based accelerators are gaining interest in recent years as an alternative to conventional machines [1]. In the actual ion acceleration scheme, energy and angular spread of the laser-driven beams are the main limiting factors for beam applications and different solutions for dedicated beam-transport lines have been proposed [2,3]. In this context a system of Permanent Magnet Quadrupoles (PMQs) has been realized [2] by INFN-LNS (Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare) researchers, in collaboration with SIGMAPHI company in France, to be used as a collection and pre-selection system for laser driven proton beams. This system is meant to be a prototype to a more performing one [3] to be installed at ELI-Beamlines for the collection of ions. The final system is designed for protons and carbons up to 60 MeV/u. In order to validate the design and the performances of this large bore, compact, high gradient magnetic system prototype an experimental campaign have been carried out, in collaboration with the group of the SAPHIR experimental facility at LOA (Laboratoire d'Optique Appliquée) in Paris using a 200 TW Ti:Sapphire laser system. During this campaign a deep study of the quadrupole system optics has been performed, comparing the results with the simulation codes used to determine the setup of the PMQ system and to track protons with realistic TNSA-like divergence and spectrum. Experimental and simulation results are good agreement, demonstrating the possibility to have a good control on the magnet optics. The procedure used during the experimental campaign and the most relevant results are reported here.

  12. An improved permanent magnet quadrupole design with larger good field region for high intensity proton linacs

    Energy Technology Data Exchange (ETDEWEB)

    Mathew, Jose V., E-mail: josev.mathew@gmail.com; Rao, S.V.L.S.; Krishnagopal, S.; Singh, P.

    2013-11-01

    The Low Energy High Intensity Proton Accelerator (LEHIPA), being developed at the Bhabha Atomic Research Centre (BARC) will produce a 20 MeV, 30 mA, continuous wave (CW) proton beam. At these low velocities, space-charge forces dominate, and could lead to larger beam sizes and beam halos. Hence in the design of the focusing lattice of the LEHIPA drift tube linac (DTL) using permanent magnet quadrupoles (PMQs), a larger good field region is preferred. Here we study, using the two dimensional (2D) and three dimensional (3D) simulation codes PANDIRA and RADIA, four different types of cylindrical PMQ designs: 16-segment trapezoidal Halbach configuration, bullet-nosed geometry and 8- and 16-segment rectangular geometries. The trapezoidal Halbach geometry is used in a variety of accelerators since it provides very high field gradients in small bores, while the bullet-nosed geometry, which is a combination of the trapezoidal and rectangular designs, is used in some DTLs. This study shows that a larger good field region is possible in the 16-segment rectangular design as compared to the Halbach and bullet-nosed designs, making it more attractive for high-intensity proton linacs. An improvement in good-field region by ∼16% over the Halbach design is obtained in the optimized 16-segment rectangular design, although the field gradient is lower by ∼20%. Tolerance studies show that the rectangular segment PMQ design is substantially less sensitive to the easy axis orientation errors and hence will be a better choice for DTLs. -- Highlights: • An improved permanent magnet quadrupole (PMQ) design with larger good field region is proposed. • We investigate four PMQ designs, including the widely used Halbach and bullet nosed designs. • Analytical calculations are backed by 2D as well as 3D numerical solvers, PANDIRA and RADIA. • The optimized 16 segment rectangular PMQ design is identified to exhibit the largest good field region. • The effect of easy axis orientation

  13. A modified Rogowski coil for measurements of hybrid permanent magnets

    Energy Technology Data Exchange (ETDEWEB)

    Bertsche, K.

    1996-08-01

    For large permanent magnets, as proposed for the Fermilab Recycler Ring, it may be important to quickly verify that the magnet`s strength is correct. This may be important, for example, if a magnet is suspected of having changed due to some sort of accident. The field strength of a pure dipole can be readily measured with a Hall probe, but for indexed dipoles and for quadrupoles a Hall probe will not give very accurate results without precise positioning. We have investigated a different approach, the use of a modified Rogowski coil to measure the magnetic potential of each pole. As long as magnet geometry is fixed and known, measurement of the magnetic potential at each pole gives a good measurement of field strength even for magnets with large quadrupole components. The construction and use of such a coil and the precision of measurements made with it will be discussed. 4 refs., 5 figs.

  14. An improved permanent magnet quadrupole design with larger good field region for high intensity proton linacs

    Science.gov (United States)

    Mathew, Jose V.; Rao, S. V. L. S.; Krishnagopal, S.; Singh, P.

    2013-11-01

    The Low Energy High Intensity Proton Accelerator (LEHIPA), being developed at the Bhabha Atomic Research Centre (BARC) will produce a 20 MeV, 30 mA, continuous wave (CW) proton beam. At these low velocities, space-charge forces dominate, and could lead to larger beam sizes and beam halos. Hence in the design of the focusing lattice of the LEHIPA drift tube linac (DTL) using permanent magnet quadrupoles (PMQs), a larger good field region is preferred. Here we study, using the two dimensional (2D) and three dimensional (3D) simulation codes PANDIRA and RADIA, four different types of cylindrical PMQ designs: 16-segment trapezoidal Halbach configuration, bullet-nosed geometry and 8- and 16-segment rectangular geometries. The trapezoidal Halbach geometry is used in a variety of accelerators since it provides very high field gradients in small bores, while the bullet-nosed geometry, which is a combination of the trapezoidal and rectangular designs, is used in some DTLs. This study shows that a larger good field region is possible in the 16-segment rectangular design as compared to the Halbach and bullet-nosed designs, making it more attractive for high-intensity proton linacs. An improvement in good-field region by ˜16% over the Halbach design is obtained in the optimized 16-segment rectangular design, although the field gradient is lower by ˜20%. Tolerance studies show that the rectangular segment PMQ design is substantially less sensitive to the easy axis orientation errors and hence will be a better choice for DTLs.

  15. An adjustable focusing system for a 2 MeV H- ion beam line based on permanent magnet quadrupoles

    CERN Document Server

    Nirkko, M; Ereditato, A; Kreslo, I; Scampoli, P; Weber, M

    2012-01-01

    A compact adjustable focusing system for a 2 MeV H- RFQ Linac is designed, constructed and tested based on four permanent magnet quadrupoles (PMQ). A PMQ model is realised using finite element simulations, providing an integrated field gradient of 2.35 T with a maximal field gradient of 57 T/m. A prototype is constructed and the magnetic field is measured, demonstrating good agreement with the simulation. Particle track simulations provide initial values for the quadrupole positions. Accordingly, four PMQs are constructed and assembled on the beam line, their positions are then tuned to obtain a minimal beam spot size of (1.2 x 2.2) mm^2 on target. This paper describes an adjustable PMQ beam line for an external ion beam. The novel compact design based on commercially available NdFeB magnets allows high flexibility for ion beam applications.

  16. Low-field permanent magnet quadrupoles in a new relativistic-klystron two-beam accelerator design

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S.; Sessler, A. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    Permanent magnets play a central role in the new relativistic klystron two-beam-accelerator design. The two key goals of this new design, low cost and the suppression of beam break-up instability are both intimately tied to the permanent magnet quadrupole focusing system. A recently completed systems study by a joint LBL-LLNL team concludes that a power source for a 1 TeV center-of-mass Next Linear Collider based on the new TBA design can be as low as $1 billion, and the efficiency (wall plug to rf) is estimated to be 36%. End-to-end simulations of longitudinal and transverse beam dynamics show that the drive beam is stable over the entire TBA unit.

  17. Analysis and Design of Hybrid Excitation Permanent Magnet Synchronous Generators

    Institute of Scientific and Technical Information of China (English)

    JIN Wan-bing; ZHANG Dong; AN Zhong-liang; TAN Ren-yuan

    2006-01-01

    On the basis of a conventional permanent magnet (PM) synchronous generator's construction,a novel kind of Hybrid Excitation Permanent Magnet Synchronous Generator (HEPMSG) is introduced by inserting exciting winding in the stator or rotor.Firstly,the construction of HEPMSG is improved with the addition of PM excitation on the ferromagnetic pole,and its working principle and design method are studied in detail.Then,an appropriate exciting current control system is presented considering the characteristics of HEPMSG.Finally,a prototype is made,and test results confirm the analysis and design.

  18. Permanent magnet quadrupole for the 1-ST tank of LINAC-4

    CERN Document Server

    Skachkov, Vl; Sergeeva, O; Lombardi, A; Sargsyan, E; Cornuet, D; Venturini , W; Skachkov , V

    2006-01-01

    A rare-earth (REPM) ∅ 60 mm diameter, 45 mm long quadrupole for the LINAC-4 focusing channel with an integrated gradient of 2.3 T is described. Thin side washers are used for tuning the quad into specified gradient integral with ±0.5 % accuracy. The single washer contribution calculations are discussed. A method for limiting to 30 μ m the magnetic axis offset in the REPM quad is discussed to exclude its compensation by the outer diameter machining before inserting into the drift tube. Nonlinearity of the field is less than 1 % in the reference range of 75 % of beam aperture at the central cross- section near the quad axis . The angular quadrupole arrangement in the drift tube will be provided by machining the main groove on the quad surface in the median plane with 1 mrad accuracy. Calculations of the longitudinal gradient distribution between two...

  19. A Practical Permanent Magnetic Motor Drive for Hybrid Motorcycle

    Institute of Scientific and Technical Information of China (English)

    崔巍; 江建中; 邵定国; 杨斌

    2003-01-01

    A novel embedded-type permanent magnetic motor for hybrid motorcycle, which employs asymmetric design of eccentric air-gap, is proposed in the paper. This special design of air-gap well conforms to the mono-directional operation characteristic of motorcycle and effectively suppresses the distortion of air-gap magnetic field caused by armature reaction. Hence the torque ripple is reduced. A drive system consisting of the newly-designed Nd-Fe-B permanent magnet synchronous motor and parallel-MOSFET threephase inverter for hybrid motorcycle propulsion is established. Wide-range speed operation is realized through a simple and novel control strategy. Computer simulation is described and experimental results given to verify the practicality of the proposed motor design and control strategy.

  20. Photovoltaic-wind hybrid system for permanent magnet DC motor

    Science.gov (United States)

    Nasir, M. N. M.; Lada, M. Y.; Baharom, M. F.; Jaafar, H. I.; Ramani, A. N.; Sulaima, M. F.

    2015-05-01

    Hybrid system of Photovoltaic (PV) - Wind turbine (WT) generation has more advantages and reliable compared to PV or wind turbine system alone. The aim of this paper is to model and design hybrid system of PV-WT supplying 100W permanent-magnet dc motor. To achieve the objective, both of PV and WT are connected to converter in order to get the same source of DC supply. Then both sources were combined and straightly connected to 100W permanent magnet dc motor. All the works in this paper is only applied in circuit simulator by using Matlab Simulink. The output produced from each converter is expected to be suit to the motor specification. The output produced from each renewable energy system is as expected to be high as it can support the motor if one of them is breakdown

  1. In Situ Characterisation of Permanent Magnetic Quadrupoles for focussing proton beams

    CERN Document Server

    Melone, J J; McCanny, T; Burris-Mog, T; Schramm, U; Grötschel, R; Akhmadaliev, S; Hanf, D; Spohr, K M; Bussmann, M; Cowan, T; Wiggins, S M; Mitchell, M R

    2011-01-01

    High intensity laser driven proton beams are at present receiving much attention. The reasons for this are many but high on the list is the potential to produce compact accelerators. However two of the limitations of this technology is that unlike conventional nuclear RF accelerators lasers produce diverging beams with an exponential energy distribution. A number of different approaches have been attempted to monochromise these beams but it has become obvious that magnetic spectrometer technology developed over many years by nuclear physicists to transport and focus proton beams could play an important role for this purpose. This paper deals with the design and characterisation of a magnetic quadrupole system which will attempt to focus and transport laser-accelerated proton beams.

  2. Modeling of Hybrid Permanent Magnetic-Gas Bearings

    DEFF Research Database (Denmark)

    Morosi, Stefano; Santos, Ilmar

    2009-01-01

    Modern turbomachinery applications require nowadays ever-growing rotational speeds and high degree of reliability. It then becomes natural to focus the attention of the research to contact-free bearings elements. The present alternatives focus on gas lubricated journal bearings or magnetic bearings....... In the present paper both the technologies are combined with the aim of developing a new kind of hybrid permanent magnetic - gas bearing. This new kind of machine is intended to exploit the benefits of the two technologies while minimizing their drawbacks. The poor start-up and low speed operation performance...... of the gas bearing is balanced by the properties of the passive magnetic one. At high speeds the dynamic characteristics of the gas bearing are improved by offsetting the stator ring of the permanent magnetic bearing. Furthermore this design shows a kind of redundancy, which offers soft failure properties...

  3. Performance Characteristics of a New Hybrid Triple Quadrupole Time-of-Flight Tandem Mass Spectrometer

    Science.gov (United States)

    Andrews, Genna L.; Simons, Brigitte L.; Young, J. Bryce; Hawkridge, Adam M.; Muddiman, David C.

    2011-01-01

    The TripleTOF 5600 System, a hybrid triple quadrupole time-of-flight mass spectrometer, was evaluated to explore the key figures of merit in generating peptide and protein identifications which included spectral acquisition rates, data quality, proteome coverage, and biological depth. Employing a Saccharomyces cerevisiae tryptic digest, careful consideration of several performance features demonstrated that the speed of the TripleTOF contributed most to the resultant data. The TripleTOF system was operated with 8, 20, and 50 MS/MS events in an effort to compare to other MS technologies and to demonstrate the abilities of the instrument platform. PMID:21619048

  4. Comparison of conventional and novel quadrupole drift tube magnets inspired by Klaus Halbach

    Energy Technology Data Exchange (ETDEWEB)

    Feinberg, B. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    Quadrupole drift tube magnets for a heavy-ion linac provide a demanding application of magnet technology. A comparison is made of three different solutions to the problem of providing an adjustable high-field-strength quadrupole magnet in a small volume. A conventional tape-wound electromagnet quadrupole magnet (conventional) is compared with an adjustable permanent-magnet/iron quadrupole magnet (hybrid) and a laced permanent-magnet/iron/electromagnet (laced). Data is presented from magnets constructed for the SuperHILAC heavy-ion linear accelerator, and conclusions are drawn for various applications.

  5. Characterization of laser-driven single and double electron bunches with a permanent magnet quadrupole triplet and pepper-pot mask

    Science.gov (United States)

    Manahan, G. G.; Brunetti, E.; Aniculaesei, C.; Anania, M. P.; Cipiccia, S.; Islam, M. R.; Grant, D. W.; Subiel, A.; Shanks, R. P.; Issac, R. C.; Welsh, G. H.; Wiggins, S. M.; Jaroszynski, D. A.

    2014-10-01

    Electron beams from laser-plasma wakefield accelerators have low transverse emittance, comparable to those from conventional radio frequency accelerators, which highlights their potential for applications, many of which will require the use of quadrupole magnets for optimal electron beam transport. We report on characterizing electron bunches where double bunches are observed under certain conditions. In particular, we present pepper-pot measurements of the transverse emittance of 120-200 MeV laser wakefield electron bunches after propagation through a triplet of permanent quadrupole magnets. It is shown that the normalized emittance at source can be as low as 1 π mm mrad (resolution limited), growing by about five times after propagation through the quadrupoles due to beam energy spread. The inherent energy-dependence of the magnets also enables detection of double electron bunches that could otherwise remain unresolved, providing insight into the self-injection of multiple bunches. The combination of quadrupoles and pepper-pot, in addition, acts as a diagnostic for the alignment of the magnetic triplet.

  6. Analysis and design of permanent magnet biased magnetic bearing based on hybrid factor

    Directory of Open Access Journals (Sweden)

    Jinji Sun

    2016-03-01

    Full Text Available In this article, hybrid factor is proposed for hybrid magnetic bearing. The hybrid factor is defined as the ratio of the force produced by the permanent magnet and the forces produced by the permanent magnet and current in hybrid magnetic bearing. It is deduced from a certain radial hybrid magnetic bearing using its important parameters such as the current stiffness and displacement stiffness at first and then the dynamic model of magnetically suspended rotor system is established. The relationship between structural parameters and control system parameters is analyzed based on the hybrid factor. Some influencing factors of hybrid factor in hybrid magnetic bearing, such as the size of the permanent magnet, length of air gap, and area of the stator poles, are analyzed in this article. It can be concluded that larger hybrid factor can be caused by the smaller power loss according to the definition of hybrid factor mentioned above. Meanwhile, the hybrid factor has a maximum value, which is related to control system parameters such as proportional factor expect for structural parameters. Finally, the design steps of parameters of hybrid magnetic bearing can be concluded.

  7. Effect of the repulsive force in the HTSC-permanent magnet hybrid bearing system

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, S., E-mail: ohashi@ipcku.kansai-u.ac.j [Kansai University, 3-3-35, Yamate-cho, Suita, Osaka 564-8680 (Japan); Kobayashi, S. [Kansai University, 3-3-35, Yamate-cho, Suita, Osaka 564-8680 (Japan)

    2009-10-15

    Magnetic levitation using the pinning force of the YBaCuO high-T{sub c} bulk superconductor (HTSC) materials has an advantage to achieve stable levitation without control. To increase levitation force, the HTSC-permanent magnet hybrid magnetic bearing system is introduced. A circular shaped three phase Nd-Fe-B permanent magnet is installed on the rotor, and HTSC bulk superconductor is set on the stator. The additional permanent magnet is installed under the HTSC. Repulsive force of the permanent magnet is used for levitation, and pinning force between the HTSC and permanent magnet is used for guidance force of the bearing. In this system, relationship between permanent magnet and the HTSC is important. When repulsive force of the permanent magnet is large, pinning force of superconductor is used to keep the rotor position. As a result, stability for the lateral direction is decreased with hybrid system. For levitation force, effect of the hybrid system is not observed with column HTSC. Compared with the ring HTSC results, the following thing is considered. Because there is no space that flux of one permanent magnet acts on the other one with the column HTSC configuration, interaction between two permanent magnets becomes small.

  8. Effect of the repulsive force in the HTSC-permanent magnet hybrid bearing system

    Science.gov (United States)

    Ohashi, S.; Kobayashi, S.

    2009-10-01

    Magnetic levitation using the pinning force of the YBaCuO high- Tc bulk superconductor (HTSC) materials has an advantage to achieve stable levitation without control. To increase levitation force, the HTSC-permanent magnet hybrid magnetic bearing system is introduced. A circular shaped three phase Nd-Fe-B permanent magnet is installed on the rotor, and HTSC bulk superconductor is set on the stator. The additional permanent magnet is installed under the HTSC. Repulsive force of the permanent magnet is used for levitation, and pinning force between the HTSC and permanent magnet is used for guidance force of the bearing. In this system, relationship between permanent magnet and the HTSC is important. When repulsive force of the permanent magnet is large, pinning force of superconductor is used to keep the rotor position. As a result, stability for the lateral direction is decreased with hybrid system. For levitation force, effect of the hybrid system is not observed with column HTSC. Compared with the ring HTSC results, the following thing is considered. Because there is no space that flux of one permanent magnet acts on the other one with the column HTSC configuration, interaction between two permanent magnets becomes small.

  9. Demonstration of single-shot picosecond time-resolved MeV electron imaging using a compact permanent magnet quadrupole based lens

    CERN Document Server

    Cesar, D; Musumeci, P; Sun, Y; Harrison, J; Frigola, P; O'Shea, F H; To, H; Alesini, D; Li, R K

    2016-01-01

    We present the results of an experiment where a short focal length (~ 1.3 cm) permanent magnet electron lens is used to image micron-size features of a metal sample in a single shot, using an ultra- high brightness ps-long 4 MeV electron beam from a radiofrequency photoinjector. Magnifcation ratios in excess of 30x were obtained using a triplet of compact, small gap (3.5 mm), Halbach-style permanent magnet quadrupoles with nearly 600 T/m field gradients. These results pave the way to- wards single shot time-resolved electron microscopy and open new opportunities in the applications of high brightness electron beams.

  10. Rotational characteristics in the resonance state of the HTSC-permanent magnet hybrid magnetic bearing

    Energy Technology Data Exchange (ETDEWEB)

    Morii, Y.; Sukedai, M. [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Ohashi, S., E-mail: ohashi@kansai-u.ac.jp [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan)

    2011-11-15

    The hybrid magnetic bearing has been developed. In the hybrid system, effect of the pinning force becomes smaller. Influence of the vibration and the gradient angle in the resonance state is large. The resonance frequency becomes small in the hybrid bearing system. The hybrid magnetic bearing using permanent magnets and the high-Tc bulk superconductor (HTSC) has been developed. Repulsive force of the permanent magnet is introduced to increase the load weight of the magnetic bearing. Effect of the hybrid system has been shown. In this paper, influence of the hybrid system on the dynamic characteristics of the rotor is studied. The rotational characteristics in the mechanical resonance state are studied, and the equivalent magnetic spring coefficient is estimated from the experimental results of the load weight. The resonance frequency is measured by the rotation experiments. The rotor achieves stable levitation even in the resonance state. In the hybrid system, effect of the pinning force becomes smaller than that of the lateral force generated by the repulsive force between the two permanent magnets at the smaller air gap. Thus influence of the lateral vibration and the gradient angle in the resonance state becomes larger at a smaller air gap. The equivalent magnetic spring coefficient becomes also small, and the resonance frequency becomes small in the hybrid bearing system.

  11. Improvement of the levitation stability of the HTSC-permanent magnet hybrid bearing by using the new arrangement of the permanent magnet

    Science.gov (United States)

    Sukedaia, M.; Emoto, K.; Sugiyama, R.; Ohashi, S.

    The hybrid magnetic bearing using permanent magnets and the high temperature superconductor (HTSC) has been developed. Repulsive force of the permanent magnet is introduced to increase the load weight of the magnetic bearing. Effect of the hybrid system has been shown. Although the previous configuration improves the load weight of the rotor, levitation and guidance stability has been decreased because of the repulsive force of the permanent magnet. Three-dimensional numerical analysis of the system has been undertaken to reduce lateral force which decreases lateral stability of the rotor. From the results, effective arrangement of the hybrid system is given. Increment of the load weight is confirmed. Influence of the hybrid system on the pinning force between the HTSC and the permanent magnet is shown to be smaller than previous one.

  12. Study of the hybrid controller electronics for the nano-stabilization of mechanical vibrations of CLIC quadrupoles

    CERN Document Server

    Fernandez Carmona, P; Collette, C; Esposito, M; Guinchard, M; Janssens, S; Kuzmin, A; Moron Ballester, R

    2011-01-01

    In order to achieve the required levels of luminosity in the CLIC linear collider, mechanical stabilization of quadrupoles to the nanometre level is required. The paper describes a design of hybrid electronics combining an analogue controller and digital communication with the main machine controller. The choice of local analogue control ensures the required low latency while still keeping sufficiently low noise level. Furthermore, it reduces the power consumption, rack space and cost. Sensitivity to radiation single events upsets is reduced compared to a digital controller. The digital part is required for fine tuning and real time monitoring via digitization of critical parameters.

  13. HYBRID LAYER THICKNESS IN PRIMARY AND PERMANENT TEETH – A COMPARISON BETWEEN TOTAL ETCH ADHESIVES

    Directory of Open Access Journals (Sweden)

    Natalia Gateva

    2012-05-01

    Full Text Available Purpose: The aim this study is to compare the hybrid layer thickness and its micromorphological characteristics in samples from primary and permanent teeth following application of total etch adhesives.Materials and methods: On intact specimens of 20 primary and 10 permanent teeth was created flat dentin surfaces. The patterns were divided in 6 groups. Two different total etch adhesive systems were used – one tree steps (OptiBond, Kerr and one two steps (Exite, VivaDent. In groups 3, 4, 5 and 6 recommended etching time was used - 15 s, in groups 1 and 2 the etching time was reduced to 7 s. After applying the adhesive, resin composite build-ups were constructed. Thus restored samples are stored in saline solution for 24 hours at temperature 37 C. Then they are subjected to thermal stress in temperature between 5 C to 55 C for 1,500 cycles and to masticatory stress – 150,000 cycles with force 100 N in intervals of 0.4 s. After that the teeth are cut through the middle in medio-distal direction with a diamond disc. SEM observation was done to investigate the thickness of the hybrid layer and the presence of microgaps. Statistical analysis was performed with ANOVA and Tukey׳s tests.Results: SEM observation showed significant differences of the hybrid layer thickness between primary and permanent teeth under equal conditions and after different etching time. Group 6 presented the highest average thickness 8.85 μ and group 1 the lowest average in hybrid layer 3.74 μ.Conclusion: In primary teeth the hybrid layer thickness increases with the increased etching time. The hybrid layer thickness in primary teeth is greater than that of the hybrid layer in permanent teeth under equal conditions. For primary teeth it is more appropriate to reduce the etching time to 7s to obtain a hybrid layer with better quality

  14. Study on the Levitation and Restoring Force Characteristics of the Improved HTS-permanent Magnet Hybrid Magnetic Bearing

    Science.gov (United States)

    Sugiyama, R.; Oguni, K.; Ohashi, S.

    We have developed the hybrid magnetic bearing using permanent magnets and high temperature bulk super conductor (HTS). In this system, the permanent magnet has ring type structure so that the permanent magnet and the HTS can be set to the stator. The pinning force of the HTS is used for the levitation and the guidance. Repulsive force of the permanent magnets was used in the conventional hybrid system. However the restoring force in the guidance direction of the conventional hybrid system decreases by the side slip force of the permanent magnets. In this research, attractive force of permanent magnets is used for increasing the load weight in the guidance direction. In this paper, influence of the hybrid system on the static characteristics of the rotor is studied. Three-dimensional numerical analysis of the linkage flux (in the levitation and the guidance direction) in the HTS is undertaken. The stator side permanent magnet increases the linkage flux of the levitation direction. Therefore in the hybrid system the linkage flux of the levitation direction increases. The levitation and restoring force of the rotor is measured. The levitation force of the hybrid system becomes smaller than that of the non-hybrid one by attractive force. The rotor in the hybrid system is supported by the pinning force and attractive force. The restoring force of the hybrid system becomes larger than that of the non-hybrid one because of increasing the linkage flux of the levitation direction.

  15. CURRENT VECTOR CONTROL OF PERMANENT-MAGNET SYNCHRONOUS MOTOR OF HYBRID VEHICLE ENGINE

    Directory of Open Access Journals (Sweden)

    S. Serikov

    2009-01-01

    Full Text Available Characteristics of traction permanent-magnet synchronous motor under current vector optimum control in the possible traction-speed mode area which are relevant for hybrid vehicle engine have been investigated. As a criterion of optimality a maximum of electromagnetic moment per unit of current have been taken.

  16. Rotational characteristics in the resonance state of the HTSC-permanent magnet hybrid magnetic bearing

    Science.gov (United States)

    Morii, Y.; Sukedai, M.; Ohashi, S.

    2011-11-01

    The hybrid magnetic bearing using permanent magnets and the high-Tc bulk superconductor (HTSC) has been developed. Repulsive force of the permanent magnet is introduced to increase the load weight of the magnetic bearing. Effect of the hybrid system has been shown. In this paper, influence of the hybrid system on the dynamic characteristics of the rotor is studied. The rotational characteristics in the mechanical resonance state are studied, and the equivalent magnetic spring coefficient is estimated from the experimental results of the load weight. The resonance frequency is measured by the rotation experiments. The rotor achieves stable levitation even in the resonance state. In the hybrid system, effect of the pinning force becomes smaller than that of the lateral force generated by the repulsive force between the two permanent magnets at the smaller air gap. Thus influence of the lateral vibration and the gradient angle in the resonance state becomes larger at a smaller air gap. The equivalent magnetic spring coefficient becomes also small, and the resonance frequency becomes small in the hybrid bearing system.

  17. Modeling of Hybrid Permanent Magnetic-Gas Bearings

    DEFF Research Database (Denmark)

    Morosi, Stefano; Santos, Ilmar

    2009-01-01

    Modern turbomachinery applications require nowadays ever-growing rotational speeds and high degree of reliability. It then becomes natural to focus the attention of the research to contact-free bearings elements. The present alternatives focus on gas lubricated journal bearings or magnetic bearings...... concentric rings with radial magnetic orientation - analytical expressions for the calculation of the magnetic flux density and forces are employed, opposed to the main literature trend where finite element software is utilized at least for the calculation of the B-field. Numerical analysis shows how...... the rotor equilibrium position can be made independent on the rotational speed and applied load; it becomes function of the passive magnetic bearing offset. By adjusting the offset it is possible to significantly influence the dynamic coefficients of the hybrid bearing....

  18. Design Features of a Planar Hybrid/Permanent Magnet Strong Focusing Undulator for Free Electron Laser (FEL) And Synchrotron Radiation (SR) Applications

    Energy Technology Data Exchange (ETDEWEB)

    Tatchyn, Roman; /SLAC

    2011-09-09

    Insertion devices for Angstrom-wavelength Free Electron Laser (FEL) amplifiers driven by multi-GeV electron beams generally require distributed focusing substantially stronger than their own natural focusing fields. Over the last several years a wide variety of focusing schemes and configurations have been proposed for undulators of this class, ranging from conventional current-driven quadrupoles external to the undulator magnets to permanent magnet (PM) lattices inserted into the insertion device gap. In this paper we present design studies of a flexible high-field hybrid/PM undulator with strong superimposed planar PM focusing proposed for a 1.5 Angstrom Linac Coherent Light Source (LCLS) driven by an electron beam with a 1 mm-mr normalized emittance. Attainable field parameters, tuning modes, and potential applications of the proposed structure are discussed.

  19. Improvement of the Levitation Characteristics in the Magnetic Bearing System Using HTSC-Permanent Magnet Hybrid Structure

    Science.gov (United States)

    Ohashi, Shunsuke

    Magnetic bearing using pining force of a permanent magnet and a high-temperature superconductor has been developed. Additional permanent magnet is introduced to increase the levitation force of the magnetic bearing. In this hybrid magnetic bearing system, levitation force is mainly given by the repulsive force of the permanent magnets, and stability for the lateral direction is given by pining force of the superconductor. The experimental device is developed. A ring type superconductor and a bulk one are examined. Levitation characteristics of the hybrid magnetic bearing are measured. A bulk superconductor shows better characteristics both levitation and lateral stability than ring one. Levitation force of the hybrid system becomes about twice as large as that of the no-hybrid one. Although repulsive force of the permanent magnet decreases lateral stability of the system, its influence becomes small by choosing adequate position of the permanent magnets and the superconductor.

  20. Hybrid model predictive control for speed control of permanent magnet synchronous motor with saturation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A discrete-time hybrid model of a permanent magnet synchronous motor (PMSM) with saturation in voltage and current is formulated.The controller design with incorporated constraints is achieved in a systematic way from modeling to control synthesis and implementation.The Hybrid System Description Language is used to obtain a mixed-logical dynamical (MLD) model.Based on the MLD model,a model predictive controller is designed for an optimal speed regulation of the motor.For reducing computation complexity and ...

  1. MODELLING AND TORQUE TRACKING CONTROL OF PERMANENT MAGNET SYNCHRONOUS MOTOR FOR HYBRID ELECTRIC VEHICLES

    Directory of Open Access Journals (Sweden)

    Mohd Sabirin Rahmat

    2013-06-01

    Full Text Available This paper presents a detailed derivation of a permanent magnet synchronous motor, which may be used as the electric power train for the simulation of a hybrid electric vehicle. A torque tracking control of the permanent magnet synchronous motor is developed by using an adaptive proportional-integral-derivative controller. Several tests such as step function, saw tooth function, sine wave function and square wave function were used in order to examine the performance of the proposed control structure. The effectiveness of the proposed controller was verified and compared with the same system under a PID controller and the desired control. The result of the observations shows that the proposed control structure proves to be effective in tracking the desired torque with a good response. The findings of this study will be considered in the design, optimisation and experimentation of series hybrid electric vehicle.

  2. Improvement of the rotational characteristics in the HTSC-permanent magnet hybrid bearing using ring shaped magnet

    Energy Technology Data Exchange (ETDEWEB)

    Emoto, Kozo; Sugiyama, Ryo; Takagi, Shogo; Ohashi, Shunsuke, E-mail: k145676@kansai-u.ac.jp

    2013-11-15

    Highlights: •We have developed the HTS-permanent magnet hybrid bearing system. •Three dimensional numerical analysis is undertaken to get the effective hybrid configuration. •Repulsive force and pinning force are combined effectively. •The hybrid system shows better levitation characteristics than the non-hybrid one. •In the mechanical resonance state, vibration of the rotor in the hybrid system is small. -- Abstract: We have developed the hybrid magnetic bearing using permanent magnets and the high-T{sub c} bulk superconductor (HTSC). Pinning force of the HTSC is used for the levitation and the guidance. Repulsive force of the permanent magnets is introduced to increase the load weight of the magnetic bearing. In this system, the stator side permanent magnet has the ring type structure so that both pinning force and repulsive force are used effectively. In this paper, influence of the hybrid system on dynamic characteristics of the rotor is studied. The rotor which is supported by the hybrid magnetic bearing is rotated. Then, vibration and the gradient angle of the rotor are measured until the rotor reaches to the end of the resonance state. Three dimensional numerical analysis of the flux which penetrates on the surface of the HTSC is undertaken. The relation between the dynamic characteristics and the flux is considered, and that of the hybrid system is compared with the non-hybrid one. In the hybrid system, the flux is changed by the influences of the stator side permanent magnet. Vibration and the gradient angle of the hybrid system are shown to be smaller than that of the non-hybrid one.

  3. Research on Operation Principle and Control of Novel Hybrid Excitation Bearingless Permanent Magnet Generator

    Directory of Open Access Journals (Sweden)

    Huangqiu Zhu

    2016-08-01

    Full Text Available Under the condition of load changing, the magnetic field of traditional permanent magnet generators (PMG is hard to be adjusted, and the mechanical bearings are significantly worn. To overcome the drawbacks above, a novel hybrid excitation bearingless permanent magnet generator (HEBPMG is proposed in this paper, which has integrated the merits of hybrid excitation permanent magnet generators and magnetic bearings. Firstly, the structure and winding configuration of the HEBPMG are introduced, and then the principles of radial suspension and power generation are presented. The suspension principle as well as power generation principle is analyzed in this paper. Then, the flux linkage and induced voltage equations are derived, and the accurate mathematical model of radial suspension force is built based on the Maxwell tensor method. Subsequently, by means of the finite element analysis software-ANSYS Maxwell, the corresponding electromagnetic characteristics are analyzed to verify the correctness of the mentioned models. In addition, a compensation control strategy based on flux-linkage observation is proposed to solve the problems of unstable suspension force and generating voltage under variable load condition in this paper. Meanwhile, the corresponding control system is constructed and its feasibility is validated by simulation results. Finally, an experimental prototype of a 2.2 kW HEBPMG is tested. Experimental researches show that the HEBPMG can operate steadily under variable load condition and possess good suspension performance and power generation quality.

  4. Improvement of the rotational characteristics in the HTSC-permanent magnet hybrid bearing using ring shaped magnet

    Science.gov (United States)

    Emoto, Kozo; Sugiyama, Ryo; Takagi, Shogo; Ohashi, Shunsuke

    2013-11-01

    We have developed the hybrid magnetic bearing using permanent magnets and the high-Tc bulk superconductor (HTSC). Pinning force of the HTSC is used for the levitation and the guidance. Repulsive force of the permanent magnets is introduced to increase the load weight of the magnetic bearing. In this system, the stator side permanent magnet has the ring type structure so that both pinning force and repulsive force are used effectively. In this paper, influence of the hybrid system on dynamic characteristics of the rotor is studied. The rotor which is supported by the hybrid magnetic bearing is rotated. Then, vibration and the gradient angle of the rotor are measured until the rotor reaches to the end of the resonance state. Three dimensional numerical analysis of the flux which penetrates on the surface of the HTSC is undertaken. The relation between the dynamic characteristics and the flux is considered, and that of the hybrid system is compared with the non-hybrid one. In the hybrid system, the flux is changed by the influences of the stator side permanent magnet. Vibration and the gradient angle of the hybrid system are shown to be smaller than that of the non-hybrid one.

  5. Torque Analysis of Permanent Magnet Hybrid Stepper Motor using Finite Element Method for Different Design Topologies

    Directory of Open Access Journals (Sweden)

    E.V.C Sekhara Rao

    2012-01-01

    Full Text Available This paper discusses about permanent magnet hybrid stepper motor magnetic circuit using finite element model for different geometric designs like uniform air-gap, non uniform air-gap, for different air-gap lengths, different tooth pitches and extra teeth on stator using PDE toolbox of Matlab at different current densities. Implementing these results in equivalent circuit model (permeance model, motor performance is analyzed for an existing motor for steady state conditions. These results suggest modifications for better performance of the PMH stepper motor like reduction of cogging torque and improvement in steady state torque with minimum THD.

  6. Initial position estimation strategy for a surface permanent magnet synchronous motor used in hybrid electric vehicles

    Institute of Scientific and Technical Information of China (English)

    Bing TIAN; Qun-tao AN; Li SUN‡; Dong-yang SUN; Jian-dong DUAN

    2016-01-01

    A novel nonlinear model for surface permanent magnet synchronous motors (SPMSMs) is adopted to estimate the initial rotor position for hybrid electric vehicles (HEVs). Usually, the accuracy of initial rotor position estimation for SPMSMs relies on magnetic saturation. To verify the saturation effect, the transient finite element analysis (FEA) model is presented first. Hybrid injection of a static voltage vector (SVV) superimposed with a high-frequency rotating voltage is proposed. The magnetic polarity is roughly identified with the aid of the saturation evaluation function, based on which an estimation of the position is performed. During this procedure, a special demodulation is suggested to extract signals of iron core saturation and rotor position. A Simulink/MATLAB platform for SPMSMs at standstill is constituted, and the effectiveness of the proposed strategy is verified. The proposed method is also validated by experimental results of an SPMSM drive.

  7. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer.

    Science.gov (United States)

    Zacek, Petr; Bukowski, Michael; Rosenberger, Thad A; Picklo, Matthew

    2016-12-01

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PCs. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PCs. This approach is comprised of two MS methods: a precursor ion scanning (PIS) of mass m/z 184 in positive mode (PIS m/z +184) and MS(3) fragmentation in negative mode, both performed on the same instrument, a hybrid triple quadrupole ion-trap mass spectrometer. The MS(3) experiment identified the FA composition and the relative abundance of isobaric and sn-1, sn-2 positional isomeric PC species, which were subsequently combined with absolute quantitative data obtained by PIS m/z +184 scan. This approach was applied to the analysis of a National Institute of Standards and Technology human blood plasma standard reference material (SRM 1950). We quantified more than 70 PCs and confirmed that a majority are present in isobaric and isomeric mixtures. The FA content determined by this method was comparable to that obtained using GC with flame ionization detection, supporting the quantitative nature of this MS method. This methodology will provide more in-depth biomarker information for clinical and mechanistic studies.

  8. Importance of permanent improvement of production and control of basic seed of ZP maize hybrids

    Directory of Open Access Journals (Sweden)

    Sečanski Mile

    2015-01-01

    Full Text Available High-quality seed is one of the key factors in the commercial maize grain production. In addition, hybrid seed production is conditioned by the production of basic seed of parental inbreds. According to the Law on Seed, 2005, the category of basic seed is defined as: original of self-pollinated plant species, hybrid components and potato elite, produced under control of the Ministry competent for agribusiness and is used for the production of certified seed of the first generation. This paper presents a chronological overview of the overall activity since1945. that led to the modern production of maize seed in our country. The activities have been based on scientific, technical and technological achievements within many fields, ranging from genetics and breeding, through growing practices, processing, quality control and legal regulations concerning all of this. Transition from maize breeding and production to hybrids has provided an amazing development of maize breeding and seed production and also included significant profit. Therefore, maize seed production has become high-technology industry. The scientific and professional work in improving the production of basic seed of ZP maize hybrids has been carried out in stages, and generally followed achievements in maize breeding and genetics, as well as developments in the growing practices and processing. In order to maintain a high quality of maize hybrid seed, as the end product, permanent efforts have to be invested into maize production improvement, drying, processing, storing, genetic purity of basic seed of parental inbreds of ZP maize hybrids, which are grown on the significant percentage of maize production areas not only in Serbia and countries in the region.

  9. Design,analysis and control of hybrid excited doubly salient stator-permanent-magnet motor

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,a new hybrid excited doubly salient stator-permanent-magnet motor is proposed,where both permanent magnets and DC field windings are located in the stator.In theory,the mathematical model and design method of the motor are developed.The corresponding output power equation and the relationship between the flux control capability and the extended speed range are deduced in details.By using an efficient "one-step" three-dimensional(3D) finite element method,the electromagnetic performances are analyzed,in which the leakage flux outside the stator circumference and end-effect are taken into account.Based on the operation principle of the motor,the control strategy and scheme are developed and implemented experimentally.Both experimental results and finite element analysis show that the proposed motor not only maintains the advantages of doubly salient permanent magnet motors,but also offers high energy efficiency over a wide speed range,which makes the motor an interesting candidate for electric vehicles.

  10. Basic Characteristics of the Propulsion System in the Permanent Magnet-HTSC Hybrid Magnetic Conveyance System

    Science.gov (United States)

    Ohashi, Shunsuke; Kumano, Daiki; Goto, Yasuyuki

    The Hybrid magnetically levitated transportation system has been developed. The magnetic rail is set on the ground, and the carrier with permanent magnets and high-Tc superconductors (HTSC) levitates on the rail. Repulsive force of permanent magnet is introduced to support load weight. Pinning force of the HTSC is used to support weight of the frame of the carrier and to achieve lateral stability of the carrier. In this paper, propulsion system of the conveyance system is studied. Propulsion function is installed on the carrier body. Magnetic gradient is used to get propulsion force. Propulsion force of the system is little. So propulsion rail system is introduced. Air core copper coils are installed on the magnetic rail. Interaction between current of these coils and permanent magnets on the carrier generates propulsion force. Enough propulsion force is given. Influence of the propulsion system on the levitation and guidance system is measured. Stability of levitation and guidance system is enough even when propulsion system is operated.

  11. Levitation and Guidance Characteristics of the Permanent magnet-HTSC Hybrid Magnetic Conveyance System

    Science.gov (United States)

    Ohashi, Shunsuke; Dodo, Daiki

    Hybrid magnetically levitated transportation system has been developed. The magnetic rail is set on the ground, and the carrier with permanent magnets and high-Tc superconductors (HTSC) levitates on the rail. In this system, pinning force of HTSC and repulsive force of permanent magnet is combined. Repulsive force of permanent magnet is introduced to support weight. Pinning force is used to support weight of the frame of the carrier and to achieve lateral stability of the carrier. To decrease influence of weight on the levitation gap of the carrier, the weight stage is fixed to the carrier frame by linear sliders, and moves freely for vertical direction. As a result, there is little influence on levitation gap of the carrier. Basic levitation and guidance characteristics of the system are shown. Repulsive force generates very large levitation force. It also generates unstable lateral force. Weight added to the carrier has some influence on lateral stability. Although lateral position recovery force by pinning effect decreases at a heavier weight, the carrier shows enough force to keep lateral stability.

  12. Optimization design of an interior permanent-magnet synchronous machine for a hybrid hydraulic excavator

    Institute of Scientific and Technical Information of China (English)

    Qi-huai CHEN; Qing-feng WANG; Tao WANG

    2015-01-01

    A hybrid power transmission system (HPTS) is a promising way to save energy in a hydraulic excavator and the electric machine is one of the key components of the system. In this paper, a design process for permanent-magnet synchronous machines (PMSMs) in a hybrid hydraulic excavator (HHE) is presented based on the analysis of the working conditions and requirements of an HHE. A parameterized design approach, which combines the analytical model and the 2D finite element method (FEM), is applied to the electric machine to improve the design efficiency and accuracy. The analytical model is employed to optimize the electric machine efficiency and obtain the stator dimension and flux density distribution. The rotor is designed with the FEM to satisfy the flux requirements obtained in stator design. The rotor configuration of the PMSM employs an interior magnet structure, thus resulting in some inverse saliency, which allows for much higher values in magnetic flux density. To reduce the rotor leakage, a disconnected type silicon steel block structure is adopted. To improve the air gap flux density distribution, the trapezoid permanent magnet (PM) and centrifugal rotor structure are applied to PMSM. Demagnetization and armature reactions are also taken into consideration and calculated by the FEM. A prototype of the newly designed electric machine has been fabri-cated and tested on the experimental platform. The analytical design results are validated by measurements.

  13. Comparison between triple quadrupole, time of flight and hybrid quadrupole time of flight analysers coupled to liquid chromatography for the detection of anabolic steroids in doping control analysis.

    Science.gov (United States)

    Pozo, Oscar J; Van Eenoo, Peter; Deventer, Koen; Elbardissy, Hisham; Grimalt, Susana; Sancho, Juan V; Hernandez, Felix; Ventura, Rosa; Delbeke, Frans T

    2011-01-17

    Triple quadrupole (QqQ), time of flight (TOF) and quadrupole-time of flight (QTOF) analysers have been compared for the detection of anabolic steroids in human urine. Ten anabolic steroids were selected as model compounds based on their ionization and the presence of endogenous interferences. Both qualitative and quantitative analyses were evaluated. QqQ allowed for the detection of all analytes at the minimum required performance limit (MRPL) established by the World Anti-Doping Agency (between 2 and 10 ng mL(-1) in urine). TOF and QTOF approaches were not sensitive enough to detect some of the analytes (3'-hydroxy-stanozolol or the metabolites of boldenone and formebolone) at the established MRPL. Although a suitable accuracy was obtained, the precision was unsatisfactory (RSD typically higher than 20%) for quantitative purposes irrespective of the analyser used. The methods were applied to 30 real samples declared positives either for the misuse of boldenone, stanozolol and/or methandienone. Most of the compounds were detected by every technique, however QqQ was necessary for the detection of some metabolites in a few samples. Finally, the possibility to detect non-target steroids has been explored by the use of TOF and QTOF. The use of this approach revealed that the presence of boldenone and its metabolite in one sample was due to the intake of androsta-1,4,6-triene-3,17-dione. Additionally, the intake of methandienone was confirmed by the post-target detection of a long-term metabolite.

  14. A tubular hybrid Halbach/axially-magnetized permanent-magnet linear machine

    Directory of Open Access Journals (Sweden)

    Yi Sui

    2017-05-01

    Full Text Available A single-phase tubular permanent-magnet linear machine (PMLM with hybrid Halbach/axially-magnetized PM arrays is proposed for free-piston Stirling power generation system. Machine topology and operating principle are elaborately illustrated. With the sinusoidal speed characteristic of the free-piston Stirling engine considered, the proposed machine is designed and calculated by finite-element analysis (FEA. The main structural parameters, such as outer radius of the mover, radial length of both the axially-magnetized PMs and ferromagnetic poles, axial length of both the middle and end radially-magnetized PMs, etc., are optimized to improve both the force capability and power density. Compared with the conventional PMLMs, the proposed machine features high mass and volume power density, and has the advantages of simple control and low converter cost. The proposed machine topology is applicable to tubular PMLMs with any phases.

  15. A tubular hybrid Halbach/axially-magnetized permanent-magnet linear machine

    Science.gov (United States)

    Sui, Yi; Liu, Yong; Cheng, Luming; Liu, Jiaqi; Zheng, Ping

    2017-05-01

    A single-phase tubular permanent-magnet linear machine (PMLM) with hybrid Halbach/axially-magnetized PM arrays is proposed for free-piston Stirling power generation system. Machine topology and operating principle are elaborately illustrated. With the sinusoidal speed characteristic of the free-piston Stirling engine considered, the proposed machine is designed and calculated by finite-element analysis (FEA). The main structural parameters, such as outer radius of the mover, radial length of both the axially-magnetized PMs and ferromagnetic poles, axial length of both the middle and end radially-magnetized PMs, etc., are optimized to improve both the force capability and power density. Compared with the conventional PMLMs, the proposed machine features high mass and volume power density, and has the advantages of simple control and low converter cost. The proposed machine topology is applicable to tubular PMLMs with any phases.

  16. Presentation and Performance Evaluation of a Novel Stator-Permanent-Magnet Hybrid Stepping Motor

    Directory of Open Access Journals (Sweden)

    Binglin Lu

    2017-05-01

    Full Text Available In this paper, a new type of hybrid stepping motor (HSM with permanent magnets (PMs embedded in the stator, namely the stator-permanent-magnet hybrid stepping motor (SHSM, is presented. It has the same operation principles as the traditional HSM, with a 2-D distributed magnetic field nature and superiorities such as simpler rotor structure, easier PM cooling, higher torque and power density, and higher power grade. Its structural topology and operation principles are initially presented. Then an investigation on the performance comparison between the HSM and the SHSM, in terms of PM flux density, PM torque, detent torque, positional holding accuracy, stator core saturation issue, PM flux leakage, and PM utilization rate is carried out theoretically to make an assessment of the performance superiorities of the SHSM. A prototype of a 2-phase 8-pole 50-rotor-tooth SHSM is fabricated and experimentally compared with the HSM by using finite element analysis (FEA to verify the motor’s operational feasibility and the theoretical analysis. The FEA and experimental results show that the proposed SHSM has performance advantages such as higher torque density, higher power grade, and higher pull-out torque, holding torque, and torque-speed property, although it has performance defects such as higher torque ripple and relatively lower positional holding accuracy in the open-loop operation than the conventional HSM. Consequently, this novel SHSM is more suitable for electromechanical energy conversion applications rather than positioning mechanisms, especially taking into account the open-loop control advantage.

  17. A dual-channel flux-switching permanent magnet motor for hybrid electric vehicles

    Science.gov (United States)

    Hua, Wei; Wu, Zhongze; Cheng, Ming; Wang, Baoan; Zhang, Jianzhong; Zhou, Shigui

    2012-04-01

    The flux-switching permanent magnet (FSPM) motor is a relatively novel brushless machine having both magnets and concentrated windings in the stator, which exhibits inherently sinusoidal PM flux-linkage, back-EMF waveforms, and high torque capability. However, in the application of hybrid electric vehicles, it is essential to prevent magnets and armature windings moving in radial direction due to the possible vibration during operation, and to ensure fault-tolerant capability. Hence, in this paper based on an original FSPM motor, a dual-channel FSPM (DC-FSPM) motor with modified structure to fix both armature windings and magnets and improved reliability is proposed for a practical 10 kW integral starter/generator (ISG) in hybrid electric vehicles. The influences of different solutions and the end-effect on the static characteristics, are evaluated based on the 2D and 3D finite element analysis, respectively. Finally, both the predicted and experimental results, compared with a prototype DC-FSPM motor and an interior PM motor used in Honda Civic, confirm that the more sinusoidal back-EMF waveform and lower torque ripple can be achieved in the DC-FSPM motor, whereas the torque is smaller under the same coil current.

  18. A hybrid analytical model for open-circuit field calculation of multilayer interior permanent magnet machines

    Science.gov (United States)

    Zhang, Zhen; Xia, Changliang; Yan, Yan; Geng, Qiang; Shi, Tingna

    2017-08-01

    Due to the complicated rotor structure and nonlinear saturation of rotor bridges, it is difficult to build a fast and accurate analytical field calculation model for multilayer interior permanent magnet (IPM) machines. In this paper, a hybrid analytical model suitable for the open-circuit field calculation of multilayer IPM machines is proposed by coupling the magnetic equivalent circuit (MEC) method and the subdomain technique. In the proposed analytical model, the rotor magnetic field is calculated by the MEC method based on the Kirchhoff's law, while the field in the stator slot, slot opening and air-gap is calculated by subdomain technique based on the Maxwell's equation. To solve the whole field distribution of the multilayer IPM machines, the coupled boundary conditions on the rotor surface are deduced for the coupling of the rotor MEC and the analytical field distribution of the stator slot, slot opening and air-gap. The hybrid analytical model can be used to calculate the open-circuit air-gap field distribution, back electromotive force (EMF) and cogging torque of multilayer IPM machines. Compared with finite element analysis (FEA), it has the advantages of faster modeling, less computation source occupying and shorter time consuming, and meanwhile achieves the approximate accuracy. The analytical model is helpful and applicable for the open-circuit field calculation of multilayer IPM machines with any size and pole/slot number combination.

  19. CFD Modelling of a Quadrupole Vortex Inside a Cylindrical Channel for Research into Advanced Hybrid Rocket Designs

    Science.gov (United States)

    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.

  20. Qualitative and quantitative determination of YiXinShu Tablet using ultra high performance liquid chromatography with Q Exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometry.

    Science.gov (United States)

    Sun, Zhi; Li, Zhuolun; Zuo, Lihua; Wang, Zhenhui; Zhou, Lin; Shi, Yingying; Kang, Jian; Zhu, Zhenfeng; Zhang, Xiaojian

    2017-08-24

    To clarify and quantify the chemical profile of YiXinShu Tablet rapidly, a feasible and accurate strategy was developed by applying ultra high performance liquid chromatography with Q Exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometry. A total of 105 components were identified, including 25 phenanthraquinones, 11 lactones, 19 lignans, 24 acids and 26 other compounds. Among them, 26 major compounds were unambiguously detected by comparing with reference standards. And 19 of these compounds in three batches of YiXinShu Tablet were selected for quantitative determination. (Z)-Ligustilide, salvianic acid A, salvianolic acid A, salvianolic acid B and rosmarinic acid were abundant in these three batches with contents over 1.000 mg/g. The established analysis methods were examined to be accurate and feasible. The results show that the ultra high performance liquid chromatography with Q Exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometry method has a powerful qualitative ability and promising quantitative application. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Comparison of triple quadrupole, hybrid linear ion trap triple quadrupole, time-of-flight and LTQ-Orbitrap mass spectrometers in drug discovery phase metabolite screening and identification in vitro--amitriptyline and verapamil as model compounds.

    Science.gov (United States)

    Rousu, Timo; Herttuainen, Jukka; Tolonen, Ari

    2010-04-15

    Liquid chromatography in combination with mass spectrometry (LC/MS) is a superior analytical technique for metabolite profiling and identification studies performed in drug discovery and development laboratories. In the early phase of drug discovery the analytical approach should be both time- and cost-effective, thus providing as much data as possible with only one visit to the laboratory, without the need for further experiments. Recent developments in mass spectrometers have created a situation where many different mass spectrometers are available for the task, each with their specific strengths and drawbacks. We compared the metabolite screening properties of four main types of mass spectrometers used in analytical laboratories, considering both the ability to detect the metabolites and provide structural information, as well as the issues related to time consumption in laboratory and thereafter in data processing. Human liver microsomal incubations with amitriptyline and verapamil were used as test samples, and early-phase 'one lab visit only' approaches were used with all instruments. In total, 28 amitriptyline and 69 verapamil metabolites were found and tentatively identified. Time-of-flight mass spectrometry (TOFMS) was the only approach detecting all of them, shown to be the most suitable instrument for elucidating as comprehensive metabolite profile as possible leading also to lowest overall time consumption together with the LTQ-Orbitrap approach. The latter however suffered from lower detection sensitivity and false negatives, and due to slow data acquisition rate required slower chromatography. Approaches with triple quadrupole mass spectrometry (QqQ) and hybrid linear ion trap triple quadrupole mass spectrometry (Q-Trap) provided the highest amount of fragment ion data for structural elucidation, but, in addition to being unable to produce very high-important accurate mass data, they suffered from many false negatives, and especially with the Qq

  2. A Novel Integral 5-DOFs Hybrid Magnetic Bearing with One Permanent Magnet Ring Used for Turboexpander

    Directory of Open Access Journals (Sweden)

    Bangcheng Han

    2014-01-01

    Full Text Available We propose a novel combined five-degrees-of-freedom (5-DOFs hybrid magnetic bearing (HMB with only one permanent magnet ring (PMR used for turboexpanders. It has two radial magnetic bearing (RMB units; each has four poles and one thrust magnetic bearing (TMB to control 5-DOFs. Based on one PMR, the bias flux of the two radial magnetic bearing units and the one thrust magnetic bearing unit is constructed. As a result, ultra-high-speed, lower power loss, small size, and low cost can be achieved. Furthermore, the equivalent magnetic circuit method and 3D finite element method (FEM are used to model and analyze the combined 5-DOFs HMB. The force-current, force-position, torque-coil currents, the torque-angle position, and the stiffness models of the combined 5-DOFs HMB are given. Moreover, its coupling problems between the RMB units and the AMB unit are also proposed in this paper. An example is given to clarify the mathematical models and the coupling problems, and the linearized models are proposed for the follow-up controller design.

  3. Study on control method of running velocity for the permanent magnet-HTSC hybrid magnetically levitated conveyance system

    Science.gov (United States)

    Nishio, R.; Ikeda, M.; Sasaki, R.; Ohashi, S.

    2011-11-01

    We have developed the magnetically levitated carrying system. In this system, pinning force of high temperature bulk super conductor (HTSC) is used for the levitation and guidance. Four HTSCs are installed on the carrier. The magnetic rail is set on the ground, and flux from the magnetic rail is pinned by HTSCs. To increase levitation force, repulsive force of the permanent magnet is used. The hybrid levitation system is composed. The permanent magnet is installed under the load stage of the carrier. Repulsive force by the permanent magnet between the load stage on the carrier and the magnetic rail on the ground is used to support the load weight. Levitation and guidance one by pinning effect of the YBaCuO HTSC in the carrier is used to levitate the carrier body. The load stage is separated from the carrier flame and can move freely for vertical direction levitation. For the propulsion system, electromagnet is installed on the surface of the magnetic rail. In this paper, control method of running velocity of the carrier is studied. Propulsion force is given as follows; Air core copper coils are installed on the magnetic rail. Interaction between current of these coils and permanent magnets on the carrier generates propulsion force. Running velocity is controlled by current of the propulsion coils. It is also changed by position of the carrier and the load weight. From the results, stability of the propulsion system is given, and propulsion characteristics are improved.

  4. Study on control method of running velocity for the permanent magnet-HTSC hybrid magnetically levitated conveyance system

    Energy Technology Data Exchange (ETDEWEB)

    Nishio, R.; Ikeda, M.; Sasaki, R. [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Ohashi, S., E-mail: ohashi@kansai-u.ac.jp [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan)

    2011-11-15

    The hybrid magnetically levitated carrying system is developed. Control method of running velocity of the carrier is studied. Running velocity is controlled by current of the propulsion coils. Propulsion characteristcs are improved. We have developed the magnetically levitated carrying system. In this system, pinning force of high temperature bulk super conductor (HTSC) is used for the levitation and guidance. Four HTSCs are installed on the carrier. The magnetic rail is set on the ground, and flux from the magnetic rail is pinned by HTSCs. To increase levitation force, repulsive force of the permanent magnet is used. The hybrid levitation system is composed. The permanent magnet is installed under the load stage of the carrier. Repulsive force by the permanent magnet between the load stage on the carrier and the magnetic rail on the ground is used to support the load weight. Levitation and guidance one by pinning effect of the YBaCuO HTSC in the carrier is used to levitate the carrier body. The load stage is separated from the carrier flame and can move freely for vertical direction levitation. For the propulsion system, electromagnet is installed on the surface of the magnetic rail. In this paper, control method of running velocity of the carrier is studied. Propulsion force is given as follows; Air core copper coils are installed on the magnetic rail. Interaction between current of these coils and permanent magnets on the carrier generates propulsion force. Running velocity is controlled by current of the propulsion coils. It is also changed by position of the carrier and the load weight. From the results, stability of the propulsion system is given, and propulsion characteristics are improved.

  5. Comprehensive lipidome analysis by shotgun lipidomics on a hybrid quadrupole-orbitrap-linear ion trap mass spectrometer

    DEFF Research Database (Denmark)

    Almeida, Reinaldo; Pauling, Josch Konstantin; Sokol, Elena

    2015-01-01

    , including its high resolution power unsurpassed by any other contemporary Orbitrap instrumentation, its dynamic quantification range and its efficacy for in-depth structural characterization of molecular lipid species by quadrupole-based higher-energy collisional dissociation (HCD), and ion trap...... of fragmentation analysis demonstrated that combined use of HCD and CID yields complementary fragment ions of molecular lipid species. To support global lipidome analysis, we designed a method, termed MS(ALL), featuring high resolution FTMS analysis for lipid quantification, and FTMS(2) analysis using both HCD...... and CID and ITMS(3) analysis utilizing dual CID for in-depth structural characterization of molecular glycerophospholipid species. The performance of the MS(ALL) method was benchmarked in a comparative analysis of mouse cerebellum and hippocampus. This analysis demonstrated extensive lipidome...

  6. Comprehensive profiling of N-acylhomoserine lactones produced by Yersinia pseudotuberculosis using liquid chromatography coupled to hybrid quadrupole-linear ion trap mass spectrometry.

    Science.gov (United States)

    Ortori, Catharine A; Atkinson, Steve; Chhabra, Siri Ram; Cámara, Miguel; Williams, Paul; Barrett, David A

    2007-01-01

    A method for the comprehensive profiling of the N-acylhomoserine lactone (AHL) family of bacterial quorum-sensing molecules is presented using liquid chromatography (LC) coupled to hybrid quadrupole-linear ion trap (QqQLIT) mass spectrometry. Information-dependent acquisition (IDA), using triggered combinations of triple-quadrupole and linear ion trap modes in the same LC-MS/MS run, was used to simultaneously screen, quantify and identify multiple AHLs in a single sample. This MS method uses common AHL fragment ions attributed to the homoserine moiety and the 3-oxo-, 3-hydroxy- or unsubstituted acyl side chains, to identify unknown AHLs in cell-free culture supernatants in an unbiased manner. This LC-MS technique was applied to determine the relative molar ratios of AHLs produced by Yersinia pseudotuberculosis and the consequences of inactivating by mutation either or both of the AHL synthase genes (ypsI and ytbI) on AHL profile and concentration. The Y. pseudotuberculosis wild type but not the ypsI ytbI double mutant produced at least 24 different AHLs with acyl chains ranging from C4 to C15 with or without 3-oxo or 3-hydroxy substituents. YtbI, in contrast to YpsI, could direct the synthesis of all of the AHLs identified. The most abundant and hence most biologically relevant Y. pseudotuberculosis AHLs were found to be the 3-oxo-substituted C6, C7 and C8 AHLs and the unsubstituted C6 and C8 compounds. The LC-QqQLIT methodology is broadly applicable to quorum-sensing signal molecule analysis and can provide comprehensive AHL profiles and concentrations from a single sample and simultaneously collect confirmatory spectra for each AHL identified.

  7. Characteristic Analysis and Experimental Study of a Hybrid Permanent Magnet Variable Flux Memory Motor

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Variable flux permanent magnet (PM) memory motors (VFMM), which combine the advantages of PM machines with high power density and electrically excited machines with controllable air-gap magnetic flux, have been widely concerned and researched in recent years.

  8. Self-commissioning of permanent magnet synchronous machine drives using hybrid approach

    DEFF Research Database (Denmark)

    Basar, M. Sertug; Bech, Michael Møller; Andersen, Torben Ole

    2014-01-01

    Self-commissioning of permanent-magnet (PM) synchronous machines (PMSMs) is of prime importance in an industrial drive system because control performance and system stability depend heavily on the accurate machine parameter information. This article focuses on a combination of offline and online ...

  9. Shotgun Lipidomics by Sequential Precursor Ion Fragmentation on a Hybrid Quadrupole Time-of-Flight Mass Spectrometer

    Directory of Open Access Journals (Sweden)

    Brigitte Simons

    2012-02-01

    Full Text Available Shotgun lipidomics has evolved into a myriad of multi-dimensional strategies for molecular lipid characterization, including bioinformatics tools for mass spectrum interpretation and quantitative measurements to study systems-lipidomics in complex biological extracts. Taking advantage of spectral mass accuracy, scan speed and sensitivity of improved quadrupole linked time-of-flight mass analyzers, we developed a bias-free global lipid profiling acquisition technique of sequential precursor ion fragmentation called MS/MSALL. This generic information-independent tandem mass spectrometry (MS technique consists of a Q1 stepped mass isolation window through a set mass range in small increments, fragmenting and recording all product ions and neutral losses. Through the accurate MS and MS/MS information, the molecular lipid species are resolved, including distinction of isobaric and isomeric species, and composed into more precise lipidomic outputs. The method demonstrates good reproducibility and at least 3 orders of dynamic quantification range for isomeric ceramides in human plasma. More than 400 molecular lipids in human plasma were uncovered and quantified in less than 12 min, including acquisitions in both positive and negative polarity modes. We anticipate that the performance of sequential precursor ion fragmentation both in quality and throughput will lead to the uncovering of new avenues throughout the biomedical research community, enhance biomarker discovery and provide novel information target discovery programs as it will prospectively shed new insight into affected metabolic and signaling pathways.

  10. Analysis of psychoactive substances in water by information dependent acquisition on a hybrid quadrupole time-of-flight mass spectrometer.

    Science.gov (United States)

    Andrés-Costa, María Jesús; Andreu, Vicente; Picó, Yolanda

    2016-08-26

    Emerging drugs of abuse, belonging to many different chemical classes, are attracting users with promises of "legal" highs and easy access via internet. Prevalence of their consumption and abuse through wastewater-based epidemiology can only be realized if a suitable analytical screening procedure exists to detect and quantify them in water. Solid-phase extraction and ultra-high performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UHPLC-QqTOF-MS/MS) was applied for rapid suspect screening as well as for the quantitative determination of 42 illicit drugs and metabolites in water. Using this platform, we were able to identify amphetamines, tryptamines, piperazines, pyrrolidinophenones, arylcyclohexylamines, cocainics, opioids and cannabinoids. Additionally, paracetamol, carbamazepine, ibersartan, valsartan, sulfamethoxazole, terbumeton, diuron, etc. (including degradation products as 3-hydroxy carbamazepine or deethylterbuthylazine) were detected. This method encompasses easy sample preparation and rapid identification of psychoactive drugs against a database that cover more than 2000 compounds that ionized in positive mode, and possibility to identify metabolites and degradation products as well as unknown compounds. The method for river water, influent and effluents samples was fully validated for the target psychoactive substances including assessment of matrix effects (-88-67.8%), recovery (42-115%), precision (psychoactive drugs biomarkers and other water contaminants is demonstrated.

  11. Comprehensive lipidome analysis by shotgun lipidomics on a hybrid quadrupole-orbitrap-linear ion trap mass spectrometer.

    Science.gov (United States)

    Almeida, Reinaldo; Pauling, Josch Konstantin; Sokol, Elena; Hannibal-Bach, Hans Kristian; Ejsing, Christer S

    2015-01-01

    Here we report on the application of a novel shotgun lipidomics platform featuring an Orbitrap Fusion mass spectrometer equipped with an automated nanoelectrospray ion source. To assess the performance of the platform for in-depth lipidome analysis, we evaluated various instrument parameters, including its high resolution power unsurpassed by any other contemporary Orbitrap instrumentation, its dynamic quantification range and its efficacy for in-depth structural characterization of molecular lipid species by quadrupole-based higher-energy collisional dissociation (HCD), and ion trap-based resonant-excitation collision-induced dissociation (CID). This evaluation demonstrated that FTMS analysis with a resolution setting of 450,000 allows distinguishing isotopes from different lipid species and features a linear dynamic quantification range of at least four orders of magnitude. Evaluation of fragmentation analysis demonstrated that combined use of HCD and CID yields complementary fragment ions of molecular lipid species. To support global lipidome analysis, we designed a method, termed MS(ALL), featuring high resolution FTMS analysis for lipid quantification, and FTMS(2) analysis using both HCD and CID and ITMS(3) analysis utilizing dual CID for in-depth structural characterization of molecular glycerophospholipid species. The performance of the MS(ALL) method was benchmarked in a comparative analysis of mouse cerebellum and hippocampus. This analysis demonstrated extensive lipidome quantification covering 311 lipid species encompassing 20 lipid classes, and identification of 202 distinct molecular glycerophospholipid species when applying a novel high confidence filtering strategy. The work presented here validates the performance of the Orbitrap Fusion mass spectrometer for in-depth lipidome analysis.

  12. Development of a sensitive method for the determination of acrylamide in coffee using high-performance liquid chromatography coupled to a hybrid quadrupole Orbitrap mass spectrometer.

    Science.gov (United States)

    Pugajeva, Iveta; Jaunbergs, Janis; Bartkevics, Vadims

    2015-01-01

    The emerging trend towards high-resolution mass spectrometry (MS) alternatives was evaluated by the application of Orbitrap MS for the determination of acrylamide in coffee samples. The high resolving power of the Orbitrap MS provided the high selectivity and sensitivity that enabled quantitative analysis of acrylamide in complex matrices, such as coffee. Several sample preparation methods and scanning modes of the MS (full MS, t-SIM, t-MS2) were assessed in order to optimise parameters of the analytical method. The final procedure involved the extraction of acrylamide with acetonitrile, solid-phase extraction with dispersive primary secondary amine (PSA) and amino columns, and the detection by ultra-performance liquid chromatography coupled to a hybrid quadrupole-Orbitrap MS (HPLC-Q-Orbitrap) operated in targeted MS2 scanning mode. The repeatability of the method at the lowest calibration level (10 μg kg(-1)), expressed as relative standard deviation, was 7.8% and the average recovery of acrylamide was 111%. The proposed method was applied to the determination of acrylamide in 22 samples of roasted coffee obtained from the Latvian retail market. Acrylamide concentration in coffee samples was in the range of 166-503 μg kg(-1).

  13. Development and Validation of New Ultra-High-Performance Liquid Chromatography-Hybrid Quadrupole-Orbitrap Mass Spectrometry Method for Determination of Melatonin in Fruits.

    Science.gov (United States)

    Reinholds, Ingars; Pugajeva, Iveta; Radenkovs, Vitalijs; Rjabova, Jekaterina; Bartkevics, Vadims

    2016-07-01

    A new reliable analytical method based on ultra-high-performance liquid chromatography coupled with hybrid quadrupole-Orbitrap mass spectrometry was developed for the analysis of melatonin (MEL) in food products. In-house validation was performed using deuterated melatonin (MEL-d4) as an internal standard to ensure method selectivity and accuracy and to evaluate the efficiency of a robust ethyl acetate extraction technique used for sample preparation. The analysis of 18 tart cherry varieties and 28 tomato varieties was performed at optimized conditions. The method was linear (R(2)> 0.99) over the concentration range of 5-200 pg/g. A very low limit of quantification (10 pg/g) was provided for both analyzed matrices. The determined average recoveries (102 and 110%) and the values of intraday repeatability (6.30 and 10.9%) for cherry and tomato matrices, respectively, indicated a good accuracy and precision. The elaborated procedure proved the absence of MEL in any of tart cherries (Cherry," "Cherry Red" and "Rome" tomatoes grown in the Netherlands.

  14. Design of a Permanent Magnet Synchronous Machine for a Flywheel Energy Storage System within a Hybrid Electric Vehicle

    Science.gov (United States)

    Jiang, Ming

    As an energy storage device, the flywheel has significant advantages over conventional chemical batteries, including higher energy density, higher efficiency, longer life time, and less pollution to the environment. An effective flywheel system can be attributed to its good motor/generator (M/G) design. This thesis describes the research work on the design of a permanent magnet synchronous machine (PMSM) as an M/G suitable for integration in a flywheel energy storage system within a large hybrid electric vehicle (HEV). The operating requirements of the application include wide power and speed ranges combined with high total system efficiency. Along with presenting the design, essential issues related to PMSM design including cogging torque, iron losses and total harmonic distortion (THD) are investigated. An iterative approach combining lumped parameter analysis with 2D Finite Element Analysis (FEA) was used, and the final design is presented showing excellent performance.

  15. Modeling and Control of a Flux-Modulated Compound-Structure Permanent-Magnet Synchronous Machine for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Zhiyi Song

    2012-01-01

    Full Text Available The compound-structure permanent-magnet synchronous machine (CS-PMSM, comprising a double rotor machine (DRM and a permanent-magnet (PM motor, is a promising electronic-continuously variable transmission (e-CVT concept for hybrid electric vehicles (HEVs. By CS-PMSM, independent speed and torque control of the vehicle engine is realized without a planetary gear unit. However, the slip rings and brushes of the conventional CS-PMSM are considered a major drawback for vehicle application. In this paper, a brushless flux-modulated CS-PMSM is investigated. The operating principle and basic working modes of the CS-PMSM are discussed. Mathematical models of the CS-PMSM system are given, and joint control of the two integrated machines is proposed. As one rotor of the DRM is mechanically connected with the rotor of the PM motor, special rotor position detection and torque allocation methods are required. Simulation is carried out by Matlab/Simulink, and the feasibility of the control system is proven. Considering the complexity of the controller, a single digital signal processor (DSP is used to perform the interconnected control of dual machines instead of two separate ones, and a typical hardware implementation is proposed.

  16. Self-commissioning of permanent magnet synchronous machine drives using hybrid approach

    DEFF Research Database (Denmark)

    Basar, Mehmet Sertug

    2014-01-01

    Self-commissioning of permanent-magnet (PM) synchronous machines (PMSMs) is of prime importance in an industrial drive system because control performance and system stability depend heavily on the accurate machine parameter information. This article focuses on a combination of offline and online...... parameter estimation for a non-salient pole PMSM which eliminates the need for any prior knowledge on machine parameters. Stator resistance and inductance are first identified at standstill utilising fundamental and high-frequency excitation signals, respectively. A novel method has been developed...... and employed for inductance estimation. Then, stator resistance, inductance and PM flux are updated online using a recursive least-squares (RLS) algorithm. The proposed controllers are designed using MATLAB/Simulink® and implemented on d-Space® real-time system incorporating a commercially available PMSM drive....

  17. Analysis of 44 drugs of abuse and metabolites in wastewater and river water using a hybrid quadrupole time-of-flight tandem mass spectrometry

    Science.gov (United States)

    Andres-Costa, M. Jesus; Andreu, Vicente; Picó, Yolanda

    2016-04-01

    The presence of drugs of abuse in the aquatic environment has been recognized as an important issue for the ecosystem due their possible negative effect on it (Richardson, 2011). Incomplete removal of these substances during wastewater treatment could be one of the causes of their release in the environment (Zuccato and Castiglioni, 2009). Pollution by illicit drug residues at very low concentrations is generalized in populated areas, with potential risks for human health and the environment (Zuccato, 2008; Castiglioni et al 2007).The aim of this study was to screen and quantify 44 drugs of abuse and metabolites of wastewater samples using a hybrid quadrupole time-of-flight tandem mass spectrometry and furthermore carry out a post-target screening to identify additional compounds present in the water samples. Wastewater samples were collected from the influent and effluent of three wastewater treatment plants (WWTPs) in Valencia and river water samples form Turia River Basin. Illicit drugs were extracted by solid-phase extraction (SPE). The chromatography was performed with an Agilent 1260 Infinity ultra high performance liquid chromatography (UHPLC). The UHPLC system was coupled to a hybrid quadrupole time-of-flight ABSciex Triple TOFTM 5600. All analytes were analyzed in positive mode. Acquiring full scan MS data was employed for quantification of drugs of abuse, and automatic data dependent information product ion spectra (IDA-MS/MS) was checked for identifying emerging illicit drugs and other compounds in water samples. The use of a database containing 1212 compounds achieved high confidence results for a wide number of contaminants. In the present study, the presence of compounds that belong to amphetamines group (amphetamine, methamphetamine, ephedrine, MDMA, MDA and MDEA), tryptamines (bufotenine), pirrolidinophenone group (α-PVP and 4'-MePHP), arylcyclohexylamines (ketamine), cocainics (cocaine, benzoylecgonine, cocaethylene and ecgonine methyl ester) and

  18. A validated hybrid quadrupole linear ion-trap LC-MS method for the analysis of morphine and morphine glucuronides applied to opiate deaths.

    Science.gov (United States)

    Taylor, Kerry; Elliott, Simon

    2009-05-30

    A hybrid quadrupole linear ion-trap mass spectrometer using an electrospray ionisation ion source coupled to a HPLC system has been used to develop a method which can accurately measure morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in plasma, whole blood and post-mortem blood following solid-phase extraction. The method can also qualitatively detect various other opioids and related compounds including: codeine, dihydrocodeine (and metabolites), noscapine, papaverine and 6-acetylmorphine (6-AM). The method has been favourably compared to an existing laboratory method using a now discontinued radio-immunoassay technique. The advantage of measuring the glucuronides directly rather than following deconjugation by beta-glucuronidase has also been shown. Detection and quantification of compounds was achieved using multiple reaction monitoring (MRM) incorporating the use of deuterated morphine and M3G as internal standards. Precision and accuracy was determined to be less than 10% at both high and low levels for all analytes and the calibration curve was deemed linear over an acceptable range. Recovery in blood was greater than 90% and ion suppression/enhancement was shown to be less than 15%. This method was applied to over 130 post-mortem cases involving the use of heroin, prescribed morphine and codeine. The range of concentrations of morphine, M3G and M6G was large (particularly in heroin and prescribed morphine cases), reflecting the many different factors involved with therapeutic use or fatal opiate poisonings, including tolerance associated with regular use, variable dose regimens and co-administration of other drugs. Detection of other constituents of the opium poppy such as noscapine and papaverine and metabolites of diacetylmorphine in the blood (6-AM) was useful in determining the source of the morphine (i.e. illicit heroin) and the rapidity of death after administration.

  19. Multiple and sequential data acquisition method: an improved method for fragmentation and detection of cross-linked peptides on a hybrid linear trap quadrupole Orbitrap Velos mass spectrometer.

    Science.gov (United States)

    Rudashevskaya, Elena L; Breitwieser, Florian P; Huber, Marie L; Colinge, Jacques; Müller, André C; Bennett, Keiryn L

    2013-02-05

    The identification and validation of cross-linked peptides by mass spectrometry remains a daunting challenge for protein-protein cross-linking approaches when investigating protein interactions. This includes the fragmentation of cross-linked peptides in the mass spectrometer per se and following database searching, the matching of the molecular masses of the fragment ions to the correct cross-linked peptides. The hybrid linear trap quadrupole (LTQ) Orbitrap Velos combines the speed of the tandem mass spectrometry (MS/MS) duty circle with high mass accuracy, and these features were utilized in the current study to substantially improve the confidence in the identification of cross-linked peptides. An MS/MS method termed multiple and sequential data acquisition method (MSDAM) was developed. Preliminary optimization of the MS/MS settings was performed with a synthetic peptide (TP1) cross-linked with bis[sulfosuccinimidyl] suberate (BS(3)). On the basis of these results, MSDAM was created and assessed on the BS(3)-cross-linked bovine serum albumin (BSA) homodimer. MSDAM applies a series of multiple sequential fragmentation events with a range of different normalized collision energies (NCE) to the same precursor ion. The combination of a series of NCE enabled a considerable improvement in the quality of the fragmentation spectra for cross-linked peptides, and ultimately aided in the identification of the sequences of the cross-linked peptides. Concurrently, MSDAM provides confirmatory evidence from the formation of reporter ions fragments, which reduces the false positive rate of incorrectly assigned cross-linked peptides.

  20. Selenium metabolomics in yeast using complementary reversed-phase/hydrophilic ion interaction (HILIC) liquid chromatography-electrospray hybrid quadrupole trap/Orbitrap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Arnaudguilhem, C.; Bierla, K.; Ouerdane, L.; Preud' homme, H. [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-inorganique et Environnement, UMR 5254, Helioparc, 2, Av. Pr. Angot, 64053 Pau (France); Yiannikouris, A. [Alltech Inc., 3031 Catnip Hill Pike, Nicholasville, KY (United States); Lobinski, R., E-mail: ryszard.lobinski@univ-pau.fr [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-inorganique et Environnement, UMR 5254, Helioparc, 2, Av. Pr. Angot, 64053 Pau (France); Chair of Analytical Chemistry, Warsaw University of Technology, 00-664 Warszawa (Poland)

    2012-12-13

    Highlights: Black-Right-Pointing-Pointer The use of bimodal chromatographic separation enlarged amount of compounds identified. Black-Right-Pointing-Pointer The method allowed the largest scale ever (>60 compounds) speciation analysis of selenium metabolites in Se-rich yeast. Black-Right-Pointing-Pointer The estimated concentration of compounds was given. - Abstract: A high efficiency chromatographic separation on a porous graphitic carbon stationary phase was developed for a large-scale separation of selenium metabolites in Se-rich yeast prior to their identification by electrospray hybrid quadrupole trap/Orbitrap mass spectrometry (Orbitrap MS{sup n}). The reversed-phase (RP) separation mode offered distinctly higher separation efficiency than the hydrophilic ion interaction (HILIC) mode. The latter was nevertheless complementary and useful to validate the detection of several compounds. The method allowed the detection of 64 metabolites including 30 Se-Se or Se-S conjugates (3 triple S/Se/S ones) and 14 selenoethers. 21 previously unreported metabolites were detected on the basis of the selenium isotopic pattern usually matched with the sub-ppm mass accuracy. 9 of these metabolites were subsequently identified using the multi-stage high mass accuracy (<5 ppm) mass spectrometry. The identified metabolites (and their groups) were quantified on-line by ICP-MS fitted with a frequency-matching generator allowing a quasi-uniform response over the large (20-90%) acetonitrile mobile phase concentration range. The morphology of HPLC-ICP-MS chromatograms was remarkably similar to that of HPLC multi-ion extracted ESI-MS chromatograms. The detection limits obtained by ICP MS and ESI MS were 1 and 2 ppb, respectively.

  1. High-Energy Permanent Magnets for Hybrid Vehicles and Alternative Energy Uses

    Energy Technology Data Exchange (ETDEWEB)

    Hadjipanayis, George C. [University of Delaware; McCallum, William R. [Ames Laboratory; Sellmyer, David J. [University of Nebraska, Lincoln; Harris, Vincent [Northeastern University; Carpenter, Everett E. [Virginia Commonwealth University; Liu, Jinfang [Electron Energy Corporation

    2013-12-17

    The report summarizes research undertaken by a multidisciplinary team aimed at the development of the next generation high-energy permanent magnets. The principal approach was relied on bottom-up fabrication of anisotropic nanocomposite magnets. Our efforts resulted in further development of the theoretical concept and fabrication principles for the nanocomposites and in synthesis of a range of rare-earth-based hard magnetic nanoparticles. Even though we did not make a breakthrough in the assembly of these hard magnetic particles with separately prepared Fe(Co) nanoparticles and did not obtain a compact nanocomposite magnet, our performed research will help to direct the future efforts, in particular, towards nano-assembly via coating, when the two phases which made the nanocomposite are first organized in core-shell-structured particles. Two other approaches were to synthesize (discover) new materials for the traditional singe-material magnets and the nanocomposite magnets. Integrated theoretical and experimental efforts lead to a significant advance in nanocluster synthesis technique and yielded novel rare-earth-free nanostructured and nanocomposite materials. Examination of fifteen R-Fe-X alloy systems (R = rare earth), which have not been explored earlier due to various synthesis difficulties reveal several new ferromagnetic compounds. The research has made major progress in bottom-up manufacturing of rare-earth-containing nanocomposite magnets with superior energy density and open new directions in development of higher-energy-density magnets that do not contain rare earths. The advance in the scientific knowledge and technology made in the course of the project has been reported in 50 peer-reviewed journal articles and numerous presentations at scientific meetings.

  2. PM Axial Flux Machine Design for Hybrid Traction Conception d’une machine à flux axial à aimants permanents pour la traction hybride

    Directory of Open Access Journals (Sweden)

    de la Barrière O.

    2009-11-01

    Full Text Available the best ways in order to reduce fuel consumption for vehicles. It consists of associating an electric motor next to the classical thermal machine. In this embedded system, the efficiency and the torque per unit mass are very important. So it seems to be a good idea to use a permanent magnet synchronous machine, which is recognized for satisfying these two objectives. Since the allocated volume is rather flat, axial flux topologies are interesting. This paper’s goal is to propose an optimal first design method for such structures, given the allocated volume and the machine requirements. La traction hybride semble actuellement un des moyens les plus prometteurs pour réduire la consommation de carburant des véhicules. Ce procédé consiste à associer un moteur électrique au moteur thermique traditionnel. Pour une telle application embarquée, le rendement, ainsi que le couple massique, sont des critères de conception de première importance. Dans ce contexte, le recours à une machine synchrone à aimants permanents, reconnue pour satisfaire ces deux critères, semble être approprié. Vu que le volume alloué à la machine électrique est de forme discoïde, les topologies à flux axial semblent les plus intéressantes. L’objectif de cet article est de proposer une méthodologie de pré-dimensionnement de tels actionneurs, en ayant fixé au préalable le volume maximal permis ainsi que le cahier des charges de la machine.

  3. Shimming with permanent magnets for the x-ray detector in a hybrid x-ray/ MR system.

    Science.gov (United States)

    Wen, Zhifei; Fahrig, Rebecca; Williams, Scott T; Pelc, Norbert J

    2008-09-01

    In this x-ray/MR hybrid system an x-ray flat panel detector is placed under the patient cradle, close to the MR volume of interest (VOI), where the magnetic field strength is approximately 0.5 T. Immersed in this strong field, several electronic components inside the detector become magnetized and create an additional magnetic field that is superimposed on the original field of the MR scanner. Even after linear shimming, the field homogeneity of the MR scanner remains disrupted by the detector. The authors characterize the field due to the detector with the field of two magnetic dipoles and further show that two sets of permanent magnets (NdFeB) can withstand the main magnetic field and compensate for the nonlinear components of the additional field. The ideal number of magnets and their locations are calculated based on a field map measured with the detector in place. Experimental results demonstrate great promise for this technique, which may be useful in many settings where devices with magnetic components need to be placed inside or close to an MR scanner.

  4. A hybrid liquid chromatography-mass spectrometry strategy in a forensic laboratory for opioid, cocaine and amphetamine classes in human urine using a hybrid linear ion trap-triple quadrupole mass spectrometer.

    Science.gov (United States)

    Dowling, Geraldine; Regan, Liam; Tierney, Julie; Nangle, Michael

    2010-10-29

    A rapid method has been developed to analyse morphine, codeine, morphine-3-glucuronide, 6-monoacetylmorphine, cocaine, benzoylegonine, buprenorphine, dihydrocodeine, cocaethylene, 3,4-methylenedioxyamphetamine, ketamine, 3,4-methylenedioxymethamphetamine, pseudoephedrine, lignocaine, benzylpiperazine, methamphetamine, amphetamine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine and methadone in human urine. Urine samples were diluted with methanol:water (1:1, v/v) and sample aliquots were analysed by hybrid linear ion trap-triple quadrupole mass spectrometry with a runtime of 12.5 min. Multiple reaction monitoring (MRM) as survey scan and an enhanced product ion (EPI) scan as dependent scan were performed in an information-dependent acquisition (IDA) experiment. Finally, drug identification and confirmation was carried out by library search with a developed in-house MS/MS library based on EPI spectra at a collision energy spread of 35±15 in positive mode and MRM ratios. The method was validated in urine, according to the criteria defined in Commission Decision 2002/657/EC. At least two MRM transitions for each substance were monitored in addition to EPI spectra and deuterated analytes were used as internal standards for quantitation. The reporting level was 0.05 μg mL(-1) for the range of analytes tested. The regression coefficients (r(2)) for the calibration curves (0-4 μg mL(-1)) in the study were ≥0.98. The method proved to be simple and time efficient and was implemented as an analytical strategy for the illicit drug monitoring of opioids, cocaines and amphetamines in criminal samples from crime offenders, abusers or victims in the Republic of Ireland. To the best of our knowledge there are no hybrid LC-MS applications using MRM mode and product ion spectra in the linear ion trap mode for opioids, cocaines or amphetamines with validation data in urine.

  5. Effect of mobile phase additives on qualitative and quantitative analysis of ginsenosides by liquid chromatography hybrid quadrupole-time of flight mass spectrometry.

    Science.gov (United States)

    Liang, Yan; Guan, Tianye; Zhou, Yuanyuan; Liu, Yanna; Xing, Lu; Zheng, Xiao; Dai, Chen; Du, Ping; Rao, Tai; Zhou, Lijun; Yu, Xiaoyi; Hao, Kun; Xie, Lin; Wang, Guangji

    2013-07-05

    This study was to systematically investigate the effect of mobile phase additives, including ammonia water, formic acid, acetic acid, ammonium chloride and water (as a control), on qualitative and quantitative analysis of fifteen representative ginsenosides based on liquid chromatography hybrid quadrupole-time of flight mass spectrometry (LC-Q-TOF/MS). To evaluate the influence of mobile phase additives on qualitative performance, the quality of the negative mode MS/MS spectra of ginsenosides produced by online LC-Q-TOF/MS analyses, particularly the numbers and intensities of fragment ions, were compared under different adduct ion states, and found to be strongly affected by the mobile phase additives. When 0.02% acetic acid was added in the mobile phase, the deprotonated ginsenosides ions produced the most abundant product ions, while almost no product ion was observed for the chlorinated ginsenoside ions when 0.1mM ammonium chloride was used as the mobile phase additive. On the other hand, sensitivity, linear range and precision were adopted to investigate the quantitative performance affected by different mobile phase additives. Validation results of the LC-Q-TOF/MS-based quantitative performance for ginsenosides showed that ammonium chloride not only provided the highest sensitivity for all the target analytes, but also dramatically improved the linear ranges, the intra-day and inter-day precisions comparing to the results obtained using other mobile phase additives. Importantly, the validated method, using 0.1mM ammonium chloride as the mobile phase additive, was successfully applied to the quantitative analysis of ginsenosides in rat plasma after intragastric administration of Ginsenoside Extract at 200mg/kg. In conclusion, 0.02% acetic acid was deemed to be the most suitable mobile phase additive for qualitative analysis of ginsenosides, and 0.1mM ammonium chloride in mobile phase could lead to the best quantitative performance. Our results reveal that

  6. Fermilab Tevatron quadrupoles

    Energy Technology Data Exchange (ETDEWEB)

    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. Investigation of a Co-Axial Dual-Mechanical Ports Flux-Switching Permanent Magnet Machine for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Wei Hua

    2015-12-01

    Full Text Available In this paper, a co-axial dual-mechanical ports flux-switching permanent magnet (CADMP-FSPM machine for hybrid electric vehicles (HEVs is proposed and investigated, which is comprised of two conventional co-axial FSPM machines, namely one high-speed inner rotor machine and one low-speed outer rotor machine and a non-magnetic ring sandwiched in between. Firstly, the topology and operation principle of the CADMP-FSPM machine are introduced; secondly, the control system of the proposed electronically-controlled continuously-variable transmission (E-CVT system is given; thirdly, the key design specifications of the CADMP-FSPM machine are determined based on a conventional dual-mechanical ports (DMP machine with a wound inner rotor. Fourthly, the performances of the CADMP-FSPM machine and the normal DMP machine under the same overall volume are compared, and the results indicate that the CADMP-FSPM machine has advantages over the conventional DMP machine in the elimination of brushes and slip rings, improved thermal dissipation conditions for the inner rotor, direct-driven operation, more flexible modes, lower cogging torque and torque ripple, lower total harmonic distortion (THD values of phase PM flux linkage and phase electro-motive force (EMF, higher torque output capability and is suitable for the E-CVT systems. Finally, the pros and cons of the CADMP-FSPM machine are highlighted. This paper lays a theoretical foundation for further research on CADMP-FSPM machines used for HEVs.

  8. General unknown screening in hair by liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS).

    Science.gov (United States)

    Broecker, Sebastian; Herre, Sieglinde; Pragst, Fritz

    2012-05-10

    The retrospective investigation of the exposure to toxic substances by general unknown screening of hair is still a difficult task because of the large number of possible poisons, the low sample amount and the difficult sample matrix. In this study the use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was tested as a promising technique for this purpose. In the optimized procedure, 20mg hair were decontaminated with water and acetone and two times extracted by 18h incubation with 0.5ml of a mixture of methanol/acetonitrile/H(2)O/ammonium formate at 37°C. A mixture of deuterated standards from different drug groups was added for quantification and method control. The united extracts were evaporated to a residue of 0.5ml and 5μl were injected without clean-up for LC-QTOF-MS measurement (instrument Agilent 6530) with positive electrospray ionization and in data dependent acquisition mode. For peak identification the accurate mass data base and spectral library of the authors was used which contains accurate mass CID spectra of more than 2500 and theoretically calculated accurate mass data of more than 7500 toxicologically relevant substances. Validation at the example of 24 illegal drugs, their metabolites and benzodiazepines resulted in limits of detection of 0.003-0.015ng/mg, and limits of quantification of 0.006-0.021ng/mg with good accuracy and intra- and interday reproducibility. The matrix effect by ion suppression/enhancement was 72-107% for basic drugs and 42-75% for benzodiazepines. Yields of the hair extraction above 90% were determined for 59 drugs or metabolites. The method was applied to hair samples from 30 drug fatalities and from 60 death cases with known therapeutic drug intake at life time. Altogether 212 substances were identified with a frequency per drug of 1-40 (mean 4.2) and per case of 2-33 (mean 10.2), between them 35 illegal drug related substances and 154 therapeutic drugs. Comparison with the

  9. P202-S Expanding the Capabilities of Peptide MRM-Based Assays in Plasma Using a Hybrid Triple-Quadrupole Linear Ion-Trap Mass Spectrometer

    OpenAIRE

    Hunter, C.

    2007-01-01

    As the study of protein biomarkers increases in importance, technical limitations to the detection of low-abundance proteins and high-throughput, high-precision quantitation remain to be overcome. The complexity and dynamic range of the plasma proteome makes the task of specific, quantitative detection even more challenging. Multiple reaction monitoring (MRM) capabilities of triple quadrupole MS systems have been explored as solutions to this challenge due to their well-known sensitivity and ...

  10. Non-target screening of Allura Red AC photodegradation products in a beverage through ultra high performance liquid chromatography coupled with hybrid triple quadrupole/linear ion trap mass spectrometry.

    Science.gov (United States)

    Gosetti, Fabio; Chiuminatto, Ugo; Mazzucco, Eleonora; Calabrese, Giorgio; Gennaro, Maria Carla; Marengo, Emilio

    2013-01-15

    The study deals with the identification of the degradation products formed by simulated sunlight photoirradiation in a commercial beverage that contains Allura Red AC dye. An UHPLC-MS/MS method, that makes use of hybrid triple quadrupole/linear ion trap, was developed. In the identification step the software tool information dependent acquisition (IDA) was used to automatically obtain information about the species present and to build a multiple reaction monitoring (MRM) method with the MS/MS fragmentation pattern of the species considered. The results indicate that the identified degradation products are formed from side-reactions and/or interactions among the dye and other ingredients present in the beverage (ascorbic acid, citric acid, sucrose, aromas, strawberry juice, and extract of chamomile flowers). The presence of aromatic amine or amide functionalities in the chemical structures proposed for the degradation products might suggest potential hazards to consumer health.

  11. Quantitative analysis of low-abundance serological proteins with peptide affinity-based enrichment and pseudo-multiple reaction monitoring by hybrid quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Kim, Kwang Hoe; Ahn, Yeong Hee; Ji, Eun Sun; Lee, Ju Yeon; Kim, Jin Young; An, Hyun Joo; Yoo, Jong Shin

    2015-07-02

    Multiple reaction monitoring (MRM) is commonly used for the quantitative analysis of proteins during mass pectrometry (MS), and has excellent specificity and sensitivity for an analyte in a complex sample. In this study, a pseudo-MRM method for the quantitative analysis of low-abundance serological proteins was developed using hybrid quadrupole time-of-flight (hybrid Q-TOF) MS and peptide affinity-based enrichment. First, a pseudo-MRM-based analysis using hybrid Q-TOF MS was performed for synthetic peptides selected as targets and spiked into tryptic digests of human serum. By integrating multiple transition signals corresponding to fragment ions in the full scan MS/MS spectrum of a precursor ion of the target peptide, a pseudo-MRM MS analysis of the target peptide showed an increased signal-to-noise (S/N) ratio and sensitivity, as well as an improved reproducibility. The pseudo-MRM method was then used for the quantitative analysis of the tryptic peptides of two low-abundance serological proteins, tissue inhibitor of metalloproteinase 1 (TIMP1) and tissue-type protein tyrosine phosphatase kappa (PTPκ), which were prepared with peptide affinity-based enrichment from human serum. Finally, this method was used to detect femtomolar amounts of target peptides derived from TIMP1 and PTPκ, with good coefficients of variation (CV 2.7% and 9.8%, respectively), using a few microliters of human serum from colorectal cancer patients. The results suggest that pseudo-MRM using hybrid Q-TOF MS, combined with peptide affinity-based enrichment, could become a promising alternative for the quantitative analysis of low-abundance target proteins of interest in complex serum samples that avoids protein depletion.

  12. Efficient Pulsed Quadrupole

    CERN Document Server

    Petzenhauser, I.; Spiller, P.; Tenholt, C.

    2016-01-01

    In order to raise the focusing gradient in case of bunched beam lines, a pulsed quadrupole was designed. The transfer channels between synchrotrons as well as the final focusing for the target line are possible applications. The quadrupole is running in a pulsed mode, which means an immense saving of energy by avoiding standby operation. Still the high gradients demand high currents. Hence a circuit had to be developed which is able to recover a significant amount of the pulsing energy for following shots. The basic design of the electrical circuit of the quadrupole is introduced. Furthermore more energy efficient circuits are presented and the limits of adaptability are considered.

  13. Superconducting magnetic quadrupole

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. SPS Quadrupole Magnets

    CERN Multimedia

    1974-01-01

    A stack of SPS Quadrupole Magnets ready for installation in the tunnel. The SPS uses a total of 216 laminated normal conducting lattice quadrupoles with a length of 3.13 m for the core, 3.3 m overall. The F and D quads. have identical characteristics: inscribed circle radius 44 mm, core height and width 800 mm, maximum gradient 20 Tesla/m.

  15. Electromagnetic Comparison of 3-, 5- and 7-phases Permanent-Magnet Synchronous Machines : Mild Hybrid Traction Application

    Directory of Open Access Journals (Sweden)

    D. Ouamara

    2016-09-01

    Full Text Available Authors compare the electromagnetic performances of three multi-phases permanent-magnet (PM synchronous machines (PMSM for Mild Hybridtraction application. This comparison was made using two-dimensional (2-D numerical simulations in transient magnetic with eddy-current reaction field in the PMs. The best machine was determined using an energetic analysis (i.e., losses, torque and efficiency according specifications. In this study, the non-overlapping winding with double layer (i.e. all teeth wound type was used. The winding synthesis is based on the "Star of slots" method as well as the Fourier series decomposition of the magnetomotive force (MMF.

  16. Confirmation of pinnatoxins and spirolides in shellfish and passive samplers from Catalonia (Spain) by liquid chromatography coupled with triple quadrupole and high-resolution hybrid tandem mass spectrometry.

    Science.gov (United States)

    García-Altares, María; Casanova, Alexis; Bane, Vaishali; Diogène, Jorge; Furey, Ambrose; de la Iglesia, Pablo

    2014-06-01

    Cyclic imines are lipophilic marine toxins that bioaccumulate in seafood. Their structure comprises a cyclic-imino moiety, responsible for acute neurotoxicity in mice. Cyclic imines have not been linked yet to human poisonings and are not regulated in Europe, although the European Food Safety Authority requires more data to perform a conclusive risk assessment for consumers. This work presents the first detection of pinnatoxin G (PnTX-G) in Spain and 13-desmethyl spirolide C (SPX-1) in shellfish from Catalonia (Spain, NW Mediterranean Sea). Cyclic imines were found at low concentrations (2 to 60 µg/kg) in 13 samples of mussels and oysters (22 samples analyzed). Pinnatoxin G has been also detected in 17 seawater samples (out of 34) using solid phase adsorption toxin tracking devices (0.3 to 0.9 µg/kg-resin). Pinnatoxin G and SPX-1 were confirmed with both low and high resolution (<2 ppm) mass spectrometry by comparison of the response with that from reference standards. For other analogs without reference standards, we applied a strategy combining low resolution MS with a triple quadrupole mass analyzer for a fast and reliable screening, and high resolution MS LTQ Orbitrap® for unambiguous confirmation. The advantages and limitations of using high resolution MS without reference standards were discussed.

  17. Study of the Advantages of Internal Permanent Magnet Drive Motor with Selectable Windings for Hybrid-Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Otaduy, P.J.; Hsu, J.S.; Adams, D.J.

    2007-11-30

    This report describes research performed on the viability of changing the effectively active number of turns in the stator windings of an internal permanent magnet (IPM) electric motor to strengthen or weaken the magnetic fields in order to optimize the motor's performance at specific operating speeds and loads. Analytical and simulation studies have been complemented with research on switching mechanisms to accomplish the task. The simulation studies conducted examine the power and energy demands on a vehicle following a series of standard driving cycles and the impact on the efficiency and battery size of an electrically propelled vehicle when it uses an IPM motor with turn-switching capabilities. Both full driving cycle electric propulsion and propulsion limited starting from zero to a set speed have been investigated.

  18. Towards a universal LC-MS screening procedure - can an LIT LC-MS(n) screening approach and reference library be used on a quadrupole-LIT hybrid instrument?

    Science.gov (United States)

    Wissenbach, Dirk K; Meyer, Markus R; Weber, Armin A; Remane, Daniela; Ewald, Andreas H; Peters, Frank T; Maurer, Hans H

    2012-01-01

    In contrast to libraries with highly reproducible gas chromatography electron ionization mass spectra, current liquid chromatography (LC-MS) libraries are limited to specific instrument types. Therefore, the aim of the study was to prove whether a recently developed linear ion trap (LIT) LC-MS(n) screening approach and reference library can be transferred to an LC-MS/MS system with a quadrupole-LIT hybrid mass analyzer using SmileMS, a sophisticated search algorithm. The LIT reference library was built with MS² and MS³ wideband spectra recorded on a ThermoFisher LXQ LIT with electrospray ionization in positive mode and full-scan data-dependent acquisition (DDA). Collision parameter optimizations, including different scan types and energies, were performed on an Applied Biosystems QTRAP 4000 system using electrospray ionization in positive mode and full-scan DDA. Modified library sets were generated to improve the detection of a compound by the used search algorithm. Additionally, 100 authentic human urine samples were screened by both systems for proof of applicability. In the applicability study, 533 compounds were detected by the LXQ and 477 by the QTRAP system using enhanced product ion scan and a modified database. The presented data showed that the LIT screening approach and reference library could be used successfully on a QTRAP instrument with some limitations. These should be overcome by further optimizations regarding DDA settings for better sensitivity and further library modifications to reduce spectra mismatches.

  19. A novel approach for identification of biologically active phenolic compounds in complex matrices using hybrid quadrupole-orbitrap mass spectrometer: A promising tool for testing antimicrobial activity of hops.

    Science.gov (United States)

    Dušek, Martin; Jandovská, Vladimíra; Čermák, Pavel; Mikyška, Alexandr; Olšovská, Jana

    2016-08-15

    The phenolic compounds, secondary metabolites of hops represent a large family of compounds that could be subsequently divided into smaller groups based on the similarities between their chemical structures. The antibacterial, antifungal and antiviral properties of hops are well known, but there is a lack of information about antimicrobial activities of individual hop compounds. This study was carried out with an objective to identify compounds present in hops that have potential antibacterial activity. In the first stage of experiment, the active compounds with potential anti-microbial activity had to be extracted from hop cones. Therefore, minced hop cones were applied on solid growth medium inoculated with Staphylococcus aureus. The active substances that migrated into the medium created an inhibition zone. In the second stage of experiment, the inhibition zones were cut out from Petri dishes, active compounds were extracted from these zones and consequently analyzed using LC-HRMS. These complex assays were developed and optimized. The data were acquired by using a quadrupole-orbitrap hybrid mass spectrometer by targeted-MS2 experiment in both ionization modes. The MS method has been developed as a screening method with a subsequent fragmentation of compound of interest on the base of inclusion mass list. The unknown compounds extracted from inhibition zones have been identified either by searching against a database or their structure has been elucidated on the basis of their fragmentation spectra. On the basis of this experiment the list of active compounds with potential anti-microbial activities was enhanced.

  20. Analytical strategy based on the combination of gas chromatography coupled to time-of-flight and hybrid quadrupole time-of-flight mass analyzers for non-target analysis in food packaging.

    Science.gov (United States)

    Cherta, L; Portolés, T; Pitarch, E; Beltran, J; López, F J; Calatayud, C; Company, B; Hernández, F

    2015-12-01

    The potential of an advanced analytical strategy based on the use of gas chromatography (GC) coupled to high resolution mass spectrometry (HRMS) with two different analyzers and ionization sources has been investigated and applied to the non-target analysis of food packaging contaminants. Initially, the approach based on GC-time-of-flight (TOF) MS with electron ionization (EI) source allowed performing a library search and mass accurate measurements of selected ions. Then, a second analysis was performed using hybrid quadrupole (Q) TOF MS with an atmospheric pressure chemical ionization (APCI) source in order to search for the molecular ion or the protonated molecule and study the fragmentation behavior. This analytical strategy was applied to the analysis of four polypropylene/ethylene vinyl alcohol/polypropylene (PP/EVOH/PP) multilayer trays and one PP/Al foil/PP film, each one subjected to migration assays with the food simulants isooctane and Tenax®, in order to investigate its potential on the determination of migrant substances.

  1. ISR "Terwilliger" Quadrupole

    CERN Multimedia

    1983-01-01

    There were 48 of these Quadrupoles in the ISR. They were distributed around the rings according to the so-called Terwilliger scheme. Their aperture was 184 mm, their core length 300 mm, their gradient 5 T/m. Due to their small length as compared to the aperture, the end fringe field errors had to be compensated by suitably shaping the poles.

  2. ISR Superconducting Quadrupoles

    CERN Multimedia

    1977-01-01

    Michel Bouvier is preparing for curing the 6-pole superconducting windings inbedded in the cylindrical wall separating liquid helium from vacuum in the quadrupole aperture. The heat for curing the epoxy glue was provided by a ramp of infrared lamps which can be seen above the slowly rotating cylinder. See also 7703512X, 7702690X.

  3. A Fuzzy Logic Global Power Management Strategy for Hybrid Electric Vehicles Based on a Permanent Magnet Electric Variable Transmission

    Directory of Open Access Journals (Sweden)

    Shumei Cui

    2012-04-01

    Full Text Available The major contribution of this paper is to propose a Fuzzy Logic Global Power Management Strategy for Hybrid Electric Vehicles (HEVs that are driven by the PM-EVT (PM machine—Electric Variable Transmission powertrain, such that the PM-EVT will have superior advantages over other types of powertrains, including the current Toyota Prius powertrain for series-parallel HEVs. This has been investigated throughout three aspects. The first is the optimum power splitting between the Internal Combustion Engine (ICE and the PM-EVT. The second is maximizing the vehicle’s energy capture during the braking process. Finally, sustaining the State of Charge (SOC of the battery is adopted by a robust ON/OFF controller of the ICE. These goals have been accomplished by developing three fuzzy logic (FL controllers. The FL controllers are designed based on the state of charge of the battery, vehicle’s velocity, traction torque, and the vehicle’s requested power. The integration of the studied system is accomplished via the Energetic Macroscopic Representation (EMR simulation model strategy based on the software Matlab/Simulink. The PM-EVT based HEV system with the proposed power management strategy is validated by comparing to the Toyota Prius HEV. The vehicle’s performances have been analyzed throughout a combined long-trip driving cycle that represents the normal and the worst operating conditions. The simulation results show that global control system is effective to control the engine’s operating points within the highest efficiency region, exploiting of EVT machines for capturing maximum braking energy, as well as to sustain the SOC of the battery while satisfy the drive ability. The proposed control strategy for the studied HEVs sounds interesting and feasible as supported by a large amount of simulation results.

  4. Unraveling the in vitro and in vivo metabolism of diacetoxyscirpenol in various animal species and human using ultrahigh-performance liquid chromatography-quadrupole/time-of-flight hybrid mass spectrometry.

    Science.gov (United States)

    Yang, Shupeng; De Boevre, Marthe; Zhang, Huiyan; De Ruyck, Karl; Sun, Feifei; Wang, Zhanhui; Cao, Xingyuan; Shen, Jianzhong; De Saeger, Sarah; Zhang, Suxia

    2015-11-01

    Diacetoxyscirpenol (DAS), a Fusarium mycotoxin belonging to the trichothecene type A mycotoxins, is able to contaminate food and feed worldwide. Only limited information is available regarding the metabolism of DAS. The present study used ultrahigh-performance liquid chromatography-quadrupole/time-of-flight hybrid mass spectrometry (UHPLC-Q/TOF) to investigate the in vitro phase I and II metabolism of DAS by rat, chicken, swine, goat, cow, and human liver microsomes. An extensive metabolization profile of DAS has been observed. A total of seven phase I and three phase II metabolites of DAS were detected. Among the identified molecules, four phase I metabolites (8β-hydroxy-DAS, neosolaniol, 7-hydroxy-DAS, and its epimer) and two phase II metabolites (4-deacetyl-DAS-3-glucuronic acid and 4-deacetyl-DAS-4-glucuronic acid) were identified for the first time. These results indicate that the major metabolic pathways of DAS in vitro were hydrolyzation (M1-M3), hydroxylation (M4-M7), and conjugation (M8-M10). Qualitative differences in phase I and II metabolic profiles of DAS between the five animal species and human were observed. 4-Deacetyl-DAS was the primary metabolite from liver microsomes of all species, especially human. The in vivo metabolism of DAS in rats and chickens after oral administration of DAS was also investigated and compared. The major metabolites for rats and chickens were 4-deacetyl-DAS and 7-hydroxy-DAS. These results will help to gain a more detailed insight into the metabolism and toxicity of DAS among different animal species and human. Graphical Abstract The metabolism of diacetoxyscirpenol in farm animals and human.

  5. Conceptual design of a quadrupole magnet for eRHIC

    Energy Technology Data Exchange (ETDEWEB)

    Witte, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    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.

  6. Quadrupole collectivity with isospin

    Energy Technology Data Exchange (ETDEWEB)

    Ginocchio, J.N.; Leviatan, A. (Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States) Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel))

    1994-10-03

    We study intrinsic aspects of quadrupole collectivity with conserved isospin in the framework of the interacting boson model (IBM-3) of nuclei. A geometric visualization is achieved by means of a novel type of intrinsic states which are deformed in angular momentum yet have well defined isospin. The energy surface of the general IBM-3 Hamiltonian is derived and normal modes are identified for prolate deformations.

  7. AA quadrupole magnet

    CERN Multimedia

    1980-01-01

    Focusing magnet used for the AA (antiproton accumulator).Making an antiproton beam took a lot of time and effort. Firstly, protons were accelerated to an energy of 26 GeV in the PS and ejected onto a metal target. From the spray of emerging particles, a magnetic horn picked out 3.6 GeV antiprotons for injection into the AA through a wide-aperture focusing quadrupole magnet. For a million protons hitting the target, just one antiproton was captured, 'cooled' and accumulated. It took 3 days to make a beam of 3 x 10^11 - three hundred thousand million - antiprotons. About focusing magnets (quadrupoles): Quadrupole magnets are needed to focus the particle beams and squeeze them so that more particles collide when the beams cross. Particle beams are stored for about 10 hours in the LHC. During this time, the particles make four hundred million revolutions around the machine, travelling a distance equivalent to the diameter of the solar system.

  8. The first LHC insertion quadrupole

    CERN Multimedia

    2004-01-01

    An important milestone was reached in December 2003 at the CERN Magnet Assembly Facility. The team from the Accelerator Technology - Magnet and Electrical Systems group, AT-MEL, completed the first special superconducting quadrupole for the LHC insertions which house the experiments and major collider systems. The magnet is 8 metres long and contains two matching quadrupole magnets and an orbit corrector, a dipole magnet, used to correct errors in quadrupole alignment. All were tested in liquid helium and reached the ultimate performance criteria required for the LHC. After insertion in the cryostat, the superconducting magnet will be installed as the Q9 quadrupole in sector 7-8, the first sector of the LHC to be put in place in 2004. Members of the quadrupole team, from the AT-MEL group, gathered around the Q9 quadrupole at its inauguration on 12 December 2003 in building 181.

  9. High-throughput shotgun lipidomics by quadrupole time-of-flight mass spectrometry

    DEFF Research Database (Denmark)

    Ståhlman, Marcus; Ejsing, Christer S.; Tarasov, Kirill;

    2009-01-01

    Technological advances in mass spectrometry and meticulous method development have produced several shotgun lipidomic approaches capable of characterizing lipid species by direct analysis of total lipid extracts. Shotgun lipidomics by hybrid quadrupole time-of-flight mass spectrometry allows...

  10. MQXFS1 Quadrupole Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosio, Giorgio [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); et al.

    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.

  11. Combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with photodiode array detector (HPLC-DAD) in systematic toxicological analysis.

    Science.gov (United States)

    Broecker, Sebastian; Pragst, Fritz; Bakdash, Abdulsallam; Herre, Sieglinde; Tsokos, Michael

    2011-10-10

    Time of flight mass spectrometry provides new possibilities of substance identification by determination of the molecular formula from accurate molecular mass and isotope pattern. However, the huge number of possible isomers requires additional evidence. As a suitable way for routine performance of systematic toxicological analysis, a method for combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with diode array detector (HPLC-DAD) was developed and applied to blood samples from 77 death cases. The blood samples were prepared by extraction with CH(2)Cl(2) and by protein precipitation with acetonitrile (1:4 (v/v)). The evaporated extracts were reconstituted in 35% acetonitril/0.1% formic acid/H(2)O and aliquots were injected for analysis by LC-QTOF-MS (Agilent 6530) and HPLC-DAD (Agilent 1200). A valve switching system enabled simultaneous operation of both separated chromatographic lines under their respective optimal conditions using the same autosampler. The ESI-QTOF-MS instrument was run in data dependent acquisition mode with switching between MS and MS/MS (cycle time 1.1s) and measuring the full mass spectra and the collision induced dissociation (CID) fragment spectra of all essential [M+H](+) ions. Libraries of accurate mass CID spectra (~2500 substances) and of DAD-UV spectra (~3300 substances) of the authors were used for substance identification. The application of this procedure is demonstrated in detail at four examples with multiple drug intake or administration. In the 77 cases altogether 198 substances were identified (87 by DAD and 195 by QTOF-MS) with a frequency between 1 and 20. In practical application, the sample preparation proved to be suitable for both techniques and for a wide variety of substances with different polarity. The automatic performance of the measurements was efficient and robust. Mutual confirmation, decrease of false positive and

  12. CLIC Quadrupole Module final report

    CERN Document Server

    Artoos, K; Mainaud-Durand, H

    2013-01-01

    Future Linear colliders will need particle beam sizes in the nanometre range. The beam also needs to be stable all along the beam line. The CLIC Main Beam Quadrupole (MBQ) module has been defined and studied. It is meant as a test stand for stabilisation and pre-alignment with a MB Quadrupole. The main topic that has been tackled concerns the Quadrupole magnet stabilisation to 1nm at 1Hz. This is needed to obtain the desired CLIC luminosity of 2.1034 cm-2m-1. The deliverable was demonstrated by procuring a MBQ and by stabilising a powered and cooled CLIC MBQ quadrupole. In addition, the stabilisation system has to be compatible with the pre-alignment procedures. Pre-alignment movement resolution has been demonstrated to 1m. The last step is the combined test of stability with a quadrupole on a CLIC Module with the pre-alignment.

  13. Considerations for a QD0 with Hybrid Technology in ILC

    CERN Document Server

    Modena, M; Garcia, H; Gatignon, L; Tomas, R

    2014-01-01

    The baseline design of the QD0 magnet for ILC, the International Linear Collider, is a very compact superconducting quadrupole (coil-dominated magnet). A prototype of this quadrupole is under construction at Brookhaven National Laboratory (USA). In CLIC, the Compact Linear Collider under study at CERN, we are studying a different conceptual solution for the QD0. This is due to two main reasons: all the magnets of the Beam Delivery System will need to be stabilized in the nano-meter range and extremely tight alignment tolerances are required. The proposed solution, now baseline for CLIC, is a room temperature hybrid quadrupole based on resistive coils and permanent magnet blocks (iron-dominated magnet). In this paper we present a conceptual design for a hybrid solution studied and adapted also to the ILC project. A super-ferric solution (superconducting coils with warm iron poles) is proposed to make the cross section compatible with the layout of the experiments. This design matches the compactness requiremen...

  14. Quadrupole Induced Resonant Particle Transport

    Science.gov (United States)

    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.)

  15. Correlation of experimental data and three-dimensional finite element modeling of a spinning quadrupole

    Science.gov (United States)

    Lorimer, W. L.; Lieu, D. K.; Hull, J. R.; Mulcahy, T. M.; Rossing, T. D.

    A permanent magnet quadrupole spinning over an aluminum disk was constructed, and drag torque was measured for various speeds and gap sizes. The experiment was modeled using a three-dimensional finite element program. Experimental and analytical results were compared, and the effect of magnet polarity was determined.

  16. Improvement of the propulsion force for HTSC-permanent magnet hybrid magnetically levitated carrying system by using the pinned flux of HTSC

    Science.gov (United States)

    Ikeda, M.; Sasaki, R.; Ueno, T.; Ohashi, S.

    Magnetically levitated carrying system has been developed. In this system, pinning force of high temperature bulk superconductor (HTSC) is used for the levitation and guidance. The magnetic rail is set on the ground, and flux from the magnetic rail is pinned by HTSCs. To increase levitation force, repulsive force of the permanent magnet is used. For the propulsion system, electromagnets are installed on the surface of the magnetic rail. Improvement of the propulsion force is studied. In the previous system, only flux of the permanent magnet of the carrier is used for propulsion. To increase propulsion force, that of the HTSC of the carrier is also used. Using this excitation method, the propulsion force is improved even though total number of the excited coil is the same.

  17. Nuclear Quadrupole Moments and Nuclear Shell Structure

    Science.gov (United States)

    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.

  18. Accretion disks around a mass with quadrupole

    CERN Document Server

    Abishev, Medeu; Quevedo, Hernando; Toktarbay, Saken

    2015-01-01

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

  19. Accretion disks around a mass with quadrupole

    Science.gov (United States)

    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.

  20. LCLS Undulator Quadrupole Fiducialization Plan

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Essure Permanent Birth Control

    Science.gov (United States)

    ... Prosthetics Essure Permanent Birth Control Essure Permanent Birth Control Share Tweet Linkedin Pin it More sharing options ... System Essure is a a permanently implanted birth control device for women (female sterilization). Implantation of Essure ...

  2. Fiducialization of the small-aperture quadrupoles based on the vibrating wire method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Baichuan, E-mail: wangbaichuan@nint.ac.cn [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect (Northwest Institute of Nuclear Technology), Xi' an 710024 (China); Tsinghua University, Beijing 100084 (China); Zheng, Shuxin, E-mail: zhengsx@tsinghua.edu.cn [Tsinghua University, Beijing 100084 (China); Wu, Lin; Du, Changtong; Xing, Qingzi [Tsinghua University, Beijing 100084 (China); Wang, Zhongming; Qiu, Mengtong [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect (Northwest Institute of Nuclear Technology), Xi' an 710024 (China); Wang, Xuewu [Tsinghua University, Beijing 100084 (China)

    2016-03-11

    A fiducialization method based on vibrating wire is described dedicated to the problem of locating the magnetic center relative to external fiducials for the small-aperture quadrupoles. The advantage of this method is that the measurement of the wire position, which may be the main error source, is no longer needed. The position of the magnetic center can be directly obtained by measuring the position shift of the magnet fiducials. This method has been validated on small Permanent Magnet Quadrupoles (PMQs). Experiments have confirmed its feasibility of measuring PMQs with good repeatability of about 10 μm, and shown its high sensitivity as well as convenience.

  3. Research on Hybrid Vehicle Drivetrain

    Science.gov (United States)

    Xie, Zhongzhi

    Hybrid cars as a solution to energy saving, emission reduction measures, have received widespread attention. Motor drive system as an important part of the hybrid vehicles as an important object of study. Based on the hybrid electric vehicle powertrain control system for permanent magnet synchronous motor as the object of study. Can be applied to hybrid car compares the characteristics of traction motors, chose permanent magnet synchronous Motors as drive motors for hybrid vehicles. Building applications in hybrid cars in MATLAB/Simulink simulation model of permanent-magnet synchronous motor speed control system and analysis of simulation results.

  4. 液相色谱/四级杆飞行时间质谱分析烟酸芽胞杆菌发酵产物苯乳酸%Analysis on phenyllactic acid fromBacillus niacinibased on liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    朱育菁; 刘波; 郑梅霞; 陈峥

    2015-01-01

    ABSTRACT:Objective To analyze and test on active substance fromBacillus niacini FJAT-14202. MethodsExtracellular metabolites ofBacillus niacini FJAT-14202 were analyzed by liquid chromatography- hybrid quadrupole time-of-flight mass spectrometry. Molecular feature extraction(MFE) and database retrieval were applied by Agilent Mass Hunter software, for the information overall metabolites.Results Totally 811 compounds were detected, and 165 of them were identified by library searching of Metlin database. The match score of phenyllactic acid was 96.52 and itsrelative content was 5.31%. The retention time of phenyllactic acid was about 2.1057 min, and its accurate mass was 166.0552.Conclusion The results provide the theory basis for development and utilization of phenyllactic acid fromBacillus niacini.%目的:对烟酸芽胞杆菌Bacillus niaciniFJAT-14202来源的苯乳酸成分进行分析与检测。方法采用液相色谱/四级杆飞行时间质谱(liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry)分析烟酸芽胞杆菌FJAT-14202发酵液中胞外代谢物的成分。利用 MassHunter软件,对原始数据进行分子特征提取,通过Metlin代谢物质谱数据库检索比对获得代谢物的信息。结果在烟酸芽胞杆菌FJAT-14202发酵液中检测到811种代谢物,通过Metlin谱库搜索获得初步鉴定的有165种。其中,发现了具有生物活性的物质苯乳酸,其匹配得分达到96.52,占发酵液总代谢物相对含量的5.31%,保留时间分别为2.1057 min,精确质量数为166.0552。结论苯乳酸的发现为烟酸芽胞杆菌的开发与利用提供理论依据。

  5. Cool Down Analysis of a Cryocooler Based Quadrupole Magnet Cryostat

    Science.gov (United States)

    Choudhury, A.; Kar, S.; Chacko, J.; Kumar, M.; Babu, S.; Sahu, S.; Kumar, R.; Antony, J.; Datta, T. S.

    A superconducting quadrupole doublet magnet with cold superferric iron cover for the Hybrid Recoil Mass Analyzer (HYRA) beam line has been commissioned. The total cold mass of the helium vessel with iron yoke and pole is 2 ton. A set of two Sumitomo cryocoolers take care of various heat loads to the cryostat. The first successful cool down of the cryostat has been completed recently, magnets have been powered and magnetic field profiling has been done inside theroom temperature beam tube. This paper will highlight the cryostat details along with the cool down and operational test results obtained from the first cool down.

  6. MQXFS1 Quadrupole Fabrication Report

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosio, G.; et al.

    2017-07-16

    This report presents the fabrication and QC data of MQXFS1, the first short model of the low-beta quadrupoles (MQXF) for the LHC High Luminosity Upgrade. It describes the conductor, the coils, and the structure that make the MQXFS1 magnet. Qualification tests and non-conformities are also presented and discussed. The fabrication of MQXFS1 was started before the finalization of conductor and coil design for MQXF magnets. Two strand design were used (RRP 108/127 and RRP 132/169). Cable and coil cross-sections were “first generation”.

  7. Permanent Magnet System for MRI with Constant Gradient mechanically adjustable in Direction and Strength

    CERN Document Server

    Blümler, Peter

    2015-01-01

    A design for a permanent magnet system is proposed that generates spatially homogeneous, constant magnetic field gradients, thus creating conditions suitable for MRI without gradient coils and amplifiers. This is achieved by superimposing a weak Halbach quadrupole on a strong Halbach dipole. Rotation of either the quadrupole or the entire magnet assembly can be used to generate 2D images via filtered back-projection. Additionally, the mutual rotation of two quadrupoles can be used to scale the resulting gradient. If both gradients have identical strength the gradient can even be made to vanish. The concept is demonstrated by analytical considerations and FEM-simulations.

  8. Rapid, high performance method for the determination of vitamin K(1), menaquinone-4 and vitamin K(1) 2,3-epoxide in human serum and plasma using liquid chromatography-hybrid quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Gentili, Alessandra; Cafolla, Arturo; Gasperi, Tecla; Bellante, Simona; Caretti, Fulvia; Curini, Roberta; Fernández, Virginia Pérez

    2014-04-18

    Unlike the other fat-soluble vitamins, vitamin K circulates in the human bloodstream at very low levels because of a low intake in the diet. Mammals have developed an efficient recycling system, known as vitamin K-epoxide cycle, which involve quinone, hydroquinone and epoxide forms of the vitamin. Phylloquinone (K(1)) is the main homologue, while menaquinone-4 (MK-4) is both a member of the vitamin K(2) family and metabolite of K(1) in extra-hepatic tissues. Notwithstanding the recent advances, many aspects of the complex vitamin K physiology still remain to be investigated. Therefore, there is a critical need to develop more reliable analytical methods for determining the vitamin K and its metabolites in biological fluids and tissues. Nevertheless, relatively low concentrations, unavailability of some authentic standards and occurrence of interfering lipids make this a challenging task. The method proposed in the present paper can directly and accurately estimate K(1), K(1) 2,3-epoxide (K(1)O), and MK-4 in human serum and plasma at concentrations in the ng/L-μg/L range, using labelled internal standards and a quadrupole linear ion trap instrument operated in multiple reaction monitoring (MRM) mode. High sensitivity was achieved by removing signal "endogenous suppressors" and making the composition of the non-aqueous mobile phase suitable to support the positive atmospheric pressure chemical ionization of the analytes. An excellent selectivity resulted from the combination of some factors: the MRM acquisition, the adoption of an identification point system, an extraction optimized to remove most of the lipids and a tandem-C18 column-system necessary to separate isobaric interferences from analytes. The method was validated according to the Food and Drug Administration (FDA) guidelines and its accuracy was assessed by analysing 9 samples from the Vitamin K External Quality Assessment Scheme (KEQAS). Its feasibility in evaluating vitamin K status in human serum was

  9. Marxism as permanent revolution

    NARCIS (Netherlands)

    van Ree, E.

    2013-01-01

    This article argues that the 'permanent revolution' represented the dominant element in Karl Marx and Friedrich Engels' political discourse, and that it tended to overrule considerations encapsulated in 'historical materialism'. In Marx and Engels's understanding, permanent revolution did not repres

  10. Marxism as permanent revolution

    NARCIS (Netherlands)

    van Ree, E.

    2013-01-01

    This article argues that the 'permanent revolution' represented the dominant element in Karl Marx and Friedrich Engels' political discourse, and that it tended to overrule considerations encapsulated in 'historical materialism'. In Marx and Engels's understanding, permanent revolution did not

  11. EMS磁悬浮列车的零电流型永磁电磁混合磁铁设计技术研究%Design of Zero-Power Hybrid Magnet with Permanent Magnets and Electromagnets in EMS Maglev Vehicles

    Institute of Scientific and Technical Information of China (English)

    李云钢; 张晓; 程虎; 刘恒坤

    2011-01-01

    针对EMS磁悬浮列车的零电流型永磁电磁混合磁铁,研究其永磁体和电磁线圈结构参数的设计方法.永磁体安装在磁轭部位,其截面积不受磁极面积的限制,研究得出永磁体的厚度与其截面积的约束关系,并给出永磁重量最小化的设计方法.根据最大平衡安匝数要求,研究得出相对于纯电磁铁,混合磁铁的电磁线圈匝数可减半.由于混合磁铁的可控性能低于纯电磁铁,基于可控性要求,给出修正永磁体的结构参数的方法.最后给出一个实例,将1t负载悬浮在8mm间隙内,所需永磁体仅为6.4 kg.%To design the zero-power hybrid magnet with permanent magnets and electromagnets for EMS maglev vehicles, the structural parameters of its permanent magnets and electromagnets were researched on. The permanent magnet was located at die middte of the yoke, which made its sectional area independent from the area of the pole. The restriction between the thickness and the area of the permanent magnet was presented, and the method of designing the permanent magnet with minimum mass was given. According to the requirements of the maximum balance ampere-turn, it was concluded that the ampere-turn of the hybrid magnet can be reduced to half of that of the pure electromagnet. It was shown that the controllability of the hybrid magnet is always weaker than that of the pure electromagnet, and then a revision of the design for the permanent magnet was proposed based on the requirement of the controllability. Finally, a design example of the hybrid magnet was presented with 11 load suspending at 8 mm, and the mass of the permanent magnet was only 6.4 kg.

  12. The radio-frequency quadrupole

    CERN Document Server

    Vretenar, Maurizio

    2013-01-01

    Radio-frequency quadrupole (RFQ) linear accelerators appeared on the accelerator scene in the late 1970s and have since revolutionized the domain of low-energy proton and ion acceleration. The RFQ makes the reliable production of unprecedented ion beam intensities possible within a compact radio-frequency (RF) resonator which concentrates the three main functions of the low-energy linac section: focusing, bunching and accelerating. Its sophisticated electrode structure and strict beam dynamics and RF requirements, however, impose severe constraints on the mechanical and RF layout, making the construction of RFQs particularly challenging. This lecture will introduce the main beam optics, RF and mechanical features of a RFQ emphasizing how these three aspects are interrelated and how they contribute to the final performance of the RFQ.

  13. AA, shims and washers on quadrupole ends

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    Due to the fact that much of the field of the quadrupoles was outside the iron (in particular with the wide quadrupoles) and that thus the fields of quadrupoles and bending magnets interacted, the lattice properties of the AA could not be predicted with the required accuracy. After a first running period in 1980, during which detailed measurements were made with proton test beams, corrections to the quadrupoles were made in 1981, in the form of laminated shims at the ends of the poles, and with steel washers. With the latter ones, further refinements were made in an iterative procedure with measurements on the circulating beam. This eventually resulted, amongst other things, in a very low chromaticity, with the Q-values being constant to within +- 0.001 over the total momentum range of 6 %. Here we see the shims and washers on a narrow qudrupole (QFN, QDN). See also 8103203, 8103204, 8103205, 8103206.

  14. ISR Superconducting Quadrupole in its cryostat

    CERN Multimedia

    1978-01-01

    The picture shows a superconducting quadrupole for the ISR high luminosity (low beta) insertion in its cryostat during final tests before installation in the ISR.The person is W.Burgess. See also photo 7702690X.

  15. Permanent magnet system to guide superparamagnetic particles

    Science.gov (United States)

    Baun, Olga; Blümler, Peter

    2017-10-01

    A new concept of using permanent magnet systems for guiding superparamagnetic nano-particles on arbitrary trajectories over a large volume is proposed. The basic idea is to use one magnet system which provides a strong, homogeneous, dipolar magnetic field to magnetize and orient the particles, and a second constantly graded, quadrupolar field, superimposed on the first, to generate a force on the oriented particles. In this configuration the motion of the particles is driven predominantly by the component of the gradient field which is parallel to the direction of the homogeneous field. As a result, particles are guided with constant force and in a single direction over the entire volume. The direction is simply adjusted by varying the angle between quadrupole and dipole. Since a single gradient is impossible due to Gauß' law, the other gradient component of the quadrupole determines the angular deviation of the force. However, the latter can be neglected if the homogeneous field is stronger than the local contribution of the quadrupole field. A possible realization of this idea is a coaxial arrangement of two Halbach cylinders. A dipole to evenly magnetize and orient the particles, and a quadrupole to generate the force. The local force was calculated analytically for this particular geometry and the directional limits were analyzed and discussed. A simple prototype was constructed to demonstrate the principle in two dimensions on several nano-particles of different size, which were moved along a rough square by manual adjustment of the force angle. The observed velocities of superparamagnetic particles in this prototype were always several orders of magnitude higher than the theoretically expected value. This discrepancy is attributed to the observed formation of long particle chains as a result of their polarization by the homogeneous field. The magnetic moment of such a chain is then the combination of that of its constituents, while its hydrodynamic radius

  16. Rapid determination of 30 bioactive constituents in XueBiJing injection using ultra high performance liquid chromatography-high resolution hybrid quadrupole-orbitrap mass spectrometry coupled with principal component analysis.

    Science.gov (United States)

    Zuo, Lihua; Sun, Zhi; Hu, Yurong; Sun, Ya; Xue, Wenhua; Zhou, Lin; Zhang, Jun; Bao, Xiaoyue; Zhu, Zhenfeng; Suo, Guanglu; Zhang, Xiaojian

    2017-04-15

    Xuebijing injection (XBJ) is a traditional Chinese herbal prescription widely used in the treatment of sepsis. Extensive chemical studies revealed that XBJ injection contains amino acids, phenolic acids, flavonoid glycosides, terpeneglycosides and phthalides. In this study, the applicability of ultra high performance liquid chromatography coupled with high resolution hybrid quadruple-orbitrap mass spectrometry (UHPLC-Q-Orbitrap MS) for the simultaneous quantitative analysis of 30 bioactive constituents in XueBiJing injection (XBJ) was investigated. The mass spectrometer was operated in full MS scan mode. The use of 70,000FWHM mass resolution and narrow mass windows (5ppm) could effectively improve the selectivity of the method. Separation was achieved on a Waters ACQUITY UPLC(®) HSS C18 column (2.1mm×100mm, 1.8μm) with a gradient mobile phase consisting of acetonitrile-water (containing 10mM ammonium acetate) at a flow rate of 0.2mL/min. Satisfactory linearity was achieved within wide linear range and all correlation coefficients (r) of analytes were more than 0.9996. The limits of detection (LODs) were in the range of 0.1180-27.82ng/mL for different analytes. The relative standard deviations (RSDs) of inter- and intra-day precisions were less than 3.0% and the recoveries of the assay were in the range of 98.5%-101.5%. The validated method was successfully applied for simultaneous determination of 30 bioactive compounds in XueBiJing injection from 10 batches samples by UHPLC-Q-Orbitrap MS within 10min. Moreover, the results were evaluated principal component analysis and two compounds might be the most important chemical markers for chemical quality control of XBJ injection. The novel Q-Orbitrap mass spectrometry has been proved to be a very promising and powerful tool for routine screening of bioactive compounds in traditional Chinese medicine injection, ensuring drug safety and public health.

  17. AA, wide quadrupole on measurement stand

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    Please look up 8101024 first. Shims and washers on the wide quadrupoles (QFW, QDW; located in the lattice where dispersion was large) served mostly for corrections of those lattice parameters which were a function of momentum. After mounting shims and washers, the quadrupoles were measured to determine their magnetic centre and to catalogue the effect of washer constellations. Raymond Brown is busy measuring a wide quad.

  18. Oscillating Permanent Magnets.

    Science.gov (United States)

    Michaelis, M. M.; Haines, C. M.

    1989-01-01

    Describes several ways to partially levitate permanent magnets. Computes field line geometries and oscillation frequencies. Provides several diagrams illustrating the mechanism of the oscillation. (YP)

  19. Construction of Permanent-Magnet Electric Variable Transmissions for Hybrid Electric Vehicles%混合动力汽车用永磁式电气变速器的构建

    Institute of Scientific and Technical Information of China (English)

    程远; Christophe ESPANET; Rochdi TRIGUI; Alain BOUSCAYROL; 崔淑梅

    2011-01-01

    This paper presents a novel permanent-magnet electric variable transmission (PM-EVT) with an appropriate structure for hybrid electric vehicle (HEV) applications. Such a PM-EVT is similar to the wellknown series-parallel HEV (SP-HEV) of Toyota Prius, but with more integrated functions and simpler structures, with the planetary gear also eliminated. By analyzing four possible mechanical connections and different PM positions, a simplest structure of PM-EVT was finally chosen which has one stator, one inner rotor and one outer rotor, with the stator and inner rotor having independent windings, and the PMs located on the outer rotor. The results show that different PM arrangements on the outer rotor regard the machine performances and controllabilities.%提出了一种用于混合动力汽车(HEV)动力传动系统的新型结构的永磁式电气变速器(PM-EVT)。PM—EVT是一种与Toyota Prius混合动力汽车功能相似的串并联HEY传动系统,但是功能更加集成,结构更加简单,省去了用于功率分配的行星齿轮机构。分析了PM-EVT的4种可能的机械结构组合和永磁体配置,并选择其中最简单的一种作为最终方案:具有一个外定子、一个内转子、一个外转子;外定子和内转子分别有独立的三相绕组;永磁体分布在外转子上。分析结果表明:不同的永磁体配置形式具有不同的电机性能和控制性能。

  20. Performance Comparison of Permanent Magnet Linear Actuators of Different Mover Types

    DEFF Research Database (Denmark)

    Ritchie, Ewen; Hinov, K.; Yatchev, I.

    2006-01-01

    A comparative study of permanent magnet linear actuators with different location of the permanent magnet is reported. Three mover types are considered - soft magnetic mover, permanent magnet mover and hybrid mover. Force-stroke characteristics are obtained with the help of finite element models...

  1. SUPERCONDUCTING QUADRUPOLE ARRAYS FOR MULTIPLE BEAM TRANSPORT

    Energy Technology Data Exchange (ETDEWEB)

    Rainer Meinke

    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

  2. CLIC Main Beam Quadrupole Eigen Mode computation

    CERN Document Server

    Deleglise, Guillaume

    2010-01-01

    In this report, we summarise the work done on the CLIC Main Beam Quadrupole. There are about 4000 MB quadrupoles of 4 types with lengths ranging from 420mm to 1900mm. In order to obtain the desired CLIC luminosity, the MB quadrupoles have to be stable to 1nm above 1Hz. The region of interest for the study is between 0.5Hz and about 100Hz. In order to achieve the specifications, the magnet should not have any resonance peaks in this region of Interest. In addition, the magnet on its support shouldn’t have any resonance peak in the same frequency range. The first step is to determine if the designed magnet has its first resonance peak above 100Hz. We are studying the longest quadrupole more susceptible to internal resonances. In a second step, the magnet on ideal supporting points has been evaluated. The current magnet design can be seen on following figure. One can see that it is composed of 4 quadrants assembled so as to have a quadrupole magnetic field. As a last step, the mechanical model has been used to...

  3. Focusing properties of discrete RF quadrupoles

    Science.gov (United States)

    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)

  4. Resonance methods in quadrupole ion traps

    Science.gov (United States)

    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.

  5. Axial flux permanent magnet brushless machines

    CERN Document Server

    Gieras, Jacek F; Kamper, Maarten J

    2008-01-01

    Axial Flux Permanent Magnet (AFPM) brushless machines are modern electrical machines with a lot of advantages over their conventional counterparts. They are being increasingly used in consumer electronics, public life, instrumentation and automation system, clinical engineering, industrial electromechanical drives, automobile manufacturing industry, electric and hybrid electric vehicles, marine vessels and toys. They are also used in more electric aircrafts and many other applications on larger scale. New applications have also emerged in distributed generation systems (wind turbine generators

  6. Analytical transfer matrix of a quadrupole fringe

    Institute of Scientific and Technical Information of China (English)

    PENG Yue-Mei; XU Gang

    2011-01-01

    The analytical linear transfer matrices for different quadrupole fringes including quadratic,high order power and exponential models are deduced in this paper.As an example,the transfer matrices of the quadrupole BEPC Ⅱ 105Q are computed for the above three models and compared with hard edge and sliceby-slice models in cases of near 60° and 90° FODO cells.These models' results are much better than the hard edge model's,and can meet the requirement of accurate calculation.

  7. Permanences GAG-EPA

    CERN Multimedia

    GAC-EPA

    2015-01-01

    Le GAC organise chaque mois des permanences avec entretiens individuels. La prochaine permanence se tiendra le : Mardi 5 mai de 13 h 30 à 16 h 00 Salle de réunion de l’Association du personnel Les permanences suivantes auront lieu les mardis 2 juin, 1er septembre, 6 octobre, 3 novembre et 1er décembre 2015. Les permanences du Groupement des Anciens sont ouvertes aux bénéficiaires de la Caisse de pensions (y compris les conjoints survivants) et à tous ceux qui approchent de la retraite. Nous invitons vivement ces derniers à s’associer à notre groupement en se procurant, auprès de l’Association du personnel, les documents nécessaires.

  8. AA, wide quadrupole on measurement stand

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    Please look up 8101024 and 8103203 first. Wide quadrupole (QFW, QDW) with end-shims and shimming washers on the measurement stand. With the measurement coil one measured the harmonics of the magnetic field, determined the magnetic centre, and catalogued the effect of washer constellations.

  9. General quadrupole nuclear shapes. An algebraic perspective

    Energy Technology Data Exchange (ETDEWEB)

    Leviatan, A. (Los Alamos National Lab. (LANL), NM (USA). Theoretical Div.); Shao Bin (Yale Univ., New Haven, CT (USA). Sloane Physics Lab.)

    1990-07-05

    Spherical, axial and non-axial quadrupole shapes are investigated within the algebraic interacting boson model. For each shape the hamiltonian is resolved into intrinsic and collective parts, normal modes are identified and intrinsic states are constructed. Special emphasis is paid to new features (e.g. rigid triaxiality and coexisting deformed shapes) that emerge in the presence of three-body interactions. (orig.).

  10. All systems go for LHC quadrupoles

    CERN Multimedia

    2003-01-01

    The series fabrication of the Main Quadrupole cold masses for the LHC has begun with the delivery of the first unit on February 12th. The superconducting dipole magnets required to bend the proton beams around the LHC are often in the news. Less famous, perhaps, but equally important are the 360 main quadrupole (MQ) magnets, which will perform the principal focusing around the 27 km ring. CERN and CEA-Saclay began collaborating on the development and prototyping of these magnets in 1989. This resulted in five highly successful quadrupole units - also known as short straight sections - one of which was integrated for testing in String 1, and two others of the final design in String 2. Once the tests had confirmed the validity of the design and realization, the fabrication of the 360 cold masses had to be transferred to industry. After highly competitive tendering, the German firm ACCEL Instruments was entrusted both with the construction of the quadrupole magnets themselves, and with their assembly into the co...

  11. Closed orbit response to quadrupole strength variation

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Model of an LHC superconducting quadrupole magnet

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    Model of a superconducting quadrupole magnet for the LHC project. These magnets are used to focus the beam by squeezing it into a smaller cross-section, a similar effect to a lens focusing light. However, each magnet only focuses the beam in one direction so alternating magnet arrangements are required to produce a fully focused beam.

  13. Laser-induced quadrupole-quadrupole collisional energy transfer in Xe-Kr

    Institute of Scientific and Technical Information of China (English)

    Lu Zhen-Zhong; Chen De-Ying; Fan Rong-Wei; Xia Yuan-Qin

    2011-01-01

    By considering the relative velocity distribution function and multipole expansion interaction Hamiltonian, a three-state model for calculating the cross section of laser-induced quadrupole-quadrupole collisional energy transfer is presented. Calculated results in Xe-Kr system show that in the present system, the laser-induced collision process occurs for ~4 ps, which is much shorter than the dipole-dipole laser-induced collisional energy transfer (LICET) process.The spectrum of laser-induced quadrupole-quadrupole collisional energy transfer in Xe-Kr system has wider tunable range in an order of magnitude than the dipole-dipole LICET spectra. The peak cross section decreases and moves to the quasi-static wing with increasing temperature and the full width at half peak of the profile becomes larger as the system temperature increases.

  14. Pharmaceutical metabolite profiling using quadrupole/ion mobility spectrometry/time-of-flight mass spectrometry.

    Science.gov (United States)

    Chan, Eric C Y; New, Lee Sun; Yap, Chun Wei; Goh, Lin Tang

    2009-02-01

    The use of hybrid quadrupole ion mobility spectrometry time-of-flight mass spectrometry (Q/IMS/TOFMS) in the metabolite profiling of leflunomide (LEF) and acetaminophen (APAP) is presented. The IMS drift times (T(d)) of the drugs and their metabolites were determined in the IMS/TOFMS experiments and correlated with their exact monoisotopic masses and other in silico generated structural properties, such as connolly molecular area (CMA), connolly solvent-excluded volume (CSEV), principal moments of inertia along the X, Y and Z Cartesian coordinates (MI-X, MI-Y and MI-Z), inverse mobility and collision cross-section (CCS). The correlation of T(d) with these parameters is presented and discussed. IMS/TOF tandem mass spectrometry experiments (MS(2) and MS(3)) were successfully performed on the N-acetyl-p-benzoquinoneimine glutathione (NAPQI-GSH) adduct derived from the in vitro microsomal metabolism of APAP. As comparison, similar experiments were also performed using hybrid triple quadrupole linear ion trap mass spectrometry (QTRAPMS) and quadrupole time-of-flight mass spectrometry (QTOFMS). The abilities to resolve the product ions of the metabolite within the drift tube and fragment the ion mobility resolved product ions in the transfer travelling wave-enabled stacked ring ion guide (TWIG) demonstrated the potential applicability of the Q/IMS/TOFMS technique in pharmaceutical metabolite profiling.

  15. Production of rubidium Bose-Einstein condensate in an optically-plugged magnetic quadrupole trap

    CERN Document Server

    Zhang, Dong-Fang; Kong, Ling-Ran; Li, Kai; Jiang, Kai-Jun

    2016-01-01

    We have experimentally produced rubidium Bose-Einstein condensate in an optically-plugged magnetic quadrupole (OPQ) trap. A far blue-detuned focused laser beam with a wavelength of 532 nm is plugged in the center of the magnetic quadrupole trap to increase the number of trapped atoms and suppress the heating. A radio frequency (RF) evaporative cooling in the magneto-optical hybrid trap is applied to decrease the atom temperature into degeneracy. The atom number of the condensate is $1.2(0.4)\\times10^5$ and the temperature is below 100 nK. We have also studied characteristic behaviors of the condensate, such as phase space density (PSD), condensate fraction and anisotropic expansion.

  16. Application of permanent magnets in accelerators and electron storage rings

    Science.gov (United States)

    Halbach, K.

    1985-04-01

    The use of permanent-magnet systems in high-energy accelerators and as sources of synchrotron radiation in electron-storage rings is discussed in a review of recent experimental investigations. Consideration is given to the generic advantages of permanent magnets over electromagnets (higher field strength per magnet size) in small-scale configurations; the magnetic properties of some charge-sheet-equivalent-permanent-magnet materials (CSEMs); and the design of pure-CSEM and CSEM-Fe-hybrid multipole magnetic lenses, dipoles, and undulator/wiggler systems for use in free-electron lasers and the production of elliptically polarized synchrotron light. Drawings and diagrams are provided.

  17. Iron free permanent magnet systems for charged particle beam optics

    Energy Technology Data Exchange (ETDEWEB)

    Lund, S.M.; Halbach, K.

    1995-09-03

    The strength and astounding simplicity of certain permanent magnet materials allow a wide variety of simple, compact configurations of high field strength and quality multipole magnets. Here we analyze the important class of iron-free permanent magnet systems for charged particle beam optics. The theory of conventional segmented multipole magnets formed from uniformly magnetized block magnets placed in regular arrays about a circular magnet aperture is reviewed. Practical multipole configurations resulting are presented that are capable of high and intermediate aperture field strengths. A new class of elliptical aperture magnets is presented within a model with continuously varying magnetization angle. Segmented versions of these magnets promise practical high field dipole and quadrupole magnets with an increased range of applicability.

  18. LARP Long Nb3Sn Quadrupole Design.

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Exterior and interior metrics with quadrupole moment

    CERN Document Server

    Quevedo, Hernando

    2010-01-01

    We present the Ernst potential and the line element of an exact solution of Einstein's vacuum field equations that contains as arbitrary parameters the total mass, the angular momentum, and the quadrupole moment of a rotating mass distribution. We show that in the limiting case of slowly rotating and slightly deformed configuration, there exists a coordinate transformation that relates the exact solution with the approximate Hartle solution. It is shown that this approximate solution can be smoothly matched with an interior perfect fluid solution with physically reasonable properties. This opens the possibility of considering the quadrupole moment as an additional physical degree of freedom that could be used to search for a realistic exact solution, representing both the interior and exterior gravitational field generated by a self-gravitating axisymmetric distribution of mass of perfect fluid in stationary rotation.

  20. Splice testing for LHC quadrupole magnets

    CERN Document Server

    Barzi, E; Fehér, S; Kashikhin, V V; Kerby, J S; Lamm, M J; Orris, D; Ray, G; Tartaglia, M; Zlobin, A V

    2003-01-01

    Electrical splices between NbTi Rutherford type cables need to be made for the LHC IR inner triplet quadrupoles. Splices between magnets as well as internal to the magnets are necessary. Various splice configurations, solders, and fluxes have been considered. Testing of these splices at cryogenic temperatures and at various currents has been completed. The results were satisfactory; Fermilab is capable of making excellent low resistance (<1n Omega ) solder joints for the LHC project. (4 refs).

  1. Electrostatic quadrupole DC accelerators for BNCT applications

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Quadrupole transitions revealed by Borrmann spectroscopy.

    Science.gov (United States)

    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.

  3. TOUTATIS: A radio frequency quadrupole code

    OpenAIRE

    Romuald Duperrier

    2000-01-01

    A cw high power linear accelerator can only work with very low particle losses and structure activation. At low energy, the radio frequency quadrupole (RFQ) is an accelerator element that is very sensitive to losses. To design this structure, a good understanding of the beam dynamics is required. Generally, the reference code PARMTEQM is enough to design the accelerator. TOUTATIS has been written with the goals of cross-checking results and obtaining more reliable dynamics. This paper relates...

  4. CLIC quadrupole stabilization and nano-positioning

    CERN Document Server

    Collette, C; Artoos, K; Fernandez Carmona, P; Guinchard, M; Hauviller, C

    2010-01-01

    In the Compact LInear Collider (CLIC) currently under study, electrons and positrons will be accelerated in two linear accelerators to collide at the interaction point with an energy of 0.5- 3 TeV. This machine is constituted of a succession of accelerating structures, used to accelerate the beams of particles, and electromagnets (quadrupoles) used to focus the beams. In order to ensure good performances, the quadrupoles have to be extremely stable. Additionally, they should also have the capability to move by steps of some tens of nanometers every 20 ms with a precision of +/- 1nm. This paper proposes a holistic approach to fulfill alternatively both requirements using the same device. The concept is based on piezoelectric hard mounts to isolate the quadrupoles from the ground vibrations in the sensitive range between 1 and 20 Hz, and to provide nano-positioning capabilities. It is also shown that this strategy ensures robustness to external forces (acoustic noise, water flow for the cooling, air flow for th...

  5. Table of nuclear electric quadrupole moments

    Science.gov (United States)

    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.

  6. Contribution of electric quadrupole and dipole-quadrupole interference terms in Coulomb breakup of 15C

    Science.gov (United States)

    Singh, P.; Kharb, S.; Singh, M.

    2014-02-01

    The effects of electric quadrupole ( E2) and dipole-quadrupole interference ( E1- E2) terms in the Coulomb breakup of 15C have been investigated within the framework of eikonal approximation. The sensitivity of Coulomb breakup cross section, differential in relative energy and Longitudinal Momentum Distribution (LMD) of core fragments, towards these terms have been examined. A very small (1% of E1) contribution of E2 transition has been predicted in integrated Coulomb breakup cross section. Further it is also found that the inclusion of E2 and E1- E2 terms introduces a small asymmetry in the peak of relative energy spectrum and also increases the peak height of the spectrum. The contribution of dipole-quadrupole interference terms is clearly shown in LMD, as it introduces an asymmetry in the shape of LMD and enhances the matching between the data and predictions.

  7. Permanent magnet design methodology

    Science.gov (United States)

    Leupold, Herbert A.

    1991-01-01

    Design techniques developed for the exploitation of high energy magnetically rigid materials such as Sm-Co and Nd-Fe-B have resulted in a revolution in kind rather than in degree in the design of a variety of electron guidance structures for ballistic and aerospace applications. Salient examples are listed. Several prototype models were developed. These structures are discussed in some detail: permanent magnet solenoids, transverse field sources, periodic structures, and very high field structures.

  8. Lawful Permanent Residents - Annual Report

    Data.gov (United States)

    Department of Homeland Security — A lawful permanent resident (LPR) or 'green card' recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  9. Recent Advances on Permanent Magnet Machines

    Institute of Scientific and Technical Information of China (English)

    诸自强

    2012-01-01

    This paper overviews advances on permanent magnet(PM) brushless machines over last 30 years,with particular reference to new and novel machine topologies.These include current states and trends for surface-mounted and interior PM machines,electrically and mechanically adjusted variable flux PM machines including memory machine,hybrid PM machines which uniquely integrate PM technology into induction machines,switched and synchronous reluctance machines and wound field machines,Halbach PM machines,dual-rotor PM machines,and magnetically geared PM machines,etc.The paper highlights their features and applications to various market sectors.

  10. Nuclear electric quadrupole interactions in liquids entrapped in cavities

    Energy Technology Data Exchange (ETDEWEB)

    Furman, Gregory B., E-mail: gregoryf@bgu.ac.il; Meerovich, Victor M.; Sokolovsky, Vladimir L. [Ben Gurion University of the Negev, Physics Department (Israel)

    2016-12-15

    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.

  11. Validation of a qualitative screening method for pesticides in fruits and vegetables by gas chromatography quadrupole-time of flight mass spectrometry with atmospheric pressure chemical ionization

    NARCIS (Netherlands)

    Portoles, T.; Mol, J.G.J.; Sancho, J.V.; Lopez, F.J.; Hernandez, F.

    2014-01-01

    A wide-scope screening method was developed for the detection of pesticides in fruit and vegetables. The method was based on gas chromatography coupled to a hybrid quadrupole time-of-flight mass spectrometer with an atmospheric pressure chemical ionization source (GC-(APCI)QTOF MS). A non-target acq

  12. Identification of in vitro metabolites of ethylphenidate by liquid chromatography coupled to quadrupole time-of-flight mass spectrometry

    OpenAIRE

    Negreira, Noelia; Erratico, Claudio; Nuijs, van, Alexander L.N.; Covaci, Adrian

    2016-01-01

    Abstract: Ethylphenidate is a new potent synthetic psychoactive drug, structurally related to methylphenidate. Using human liver microsomes and cytosol, we have investigated for the first time the Phase-I and Phase-II in vitro metabolism of ethylphenidate. The structure of the metabolites was elucidated by hybrid quadrupole time-of-flight mass spectrometry. Overall, seven Phase-I, but no Phase-II metabolites were detected. Ethylphenidate underwent hydroxylation forming two primary mono-hydrox...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Distinguishing the nonjet azimuth quadrupole from QCD jets and hydrodynamic flows via 2D angular correlations and quadrupole spectrum analysis

    CERN Document Server

    Trainor, Thomas A

    2016-01-01

    According to the flow narrative commonly applied to high-energy nuclear collisions a 1D cylindrical-quadrupole component of 2D angular correlations conventionally denoted by quantity $v_2$ is interpreted to represent elliptic flow: azimuth modulation of transverse or radial flow in noncentral nucleus-nucleus (A-A) collisions. The nonjet (NJ) quadrupole component exhibits various properties inconsistent with a flow or hydro interpretation, including the observation that NJ-quadrupole centrality variation in $A$-$A$ collisions has no relation to strongly-varying jet modification ("jet quenching") in those collisions commonly attributed to jet interaction with a dense flowing medium. In the present study I report isolation of quadrupole spectra from $p_t$-differential $v_2(p_t)$ data obtained at the relativistic heavy ion collider (RHIC) and large hadron collider (LHCr). I demonstrate that NJ quadrupole spectra have characteristics very different from the single-particle spectra for most hadrons, that quadrupole...

  16. Quadrupole Transfer Function for Emittance Measurement

    CERN Document Server

    Cameron, Peter; Jansson, Andreas; Tan, Cheng-Yang

    2008-01-01

    Historically the use of the quadrupole moment measurement has been impeded by the requirement for large dynamic range, as well as measurement sensitivity to beam position. We investigate the use of the transfer function technique [1-3] in combination with the sensitivity and 160dB revolution line rejection of the direct diode detection analog front end [4] to open the possibility of an emittance diagnostic that may be implemented without operational complication, quasi- parasitic to the operation of existing tune measurement systems. Such a diagnostic would be particularly useful as an emittance monitor during acceleration ramp development in machines like RHIC and the LHC.

  17. A Compact High Gradient Pulsed Magnetic Quadrupole

    CERN Document Server

    Shuman, Derek; Kireeff Covo, Michel; Ritchie, Gary; Seidl, Peter

    2005-01-01

    A design for a high gradient, low inductance pulsed quadrupole magnet is presented. The magnet is a circular current dominated design with a circular iron return yoke. Features include a five turn eddy current compensated solid conductor coil design which theoretically eliminates the first four higher order multipole field components, a single layer "non-spiral bedstead" coil design which both minimizes utilization of radial space and maximizes utilization of axial space, and allows incorporation of steering and correction coils within existing radial space. The coils are wound and stretched straight in a special winder, then bent in simple fixtures to form the upturned ends, simplifying fabrication and assembly.

  18. Multi-Pass Quadrupole Mass Analyzer

    Science.gov (United States)

    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

  19. Nuclear quadrupole resonance echoes from hexamethylenetetramine.

    Science.gov (United States)

    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.

  20. Precise calculations of the deuteron quadrupole moment

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Franz L. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    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.

  1. Permanence can be Defended.

    Science.gov (United States)

    McGee, Andrew; Gardiner, Dale

    2017-03-01

    In donation after the circulatory-respiratory determination of death (DCDD), the dead donor rule requires that the donor be dead before organ procurement can proceed. Under the relevant limb of the Uniform Determination of Death Act 1981 (USA), a person is dead when the cessation of circulatory-respiratory function is 'irreversible'. Critics of current practice in DCDD have argued that the donor is not dead at the time organs are procured, and so the procurement of organs from these donors violates the dead donor rule. We offer a new argument here in defence of current DCDD practice, and, in particular, of the interpretation of the requirement of 'irreversibility' as permanence.

  2. Pulsars: Cosmic Permanent 'Neutromagnets'?

    CERN Document Server

    Hansson, Johan

    2011-01-01

    We argue that pulsars may be spin-polarized neutron stars, i.e. cosmic permanent magnets. This would simply explain several observational facts about pulsars, including the 'beacon effect' itself i.e. the static/stable misalignment of rotational and magnetic axes, the extreme temporal stability of the pulses and the existence of an upper limit for the magnetic field strength - coinciding with the one observed in "magnetars". Although our model admittedly is speculative, this latter fact seems to us unlikely to be pure coincidence.

  3. Consistent quadrupole-octupole collective model

    Science.gov (United States)

    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.

  4. Lower Extremity Permanent Dialysis Vascular Access.

    Science.gov (United States)

    Parekh, Vishal B; Niyyar, Vandana D; Vachharajani, Tushar J

    2016-09-07

    Hemodialysis remains the most commonly used RRT option around the world. Technological advances, superior access to care, and better quality of care have led to overall improvement in survival of patients on long-term hemodialysis. Maintaining a functioning upper extremity vascular access for a prolonged duration continues to remain a challenge for dialysis providers. Frequently encountered difficulties in clinical practice include (1) a high incidence of central venous catheter-related central vein stenosis and (2) limited options for creating a functioning upper extremity permanent arteriovenous access. Lack of surgical skills, fear of complications, and limited involvement of the treating nephrologists in the decision-making process are some of the reasons why lower extremity permanent dialysis access remains an infrequently used option. Similar to upper extremity vascular access options, lower extremity arteriovenous fistula remains a preferred access over arteriovenous synthetic graft. The use of femoral tunneled catheter as a long-term access should be avoided as far as possible, especially with the availability of newer graft-catheter hybrid devices. Our review provides a summary of clinical evidence published in surgical, radiology, and nephrology literature highlighting the pros and cons of different types of lower extremity permanent dialysis access.

  5. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    Science.gov (United States)

    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.

  6. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    Science.gov (United States)

    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.

  7. Intrinsic Third Order Aberrations in Electrostatic and Magnetic Quadrupoles

    CERN Document Server

    Baartman, R

    2015-01-01

    Intrinsic aberrations are those which occur due to the finite length of the desired field configuration. They are often loosely ascribed to the fringing field. This is misleading as it implies that the effects can be minimized by shaping the fields. In fact, there is an irreducible component related to the broken symmetry. It is present even in the hard-edge limit, and moreover, the other (soft-edge) effects can be simply ascribed to the intrinsic aberration spread over a finite length. We rederive the aberration formulas for quadrupoles using a Hamiltonian formalism. This allows for an easy comparison of electrostatic and magnetic quadrupoles. For different combinations of large and small emittances in the two transverse planes, it is found that in some situations electrostatic quadrupoles have lower aberrations, while in others, magnetic quadrupoles are better. As well, we discuss the ways in which existing transport codes handle quadrupole fringe fields. Pitfalls are pointed out and improvements proposed.

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

    CERN Document Server

    Trainor, Thomas A

    2016-01-01

    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 $v_2$ and interpreted to represent elliptic flow. Jet angular correlations may also contribute to $v_2$ data as "nonflow" depending on the method used to calculate $v_2$, 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 modification ("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 $v_2(p_t)$ data from the RHIC and LHC. I demonstrate that quadrupole spectra have characteristics very different from the single-particle spectra for most hadrons, that quad...

  9. Excited-State Dipole and Quadrupole Moments: TD-DFT versus CC2.

    Science.gov (United States)

    Jacquemin, Denis

    2016-08-09

    The accuracies of the excited-state dipole and quadrupole moments obtained by TD-DFT are assessed by considering 16 different exchange-correlation functionals and more than 30 medium and large molecules. Except for excited-state presenting a significant charge-transfer character, a relatively limited dependency on the nature of the functional is found. It also turns out that while DFT ground-state dipole moments tend to be too large, the reverse trend is obtained for their excited-state counterparts, at least when hybrid functionals are used. Consequently, the TD-DFT excess dipole moments are often too small, an error that can be fortuitously corrected for charge-transfer transition by selecting a pure or a hybrid functional containing a small share of exact exchange. This error-cancelation phenomena explains the contradictory conclusions obtained in previous investigations. Overall, the largest correlation between CC2 and TD-DFT excess dipoles is obtained with M06-2X, but at the price of a nearly systematic underestimation of this property by ca. 1 D. For the excess quadrupole moments, the average errors are of the order of 0.2-0.6 D·Å for the set of small aromatic systems treated.

  10. Quadrupole magnet for a rapid cycling synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Witte, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    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.

  11. Quench Protection of the LHC Quadrupole Magnets

    CERN Document Server

    Kurfuerst, Christoph; Dehning, Bernd; Sapoinski, Mariusz

    2010-01-01

    CERNs Large Hadron Collider (LHC) is a new high energy proton accelerator and storage ring. Its design allows to reach unprecedented beam energies and beam intensities, resulting in a largely increased particle physics discovery potential. The combination of its high beam energy and intensity may lead to beam losses which can have a severe impact on the LHC equipment and damage sensitive elements. To protect those and to measure operational losses, a Beam Loss Monitoring system has been installed all along the ring. The protection is achieved by extracting the beam from the ring in case thresholds imposed on measured radiation levels are exceeded. The thresholds are estimated through particle shower simulations. The simulated geometry and physic processes need to be precise in order to determine an optimum value, which therefore assures a high availability of the LHC for operation. This study is focused on the interconnection region between the main dipole and the main quadrupole magnet of the LHC. Six monito...

  12. Atomic Quadrupole Moment Measurement Using Dynamic Decoupling.

    Science.gov (United States)

    Shaniv, R; Akerman, N; Ozeri, R

    2016-04-01

    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.

  13. TOUTATIS: A radio frequency quadrupole code

    Directory of Open Access Journals (Sweden)

    Romuald Duperrier

    2000-12-01

    Full Text Available A cw high power linear accelerator can only work with very low particle losses and structure activation. At low energy, the radio frequency quadrupole (RFQ is an accelerator element that is very sensitive to losses. To design this structure, a good understanding of the beam dynamics is required. Generally, the reference code PARMTEQM is enough to design the accelerator. TOUTATIS has been written with the goals of cross-checking results and obtaining more reliable dynamics. This paper relates the different numerical methods used in the code. It is time based, using multigrids methods and adaptive mesh for a fine description of the forces without being time consuming. The field is calculated through a Poisson solver and the vanes are fully described, allowing it to properly simulate the coupling gaps and the RFQs extremities. Theoretical and experimental tests are also described and show a good agreement between simulations and reference cases.

  14. Magnetic quadrupoles lens for hot spot proton imaging in inertial confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Teng, J. [Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Gu, Y.Q., E-mail: yqgu@caep.cn [Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Center for Applied Physics and Technology, HEDPS, Peking University, Beijing 100871 (China); Chen, J.; Zhu, B.; Zhang, B.; Zhang, T.K.; Tan, F.; Hong, W.; Zhang, B.H. [Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Wang, X.Q. [Academy of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China)

    2016-08-01

    Imaging of DD-produced protons from an implosion hot spot region by miniature permanent magnetic quadrupole (PMQ) lens is proposed. Corresponding object-image relation is deduced and an adjust method for this imaging system is discussed. Ideal point-to-point imaging demands a monoenergetic proton source; nevertheless, we proved that the blur of image induced by proton energy spread is a second order effect therefore controllable. A proton imaging system based on miniature PMQ lens is designed for 2.8 MeV DD-protons and the adjust method in case of proton energy shift is proposed. The spatial resolution of this system is better than 10 μm when proton yield is above 10{sup 9} and the spectra width is within 10%.

  15. Permanent deformation of asphalt mixes

    NARCIS (Netherlands)

    Muraya, P.M.

    2007-01-01

    This dissertation describes the results of a research that was conducted on the permanent deformation of asphalt mixtures. Central to this research was the separate characterization of the contribution of the aggregate skeleton and the bituminous mortar towards resistance to permanent deformation. T

  16. Permanent-Magnet Meissner Bearing

    Science.gov (United States)

    Robertson, Glen A.

    1994-01-01

    Permanent-magnet meissner bearing features inherently stable, self-centering conical configuration. Bearing made stiffer or less stiff by selection of magnets, springs, and spring adjustments. Cylindrical permanent magnets with axial magnetization stacked coaxially on rotor with alternating polarity. Typically, rare-earth magnets used. Magnets machined and fitted together to form conical outer surface.

  17. Metabolite Profile of Salidroside in Rats by Ultraperformance Liquid Chromatography Coupled with Quadrupole Time-of-Flight Mass Spectrometry and High-Performance Liquid Chromatography Coupled with Quadrupole-Linear Ion Trap Mass Spectrometry.

    Science.gov (United States)

    Hu, Zhiwei; Wang, Ziming; Liu, Yong; Wu, Yan; Han, Xuejiao; Zheng, Jian; Yan, Xiufeng; Wang, Yang

    2015-10-21

    In the present work, the salidroside metabolite profile in rat urine was investigated, and subsequently the metabolic pathways of salidroside were proposed. After administrations of salidroside at an oral dose of 100 or 500 mg/kg, rat urine samples were collected and pretreated with methanol to precipitate the proteins. The pretreated samples were analyzed by an Acquity ultraperformance liquid chromatography (UPLC) coupled with an HSS T3 column and detected by quadrupole time-of-flight mass spectrometry (Q-TOF-MS) or high-performance liquid chromatography coupled with hybrid triple-quadrupole linear ion trap mass spectrometry (HPLC/Q-trap-MS). A total of eight metabolites were detected and identified on the basis of the characteristics of their protonated ions in the urine samples. The results elucidated that salidroside was metabolized via glucuronidation, sulfation, deglycosylation, hydroxylation, methylation, and dehydroxylation pathways in vivo.

  18. The "Permanent" Patient Problem.

    Science.gov (United States)

    Bruce, Courtenay R; Majumder, Mary A

    2014-01-01

    Patients who enter the health care system for acute care may become "permanent" patients of the hospital when a lack of resources precludes discharge to the next level of post-acute care. Legal, professional, and ethical norms prohibit physician and acute care hospital "dumping" of these patients. However, limitless use of hospital resources for indefinite stays is untenable. In the absence of hospital policy addressing this specific issue, the availability of financial support will be determined by health care professionals' willingness to advocate for the patient and negotiate with hospital administrators and the ability and willingness of administrators to authorize the use of hospital resources. We propose five mid-level ethical principles to guide advocacy and administrative decision-making about provision of financial support for post-acute care for those patients who cannot afford it. We use two actual, de-identified cases to illustrate how these principles can be used to make reasoned, consistent decisions about the provision of post-acute financial support.

  19. Development of Superconducting Focusing Quadrupoles for Heavy Ion Drivers

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Emission of nuclear quadrupole resonance from polycrystalline hexamethylenetetramine.

    Science.gov (United States)

    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.

  1. Spin and quadrupole contributions to the motion of astrophysical binaries

    CERN Document Server

    Steinhoff, Jan

    2014-01-01

    Compact objects in general relativity approximately move along geodesics of spacetime. It is shown that the corrections to geodesic motion due to spin (dipole), quadrupole, and higher multipoles can be modeled by an extension of the point mass action. The quadrupole contributions are discussed in detail for astrophysical objects like neutron stars or black holes. Implications for binaries are analyzed for a small mass ratio situation. There quadrupole effects can encode information about the internal structure of the compact object, e.g., in principle they allow a distinction between black holes and neutron stars, and also different equations of state for the latter. Furthermore, a connection between the relativistic oscillation modes of the object and a dynamical quadrupole evolution is established.

  2. ISR Superconducting Quadrupole under test in its cryostat

    CERN Multimedia

    1979-01-01

    One of the Superconducting Quadrupoles for the ISR high luminosity (low-beta) insertion is seen here during final test in building 230 before installation in the ISR. See also photos 7812609X and 7702690X.

  3. End view of ISR Superconducting Quadrupole in its cryostat

    CERN Multimedia

    1977-01-01

    This view shows the cold mass of the prototype ISR Superconducting Quadrupole suspended to the outer vacuum tank by means of titanium alloy rods.The heat shield wrapped with superinsulation can also be seen. See also photo 7702690X.

  4. Electro-Magnetic Quadrupole Magnets in the LCLS FEL Undulator

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. PRINCIPLE OF SKEW QUADRUPOLE MODULATION TO MEASURE BETATRON COUPLING.

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Harmonic analysis and field quality improvement of an HTS quadrupole magnet for a heavy ion accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhan; Wei, Shaoqing; Lee, Sang Jin [Uiduk University, Gyeongju (Korea, Republic of); Jo, Hyun Chul; Kim, Do Gyun; Kim, Jong Won [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)

    2016-06-15

    In recent years, the iron-dominated high-temperature superconductor (HTS) quadrupole magnets are being developed for heavy ion accelerators. Field analyses for iron-dominated quadrupole magnets were based on the normal-conducting (NC) quadrupole magnet early in the development for accelerators. Some conclusions are still in use today. However, the magnetic field of iron-dominated HTS quadrupole magnets cannot fully follow these conclusions. This study established an HTS quadrupole magnet model and an NC quadrupole magnet model, respectively. The harmonic characteristics of two magnets were analyzed and compared. According to the comparison, the conventional iron-dominated quadrupole magnets can be designed for maximum field gradient; the HTS quadrupole magnet, however, should be considered with varying field gradient. Finally, the HTS quadrupole magnet was designed for the changing field gradient. The field quality of the design was improved comparing with the result of the previous study. The new design for the HTS quadrupole magnet has been suggested.

  7. Relaxation of quadrupole orientation in an optically pumped alkali vapour

    Energy Technology Data Exchange (ETDEWEB)

    Bernabeu, E.; Tornos, J.

    1985-04-01

    The relaxation of quadrupole orientation (alignment) in an optically pumped alkali vapour is theoretically studied by taking into account the relaxation processes by alkali-buffer gas, alkali-alkali with spin exchange and alkali-cell wall (diffusion process) collisions. The relaxation transients of the quadrupole orientation are obtained by introducing a first-order weak-pumping approximation (intermediate pumping) less restrictive than the usually considered (zeroth order) one.

  8. Quadrupole collectivity in {sup 128}Cd

    Energy Technology Data Exchange (ETDEWEB)

    Boenig, Esther Sabine

    2014-07-07

    The regions around shell closures, especially around doubly magic nuclei, are of major interest in nuclear structure physics, as they provide a perfect test for nuclear structure theory. The neutron-rich Cd isotopes in the region of {sup 132}Sn are only two protons away from the shell closure at Z=50 and in close proximity to the N=82 magic number. Nevertheless they show an irregular behaviour regarding the excitation energy of the first excited 2{sup +} state. This is not reproduced by shell model calculations, which is astonishing due to the proximity of the shell closures. In order to shed light on the much discussed region around doubly magic {sup 132}Sn, a Coulomb excitation experiment of {sup 128}Cd has been performed at REX-ISOLDE, CERN. The reduced transition strength B(E2;0{sup +}{sub gs} → 2{sup +}{sub 1}), which is a measure of collectivity, and the spectroscopic quadrupole moment Q{sub s}(2{sup +}{sub 1}) as a measure of deformation could be determined for the first time. The results are shown as the continuation of already measured neutron-rich Cd isotopes and are compared to both beyond mean field and shell model calculations, which give different predictions for these observables.

  9. Nuclear spin squeezing via electric quadrupole interaction

    Science.gov (United States)

    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. Quadrupole Focusing Lenses for Charged Particles

    Energy Technology Data Exchange (ETDEWEB)

    Cork, Bruce; Zajec, Emery

    1953-04-15

    A set of four strong focusing magnetic quadrupole lenses has been constructed and operated. Each lens consists of four air cooled electromagnets with pole tips having a hyperbolic cross section. Each lens is 4 in. long and has an aperture 2 in. in diameter. Measurements of the magnetic field demonstrate that the hyperbolic cross section satisfies the requirements of a constant magnetic field gradient very well. The technique of deflecting a current carrying flexible wire has been used to measure the trajectory of charged particles through the system of lenses. It has been observed that the strong focusing requirements are satisfied. The system of lenses was then used to focus 0.5 Mev protons, 20 Mev deuterons, and 40 Mev alpha particles. The parallel beam of 0.5 Mev protons was detected by observing the incandescence of a quartz plate while the protons were bombarding it. The focused beam was less than 1 mm in diameter. The astigmatic 20 Mev deuteron beam from the 60 in. cyclotron was increased in current density by a factor greater than 30.

  11. Heavy-Fermion Superconductivity in the Quadrupole Ordered State of PrV2Al20

    Science.gov (United States)

    Tsujimoto, Masaki; Matsumoto, Yosuke; Tomita, Takahiro; Sakai, Akito; Nakatsuji, Satoru

    2014-12-01

    PrV2Al20 is a rare example of a heavy-fermion system based on strong hybridization between conduction electrons and nonmagnetic quadrupolar moments of the cubic Γ3 ground doublet. Here, we report that a high-quality single crystal of PrV2Al20 exhibits superconductivity at Tc=50 mK in the antiferroquadrupole-ordered state under ambient pressure. The heavy-fermion character of the superconductivity is evident from the specific heat jump of Δ C /T ˜0.3 J /mol K2 and the effective mass m*/m0˜140 estimated from the temperature dependence of the upper critical field. Furthermore, the high-quality single crystals exhibit double transitions at TQ=0.75 K and T*=0.65 K associated with quadrupole and octupole degrees of freedom of the Γ3 doublet. In the ordered state, the specific heat C /T shows a T3 dependence, indicating the gapless mode associated with the quadrupole order, the octupole order, or both. The strong sensitivity to impurity of the superconductivity suggests unconventional character due to significant quadrupolar fluctuations.

  12. Quantitative proteomics using the high resolution accurate mass capabilities of the quadrupole-orbitrap mass spectrometer.

    Science.gov (United States)

    Gallien, Sebastien; Domon, Bruno

    2014-08-01

    High resolution/accurate mass hybrid mass spectrometers have considerably advanced shotgun proteomics and the recent introduction of fast sequencing capabilities has expanded its use for targeted approaches. More specifically, the quadrupole-orbitrap instrument has a unique configuration and its new features enable a wide range of experiments. An overview of the analytical capabilities of this instrument is presented, with a focus on its application to quantitative analyses. The high resolution, the trapping capability and the versatility of the instrument have allowed quantitative proteomic workflows to be redefined and new data acquisition schemes to be developed. The initial proteomic applications have shown an improvement of the analytical performance. However, as quantification relies on ion trapping, instead of ion beam, further refinement of the technique can be expected.

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

    Science.gov (United States)

    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

  14. High quality proton beams from hybrid integrated laser-driven ion acceleration systems

    Energy Technology Data Exchange (ETDEWEB)

    Sinigardi, Stefano, E-mail: sinigardi@bo.infn.it [Dipartimento di Fisica e Astronomia, Università di Bologna and INFN Sezione di Bologna, Via Irnerio 46, I-40126 Bologna (Italy); Turchetti, Giorgio; Rossi, Francesco; Londrillo, Pasquale [Dipartimento di Fisica e Astronomia, Università di Bologna and INFN Sezione di Bologna, Via Irnerio 46, I-40126 Bologna (Italy); Giove, Dario; De Martinis, Carlo [Dipartimento di Fisica, Università di Milano and INFN Sezione di Milano, Via F.lli Cervi 201, I-20090 Segrate (Italy); Bolton, Paul R. [Kansai Photon Science Institute (JAEA), Umemidai 8-1-7, Kizugawa-shi, Kyoto 619-0215 (Japan)

    2014-03-11

    We consider a hybrid acceleration scheme for protons where the laser generated beam is selected in energy and angle and injected into a compact linac, which raises the energy from 30 to 60 MeV. The laser acceleration regime is TNSA and the energy spectrum is determined by the cutoff energy and proton temperature. The dependence of the spectrum on the target properties and the incidence angle is investigated with 2D PIC simulations. We base our work on widely available technologies and on laser with a short pulse, having in mind a facility whose cost is approximately 15M€. Using a recent experiment as the reference, we choose the laser pulse and target so that the energy spectrum obtained from the 3D PIC simulation is close to the one observed, whose cutoff energy was estimated to be over 50 MeV. Laser accelerated protons in the TNSA regime have wide energy spectrum and broad divergence. In this paper we compare three transport lines, designed to perform energy selection and beam collimation. They are based on a solenoid, a quadruplet of permanent magnetic quadrupoles and a chicane. To increase the maximum available energy, which is actually seen as an upper limit due to laser properties and available targets, we propose to inject protons into a small linac for post-acceleration. The number of selected and injected protons is the highest with the solenoid and lower by one and two orders of magnitude with the quadrupoles and the chicane respectively. Even though only the solenoid enables achieving to reach a final intensity at the threshold required for therapy with the highest beam quality, the other systems will be very likely used in the first experiments. Realistic start-to-end simulations, as the ones reported here, are relevant for the design of such experiments.

  15. High quality proton beams from hybrid integrated laser-driven ion acceleration systems

    Science.gov (United States)

    Sinigardi, Stefano; Turchetti, Giorgio; Rossi, Francesco; Londrillo, Pasquale; Giove, Dario; De Martinis, Carlo; Bolton, Paul R.

    2014-03-01

    We consider a hybrid acceleration scheme for protons where the laser generated beam is selected in energy and angle and injected into a compact linac, which raises the energy from 30 to 60 MeV. The laser acceleration regime is TNSA and the energy spectrum is determined by the cutoff energy and proton temperature. The dependence of the spectrum on the target properties and the incidence angle is investigated with 2D PIC simulations. We base our work on widely available technologies and on laser with a short pulse, having in mind a facility whose cost is approximately 15 M €. Using a recent experiment as the reference, we choose the laser pulse and target so that the energy spectrum obtained from the 3D PIC simulation is close to the one observed, whose cutoff energy was estimated to be over 50 MeV. Laser accelerated protons in the TNSA regime have wide energy spectrum and broad divergence. In this paper we compare three transport lines, designed to perform energy selection and beam collimation. They are based on a solenoid, a quadruplet of permanent magnetic quadrupoles and a chicane. To increase the maximum available energy, which is actually seen as an upper limit due to laser properties and available targets, we propose to inject protons into a small linac for post-acceleration. The number of selected and injected protons is the highest with the solenoid and lower by one and two orders of magnitude with the quadrupoles and the chicane respectively. Even though only the solenoid enables achieving to reach a final intensity at the threshold required for therapy with the highest beam quality, the other systems will be very likely used in the first experiments. Realistic start-to-end simulations, as the ones reported here, are relevant for the design of such experiments.

  16. Qualitative permanence of Lotka-Volterra equations.

    Science.gov (United States)

    Hofbauer, Josef; Kon, Ryusuke; Saito, Yasuhisa

    2008-12-01

    In this paper, we consider permanence of Lotka-Volterra equations. We investigate the sign structure of the interaction matrix that guarantees the permanence of a Lotka-Volterra equation whenever it has a positive equilibrium point. An interaction matrix with this property is said to be qualitatively permanent. Our results provide both necessary and sufficient conditions for qualitative permanence.

  17. Transient or permanent fisheye views

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper

    2012-01-01

    , about the benefits and limitations of transient visualizations. We describe an experiment that compares the usability of a fisheye view that participants could call up temporarily, a permanent fisheye view, and a linear view: all interfaces gave access to source code in the editor of a widespread......Transient use of information visualization may support specific tasks without permanently changing the user interface. Transient visualizations provide immediate and transient use of information visualization close to and in the context of the user’s focus of attention. Little is known, however...... programming environment. Fourteen participants performed varied tasks involving navigation and understanding of source code. Participants used the three interfaces for between four and six hours in all. Time and accuracy measures were inconclusive, but subjective data showed a preference for the permanent...

  18. Lodestone: Nature's own permanent magnet

    Science.gov (United States)

    Wasilewski, P.

    1976-01-01

    Magnetic hysteresis and microstructural details are presented which explain why the class of magnetic iron ores defined as proto-lodestones, can behave as permanent magnets, i.e. lodestones. Certain of these proto-lodestones which are not permanent magnets can be made into permanent magnets by charging in a field greater than 1000 oersted. This fact, other experimental observations, and field evidence from antiquity and the middle ages, which seems to indicate that lodestones are found as localized patches within massive ore bodies, suggests that lightning might be responsible for the charging of lodestones. The large remanent magnetization, high values of coercive force, and good time stability for the remanent magnetization are all characteristics of proto-lodestone iron ores which behave magnetically as fine scale ( 10 micrometer) intergrowths when subjected to magnetic hysteresis analysis. The magnetic results are easily understood by analysis of the complex proto lodestone microstructural patterns observable at the micrometer scale and less.

  19. Topology optimized permanent magnet systems

    CERN Document Server

    Bjørk, R; Insinga, A R

    2016-01-01

    Topology optimization of permanent magnet systems consisting of permanent magnets, high permeability iron and air is presented. An implementation of topology optimization for magnetostatics is discussed and three examples are considered. First, the Halbach cylinder is topology optimized with iron and an increase of 15% in magnetic efficiency is shown, albeit with an increase of 3.8 pp. in field inhomogeneity - a value compared to the inhomogeneity in a 16 segmented Halbach cylinder. Following this a topology optimized structure to concentrate a homogeneous field is shown to increase the magnitude of the field by 111% for the chosen dimensions. Finally, a permanent magnet with alternating high and low field regions is considered. Here a $\\Lambda_\\mathrm{cool}$ figure of merit of 0.472 is reached, which is an increase of 100% compared to a previous optimized design.

  20. Connecting Temporary and Permanent Organizing

    DEFF Research Database (Denmark)

    Stjerne, Iben Sandal; Velikova, Silviya Svejenova

    2016-01-01

    This paper investigates the relationship between a permanent organization and a series of temporary organizations. It draws on an in-depth study of the process through which a Danish film production company, seeking to balance innovation and persistence in a troubled industry, struggles to realize...... a novel children’s film and its sequels. The study reveals tensions at different levels as well as boundary work and boundary roles that address them, bringing in shadows of past and future projects. The study extends the understanding of the dialectic between temporary and permanent organizing...... by emphasizing how ongoing work at different boundaries affects the permanent and temporary organizing’s connectedness and outcomes. It also challenges the overly bracketed view of temporary organizations, suggesting a temporality perspective on temporariness....

  1. Linear Quadrupole Cooling Channel for a Neutrino Factory

    CERN Document Server

    Johnstone, Carol; Makino, Kyoko

    2005-01-01

    The staging and optimization in the design of a Neutrino Factory are critically dependent on the choice and format of accelerator. Possibly the simplest, lowest-cost scenario is a nonscaling FFAG machine coupled to a linear (no bending) transverse cooling channel constructed from the simplest quadrupole lens system, a FODO cell. In such a scenario, transverse cooling demands are reduced by a factor of 4 and no longitudinal cooling is required relative to acceleration using a Recirculating Linac (RLA). Detailed simulations further show that a quadrupole-based channel cools efficiently and over a momentum range which is well-matched to FFAG acceleration. Details and cooling performance for a quadrupole channel are summarized in this work.

  2. Electromagnetic acceleration of permanent magnets

    CERN Document Server

    Dolya, S N

    2015-01-01

    We consider the acceleration of the permanent magnets, consisting of neodymium iron boron by means of the running magnetic field gradient. It is shown that the specific magnetic moment per nucleon in neodymium iron boron is determined by the remained magnetization of the substance. The maximum accessable gradient of the magnetic field accelerating the permanent magnets is determined by the coercive force thirty kilogauss. For the neodymium iron boron magnets this gradient is equal to twenty kilogauss divided by one centimeter. The finite velocity of the magnets six kilometers per second, the length of acceleration is six hundred thirty-seven meters.

  3. Early eruption of permanent canines.

    Science.gov (United States)

    Madhu, S

    2012-01-01

    Systemic and local factors can modify the eruption time of teeth. Generalized eruption time changes could be due to some systemic diseases like hyperthyroidism, hypophosphatasia, precocious puberty, Proteus syndrome, etc. Localized early eruption of permanent teeth could be due to early extraction of deciduous teeth. Presented here is an extremely rare case of early eruption of permanent canines in a 7-year old female child. Though the number of such cases is very limited, the clinician should poses adequate knowledge and keeps an open eye to identify such cases.

  4. Early eruption of permanent canines

    Directory of Open Access Journals (Sweden)

    S Madhu

    2012-01-01

    Full Text Available Systemic and local factors can modify the eruption time of teeth. Generalized eruption time changes could be due to some systemic diseases like hyperthyroidism, hypophosphatasia, precocious puberty, Proteus syndrome, etc. Localized early eruption of permanent teeth could be due to early extraction of deciduous teeth. Presented here is an extremely rare case of early eruption of permanent canines in a 7-year old female child. Though the number of such cases is very limited, the clinician should poses adequate knowledge and keeps an open eye to identify such cases.

  5. Quadrupole collectivity in silicon isotopes approaching neutron number N=28

    Science.gov (United States)

    Campbell, C. M.; Aoi, N.; Bazin, D.; Bowen, M. D.; Brown, B. A.; Cook, J. M.; Dinca, D.-C.; Gade, A.; Glasmacher, T.; Horoi, M.; Kanno, S.; Motobayashi, T.; Riley, L. A.; Sagawa, H.; Sakurai, H.; Starosta, K.; Suzuki, H.; Takeuchi, S.; Terry, J. R.; Yoneda, K.; Zwahlen, H.

    2007-08-01

    Quadrupole deformation parameters, |β|, have been deduced for 36,38,40Si from measured inelastic proton-scattering cross sections. Due to the strong Z=14 subshell gap, low-lying quadrupole collectivity in these nuclei is attributed to the excitation of valence neutrons. Enhanced collectivity at N=26 indicates a reduced N=28 shell gap at large neutron excess in this chain of isotopes. Data are compared to large-scale shell-model calculations and prior Coulomb excitation measurements on 36,38Si.

  6. Low-frequency quadrupole impedance of undulators and wigglers

    Science.gov (United States)

    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 ).

  7. Extension of the Measurement Capabilities of the Quadrupole Resonator

    CERN Document Server

    Junginger, Tobias; Welsch, Carsten

    2012-01-01

    The Quadrupole Resonator, designed to measure the surface resistance of superconducting samples at 400 MHz has been refurbished. The accuracy of its RF-DC compensation measurement technique is tested by an independent method. It is shown that the device enables also measurements at 800 and 1200 MHz and is capable to probe the critical RF magnetic field. The electric and magnetic field configuration of the Quadrupole Resonator are dependent on the excited mode. It is shown how this can be used to distinguish between electric and magnetic losses.

  8. Magnetic Fields: Visible and Permanent.

    Science.gov (United States)

    Winkeljohn, Dorothy R.; Earl, Robert D.

    1983-01-01

    Children will be able to see the concept of a magnetic field translated into a visible reality using the simple method outlined. Standard shelf paper, magnets, iron filings, and paint in a spray can are used to prepare a permanent and well-detailed picture of the magnetic field. (Author/JN)

  9. Overview on permanent magnetic actuator

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Permanent magnetic actuator (PMA), as a new electronic actuator of vacuum circuit breakers, certainly will be used to replace the traditional mechanical actuator. It has such advantages as simple structure, high reliability, free maintenance, and so on. This paper summarizes the development, structure, magnetic analysis, character analysis, and control strategy of PMA, and also predicts the future trend of PMA development

  10. Synchronous motor with hybrid permanent magnets on the rotor.

    Science.gov (United States)

    Slusarek, Barbara; Kapelski, Dariusz; Antal, Ludwik; Zalas, Pawel; Gwoździewicz, Maciej

    2014-07-10

    Powder metallurgy allows designers of electric motors to implement new magnetic circuit structures. A relatively new concept is the use of a magnet system consisting of various types of magnets on one rotor, for example sintered and bonded magnets. This concept has been applied to the design and manufacture of the four-pole rotor of a synchronous motor with 400 W power and a rotational speed of 1500 rpm. In this motor, the stator of an asynchronous motor type Sh 71-4B is applied. The application of the new construction of the rotor resulted in an increase in motor efficiency and power factor compared to an asynchronous motor with the same volume.

  11. Design and Analysis of Tubular Permanent Magnet Linear Wave Generator

    Directory of Open Access Journals (Sweden)

    Jikai Si

    2014-01-01

    Full Text Available Due to the lack of mature design program for the tubular permanent magnet linear wave generator (TPMLWG and poor sinusoidal characteristics of the air gap flux density for the traditional surface-mounted TPMLWG, a design method and a new secondary structure of TPMLWG are proposed. An equivalent mathematical model of TPMLWG is established to adopt the transformation relationship between the linear velocity of permanent magnet rotary generator and the operating speed of TPMLWG, to determine the structure parameters of the TPMLWG. The new secondary structure of the TPMLWG contains surface-mounted permanent magnets and the interior permanent magnets, which form a series-parallel hybrid magnetic circuit, and their reasonable structure parameters are designed to get the optimum pole-arc coefficient. The electromagnetic field and temperature field of TPMLWG are analyzed using finite element method. It can be included that the sinusoidal characteristics of air gap flux density of the new secondary structure TPMLWG are improved, the cogging force as well as mechanical vibration is reduced in the process of operation, and the stable temperature rise of generator meets the design requirements when adopting the new secondary structure of the TPMLWG.

  12. Design and analysis of tubular permanent magnet linear wave generator.

    Science.gov (United States)

    Si, Jikai; Feng, Haichao; Su, Peng; Zhang, Lufeng

    2014-01-01

    Due to the lack of mature design program for the tubular permanent magnet linear wave generator (TPMLWG) and poor sinusoidal characteristics of the air gap flux density for the traditional surface-mounted TPMLWG, a design method and a new secondary structure of TPMLWG are proposed. An equivalent mathematical model of TPMLWG is established to adopt the transformation relationship between the linear velocity of permanent magnet rotary generator and the operating speed of TPMLWG, to determine the structure parameters of the TPMLWG. The new secondary structure of the TPMLWG contains surface-mounted permanent magnets and the interior permanent magnets, which form a series-parallel hybrid magnetic circuit, and their reasonable structure parameters are designed to get the optimum pole-arc coefficient. The electromagnetic field and temperature field of TPMLWG are analyzed using finite element method. It can be included that the sinusoidal characteristics of air gap flux density of the new secondary structure TPMLWG are improved, the cogging force as well as mechanical vibration is reduced in the process of operation, and the stable temperature rise of generator meets the design requirements when adopting the new secondary structure of the TPMLWG.

  13. Measurement of an atomic quadrupole moment using dynamic decoupling

    Science.gov (United States)

    Akerman, Nitzan; Shaniv, Ravid; Ozeri, Roee

    2016-05-01

    Some of the best clocks today are ion-based optical clocks. These clocks are referenced to a narrow optical transition in a trapped ion. An example for such a narrow transition is the electric quadrupole E 2 transition between states with identical parity. An important systematic shift of such a transition is the quadrupole shift resulting from the electric field gradient inherent to the ion trap. We present a new dynamic decoupling method that rejects magnetic field noise while measuring the small quadrupole shift of the optical clock transition. Using our sequence we measured the quadrupole moment of the 4D5/2 level in a trapped 88 Sr+ ion to be 2 .973-0 . 033 + 0 . 026 ea02 , where e is the electron charge and a0 is the Bohr radius. 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.

  14. Third-Order Apochromatic Drift-Quadrupole Beamline

    CERN Document Server

    Balandin, V; Decking, W; Golubeva, N

    2012-01-01

    In this paper we present the design of a straight drift-quadrupole system which can transport certain beam ellipses (apochromatic beam ellipses) without influence of the second and of the third order chromatic and geometric aberrations of the beamline transfer map.

  15. Prototype Superconducting Quadrupole for the ISR low-beta insertion

    CERN Multimedia

    CERN PhotoLab

    1977-01-01

    The picture shows the cold mass of the Quadrupole with its outer aluminium alloy rings pre-compressing the superconducting coils via the magnetic yoke split in 4 parts.The end of the inner vacuum chamber,supporting the 6-pole correction windings, can also be seen as well as the electrical connections. See also photos 7702690X, 7702307.

  16. Quadrupole moment of superdeformed bands in Tb-151

    NARCIS (Netherlands)

    Finck, C; Stezowski, O; Beck, FA; Appelbe, DE; Byrski, T; Courtin, S; Cullen, DM; Curien, D; de France, G; Duchene, G; Erturk, S; Gall, BJP; Garg, U; Haas, B; Khadiri, N; Kharraja, B; Kintz, N; Nourreddine, A; Prevost, D; Rigollet, C; Savajols, H; Twin, PJ; Vivien, JP; Zuber, K

    1998-01-01

    The quadrupole moments of the first two superdeformed (SD) bands in the nucleus Tb-151 have been measured with the Doppler Shift Attenuation Method (DSAM) using the EUROGAM gamma-ray spectrometer, The first excited band (B2) is identical to the yrast SD band of Dy-152 in terms of dynamical moments o

  17. ISR Superconducting Quadrupole Prototype:preparing the first test

    CERN Multimedia

    1976-01-01

    The photo shows the first prototype quadrupole (still with an adjustable stainless steel shrinking cylinder) being lifted to be inserted in a vertical cryostat for testing. It attained the design field gradient without any quench.The persons are Pierre Rey and Michel Bouvier. See also 7702690X.

  18. Detection of quadrupole relaxation in an optically pumped cesium vapour

    Energy Technology Data Exchange (ETDEWEB)

    Bernabeu, E.; Tornos, J.

    1985-10-01

    The relaxation of quadrupole orientation induced by means of optical pumping in a cesium vapour is experimentally studied, and the results are compared to the theoretical predictions. The optical detection process of this type of orientation is also discussed as a function of the polarization and spectral profile of the detection light.

  19. Alignment-to-orientation conversion and nuclear quadrupole resonance

    CERN Document Server

    Budker, D; Rochester, S M; Urban, J T

    2003-01-01

    The role of alignment-to-orientation conversion (AOC) in nuclear quadrupole resonance (NQR) is discussed. AOC is shown to be the mechanism responsible for the appearance of macroscopic orientation in a sample originally lacking any global polarization. Parallels are drawn between NQR and AOC in atomic physics.

  20. Quadrupole moment of superdeformed bands in Tb-151

    NARCIS (Netherlands)

    Finck, C; Stezowski, O; Beck, FA; Appelbe, DE; Byrski, T; Courtin, S; Cullen, DM; Curien, D; de France, G; Duchene, G; Erturk, S; Gall, BJP; Garg, U; Haas, B; Khadiri, N; Kharraja, B; Kintz, N; Nourreddine, A; Prevost, D; Rigollet, C; Savajols, H; Twin, PJ; Vivien, JP; Zuber, K

    The quadrupole moments of the first two superdeformed (SD) bands in the nucleus Tb-151 have been measured with the Doppler Shift Attenuation Method (DSAM) using the EUROGAM gamma-ray spectrometer, The first excited band (B2) is identical to the yrast SD band of Dy-152 in terms of dynamical moments

  1. PERMANENT-MAGNET INDUCTION GENERATORS: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    K. S. S. RAMAKRISHNAN

    2011-06-01

    Full Text Available The advantage of using a permanent-magnet induction generator (PMIG instead of a conventional induction generator is its ability to suppress inrush current during system linking when synchronous input is performed. Induction machines excited with permanent-magnet (PM are called permanent-magnet induction generators. This paper presents an exhaustive survey of the literature discussing the classification of permanent-magnet machines, process of permanent-magnet excitation and voltage build-up, modelling, steady-state and performance analysis of the permanent-magnet induction generators.

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

    Science.gov (United States)

    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. Manganese-based Permanent Magnets

    Directory of Open Access Journals (Sweden)

    Ian Baker

    2015-08-01

    Full Text Available There is a significant gap between the energy product, BH, where B is the magnetic flux density and H is the magnetic field strength, of both the traditional ferrite and AlNiCo permanent magnets of less than 10 MGOe and that of the rare earth magnets of greater than 30 MGOe. This is a gap that Mn-based magnets could potentially, inexpensively, fill. This Special Issue presents work on the development of both types of manganese permanent magnets. Some of the challenges involved in the development of these magnets include improving the compounds’ energy product, increasing the thermal stability of these metastable compounds, and producing them in quantity as a bulk material.[...

  4. Automated phenotyping of permanent crops

    Science.gov (United States)

    McPeek, K. Thomas; Steddom, Karl; Zamudio, Joseph; Pant, Paras; Mullenbach, Tyler

    2017-05-01

    AGERpoint is defining a new technology space for the growers' industry by introducing novel applications for sensor technology and data analysis to growers of permanent crops. Serving data to a state-of-the-art analytics engine from a cutting edge sensor platform, a new paradigm in precision agriculture is being developed that allows growers to understand the unique needs of each tree, bush or vine in their operation. Autonomous aerial and terrestrial vehicles equipped with multiple varieties of remote sensing technologies give AGERpoint the ability to measure key morphological and spectral features of permanent crops. This work demonstrates how such phenotypic measurements combined with machine learning algorithms can be used to determine the variety of crops (e.g., almond and pecan trees). This phenotypic and varietal information represents the first step in enabling growers with the ability to tailor their management practices to individual plants and maximize their economic productivity.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  6. Trans-permanent magnetic actuation

    Science.gov (United States)

    Farmer, Daniel Jay

    The demands for an actuator to deploy, position and shape large spaced-based structures form a unique set of design criteria. In many applications it is desirable to hold displacements or forces between two points to within specified requirements (the regulation problem) and to periodically to change position (the tracking problem). Furthermore, the interest generally lies in satisfying the dynamic performance requirements while expending minimal power, while meeting tight tolerances and while experiencing little wear and fatigue. The actuator must also be able to withstand a variety of operational conditions such as impacts and thermal changes over an extended period of time. Current trends in large-scale structures have addressed the demands by using conventional actuators and motors, along with elaborate linkages or mechanisms to shape, position, protect and deploy. The developed designs use unique characteristics of permanent magnets to create simple direct-acting actuators and motors very suitable for space based structures. The developed trans-permanent magnetic (T-PM) actuators and motors are systems consisting of one or more permanent magnets, some of whose magnetic strengths can be switched on-board by surrounding pulse-coils. The T-PM actuator and motors expend no power during regulation. The T-PM can periodically change or remove the strength of its own magnets thereby enabling both fine-tune adjustments (microsteps) and large-scale adjustments (rotation). The fine (microstep) adjustments are particularly helpful in thermally varying space environments. The large-scale adjustments (rotation) are particularly helpful in deployment where the structure or antenna must experience large-angle rotations and/or large displacements. T-PM concepts are illustrated in direct acting actuators and built into stepper motor and permanent magnet motor applications. Several examples of design, analysis and testing are developed to verify the technology and supporting

  7. The cycloid Permanent Magnetic Gear

    DEFF Research Database (Denmark)

    Rasmussen, Peter Omand; Andersen, Torben Ole; Jørgensen, Frank T.

    2008-01-01

    This paper presents a new permanent-magnet gear based on the cycloid gearing principle. which normally is characterized by an extreme torque density and a very high gearing ratio. An initial design of the proposed magnetic gear was designed, analyzed, and optimized with an analytical model...... regarding torque density. The results were promising as compared to other high-performance magnetic-gear designs. A test model was constructed to verify the analytical model....

  8. Multipole contribution from an off-axis orbit in an IR quadrupole and the consequences on the dynamic aperture

    Science.gov (United States)

    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.

  9. Hybrid spacecraft attitude control system

    Directory of Open Access Journals (Sweden)

    Renuganth Varatharajoo

    2016-02-01

    Full Text Available The hybrid subsystem design could be an attractive approach for futurespacecraft to cope with their demands. The idea of combining theconventional Attitude Control System and the Electrical Power System ispresented in this article. The Combined Energy and Attitude ControlSystem (CEACS consisting of a double counter rotating flywheel assemblyis investigated for small satellites in this article. Another hybrid systemincorporating the conventional Attitude Control System into the ThermalControl System forming the Combined Attitude and Thermal ControlSystem (CATCS consisting of a "fluid wheel" and permanent magnets isalso investigated for small satellites herein. The governing equationsdescribing both these novel hybrid subsystems are presented and theironboard architectures are numerically tested. Both the investigated novelhybrid spacecraft subsystems comply with the reference missionrequirements.The hybrid subsystem design could be an attractive approach for futurespacecraft to cope with their demands. The idea of combining theconventional Attitude Control System and the Electrical Power System ispresented in this article. The Combined Energy and Attitude ControlSystem (CEACS consisting of a double counter rotating flywheel assemblyis investigated for small satellites in this article. Another hybrid systemincorporating the conventional Attitude Control System into the ThermalControl System forming the Combined Attitude and Thermal ControlSystem (CATCS consisting of a "fluid wheel" and permanent magnets isalso investigated for small satellites herein. The governing equationsdescribing both these novel hybrid subsystems are presented and theironboard architectures are numerically tested. Both the investigated novelhybrid spacecraft subsystems comply with the reference missionrequirements.

  10. Permanent magnets including undulators and wigglers

    OpenAIRE

    Bahrdt, J.

    2011-01-01

    After a few historic remarks on magnetic materials we introduce the basic definitions related to permanent magnets. The magnetic properties of the most common materials are reviewed and the production processes are described. Measurement techniques for the characterization of macroscopic and microscopic properties of permanent magnets are presented. Field simulation techniques for permanent magnet devices are discussed. Today, permanent magnets are used in many fields. This article concentrat...

  11. Electron scale nested quadrupole Hall field in Cluster observations of magnetic reconnection

    CERN Document Server

    Jain, Neeraj

    2014-01-01

    This Letter presents the first evidence of a new and unique feature of spontaneous reconnection at multiple sites in electron current sheet, viz. nested quadrupole structure of Hall field at electron scales, in Cluster observations. The new nested quadrupole is a consequence of electron scale processes in reconnection. Whistler response of the upstream plasma to the interaction of electron flows from neighboring reconnection sites produces a large scale quadrupole Hall field enclosing the quadrupole fields of the multiple sites, thus forming a nested structure. Electron-magnetohydrodynamic simulations of an electron current sheet yields mechanism of the formation of nested quadrupole.

  12. 21 CFR 886.4445 - Permanent magnet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Permanent magnet. 886.4445 Section 886.4445 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove...

  13. Modelling and optimization of a permanent-magnet machine in a flywheel

    NARCIS (Netherlands)

    Holm, S.R.

    2003-01-01

    This thesis describes the derivation of an analytical model for the design and optimization of a permanent-magnet machine for use in an energy storage flywheel. A prototype of this flywheel is to be used as the peak-power unit in a hybrid electric city bus. The thesis starts by showing the feasibili

  14. Permanent-File-Validation Utility Computer Program

    Science.gov (United States)

    Derry, Stephen D.

    1988-01-01

    Errors in files detected and corrected during operation. Permanent File Validation (PFVAL) utility computer program provides CDC CYBER NOS sites with mechanism to verify integrity of permanent file base. Locates and identifies permanent file errors in Mass Storage Table (MST) and Track Reservation Table (TRT), in permanent file catalog entries (PFC's) in permit sectors, and in disk sector linkage. All detected errors written to listing file and system and job day files. Program operates by reading system tables , catalog track, permit sectors, and disk linkage bytes to vaidate expected and actual file linkages. Used extensively to identify and locate errors in permanent files and enable online correction, reducing computer-system downtime.

  15. Cryogenic Hybrid Magnetic Bearing

    Science.gov (United States)

    Meeks, Crawford R.; Dirusso, Eliseo; Brown, Gerald V.

    1994-01-01

    Cryogenic hybrid magnetic bearing is example of class of magnetic bearings in which permanent magnets and electromagnets used to suspend shafts. Electromagnets provide active control of position of shaft. Bearing operates at temperatures from -320 degrees F (-196 degrees C) to 650 degrees F (343 degrees C); designed for possible use in rocket-engine turbopumps, where effects of cryogenic environment and fluid severely limit lubrication of conventional ball bearings. This and similar bearings also suitable for terrestrial rotating machinery; for example, gas-turbine engines, high-vacuum pumps, canned pumps, precise gimbals that suspend sensors, and pumps that handle corrosive or gritty fluids.

  16. A twin aperture resistive quadrupole for the LHC

    CERN Document Server

    Clark, G S; de Rijk, G; Racine, M

    2000-01-01

    The European Organization for Nuclear Research (CERN) is constructing the Large Hadron Collider (LHC). The LHC's cleaning insertions require 48 twin aperture resistive quadrupoles. These 3.1 m long magnets have a gradient of 35 T/m for an inscribed circle of 46 mm diameter and an aperture separation distance of 224 mm. This magnet project is part of the Canadian contribution to the LHC. A prototype magnet was delivered in May 1998 and measured at CERN. Design changes were made based on the results. Due to the small apertures and the complicated geometry, the mechanical precision of the laminations and stacks is the main issue in the production of these quadrupoles. Series production will start in October 1999. The design and the measurement results are described in this paper. (1 refs).

  17. Low-frequency quadrupole impedance of undulators and wigglers

    Directory of Open Access Journals (Sweden)

    A. Blednykh

    2016-10-01

    Full Text Available 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 μ_{r}. 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 (μ_{r}→∞, and the case in which the magnets are fully saturated (μ_{r}=1.

  18. Nuclear quadrupole coupling interactions in the rotational spectrum of tryptamine

    Science.gov (United States)

    Alonso, J. L.; Cortijo, V.; Mata, S.; Pérez, C.; Cabezas, C.; López, J. C.; Caminati, W.

    2011-09-01

    Four conformers of tryptamine have been detected in a supersonic expansion and characterized by laser ablation molecular beam Fourier transform microwave spectroscopy LA-MB-FTMW in the 5-10 GHz frequency range. The quadrupole hyperfine structure originated by two 14N nuclei has been completely resolved for all conformers and used for their unambiguous identification. Nuclear quadrupole coupling constants of the nitrogen atom of the side chain have been used to determine the orientation of the amino group involved in N-H⋯π interactions: to the π electronic system of the pyrrole unit in the Gauche-Pyrrole conformers (GPy) or to the phenyl unit in the Gauche-Phenyl ones.

  19. 120-mm superconducting quadrupole for interaction regions of hadron colliders

    CERN Document Server

    Zlobin, A V; Mokhov, N V; Novitski, I

    2012-01-01

    Magnetic and mechanical designs of a Nb3Sn 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.

  20. Chlorine Nuclear Quadrupole Hyperfine Structure in the Vinyl - Chloride Complex

    Science.gov (United States)

    Leung, Helen O.; Marshall, Mark D.; Messinger, Joseph P.

    2015-06-01

    The microwave spectrum of the vinyl chloride--hydrogen chloride complex, presented at last year's symposium, is greatly complicated by the presence of two chlorine nuclei as well as an observed, but not fully explained tunneling motion. Indeed, although it was possible at that time to demonstrate conclusively that the complex is nonplanar, the chlorine nuclear quadrupole hyperfine splitting in the rotational spectrum resisted analysis. With higher resolution, Balle-Flygare Fourier transform microwave spectra, the hyperfine structure has been more fully resolved, but appears to be perturbed for some rotational transitions. It appears that knowledge of the quadrupole coupling constants will provide essential information regarding the structure of the complex, specifically the location of the hydrogen atom in HCl. Our progress towards obtaining values for these constants will be presented.

  1. Beta Function Measurement in the Tevatron Using Quadrupole Gradient Modulation

    CERN Document Server

    Jansson, Andreas; Volk, James T

    2005-01-01

    Early in Run2, there was an effort to compare the different emittance measurements in the Tevatron (flying wires and synchtotron light) and understand the origin of the observed differences. To measure the beta function at a few key locations near the instruments, air-core quadrupoles were installed. By modulating the gradient of these magents and measuring the effect on the tune, the lattice parameters can be extracted. Initially, the results seem to disagree with with other methods. At the time, the lattice was strongly coupled due to a skew component in the main dipoles, caused by sagging of the cryostat. After a large fraction of the superconducting magnets were shimmed to remove a strong skew quadrupole component, the results now agree with expectations, confirming that the beta function is not the major error source of discrepancy in the emittance measurement.

  2. Quadrupole association and dissociation of hydrogen in the early Universe

    Science.gov (United States)

    Forrey, Robert C.

    2016-10-01

    Radiative association and photodissociation rates are calculated for quadrupole transitions of H2. A complete set of bound and unbound states are included in a self-consistent master equation to obtain steady-state concentrations for a dilute system of hydrogen atoms and molecules. Phenomenological rate constants computed from the steady-state concentrations satisfy detailed balance for any combination of matter and radiation temperature. Simple formulas are derived for expressing the steady-state distributions in terms of equilibrium distributions. The rate constant for radiative association is found to be generally small for all temperature combinations. The photodissociation rate constant for quadrupole transitions is found to dominate the rate constants for other H2 photodestruction mechanisms for {T}{{R}} ≤slant 3000 K. Implications for the formation and destruction of H2 in the early Universe are discussed.

  3. Quadrupole association and dissociation of hydrogen in the early Universe

    CERN Document Server

    Forrey, Robert C

    2016-01-01

    Radiative association and photodissociation rates are calculated for quadrupole transitions of H2. A complete set of bound and unbound states are included in a self-consistent master equation to obtain steady-state concentrations for a dilute system of hydrogen atoms and molecules. Phenomenological rate constants computed from the steady-state concentrations satisfy detailed balance for any combination of matter and radiation temperature. Simple formulas are derived for expressing the steady-state distributions in terms of equilibrium distributions. The rate constant for radiative association is found to be generally small for all temperature combinations. The photodissociation rate constant for quadrupole transitions is found to dominate the rate constants for other H2 photodestruction mechanisms for radiation temperatures less than or equal to 3000 K. Implications for the formation and destruction of H2 in the early universe are discussed.

  4. Prototype of Superconducting Quadrupole for ISR Low-Beta Insertion

    CERN Multimedia

    1977-01-01

    In colliders, smaller beam cross-section means higher luminosity. Beam-size being proportional to the square-root of the "beta function" value, a small beta means small beam size, hence high luminosity. The first p-p collision in the ISR occurred in January 1971 and in 1973 a study was launched on low-beta insertions, which focus beams to even smaller sizes at the beam crossing points. In 1976 the first prototype of a superconducting quadrupole was tested. Here we see Theodor Tortschanoff with a prototype of 1.25 m magnetic length. Manufacture of 8 quadrupoles (4 of L=1.15 m, 4 of L=0.65 m) began at Alsthom in 1978. They were installed at point 8 of the ISR, enhancing luminosity there until final low-beta operation in December 1983. For details see "Yellow Report" CERN 76-16.

  5. Generating Low Beta Regions with Quadrupoles for Final Muon Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, J. G. [Mississippi U.; Cremaldi, L. M. [Mississippi U.; Hart, T. L. [Mississippi U.; Oliveros, S. J. [Mississippi U.; Summers, D. J. [Mississippi U.; Neuffer, D. V. [Fermilab

    2017-05-01

    Muon beams and colliders are rich sources of new physics, if muons can be cooled. A normalized rms transverse muon emittance of 280 microns has been achieved in simulation with short solenoids and a betatron function of 3 cm. Here we use ICOOL, G4beamline, and MAD-X to explore using a 400 MeV/c muon beam and strong focusing quadrupoles to approach a normalized transverse emittance of 100 microns and finish 6D muon cooling. The low beta regions produced by the quadrupoles are occupied by dense, low Z absorbers, such as lithium hydride or beryllium, that cool the beam. Equilibrium transverse emittance is linearly proportional to the beta function. Reverse emittance exchange with septa and/or wedges is then used to decrease transverse emittance from 100 to 25 microns at the expense of longitudinal emittance for a high energy lepton collider. Work remains to be done on chromaticity correction.

  6. High Gradient $Nb_3Sn$ Quadrupole Demonstrator MKQXF Engineering Design

    CERN Document Server

    Kokkinos, C; Karppinen, Mikko; CERN. Geneva. ATS Department

    2016-01-01

    A new mechanical design concept for the $Nb_3Sn$ quadrupoles has been developed with a goal of an accelerator quality magnet that can be industrially produced in large series. This concept can easily be extended to any length and applied on both 1-in-1 and 2-in-1 configurations. It is based on the pole-loading concept and collared coils using dipole-type collars. Detailed design optimisation of a demonstrator magnet based on present base-line HL-LHC IR quadrupole QXF coil geometry has been carried out including the end regions. This report describes the design concept and the fully parametric multi-physics finite element (FE) models that were used to determine the optimal assembly parameters including the effects of the manufacturing tolerances.

  7. CERN Permanent exhibitions short version

    CERN Multimedia

    2016-01-01

    Visits Explore by yourself the issues CERN's physicists are trying to solve: given that the entire universe is made of particles, where do they come from? Why do they behave in the way they do? Discover the massive apparatus used by physicists at CERN, like the LHC, and see how each part works. CERN invites the public to discover the mysteries of the Universe and the work of the world's biggest physics laboratory through free of charge guided tours and permanent exhibitions. As a group, with friends, individually, on foot, on your bike, come and discover CERN or explore it virtually. Welcome!

  8. Prospects for Non-Rare Earth Permanent Magnets for Traction Motors and Generators

    Science.gov (United States)

    Kramer, M. J.; McCallum, R. W.; Anderson, I. A.; Constantinides, S.

    2012-07-01

    With the advent of high-flux density permanent magnets based on rare earth elements such as neodymium (Nd) in the 1980s, permanent magnet-based electric machines had a clear performance and cost advantage over induction machines when weight and size were factors such as in hybrid electric vehicles and wind turbines. However, the advantages of the permanent magnet-based electric machines may be overshadowed by supply constraints and high prices of their key constituents, rare earth elements, which have seen nearly a 10-fold increase in price in the last 5 years and the imposition of export limits by the major producing country, China, since 2010. We outline the challenges, prospects, and pitfalls for several potential alloys that could replace Nd-based permanent magnets with more abundant and less strategically important elements.

  9. Wooden models of an AA quadrupole between bending magnets

    CERN Multimedia

    1978-01-01

    At two points in the AA lattice, a quadrupole (QDN, defocusing, narrow) was tightly wedged between two bending magnets (BST, short, wide). This picture of wooden models lets one imagine the strong interaction between their magnetic fields. There was no way one could calculate with the necessary accuracy the magnetic effects and their consequences for the machine optics. The necessary corrections were made after measurements with a circulating beam, in a tedious iterative procedure, with corrrection coils and shims.

  10. Testing the Dipole and Quadrupole Moments of Galactic Models

    OpenAIRE

    Briggs, Michael S.; Paciesas, William S.; Pendleton, Geoffrey N.; Meegan, Charles A.; Fishman, Gerald J.; Horack, John M.; Kouveliotou, Chryssa; Hartmann, Dieter H.; Hakkila, Jon

    1996-01-01

    If gamma-ray bursts originate in the Galaxy, at some level there should be a galactic pattern in their distribution on the sky. We test published galactic models by comparing their dipole and quadrupole moments with the moments of the BATSE 3B catalog. While many models have moments that are too large, several models are in acceptable or good agreement with the data.

  11. Electrostatic quadrupole focusing in the AGS g-2 storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, G.; Larsen, R.; Morse, W.; Semertzidis, Y.; Yelk, J. [Brookhaven National Lab., Upton, NY (United States); Liu, Z. [Boston Univ., MA (United States). Dept. of Physics

    1993-06-01

    Electrostatic quadrupole focusing is to be used in the high precision measurement of the anomalous magnetic moment of the muon, AGS Experiment 821. The final design uses planar rather than hyperbolic electrodes, and the field is pulsed to minimize the effect of trapped electrons. The mechanical design is described. Performance in a 1.5T magnetic field at less than 10{sup {minus}6} Torr is reviewed.

  12. Electrostatic quadrupole focusing in the AGS g-2 storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, G.; Larsen, R.; Morse, W.; Semertzidis, Y.; Yelk, J. (Brookhaven National Lab., Upton, NY (United States)); Liu, Z. (Boston Univ., MA (United States). Dept. of Physics)

    1993-01-01

    Electrostatic quadrupole focusing is to be used in the high precision measurement of the anomalous magnetic moment of the muon, AGS Experiment 821. The final design uses planar rather than hyperbolic electrodes, and the field is pulsed to minimize the effect of trapped electrons. The mechanical design is described. Performance in a 1.5T magnetic field at less than 10[sup [minus]6] Torr is reviewed.

  13. Active quadrupole stabilization for future linear particle colliders

    CERN Document Server

    Collette, Christophe; Kuzmin, Andrey; Janssens, Stef; Sylte, Magnus; Guinchard, Michael; Hauviller, Claude

    2010-01-01

    The future Compact LInear particle Collider (CLIC) under study at CERN will require to stabilize heavy electromagnets, and also to provide them some positioning capabilities. Firstly, this paper presents the concept adopted to address both requirements. Secondly, the control strategy adopted for the stabilization is studied numerically, showing that the quadrupole can be stabilized in both lateral and vertical direction. Finally, the strategy is validated experimentally on a single degree of freedom scaled test bench.

  14. Short quadrupole, first at the SC, then at LEAR

    CERN Multimedia

    1982-01-01

    Quadrupoles of this type were built for the beam lines of the 600 MeV Synchro-Cylclotron. Surplus ones were installed in the LEAR injection line. The particularity of these quads is that they are very short and that a special design, resembling the "Lambertson magnet", limits and linearizes their stray field. This was achieved by the iron between the poles extending beyond the poles.

  15. General quadrupole shapes in the Interacting Boson Model

    Energy Technology Data Exchange (ETDEWEB)

    Leviatan, A.

    1990-01-01

    Characteristic attributes of nuclear quadrupole shapes are investigated within the algebraic framework of the Interacting Boson Model. For each shape the Hamiltonian is resolved into intrinsic and collective parts, normal modes are identified and intrinsic states are constructed and used to estimate transition matrix elements. Special emphasis is paid to new features (e.g. rigid triaxiality and coexisting deformed shapes) that emerge in the presence of the three-body interactions. 27 refs.

  16. Determining gaseous composition of fluid inclusions with quadrupole mass spectrometer

    Institute of Scientific and Technical Information of China (English)

    朱和平; 王莉娟

    2002-01-01

    Quadrupole mass spectrometer (QMS) is an instrument for effectively determining gaseous composition of fluid inclusion. The gaseous component is extracted from inclusions with thermal decrepitation method and then determined with the sensitive QMS instrument. The method is characterized by high sensitivity and high accuracy with the relative standard deviation (RSD, n = 6) of less than 3%. It has been successfully used for analyzing fluid inclusions. The analytical re-sults meet the requirement of geological study.

  17. Targeted Proteomic Quantification on Quadrupole-Orbitrap Mass Spectrometer*

    OpenAIRE

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

    2012-01-01

    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 degr...

  18. Mass Quadrupole as a Source of Naked Singularities

    CERN Document Server

    Quevedo, Hernando

    2010-01-01

    We investigate the gravitational field of a static mass with quadrupole moment in empty space. It is shown that in general this configuration is characterized by the presence of curvature singularities without a surrounding event horizon. These naked singularities generate an effective field of repulsive gravity which, in turn, drastically changes the behavior of test particles. As a possible consequence, the accretion disk around a naked singularity presents a particular discontinuous structure.

  19. NMR Probe as a Field Marker in a Quadrupole

    CERN Document Server

    Caspers, Friedhelm; CERN. Geneva. SPS and LEP Division

    1999-01-01

    A study has started to improve the reproducibility of the focusing elements of the SPS for its operation as LHC injector. This note is a copy of the oral presentation to the IMMW11 seminar, which took place at Brookhaven National Laboratory in September 1999. It indicates the feasibility of the creation of a "G-Train" via a NMR probe used as a field marker in a reference quadrupole.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Quadrupole Law and Steering Options in the Linac4 DTL

    CERN Document Server

    Stovall, J

    2009-01-01

    The Linac4 drift-tube linac (DTL) reference design has been modified to reduce the power consumption in tank 1 by adjusting the accelerating field and phase laws. In this note we investigate three options for the transverse focusing lattice, quadrupole law, and two options for beam steering. We use acceptance, sensitivity to alignment errors and the probabiity of beam loss as figures of merit for evaluating each option.

  2. Analysis of lamination measurements for CERN's twin aperture quadrupoles

    CERN Document Server

    Clark, G S

    2002-01-01

    The European Organization for Nuclear Research (CERN) is constructing the Large Hadron Collider (LHC). The LHC's cleaning insertions require 48 twin aperture resistive quadrupoles. The laminations for these magnets are punched from low carbon steel sheet 1.5 mm thick. To check the quality of the laminations, samples are regularly collected and measured. This paper describes how these measurements are analyzed. This work is part of the Canadian contribution to the LHC. (5 refs).

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  5. Focusing Strength Measurements of the Main Quadrupoles for the LHC

    CERN Document Server

    Smirnov, N; Calvi, M; Deferne, G; Di Marco, J; Sammut, N; Sanfilippo, S

    2006-01-01

    More than 1100 quadrupole magnets of different types are needed for the Large Hadron Collider (LHC) which is in the construction stage at CERN. The most challenging parameter to measure on these quadrupoles is the integrated gradient (Gdl). An absolute accuracy of 0.1% is needed to control the beta beating. In this paper we briefly describe the whole set of equipment used for Gdl measurements: Automated Scanner system, Single Stretched Wire system and Twin Coils system, concentrating mostly on their absolute accuracies. Most of the possible inherent effects that can introduce systematic errors are discussed along with their preventive methods. In the frame of this qualification some of the magnets were tested with two systems. The results of the intersystem cross-calibrations are presented. In addition, the qualification of the measurement system used at the magnet manufacturer's is based on results of more than 40 quadrupole assemblies tested in cold conditions at CERN and in warm conditions at the vendor si...

  6. In-situ Vibration Measurements of the CTF2 Quadrupoles

    CERN Document Server

    Coosemans, Williame

    2004-01-01

    The Compact LInear Collider (CLIC), presently under study at the European Organization for Nuclear Research (CERN), aims at colliding high energy â€ワnanobeams” at a luminosity of 1035 cm-2s-1. Vibrations of the lattice elements, if not properly corrected, can result in a loss in performance by creating both unacceptable emittance growth in the linear accelerator and relative beam-beam offsets at the interaction point. Of particular concern are the vibrations induced by the accelerator environment. For example, the circulating water used to cool the lattice quadrupoles will increase magnet vibration levels. In the framework of the CLIC stability study, in-situ measurements of quadrupole vibrations have been performed at the CLIC Test Facility 2 (CTF2) with all accelerator equipment switched on. Since the CTF2 quadrupoles and their alignment support structures are realistic prototypes of those to be used in the CLIC linac, the measurements provide a realistic estimate of the CLIC magnet vibrations in a...

  7. Development of a $Nb_{3}$Sn quadrupole magnet model

    CERN Document Server

    Devred, Arnaud; Gourdin, C; Juster, F P; Peyrot, M; Rey, J M; Rifflet, J M; Streiff, J M; Védrine, P

    2001-01-01

    One possible application of Nb/sub 3/Sn, whose superconducting properties far exceed those of NbTi, is the fabrication of short and powerful quadrupole magnets for the crowded interaction regions of large particle accelerators. To learn about Nb/sub 3/Sn technology and to evaluate fabrication techniques, DAPNIA/STCM at CEA/Saclay has undertaken an R&D program aimed at designing and building a 1 m-long, 56 mm single-aperture quadrupole magnet model. The model relies on the same coil geometry as the LHC arc quadrupole magnets, but has no iron yoke. It is expected to produce a nominal field gradient of 211 T/m at 11870 A. The coils are wound from Rutherford-type cables insulated with quartz fiber tapes, before being heat-treated and vacuum-impregnated with epoxy resin. Laminated, austenitic collars, locked around the coil assembly by means of keys restrain the Lorentz forces. After reviewing the conceptual design of the magnet model, we report on the cable and cable insulation development programs and we pre...

  8. Final 6D Muon Ionization Colling using Strong Focusing Quadrupoles

    Energy Technology Data Exchange (ETDEWEB)

    Hart, T. L. [Mississippi U.; Acosta, J. G. [Mississippi U.; Cremaldi, L. M. [Mississippi U.; Oliveros, S. J. [Mississippi U.; Summers, D. J. [Mississippi U.; Neuffer, D. V. [Fermilab

    2016-11-15

    Abstract Low emittance muon beam lines and muon colliders are potentially a rich source of BSM physics for future exper- imenters. A muon beam normalized emittance of ax,y,z = (280, 280, 1570)µm has been achieved in simulation with short solenoids and a betatron function of 3 cm. Here we use ICOOL and MAD-X to explore using a 400 MeV/c muon beam and strong focusing quadrupoles to achieve a normalized transverse emittance of 100 µm and complete 6D cooling. The low beta regions, as low as 5 mm, produced by the quadrupoles are occupied by dense, low Z absorbers, such as lithium hydride or beryllium, that cool the beam transversely. Equilibrium transverse emittance is linearly proportional to the transverse betatron function. Reverse emittance exchange with septa and/or wedges is then used to decrease transverse emittance from 100 to 25 µm at the expense of longitudinal emittance for a high energy lepton collider. Cooling challenges include chromaticity correction, ssband overlap, quadrupole acceptance, and staying in phase with RF.

  9. Position Stability Monitoring of THEthe LCLS Undulator Quadrupoles

    Energy Technology Data Exchange (ETDEWEB)

    Nuhn, Heinz Dieter; Gassner, Georg; Peters, Franz; /SLAC

    2012-03-26

    X-ray FELs demand that the positions of undulator components be stable to less than 1 {mu}m per day. Simultaneously, the undulator length increases significantly in order to saturate at x-ray wavelengths. To minimize the impact of the outside environment, the Linac Coherent Light Source (LCLS) undulator is placed underground, but reliable data about ground motion inside such a tunnel was not available in the required stability range during the planning phase. Therefore, a new position monitor system had been developed and installed with the LCLS undulator. This system is capable of measuring x, y, roll, pitch and yaw of each of the 33 undulator quadrupoles with respect to stretched wires. Instrument resolution is about 10 nm and instrument drift is negligible. Position data of individual quadrupoles can be correlated along the entire 132-m long undulator. The system has been under continuous operation since 2009. This report describes long term experiences with the running system and the observed positional stability of the undulator quadrupoles.

  10. Real-Time Quantitative Analysis of H2, He, O2, and Ar by Quadrupole Ion Trap Mass Spectrometry

    Science.gov (United States)

    Ottens, Andrew K.; Harrison, W. W.; Griffin, Timothy P.; Helms, William R.; Voska, N. (Technical Monitor)

    2002-01-01

    The use of a quadrupole ion trap mass spectrometer for quantitative analysis of hydrogen and helium as well as other permanent gases is demonstrated. The customized instrument utilizes the mass selective instability mode of mass analysis as with commercial instruments; however, this instrument operates at a greater RF trapping frequency and without a buffer gas. With these differences, a useable mass range from 2 to over 50 Da is achieved, as required by NASA for monitoring the Space Shuttle during a launch countdown. The performance of the ion trap is evaluated using part-per-million concentrations of hydrogen, helium, oxygen and argon mixed into a nitrogen gas stream. Relative accuracy and precision when quantitating the four analytes were better than the NASA-required minimum of 10% error and 5% deviation, respectively. Limits of detection were below the NASA requirement of 25-ppm hydrogen and 100-ppm helium; those for oxygen and argon were slightly higher than the requirement. The instrument provided adequate performance at fast data recording rates, demonstrating the utility of an ion trap mass spectrometer as a real-time quantitative monitoring device for permanent gas analysis.

  11. New permanent magnets; manganese compounds.

    Science.gov (United States)

    Coey, J M D

    2014-02-12

    The exponential growth of maximum energy product that prevailed in the 20th century has stalled, leaving a market dominated by two permanent magnet materials, Nd2Fe14B and Ba(Sr)Fe12O19, for which the maximum theoretical energy products differ by an order of magnitude (515 kJ m(-3) and 45 kJ m(-3), respectively). Rather than seeking to improve on optimized Nd-Fe-B, it is suggested that some research efforts should be devoted to developing appropriately priced alternatives with energy products in the range 100-300 kJ m(-3). The prospects for Mn-based hard magnetic materials are discussed, based on known Mn-based compounds with the tetragonal L10 or D022 structure or the hexagonal B81 structure.

  12. CHALLENGES OF PERMANENT TEACHER TRAINING

    Directory of Open Access Journals (Sweden)

    María Manuela Valles-Ornelas

    2015-07-01

    Full Text Available The new challenges for teachers and managers require to assume permanent formation as a tool for responding effectively and efficiently to them, different perspective to strengthen from the initial teacher education programs. The research was done in a primary school in the state of Chihuahua. The method used was research action, the question was: How can we encourage the lifelong learning and training of the staff of this school, with the purpose to assist them in these processes to improve the service that the school provides to students. The school group is the center of the process, the cooperative and collaborative work accompanied by educational leadership and persuasive provide better results, and all accompanied by the professional selfinvitation.

  13. Bose-Einstein Condensation in an electro-pneumatically transformed quadrupole-Ioffe magnetic trap

    CERN Document Server

    Kumar, Sunil; Verma, Gunjan; Vishwakarma, Chetan; Noaman, Md; Rapol, Umakant

    2014-01-01

    We report a novel approach for preparing a Bose-Einstein condensate (BEC) of $^{87}$Rb atoms using electro-pneumatically driven transfer of atoms into a Quadrupole-Ioffe magnetic trap (QUIC Trap). More than 5$\\times$$10^{8}$ atoms from a Magneto-optical trap are loaded into a spherical quadrupole trap and then these atoms are transferred into an Ioffe trap by moving the Ioffe coil towards the center of the quadrupole coil, thereby, changing the distance between quadrupole trap center and the Ioffe coil. The transfer efficiency is more than 80 \\%. This approach is different from a conventional approach of loading the atoms into a QUIC trap wherein the spherical quadrupole trap is transformed into a QUIC trap by changing the currents in the quadrupole and the Ioffe coils. The phase space density is then increased by forced rf evaporative cooling to achieve the Bose-Einstein condensation having more than $10^{5}$ atoms.

  14. Testing of Nb3Sn quadrupole coils using magnetic mirror structure

    Energy Technology Data Exchange (ETDEWEB)

    Zlobin, A.V.; Andreev, N.; Barzi, E.; Bossert, R.; Chlachidze, G.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.; Novitski, I.; Tartaglia, M.; Tompkins, J.C.; /Fermilab

    2009-07-01

    This paper describes the design and parameters of a quadrupole mirror structure for testing the mechanical, thermal and quench performance of single shell-type superconducting quadrupole coils at field, current and force levels similar to that of real magnet. The concept was experimentally verified by testing two quadrupole coils, previously used in quadrupole models, in the developed mirror structure in the temperature range from 4.5 to 1.9 K. The coils were instrumented with voltage taps, heaters, and strain gauges to monitor their mechanical and thermal properties and quench performance. A new quadrupole coil made of improved Nb{sub 3}Sn RRP-108/127 strand and cable insulation based on E-glass tape was also tested using this structure. The fabrication and test results of the quadrupole mirror models are reported and discussed.

  15. Testing of Nb3Sn quadrupole coils using magnetic mirror structure

    Energy Technology Data Exchange (ETDEWEB)

    Zlobin, A.V.; Andreev, N.; Barzi, E.; Bossert, R.; Chlachidze, G.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.; Novitski, I.; Tartaglia, M.; Tompkins, J.C.; /Fermilab

    2009-07-01

    This paper describes the design and parameters of a quadrupole mirror structure for testing the mechanical, thermal and quench performance of single shell-type superconducting quadrupole coils at field, current and force levels similar to that of real magnet. The concept was experimentally verified by testing two quadrupole coils, previously used in quadrupole models, in the developed mirror structure in the temperature range from 4.5 to 1.9 K. The coils were instrumented with voltage taps, heaters, and strain gauges to monitor their mechanical and thermal properties and quench performance. A new quadrupole coil made of improved Nb{sub 3}Sn RRP-108/127 strand and cable insulation based on E-glass tape was also tested using this structure. The fabrication and test results of the quadrupole mirror models are reported and discussed.

  16. Design, simulation and construction of quadrupole magnets for focusing electron beam in powerful industrial electron accelerator

    Directory of Open Access Journals (Sweden)

    S KH Mousavi

    2015-09-01

    Full Text Available In this paper the design and simulation of quadrupole magnets and electron beam optical of that by CST Studio code has been studied. Based on simulation result the magnetic quadrupole has been done for using in beam line of first Iranian powerful electron accelerator. For making the suitable magnetic field the effects of material and core geometry and coils current variation on quadrupole magnetic field have been studied. For test of quadrupole magnet the 10 MeV beam energy and 0.5 pi mm mrad emittance of input beam has been considered. We see the electron beam through the quadrupole magnet focus in one side and defocus in other side. The optimum of distance between two quadrupole magnets for low emittance have been achieved. The simulation results have good agreement with experimental results

  17. Intrusive luxation of 60 permanent incisors

    DEFF Research Database (Denmark)

    Tsilingaridis, Georgios; Malmgren, Barbro; Andreasen, Jens O;

    2012-01-01

      Intrusive luxation in the permanent dentition is an uncommon injury but it is considered one of the most severe types of dental trauma because of the risk for damage to the periodontal ligament, pulp and alveolar bone. Management of intrusive luxation in the permanent dentition is controversial....... The purpose of this study was to evaluate pulp survival and periodontal healing in intrusive luxated permanent teeth in relation to treatment alternatives, degree of intrusion and root development....

  18. Dental Interventions on First Permanent Molars

    OpenAIRE

    2016-01-01

    The first permanent molars have the biggest dental morbidity and mortality of all permanent teeth. The main aim was to evaluate of the most common dental problems and procedures that are performed on the first permanent molars. Material and method: examination was performed in three private dental offices, two from urban and one from rural region, over a period of 2 years. The data was obtained by using dental charts from the patients and by the ambulatory register for performe...

  19. Improvement of levitation force characteristics in magnetic levitation type seismic isolation device composed of HTS bulk and permanent magnet

    Science.gov (United States)

    Tsuda, M.; Kawasaki, T.; Yagai, T.; Hamajima, T.

    2008-02-01

    Magnetic levitation type seismic isolation device composed of HTS bulks and permanent magnets can theoretically remove horizontal vibration completely. It is, however, not easy to generate the large levitation force by using only the levitation system composed of HTS bulk and permanent magnet (HTS-PM system). We focused on a hybrid levitation system composed of the HTS-PM system and the PM-PM system composed of only permanent magnets and investigated the suitable arranging method of the hybrid system for improving levitation force and obtaining stable levitation. In order to clarify the most suitable permanent magnet arrangement in the PM-PM system for the levitation force improvement, repulsive force between permanent magnets was measured in various kinds of the PM-PM system. The maximum repulsive force per unit area in the PM-PM system was at least three times larger than the levitation force per unit area in the HTS-PM system, so that the levitation force in the hybrid system was larger than that of the HTS-PM system. Stable levitation was also achieved in the hybrid system. This is because repulsive force in the PM-PM system against horizontal displacement was much smaller than restoring force in the HTS-PM system.

  20. Permanence of Stochastic Lotka-Volterra Systems

    Science.gov (United States)

    Liu, Meng; Fan, Meng

    2017-04-01

    This paper proposes a new definition of permanence for stochastic population models, which overcomes some limitations and deficiency of the existing ones. Then, we explore the permanence of two-dimensional stochastic Lotka-Volterra systems in a general setting, which models several different interactions between two species such as cooperation, competition, and predation. Sharp sufficient criteria are established with the help of the Lyapunov direct method and some new techniques. This study reveals that the stochastic noises play an essential role in the permanence and characterize the systems being permanent or not.

  1. Quadrupole Moments of Rapidly Rotating Compact Objects in Dilatonic Einstein-Gauss-Bonnet Theory

    CERN Document Server

    Kleihaus, Burkhard; Mojica, Sindy

    2014-01-01

    We consider rapidly rotating black holes and neutron stars in dilatonic Einstein-Gauss-Bonnet (EGBd) theory and determine their quadrupole moments, which receive a contribution from the dilaton. The quadrupole moment of EGBd black holes can be considerably larger than the Kerr value. For neutron stars, the universality property of the $\\hat I$-$\\hat Q$ relation between the scaled moment of inertia and the scaled quadrupole moment appears to extend to EGBd theory.

  2. Precision Alignments of Stripline BPMs with Quadrupole Magnets for TTF2

    CERN Document Server

    Priebe, G; Wendt, M; Werner, M

    2004-01-01

    We report on our alignment setup to calibrate beam position monitors (BPM) with respect to the magnetic axis of the quadrupole magnets used in the warm sections of the TESLA Test Facility (TTF2). The Stripline BPM's are fixed inside the quadrupole magnets. A streched wire measurement was used to calibrate the electrical axis of the BPM wrt. to the magnetic axis of the quadrupole.

  3. Progress in the Development of Superconducting Quadrupoles forHeavy-ion Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, R.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-08-19

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  4. Progress in the development of superconducting quadrupoles for heavy ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, B.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-05-24

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  5. Measurement, analysis and modification of the fifth-order fringe field components of magnetic quadrupole lenses

    Energy Technology Data Exchange (ETDEWEB)

    Moloney, G.R.; Jamieson, D.N.; Legge, G.J.F. (School of Physics, Univ. of Melbourne, Parkville (Australia))

    1991-03-01

    Extensive, quantitative measurements of magnetic quadrupole lens fringe fields have been conducted. The fringe field region of magnetic quadrupole lenses has been shown to contain significant contamination by higher-order multipole fields. These multipole components will contribute to the aberration coefficients of the lens. One of the largest components is the duodecapole component, which contributes to the fifth-order geometric aberrations of the lens. The measured multipole profiles in the fringe field region of the Melbourne quadrupoles are presented. We also present the results of an investigation into the effect of modifying the quadrupole pole tip profile at the pole ends. (orig.).

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

    Science.gov (United States)

    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.

  7. Small Aperture BPM to Quadrupole Assembly Tolerance Study

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Superconducting focusing quadrupoles for heavy ion fusion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Sabbi, G.L.; Faltens, A.; Leitner, M.; Lietzke, A.; Seidl, P.; Barnard, J.; Lund, S.; Martovetsky, N.; Gung, C.; Minervini, J.; Radovinsky, A.; Schultz, J.; Meinke, R.

    2003-05-01

    The Heavy Ion Fusion (HIF) Program is developing superconducting focusing magnets for both near-term experiments and future driver accelerators. In particular, single bore quadrupoles have been fabricated and tested for use in the High Current Experiment (HCX) at Lawrence Berkeley National Laboratory (LBNL). The next steps involve the development of magnets for the planned Integrated Beam Experiment (IBX) and the fabrication of the first prototype multi-beam focusing arrays for fusion driver accelerators. The status of the magnet R&D program is reported, including experimental requirements, design issues and test results.

  9. Optimized Superconducting Quadrupole Arrays for Multiple Beam Transport

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Status of the LHC inner triplet quadrupole program at Fermilab

    CERN Document Server

    Andreev, N; Bauer, P; Bossert, R; Brandt, J; Carson, J; Caspi, S; Chichili, D R; Chiesa, L; Darve, C; Di Marco, J; Fehér, S; Ghosh, A; Glass, H; Huang, Y; Kerby, J S; Lamm, M J; Markarov, A A; McInturff, A D; Nicol, T H; Nobrega, A; Novitski, I; Ogitsu, T; Orris, D; Ozelis, J P; Page, T; Peterson, T; Rabehl, Roger Jon; Robotham, W; Sabbi, G L; Scanlan, R M; Schlabach, P; Sylvester, C D; Strait, J B; Tartaglia, M; Tompkins, J C; Velev, G V; Yadav, S; Zlobin, A V

    2001-01-01

    Fermilab, in collaboration with LBNL and BNL, is developing a quadrupole for installation in the interaction region inner triplets of the LHC. This magnet is required to have an operating gradient of 215 T/m across a 70 mm coil bore, and operates in superfluid helium at 1.9 K. A 2 m magnet program addressing mechanical, magnetic, quench protection, and thermal issues associated with the design was completed earlier this year, and production of the first full length, cryostatted prototype magnet is underway. This paper summarizes the conclusions of the 2 m program, and the design and status of the first full-length prototype magnet. (11 refs).

  11. Beam acceleration through proton radio frequency quadrupole accelerator in BARC

    Science.gov (United States)

    Bhagwat, P. V.; Krishnagopal, S.; Mathew, J. V.; Singh, S. K.; Jain, P.; Rao, S. V. L. S.; Pande, M.; Kumar, R.; Roychowdhury, P.; Kelwani, H.; Rama Rao, B. V.; Gupta, S. K.; Agarwal, A.; Kukreti, B. M.; Singh, P.

    2016-05-01

    A 3 MeV proton Radio Frequency Quadrupole (RFQ) accelerator has been designed at the Bhabha Atomic Research Centre, Mumbai, India, for the Low Energy High Intensity Proton Accelerator (LEHIPA) programme. The 352 MHz RFQ is built in 4 segments and in the first phase two segments of the LEHIPA RFQ were commissioned, accelerating a 50 keV, 1 mA pulsed proton beam from the ion source, to an energy of 1.24 MeV. The successful operation of the RFQ gave confidence in the physics understanding and technology development that have been achieved, and indicate that the road forward can now be traversed rather more quickly.

  12. Kick velocity induced by magnetic dipole and quadrupole radiation

    CERN Document Server

    Kojima, Yasufumi

    2010-01-01

    We examine the recoil velocity induced by the superposition of the magnetic dipole and quadrupole radiation from a pulsar/magnetar born with rapid rotation. The resultant velocity depends on not the magnitude, but rather the ratio of the two moments and their geometrical configuration. The model does not necessarily lead to high spatial velocity for a magnetar with a strong magnetic field, which is consistent with the recent observational upper bound. The maximum velocity predicted with this model is slightly smaller than that of observed fast-moving pulsars.

  13. 2-MV electrostatic quadrupole injector for heavy-ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Bieniosek, F.M.; Celata, C.M.; Henestroza, E.; Kwan, J.W.; Prost, L.; Seidl, P.A.

    2004-11-10

    High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole (ESQ) injector is capable of providing these high charge density and low emittance beams. We have modified the existing 2-MV Injector to reduce beam emittance and to double the pulse length. We characterize the beam delivered by the modified injector to the High Current Transport Experiment (HCX) and the effects of finite rise time of the extraction voltage pulse in the diode on the beam head. We demonstrate techniques for mitigating aberrations and reducing beam emittance growth in the injector.

  14. Quadrupole collectivity in Si isotopes around N=20

    CERN Document Server

    Rodríguez-Guzman, R R; Robledo, L M

    2001-01-01

    The angular momentum projected Generator Coordinate Method using the quadrupole moment as collective coordinate and the Gogny force as the effective interaction is used to describe the properties of the ground state and low-lying excited states of the neutron rich light nuclei 32,34,36Si. It is found that the ground state of the nucleus 34Si is spherical. However, this is not only due to the N=20 shell closure as the ground state of 34Si contains a significant amount of the intruder f7/2 neutron orbital. On the other hand, rather good agreement with experimental data for many observables is obtained.

  15. Electrostatic quadrupole accelerator for the heavy ion fusion project

    Energy Technology Data Exchange (ETDEWEB)

    Henestroza, E.; Yu, S.; Eylon, S.

    1994-07-01

    A full scale (2 MeV, 800 mA, K{sup +}), low emittance injector for the Heavy Ion Fusion Project has been built at LBL It consists of a 750 key diode pre-injector followed by an electrostatic quadrupole accelerator (ESQ) which provide strong (alternating gradient) focusing for the space-charge dominated beam and simultaneously accelerates the ions to 2 MeV. The actual operation of this new machine has exceeded design parameters. Design of the accelerator, report on experiments performed in connection with the evaluation and characterization of the ESQ and corresponding 3D Particle in Cell simulations will be presented.

  16. Low-lying quadrupole collectivity in {sup 136}Xe

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Christian; Leske, Joerg; Pietralla, Norbert; Reese, Michael [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany); Bazzacco, Dino; Farnea, Enrico [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Gadea, Andres [Instituto de Fisica Corpuscular, CSIC-Universitat de Valencia, Valencia (Spain); Gottardo, Andrea [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy); Dipartimento di Fisica e Astronomia dell' Universita degli Studi di Padova, Padova (Italy); John, Philipp Rudolf; Michelagnoli, Caterina [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Dipartimento di Fisica e Astronomia dell' Universita degli Studi di Padova, Padova (Italy); Valiente-Dobon, Jose Javier [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy)

    2015-07-01

    We present recent results from our investigation of low-lying quadrupole collectivity in the semi-magic N=82 nucleus {sup 136}Xe. An experiment was performed at the Legnaro National Laboratory employing the AGATA demonstrator. Level-lifetimes and B(E2, 0{sup +}{sub 1}→2{sup +}{sub i})-values were determined from Coulomb excitation and by the continuous-angle DSA method exploiting AGATA's position resolution. 2{sup +}{sub i} - states up to i=7 were excited and analyzed.

  17. Nuclear quadrupole resonance of boron in borate glasses

    Science.gov (United States)

    Gravina, Samuel J.; Bray, Phillip J.

    A continuous wave nuclear quadrupole resonance spectrometer that has a high sensitivity even at low frequencies has been built. Boron and aluminum NQR has been detected in the region 200 kHz to 1.4 MHz. For the first time, boron NQR has been detected in a glass. The NQR spectrum of pure B 20 3 glass is consistent with 85 ± 2% of the boron atoms belonging to boroxol rings. In sodium borate glasses, the number of borons in boroxol rings decreases with increasing sodium content, until when sodium oxide comprises 20 mol% of the glass less than 2% of the borons are in boroxol rings.

  18. Underpinning hybridization intuition for complex nanoantennas by magnetoelectric quadrupolar polarizability retrieval

    NARCIS (Netherlands)

    Bernal Arango, F.; Coenen, T.; Koenderink, A.F.

    2014-01-01

    A central idea in plasmonics and metamaterials is to interpret scattering resonances as resulting from hybridization of electric dipoles. Recent developments in metamaterials as well as in plasmonic Fano systems have further included magnetic dipoles and electric quadrupoles in this reasoning. We

  19. Hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    West, J.G.W. [Electrical Machines (United Kingdom)

    1997-07-01

    The reasons for adopting hybrid vehicles result mainly from the lack of adequate range from electric vehicles at an acceptable cost. Hybrids can offer significant improvements in emissions and fuel economy. Series and parallel hybrids are compared. A combination of series and parallel operation would be the ideal. This can be obtained using a planetary gearbox as a power split device allowing a small generator to transfer power to the propulsion motor giving the effect of a CVT. It allows the engine to run at semi-constant speed giving better fuel economy and reduced emissions. Hybrid car developments are described that show the wide range of possible hybrid systems. (author)

  20. 22 CFR 401.3 - Permanent offices.

    Science.gov (United States)

    2010-04-01

    ... Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.3 Permanent offices. The permanent offices of the Commission shall be at Washington, in the District of... of the Commission shall have full charge and control of said offices, respectively....

  1. resonant inverter supplied interior permanent magnet (ipm)

    African Journals Online (AJOL)

    user

    Permanent Magnet (IPM) or Surface Permanent. Magnet ... desired torque is produced to rotate the motor in the desired ... u axis, and the direct-axis of the rotor is at angle θ from the ..... Based Stator Flux Estimator” International. Journal of ...

  2. Comparison of adjustable permanent magnetic field sources

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Bahl, Christian Robert Haffenden; Smith, Anders

    2010-01-01

    A permanent magnet assembly in which the flux density can be altered by a mechanical operation is often significantly smaller than comparable electromagnets and also requires no electrical power to operate. In this paper five permanent magnet designs in which the magnetic flux density can...

  3. Magnetic guns with cylindrical permanent magnets

    DEFF Research Database (Denmark)

    Vokoun, David; Beleggia, Marco; Heller, Luděk

    2012-01-01

    The motion of a cylindrical permanent magnet (projectile) inside a tubular permanent magnet, with both magnets magnetized axially, illustrates nicely the physical principles behind the operation of magnetic guns. The force acting upon the projectile is expressed semi-analytically as derivative...

  4. Leadership in a (permanent) crisis.

    Science.gov (United States)

    Heifetz, Ronald; Grashow, Alexander; Linsky, Marty

    2009-01-01

    The current economic crisis is not just another rough spell. Today's mix of urgency, high stakes, and uncertainty will continue even after the recession ends. The immediate crisis--which we will get through with policy makers' expert technical adjustments--sets the stage for a sustained, or even permanent, crisis, a relentless series of challenges no one has encountered before. Instead of hunkering down and relying on their familiar expertise to deal with the sustained crisis, people in positions of authority--whether they are CEOs or managers heading up a company initiative--must practice what the authors call adaptive leadership. They must, of course, tackle the underlying causes of the crisis, but they must also simultaneously make the changes that will allow their organizations to thrive in turbulent environments. Adaptive leadership is an improvisational and experimental art, requiring some new practices. Like Julie Gilbert, who overcame internal resistance to reorient Best Buy toward female purchasers, adaptive leaders get things done to meet today's challenges and then modify those things to thrive in tomorrow's world. They also embrace disequilibrium, using turbulence as an opportunity to build crucial new capacities, as Paul Levy did to rescue Beth Israel Deaconess Medical Center from a profound financial crisis. Finally, adaptive leaders, such as Egon Zehnder, the founder of an executive search firm, draw out the leadership skills that reside deep in the organization, recognizing the interdependence of all employees and mobilizing everyone to generate solutions.

  5. Finite element modeling of permanent magnet devices

    Science.gov (United States)

    Brauer, J. R.; Larkin, L. A.; Overbye, V. D.

    1984-03-01

    New techniques are presented for finite element modeling of permanent magnets in magnetic devices such as motors and generators. These techniques extend a previous sheet-current permanent magnet model that applies only for straight line B-H loops and rectangular-shaped magnets. Here Maxwell's equations are used to derive the model of a permanent magnet having a general curved B-H loop and any geometric shape. The model enables a nonlinear magnetic finite element program to use Newton-Raphson iteration to solve for saturable magnetic fields in a wide variety of devices containing permanent magnets and steels. The techniques are applied to a brushless dc motor with irregular-shaped permanent magnets. The calculated motor torque agrees well with measured torque.

  6. Gating of Permanent Molds for ALuminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-03-30

    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  7. Enhancement of Low Voltage Ride Through Ability of Permanent Magnet Synchronous Wind Power Generation Sets Based on Hybrid Energy Storage System Composed of Vanadium Redox Battery and Super Capacitor%基于钒电池-超级电容混合储能技术的永磁同步风电机组低电压穿越能力提升研究

    Institute of Scientific and Technical Information of China (English)

    任永峰; 彭伟; 刘海涛; 薛宇; 周杰; 安中全

    2014-01-01

    以基于双三电平变流器的2 MW直驱式永磁同步风力机组低电压穿越为研究对象,机侧变流器采用最大转矩电流比控制,对网侧变流器提出了新颖的稳态时单位功率因数控制、电网暂态故障时无功优先、有功受限协调控制策略。对全钒液流电池和超级电容进行等效电路模型分析,采用双向DC/DC 变换电路作为混合储能系统和风力机组直流母线的接口,并定量模拟电网电压单相、三相深度跌落,对机组采用直流母线卸荷电路、改进控制策略以及混合储能方式实现低电压穿越进行了对比仿真。研究结果很好地说明:上述3种方案在严重的电网电压跌落情况下均可实现风电机组低电压穿越,钒电池-超级电容混合储能方式可以更好地提升机组低电压穿越能力,并加速系统有功恢复过程。%The low voltage ride through (LVRT) of dual tri-level converter based direct-driven permanent magnet synchronous wind power generation set with rated capacity of 2MW is taken as the research object. The converter at the generator side is controlled by dual closed-loop based maximum peak torque to current ratio, and for the converter at the grid side a novel control strategy, in which the unity power factor control is applied during steady state and the coordinated control of reactive power prioritized with active power restricted is applied during grid transient fault, is put forward. The analysis on equivalent models of vanadium redox battery (VRB) and super capacitor are performed, and taking dual-directional DC/DC conversion circuit as the interface for the hybrid energy storage system and the DC bus of wind power generation unit the symmetrical and unsymmetrical deep voltage sags are quantitatively simulated, and the contrastive simulation of the implementation of LVRT ability of generation units by adopting the DC bus unloading circuit, the improved control strategies and the

  8. Performance of a Nb(3)Sn Quadrupole Under High Stress

    CERN Document Server

    Felice, H; Ferracin, P; De Rijk, G; Bajko, M; Caspi, S; Bingham, B; Giloux, C; Bordini, B; Milanese, A; Bottura, L; Sabbi, G L; Hafalia, R; Godeke, A; Dietderich, D

    2011-01-01

    Future upgrades of the Large Hadron Collider (LHC) will require large aperture and high gradient quadrupoles. Nb(3)Sn is the most viable option for this application but is also known for its strain sensitivity. In high field magnets, with magnetic fields above 12 T, the Lorentz forces will generate mechanical stresses that may exceed 200 MPa in the windings. The existing measurements of critical current versus strain of Nb(3)Sn strands or cables are not easily applicable to magnets. In order to investigate the impact of high mechanical stress on the quench performance, a series of tests was carried out within a LBNL/CERN collaboration using the magnet TQS03 (a LHC Accelerator Research Program (LARP) 1-meter long, 90-mm aperture Nb(3)Sn quadrupole). The magnet was tested four times at CERN under various pre-stress conditions. The average mechanical compressive azimuthal pre-stress on the coil at 4.2 K ranged from 120 MPa to 200 MPa. This paper reports on the magnet performance during the four tests focusing on...

  9. Chaotic motion in axially symmetric potentials with oblate quadrupole deformation

    Energy Technology Data Exchange (ETDEWEB)

    Letelier, Patricio S. [Departamento de Matematica Aplicada, IMECC, Universidade Estadual de Campinas, 13083-859, Campinas, SP (Brazil); Ramos-Caro, Javier, E-mail: javier@ime.unicamp.br [Departamento de Matematica Aplicada, IMECC, Universidade Estadual de Campinas, 13083-859, Campinas, SP (Brazil); Lopez-Suspes, Framsol, E-mail: framsol@gmail.com [Facultad de Telecomunicaciones, Universidad Santo Tomas and Escuela de Fisica, Universidad Industrial de Santander, Bucaramanga (Colombia)

    2011-10-03

    By computing the Poincare's surfaces of section and Lyapunov exponents, we study the effect of introducing an oblate quadrupole in the dynamics associated with two generic spherical potentials of physical interest: the central monopole and the isotropic harmonic oscillator. In the former case we find saddle points in the effective potential, in contrast to the statements presented by Gueron and Letelier in [E. Gueron, P.S. Letelier, Phys. Rev. E 63 (2001) 035201]. The results we show in the second case have application in nuclear or atomic physics. In particular, we find values of oblate deformation leading to a disappearance of shell structure in the single-particle spectrum. -- Highlights: → We find chaotic motion around a monopole with oblate quadrupole deformation. → This corrects the statements introduced in [E. Gueron, P.S. Letelier, Phys. Rev. E 63 (2001) 035201]. → We present an alternative model for the potential due to an oblate deformed nuclei. → This leads to stochastic regions in the phase space of classical orbits. → It suggests that the shell structure of single-particle spectrum tends to disappear.

  10. VIBRATION MEASUREMENTS IN A RHIC QUADRUPOLE AT CRYOGENIC TEMPERATURES.

    Energy Technology Data Exchange (ETDEWEB)

    JAIN, A.; AYDIN, S.; HE, P.; ANERELLA, M.; GANETIS, G.; HARRISON, M.; PARKER, B.; PLATE, S.

    2005-10-17

    One of the concerns in using compact superconducting magnets in the final focus region of the ILC is the influence of the cryogen flow on the vibration characteristics. As a first step towards characterizing such motion at nanometer levels, a project was undertaken at BNL to measure the vibrations in a spare RHIC quadrupole under cryogenic conditions. Given the constraints of cryogenic operation, and limited space available, it was decided to use a dual head laser Doppler vibrometer for this work. The performance of the laser vibrometer was tested in a series of room temperature tests and compared with results from Mark L4 geophones. The laser system was then used to measure the vibration of the cold mass of the quadrupole with respect to the outside warm enclosure. These measurements were carried out both with and without the flow of cold helium through the magnet. The results indicate only a minor increase in motion in the horizontal direction (where the cold mass is relatively free to move).

  11. Extracting the Omega- electric quadrupole moment from lattice QCD data

    CERN Document Server

    Ramalho, G

    2010-01-01

    The Omega- has an extremely long lifetime, and is the most stable of the baryons with spin 3/2. Therefore the Omega- magnetic moment is very accurately known. Nevertheless, its electric quadrupole moment was never measured, although estimates exist in different formalisms. In principle, lattice QCD simulations provide at present the most appropriate way to estimate the Omega- form factors, as function of the square of the transferred four-momentum, Q2, since it describes baryon systems at the physical mass for the strange quark. However, lattice QCD form factors, and in particular GE2, are determined at finite Q2 only, and the extraction of the electric quadrupole moment, Q_Omega= GE2(0) e/(2 M_Omega), involves an extrapolation of the numerical lattice results. In this work we reproduce the lattice QCD data with a covariant spectator quark model for Omega- which includes a mixture of S and two D states for the relative quark-diquark motion. Once the model is calibrated, it is used to determine Q_Omega. Our pr...

  12. Busbar studies for the LHC interaction region quadrupoles

    CERN Document Server

    Bauer, P; Fehér, S; Kerby, J S; Lamm, M J; Orris, D; Sylvester, C D; Tompkins, J C; Zlobin, A V

    2001-01-01

    Fermilab (FNAL) and the Japanese high energy physics lab (KEK) are developing the superconducting quadrupole magnets for the interaction regions (IR) of the Large Hadron Collider (LHC). These magnets have a nominal field gradient of 215 T/m in a 70 mm bore and operate in superfluid helium at 1.9 K. The IR magnets are electrically interconnected with superconducting busbars, which need to be protected in the event of a quench. Experiments to determine the most suitable busbar design for the LHC IR magnets and the analysis of the data are presented. The main purpose of the study was to find a design that allows the inclusion of the superconducting busbars in the magnet quench protection scheme, thus avoiding additional quench protection circuitry. A proposed busbar design that was tested in these experiments consists of a superconducting cable, which is normally used for the inner layer of the Fermilab IR quadrupoles, soldered to similar Rutherford type cables as a stabilizer. A series of prototypes with varyin...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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 are traditionally 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.

  15. Extracting the Omega- electric quadrupole moment from lattice QCD data

    Energy Technology Data Exchange (ETDEWEB)

    G. Ramalho, M.T. Pena

    2011-03-01

    The Omega- has an extremely long lifetime, and is the most stable of the baryons with spin 3/2. Therefore the Omega- magnetic moment is very accurately known. Nevertheless, its electric quadrupole moment was never measured, although estimates exist in different formalisms. In principle, lattice QCD simulations provide at present the most appropriate way to estimate the Omega- form factors, as function of the square of the transferred four-momentum, Q2, since it describes baryon systems at the physical mass for the strange quark. However, lattice QCD form factors, and in particular GE2, are determined at finite Q2 only, and the extraction of the electric quadrupole moment, Q_Omega= GE2(0) e/(2 M_Omega), involves an extrapolation of the numerical lattice results. In this work we reproduce the lattice QCD data with a covariant spectator quark model for Omega- which includes a mixture of S and two D states for the relative quark-diquark motion. Once the model is calibrated, it is used to determine Q_Omega. Our prediction is Q_Omega= (0.96 +/- 0.02)*10^(-2) efm2 [GE2(0)=0.680 +/- 0.012].

  16. Hybrid Quadrupole-Orbitrap mass spectrometry for quantitative measurement of quorum sensing inhibition.

    Science.gov (United States)

    Todd, Daniel A; Zich, David B; Ettefagh, Keivan A; Kavanaugh, Jeffrey S; Horswill, Alexander R; Cech, Nadja B

    2016-08-01

    Drug resistant bacterial infections cause significant morbidity and mortality worldwide, and new strategies are needed for the treatment of these infections. The anti-virulence approach, which targets non-essential virulence factors in bacteria, has been proposed as one way to combat the problem of antibiotic resistance. Virulence in methicillin-resistant Staphylococcus aureus (MRSA) and many other Gram-positive bacterial pathogens is controlled by the quorum sensing system. Thus, there is excellent therapeutic potential for compounds that target this system. With this project, we have developed and validated a novel approach for measuring quorum sensing inhibition in vitro. Ultraperformance liquid chromatography coupled to mass spectrometry (UPLC-MS) was employed to directly measure one of the important outputs of the quorum sensing system in MRSA, auto-inducing peptide I (AIP I) in bacterial cultures. The method for AIP detection was validated and demonstrated limits of detection and quantification of range of 0.0035μM and 0.10μM, respectively. It was shown that the known quorum sensing inhibitor ambuic acid inhibited AIP I production by a clinically relevant strain of MRSA, with an IC50 value of 2.6±0.2μM. The new method performed similarly to previously published methods using GFP reporter assays, but has the advantage of being applicable without the need for engineering of a reporter strain. Additionally, the mass spectrometry-based method could be applicable in situations where interference by the inhibitor prevents the application of fluorescence-based methods.

  17. Cluster SIMS with a hybrid quadrupole time-of-flight mass spectrometer

    Science.gov (United States)

    Carado, A.; Kozole, J.; Passarelli, M.; Winograd, N.; Loboda, A.; Wingate, J.

    2008-12-01

    The new physics associated with cluster SIMS, i.e. reduced chemical damage enabling 3D dynamic imaging, and increased ion yields from organics samples, suggests that cluster sources may be suitable for use on commercial MALDI/electrospray (ESI) instruments. In efforts to investigate this approach to secondary ion analysis, a 20 keV C 60+ primary ion source by Ionoptika Ltd. was fitted to a commercial LC/MS/MS instrument; the QSTAR ® XL system by Applied Biosystems/MDS Sciex. This instrument is capable of MS/MS, ion trapping, chemical imaging, and utilizes an orthogonal ToF, enabling use of a DC primary ion beam for imaging and data collection. The system employs high nitrogen pressure, typically several millitorr, in the sample region, as opposed to large extraction voltages, to facilitate the transmission of the secondary ions to the ToF region. In these initial experiments, it was demonstrated that ion signal generated by C 60+ bombardment can be enhanced by trapping in the collision cell and that secondary ions can fragment via collision induced dissociation (CID) to yield MS/MS information. In ToF-MS mode, efficiencies are comparable with pulsed primary beam ToF-SIMS instruments. Mass resolution of over 12,000 is routinely observed with mass accuracy in the 2 ppm range, which has important implications in accurate ion mapping in imaging mode.

  18. Cluster SIMS with a hybrid quadrupole time-of-flight mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Carado, A. [Pennsylvania State University, 104 Chemistry Building, University Park, PA 16802 (United States)], E-mail: ajc161@psu.edu; Kozole, J.; Passarelli, M.; Winograd, N. [Pennsylvania State University, 104 Chemistry Building, University Park, PA 16802 (United States); Loboda, A.; Wingate, J. [Applied Biosystems/MDS Sciex, 71 Four Valley Drive, Concord, Ontario, CA (United States)

    2008-12-15

    The new physics associated with cluster SIMS, i.e. reduced chemical damage enabling 3D dynamic imaging, and increased ion yields from organics samples, suggests that cluster sources may be suitable for use on commercial MALDI/electrospray (ESI) instruments. In efforts to investigate this approach to secondary ion analysis, a 20 keV C{sub 60}{sup +} primary ion source by Ionoptika Ltd. was fitted to a commercial LC/MS/MS instrument; the QSTAR XL system by Applied Biosystems/MDS Sciex. This instrument is capable of MS/MS, ion trapping, chemical imaging, and utilizes an orthogonal ToF, enabling use of a DC primary ion beam for imaging and data collection. The system employs high nitrogen pressure, typically several millitorr, in the sample region, as opposed to large extraction voltages, to facilitate the transmission of the secondary ions to the ToF region. In these initial experiments, it was demonstrated that ion signal generated by C{sub 60}{sup +} bombardment can be enhanced by trapping in the collision cell and that secondary ions can fragment via collision induced dissociation (CID) to yield MS/MS information. In ToF-MS mode, efficiencies are comparable with pulsed primary beam ToF-SIMS instruments. Mass resolution of over 12,000 is routinely observed with mass accuracy in the 2 ppm range, which has important implications in accurate ion mapping in imaging mode.

  19. Biological tissue imaging with a hybrid cluster SIMS quadrupole time-of-flight mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Carado, A. [Pennsylvania State University, 104 Chemistry Building, University Park, PA (United States)], E-mail: ajc161@psu.edu; Kozole, J.; Passarelli, M.; Winograd, N. [Pennsylvania State University, 104 Chemistry Building, University Park, PA (United States); Loboda, A. [Applied Biosystems/MDS Sciex, 71 Four Valley Drive, Concord, Ontario, CA (United States); Bunch, J. [Centre for Analytical Sciences, University of Sheffield, Sheffield S3 7HF (United Kingdom); Wingate, J. [Applied Biosystems/MDS Sciex, 71 Four Valley Drive, Concord, Ontario, CA (United States); Hankin, J.; Murphy, R. [University of Colorado at Denver and Health Science Center, 12801 East 17th Avenue, Aurora, CO (United States)

    2008-12-15

    A 20 keV C{sub 60}{sup +} ion source was mounted onto a commercial MALDI/electrospray orthogonal ToF mass spectrometer. Cross-sectional mouse brain and lung slices between 5 and 10 {mu}m prepared by cryostat sectioning were successfully imaged using a DC C{sub 60}{sup +} primary ion beam at a spot size of 100 {mu}m. Analysis was performed at room temperature following vacuum drying. An abundance of ions were mapped in all samples, many whose identity can only be found using the MS/MS functionality. We have successfully identified and imaged localizations of diacylglycerol (DAG) ions - 1-palmitoyl-2-oleoyl-glycerol (m/z{sup +} 577.5) and 1,2-dioleoyl-glycerol (m/z{sup +} 603.5) - in lung tissue. The mouse brain slice revealed strong, distinct localizations of many ions revealing the potential for this technique for biological imaging. Ions throughout the mass range of m/z{sup +} 50-800 were collected in sufficient quantities to permit unambiguous chemical mapping. Mass resolutions of 12,000 or greater were routinely obtained allowing for more accurate ion mapping than typically seen with ToF-SIMS image analysis.

  20. Development and testing of the improved focusing quadrupole for heavy ion fusion accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Manahan, R R; Martovetsky, N N; Meinke, R B; Chiesa, L; Lietzke, A F; Sabbi, G L; Seidl, P A

    2003-10-23

    An improved version of the focusing magnet for a Heavy Ion Fusion (HIF) accelerator was designed, built and tested in 2002-2003. This quadrupole has higher focusing power and lower error field than the previous version of the focusing quadrupoles successfully built and tested in 2001. We discuss the features of the new design, selected fabrication issues and test results.

  1. CESAR, 2 MeV electron storage ring; construction period; quadrupole.

    CERN Multimedia

    Service Photo; CERN PhotoLab

    1962-01-01

    One of the 24 quadrupoles. They were made of massive (non-laminated) soft iron, which at the low field-strength (35 G on the pole-tips) presented problems. Later they were fitted with shims on all 4 poles, to correct the quadrupole and sextupole components.

  2. Metric of a Slow Rotating Body with Quadrupole Moment from the Erez-Rosen Metric

    CERN Document Server

    Frutos-Alfaro, Francisco; Cordero-García, Iván; Ulloa-Esquivel, Oscar

    2012-01-01

    A metric representing a slow rotating object with quadrupole moment is obtained using the Newman-Janis formalism to include rotation into the weak limit of the Erez-Rosen metric. This metric is intended to tackle relativistic astrometry and gravitational lensing problems in which a quadrupole moment has to be taken into account.

  3. Permanency and the Foster Care System.

    Science.gov (United States)

    Lockwood, Katie K; Friedman, Susan; Christian, Cindy W

    2015-10-01

    Each year over 20,000 youth age out of the child welfare system without reaching a permanent placement in a family. Certain children, such as those spending extended time in foster care, with a diagnosed disability, or adolescents, are at the highest risk for aging out. As young adults, this population is at and increased risk of incarceration; food, housing, and income insecurity; unemployment; educational deficits; receipt of public assistance; and mental health disorders. We reviewed the literature on foster care legislation, permanency, outcomes, and interventions. The outcomes of children who age out of the child welfare system are poor. Interventions to increase permanency include training programs for youth and foster parents, age extension for foster care and insurance coverage, an adoption tax credit, and specialized services and programs that support youth preparing for their transition to adulthood. Future ideas include expanding mentoring, educational support, mental health services, and post-permanency services to foster stability in foster care placements and encourage permanency planning. Children in the child welfare system are at a high risk for physical, mental, and emotional health problems that can lead to placement instability and create barriers to achieving permanency. Failure to reach the permanency of a family leads to poor outcomes, which have negative effects on the individual and society. Supporting youth in foster care throughout transitions may mediate the negative outcomes that have historically followed placement in out-of-home care. Copyright © 2015 Mosby, Inc. All rights reserved.

  4. Dynamics of extended bodies with spin-induced quadrupole in Kerr spacetime: generic orbits

    CERN Document Server

    Han, Wen-Biao

    2016-01-01

    We discuss motions of extended bodies in Kerr spacetime by using Mathisson-Papapetrou-Dixon equations. We firstly solve the conditions for circular orbits, and calculate the orbital frequency shift due to the mass quadrupoles. The results show that we need not consider the spin-induced quadrupoles in extreme-mass-ratio inspirals for spatial gravitational wave detectors. We quantitatively investigate the temporal variation of rotational velocity of the extended body due to the coupling of quadrupole and background gravitational field. For generic orbits, we numerically integrate the Mathisson-Papapetrou-Dixon equations for evolving the motion of an extended body orbiting a Kerr black hole. By comparing with the monopole-dipole approximation, we reveal the influences of quadrupole moments of extended bodies on the orbital motion and chaotic dynamics of extreme-mass-ratio systems. We do not find any chaotic orbits for the extended bodies with physical spins and spin-induced quadrupoles. Possible implications for...

  5. Large-aperture $Nb_{3}Sn$ quadrupoles for $2^{nd}$ generation LHC IRs

    CERN Document Server

    Zlobin, A V; Chichili, D R; Huang Yu; Kashikhin, V V; Lamm, M J; Limon, P J; Mokhov, N V; Novitski, I; Peterson, T; Strait, J B; Yadav, S

    2002-01-01

    The 1/sup st/ generation of low-beta quadrupoles for the LHC interaction region (IR) was designed to achieve the nominal LHC luminosity of 10/sup 34/ cm/sup -2/s/sup -1/. Given that the lifetime of the 1/sup st/ generation IR quadrupoles is limited by ionizing radiation to 6-7 years, the 2/sup nd/ generation of IR quadrupoles has to be developed with the goal to achieve the ultimate luminosity up to 10/sup 35/ cm/sup -2/s/sup -1/. The IR quadrupole parameters such as nominal gradient, dynamic aperture and physical aperture, operation margins are the main factors limiting the machine performance. Conceptual designs of 90-mm aperture high-gradient quadrupoles, suitable for use in 2/sup nd/ generation high-luminosity LHC IRs with the similar optics, are presented. The issues related to the field gradient, field quality and operation margins are discussed. (5 refs).

  6. Combinatorial investigation of rare-earth free permanent magnets

    Science.gov (United States)

    Fackler, Sean Wu

    The combinatorial high throughput method allows one to rapidly study a large number of samples with systematically changing parameters. We apply this method to study Fe-Co-V alloys as alternatives to rare-earth permanent magnets. Rare-earth permanent magnets derive their unmatched magnetic properties from the hybridization of Fe and Co with the f-orbitals of rare-earth elements, which have strong spin-orbit coupling. It is predicted that Fe and Co may also have strong hybridization with 4d and 5d refractory transition metals with strong spin-orbit coupling. Refractory transition metals like V also have the desirable property of high temperature stability, which is important for permanent magnet applications in traction motors. In this work, we focus on the role of crystal structure, composition, and secondary phases in the origin of competitive permanent magnetic properties of a particular Fe-Co-V alloy. Fe38Co52V10, compositions are known as Vicalloys. Fe-CoV composition spreads were sputtered onto three-inch silicon wafers and patterned into discrete sample pads forming a combinatorial library. We employed highthroughput screening methods using synchrotron X-rays, wavelength dispersive spectroscopy, and magneto-optical Kerr effect (MOKE) to rapidly screen crystal structure, composition, and magnetic properties, respectively. We found that in-plane magnetic coercive fields of our Vicalloy thin films agree with known bulk values (300 G), but found a remarkable eight times increase of the out-of-plane coercive fields (˜2,500 G). To explain this, we measured the switching fields between in-plane and out-of-plane thin film directions which revealed that the Kondorsky model of 180° domain wall reversal was responsible for Vicalloy's enhanced out-of-plane coercive field and possibly its permanent magnetic properties. The Kondorsky model suggests that domain-wall pinning is the origin of Vicalloy's permanent magnetic properties, in contrast to strain, shape, or

  7. Permanent Magnetic Bearing for Spacecraft Applications

    Science.gov (United States)

    Morales, Winfredo; Fusaro, Robert; Kascak, Albert

    2008-01-01

    A permanent, totally passive magnetic bearing rig was designed, constructed, and tested. The suspension of the rotor was provided by two sets of radial permanent magnetic bearings operating in the repulsive mode. The axial support was provided by jewel bearings on both ends of the rotor. The rig was successfully operated to speeds of 5500 rpm using an air impeller. Radial and axial stiffnesses of the permanent magnetic bearings were experimentally measured and then compared to finite element results. The natural damping of the rotor was measured and a damping coefficient was calculated.

  8. Macroscopic Simulation of Isotropic Permanent Magnets

    CERN Document Server

    Bruckner, Florian; Vogler, Christoph; Heinrichs, Frank; Satz, Armin; Ausserlechner, Udo; Binder, Gernot; Koeck, Helmut; Suess, Dieter

    2015-01-01

    Accurate simulations of isotropic permanent magnets require to take the magnetization process into account and consider the anisotropic, nonlinear, and hysteretic material behaviour near the saturation configuration. An efficient method for the solution of the magnetostatic Maxwell equations including the description of isotropic permanent magnets is presented. The algorithm can easily be implemented on top of existing finite element methods and does not require a full characterization of the hysteresis of the magnetic material. Strayfield measurements of an isotropic permanent magnet and simulation results are in good agreement and highlight the importance of a proper description of the isotropic material.

  9. Macroscopic simulation of isotropic permanent magnets

    Science.gov (United States)

    Bruckner, Florian; Abert, Claas; Vogler, Christoph; Heinrichs, Frank; Satz, Armin; Ausserlechner, Udo; Binder, Gernot; Koeck, Helmut; Suess, Dieter

    2016-03-01

    Accurate simulations of isotropic permanent magnets require to take the magnetization process into account and consider the anisotropic, nonlinear, and hysteretic material behaviour near the saturation configuration. An efficient method for the solution of the magnetostatic Maxwell equations including the description of isotropic permanent magnets is presented. The algorithm can easily be implemented on top of existing finite element methods and does not require a full characterization of the hysteresis of the magnetic material. Strayfield measurements of an isotropic permanent magnet and simulation results are in good agreement and highlight the importance of a proper description of the isotropic material.

  10. Influence of Hartree-Fock exchange on the calculated Mössbauer isomer shifts and quadrupole splittings in ferrocene derivatives using density functional theory.

    Science.gov (United States)

    Nemykin, Victor N; Hadt, Ryan G

    2006-10-01

    Influence of molecular geometry, type of exchange-correlation functional, and contraction scheme of basis set applied at the iron nuclei have been tested in the calculation of 57Fe Mössbauer isomer shifts and quadrupole splittings for a wide range of ligand types, as well as oxidation and spin states, in inorganic and organometallic systems. It has been found that uncontraction of the s-part of Wachter's full-electron basis set at the iron nuclei does not appreciably improve the calculated isomer shifts. The observed correlations for all tested sets of geometries are close to each other and predominantly depend on the employed exchange-correlation functional with B3LYP functional being slightly better as compared to BPW91. Both hybrid (B3LYP) and pure (BPW91) exchange-correlation functionals are suitable for the calculation of isomer shifts in organometallic compounds. Surprisingly, it has been found that the hybrid B3LYP exchange-correlation functional completely fails in accurate prediction of quadrupole splittings in ferrocenes, while performance of the pure BPW91 functional for the same systems was excellent. This observation has been explained on the basis of relationship between the amount of Hartree-Fock exchange involved in the applied exchange-correlation functional and the calculated HOMO-LUMO energy gap in ferrocenes. On the basis of this explanation, use of only pure exchange-correlation functionals has been suggested for accurate prediction of Mössbauer spectra parameters in ferrocenes.

  11. Optimal filtering in multipulse sequences for nuclear quadrupole resonance detection

    Science.gov (United States)

    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. Microscopic analysis of quadrupole-octupole shape evolution

    Directory of Open Access Journals (Sweden)

    Nomura Kosuke

    2015-01-01

    Full Text Available 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.

  13. Confining rigid balls by mimicking quadrupole ion trapping

    CERN Document Server

    Fan, Wenkai; Wang, Sihui; Zhou, Huijun

    2016-01-01

    The rotating saddle not only is an interesting system that is able to trap a ball near its saddle point, but can also intuitively illustrate the operating principles of quadrupole ion traps in modern physics. Unlike the conventional models based on the mass-point approximation, we study the stability of a ball in a rotating-saddle trap using rigid-body dynamics. The stabilization condition of the system is theoretically derived and subsequently verified by experiments. The results are compared with the previous mass-point model, giving large discrepancy as the curvature of the ball is comparable to that of the saddle. We also point out that the spin angular velocity of the ball is analogous to the cyclotron frequency of ions in an external magnetic field utilized in many prevailing ion-trapping schemes.

  14. Radio Frequency Interference Suppression for Landmine Detection by Quadrupole Resonance

    Directory of Open Access Journals (Sweden)

    Liu Guoqing

    2006-01-01

    Full Text Available The quadrupole resonance (QR technology can be used as a confirming sensor for buried plastic landmine detection by detecting the explosives within the mine. We focus herein on the detection of TNT mines via the QR sensor. Since the frequency of the QR signal is located within the AM radio frequency band, the QR signal can be corrupted by strong radio frequency interferences (RFIs. Hence to detect the very weak QR signal, RFI mitigation is essential. Reference antennas, which receive RFIs only, can be used together with the main antenna, which receives both the QR signal and the RFIs, for RFI mitigation. The RFIs are usually colored both spatially and temporally, and hence exploiting only the spatial diversity of the antenna array may not give the best performance. We exploit herein both the spatial and temporal correlations of the RFIs to improve the TNT detection performance.

  15. $Nb_{3}Sn$ quadrupole magnets for the LHC IR

    CERN Document Server

    Sabbi, G L; Chiesa, L; Coccoli, M; Dietderich, D R; Ferracin, P; Gourlay, S A; Hafalia, R R; Lietzke, A F; McInturff, A D; Scanlan, R M

    2003-01-01

    The development of insertion quadrupoles with 205 T/m gradient and 90 mm bore represents a promising strategy to achieve the ultimate luminosity goal of 2.5 * 10/sup 34/ cm/sup -2/s/sup -1/ at the Large Hadron Collider (LHC). At present, Nb/sub 3/Sn is the only practical conductor which can meet these requirements. Since Nb/sub 3/Sn is brittle, and considerably more strain sensitive than NbTi, the design concepts and fabrication techniques developed for NbTi magnets need to be modified appropriately. In addition, IR magnets must provide high field quality and operate reliably under severe radiation loads. The results of conceptual design studies addressing these issues are presented. (25 refs).

  16. Alternative Mechanical Structure for LARP Nb3Sn Quadrupoles

    Energy Technology Data Exchange (ETDEWEB)

    Anerella, M.; Cozzolino, J.; Ambrosio, G.; Caspi, S.; Felice, H.; Kovach, P.; Lamm, M.; Sabbi, G.; Schmalzle, J.; Wanderer, P.

    2010-08-01

    An alternative structure for the 120 mm Nb{sub 3}Sn quadrupole magnet presently under development for use in the upgrade for LHC at CERN is presented. The goals of this structure are to build on the existing technology developed in LARP with the LQ and HQ series magnets and to further optimize the features required for operation in the accelerator. These features include mechanical alignment needed for field quality and provisions for cold mass cooling with 1.9 K helium in a helium pressure vessel. The structure will also optimize coil azimuthal and axial pre-load for high gradient operation, and will incorporate features intended to improve manufacturability, thereby improving reliability and reducing cost.

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

    Science.gov (United States)

    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.

  18. Nuclear magnetic and quadrupole resonance studies of the stripes materials

    Energy Technology Data Exchange (ETDEWEB)

    Grafe, H.-J., E-mail: h.grafe@ifw-dresden.de [IFW Dresden, Institute for Solid State Research, P.O. Box 270116, D-01171 Dresden (Germany)

    2012-11-01

    Nuclear Magnetic and Quadrupole Resonance (NMR/NQR) is a powerful tool to probe electronic inhomogeneities in correlated electron systems. Its local character allows for probing different environments due to spin density modulations or inhomogeneous doping distributions emerging from the correlations in these systems. In fact, NMR/NQR is not only sensitive to magnetic properties through interaction of the nuclear spin, but also allows to probe the symmetry of the charge distribution and its homogeneity, as well as structural modulations, through sensitivity to the electric field gradient (EFG). We review the results of NMR and NQR in the cuprates from intrinsic spatial variations of the hole concentration in the normal state to stripe order at low temperatures, thereby keeping in mind the influence of doping induced disorder and inhomogeneities. Finally, we briefly discuss NQR evidence for local electronic inhomogeneities in the recently discovered iron pnictides, suggesting that electronic inhomogeneities are a common feature of correlated electron systems.

  19. LHC interaction region quadrupole cryostat design and fabrication

    CERN Document Server

    Nicol, T H; Huang, Y; Page, Thomas M

    2002-01-01

    The cryostat of a Large Hadron Collider (LHC) Interaction Region (IR) quadrupole magnet consists of all components of the inner triplet except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, to house all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations, and must be able to be manufactured at low cost. The major components of the cryostat are the vacuum vessel, thermal shield, multilayer insulation system, cryogenic piping, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course of their...

  20. Quadrupole collectivity of neutron-rich Neon isotopes

    CERN Document Server

    Rodríguez-Guzman, R R; Robledo, L M

    2003-01-01

    The angular momentum projected Generator Coordinate Method, with the quadrupole moment as collective coordinate and the Gogny force (D1S) as the effective interaction, is used to describe the properties of the ground state and low-lying excited states of the even-even Neon isotopes $^{20-34}$Ne, that is, from the stability valley up to the drip-line. It is found that the ground state of the N=20 nucleus $^{30}$Ne is deformed but to a lesser extent than the N=20 isotope of the Magnesium. In the calculations, the isotope $^{32}$Ne is at the drip-line in good agreement with other theoretical predictions. On the other hand, rather good agreement with experimental data for many observables is obtained.

  1. Low Frequency Nuclear Quadrupole Resonance with SQUID Amplifiers

    Science.gov (United States)

    Clarke, John

    1994-02-01

    The dc SQUID (Superconducting QUantum Interference Device) can be configured as an ampli­fier of spin-echos with a noise temperature of approximately 10 mK (f/1 M Hz) at an operating temperature of 1.5 K. A Fourier transform spectrometer based on a SQUID with a superconducting input circuit and operated in a flux-locked loop is used to obtain nuclear quadrupole resonance (NQR) spectra in a broadband m ode over the bandwith 0 -1 M Hz. Spin-echo spectra of 14N in NH4ClO4 reveal sharp NQR resonances, obtained simultaneously, at 17.4, 38.8 and 56.2 kHz. At 1.5 K, the measured longitudinal and transverse relaxation times T1 and T2 for the 38.8 kHz transition are 63 ± 3 ms and 22±2 ms, respectively.

  2. Beam-induced quench test of LHC main quadrupole

    CERN Document Server

    Priebe, A; Dehning, B; Effinger, E; Emery, J; Holzer, E B; Kurfuerst, C; Nebot Del Busto, E; Nordt, A; Sapinski, M; Steckert, J; Verweij, A; Zamantzas, C

    2011-01-01

    Unexpected beam loss might lead to a transition of the accelerator superconducting magnet to a normal conducting state. The LHC beam loss monitoring (BLM) system is designed to abort the beam before the energy deposited in the magnet coils reach a quench-provoking level. In order to verify the threshold settings generated by simulation, a series of beam-induced quench tests at various beam energies has been performed. The beam losses are generated by means of an orbital bump peaked in one of main quadrupole magnets (MQ). The analysis includes not only BLM data but also the quench protection system (QPS) and cryogenics data. The measurements are compared to Geant4 simulations of energy deposition inside the coils and corresponding BLM signal outside the cryostat.

  3. Permanent Magnet Boosted Modular Switched Reluctance Motor

    Directory of Open Access Journals (Sweden)

    SZABÓ Loránd

    2016-10-01

    Full Text Available This paper deals with the analyses of a novel motor structure obtained by boosting with permanent magnets a formerly studied modular switched reluctance motor. Upon dynamic simulation results the improvements of the proposed motor are emphasized.

  4. Practical considerations for permanent total enclosures

    Energy Technology Data Exchange (ETDEWEB)

    Worrall, M. [Amcec Adsorption Systems, Schaumburg, IL (United States)

    1997-12-31

    This paper considers some of the practical consideration of Permanent Total Enclosures (PTEs) for gravure printing facilities. In particular the dispersion of fugitive losses from the presses by thermal air currents generated by heat from the press dryers.

  5. 78 FR 14122 - Revocation of Permanent Variances

    Science.gov (United States)

    2013-03-04

    ... Occupational Safety and Health Administration Revocation of Permanent Variances AGENCY: Occupational Safety and Health Administration (OSHA), Labor. ACTION: Notice of revocation. SUMMARY: With this notice, OSHA is... into consideration these newly corrected cross references. DATES: The effective date of the...

  6. Permanent traffic counters maintained by the NMDOT

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — A point dataset representing the permanent traffic counters maintained by the NMDOT. Event mapped dataset by LRS info provided by Traffic group.

  7. Novel Switched Flux Permanent Magnet Machine Topologies

    Institute of Scientific and Technical Information of China (English)

    诸自强

    2012-01-01

    This paper overviews various switched flux permanent magnet machines and their design and performance features,with particular emphasis on machine topologies with reduced magnet usage or without using magnet,as well as with variable flux capability.

  8. Computing matrix permanent with collective boson operators

    CERN Document Server

    Huh, Joonsuk

    2016-01-01

    Computing permanents of matrices are known to be a classically hard problem that the computational cost grows exponentially with the size of the matrix increases. So far, there exist a few classical algorithms to compute the matrix permanents in deterministic and in randomized ways. By exploiting the series expansion of products of boson operators regarding collective boson operators, a generalized algorithm for computing permanents is developed that the algorithm can handle the arbitrary matrices with repeated columns and rows. In a particular case, the formula is reduced to Glynn's form. Not only the algorithm can be used for a deterministic direct calculation of the matrix permanent but also can be expressed as a sampling problem like Gurvits's randomized algorithm.

  9. [Permanent education in health: a review].

    Science.gov (United States)

    Miccas, Fernanda Luppino; Batista, Sylvia Helena Souza da Silva

    2014-02-01

    To undertake a meta-synthesis of the literature on the main concepts and practices related to permanent education in health. A bibliographical search was conducted for original articles in the PubMed, Web of Science, LILACS, IBECS and SciELO databases, using the following search terms: "public health professional education", "permanent education", "continuing education", "permanent education health". Of the 590 articles identified, after applying inclusion and exclusion criteria, 48 were selected for further analysis, grouped according to the criteria of key elements, and then underwent meta-synthesis. The 48 original publications were classified according to four thematic units of key elements: 1) concepts, 2) strategies and difficulties, 3) public policies and 4) educational institutions. Three main conceptions of permanent education in health were found: problem-focused and team work, directly related to continuing education and education that takes place throughout life. The main strategies for executing permanent education in health are discussion, maintaining an open space for permanent education , and permanent education clusters. The most limiting factor is mainly related to directly or indirect management. Another highlight is the requirement for implementation and maintenance of public policies, and the availability of financial and human resources. The educational institutions need to combine education and service aiming to form critical-reflexive graduates. The coordination between health and education is based as much on the actions of health services as on management and educational institutions. Thus, it becomes a challenge to implement the teaching-learning processes that are supported by critical-reflexive actions. It is necessary to carry out proposals for permanent education in health involving the participation of health professionals, teachers and educational institutions. To undertake a meta-synthesis of the literature on the main concepts and

  10. Determining gaseous composition of fluid inclusions with quadrupole mass spectrometer

    Institute of Scientific and Technical Information of China (English)

    ZHU; Heping

    2002-01-01

    [1]Joseph, R. G., Stephen, E. K., Factors affecting gas analysis of inclusion fluid by quadrupole mass spectrometry, Geo-chimica et Acta, 1995, 59(19): 3977-3986.[2]Masakatsu, S., Takayuki, S., Naoto, T., Analysis of fluid inclusion gases from geothermal systems, using a rapid-scanning quadrupole mass spectrometer, Eur. J. Mineral., 1992, 4: 895-906.[3]Van den Kerkhof, A. M., Isochoric phase diagrams in the systems CO2-CH4 and CO2-N2: Application to fluid inclusions, Geochimica et Cosmochimica Acta, 1990, 54: 621-629.[4]Colin, B., Michael, P. S., Mass spectrometric determination of gases in individual fluid inclusions in natural minerals, Anal. Chem., 1986, 58: 1330-1333.[5]David, I. N., Fredrick, J. S., Analysis of volatiles in fluid inclusions by mass spectrometry, Chemical Geology, 1987, 61: 1-10.[6]Yoichi, M., Ryo, K., Takayuki, S. et al., Gas composition of fluid inclusion from the Mori Geothermal Reservoir, South-western Hokkaido, Japan, Resource Geology, 1997, 47(5): 283-291.[7]Lu Huanzhang, Guo Dijiang, Progress and trends of researches on fluid inclusions, Geological Review, 2000, 46(4): 385-392.[8]Xia Xinyu, Wang Xianbin, Chen Jiangfeng, Geningjie, composition of fluid inclusions and CO2 carbon isotope of ultra-high pressure metamorphic rocks in Shuanghe area, Dabieshan Mountain, Science in China (in Chinese), Ser. D, 1999, 29(4): 314-320.

  11. A surface-electrode quadrupole guide for electrons

    Energy Technology Data Exchange (ETDEWEB)

    Hoffrogge, Johannes Philipp

    2012-12-19

    This thesis reports on the design and first experimental realization of a surface-electrode quadrupole guide for free electrons. The guide is based on a miniaturized, planar electrode layout and is driven at microwave frequencies. It confines electrons in the near-field of the microwave excitation, where strong electric field gradients can be generated without resorting to resonating structures or exceptionally high drive powers. The use of chip-based electrode geometries allows the realization of versatile, microstructured potentials with the perspective of novel quantum experiments with guided electrons. I present the design, construction and operation of an experiment that demonstrates electron confinement in a planar quadrupole guide for the first time. To this end, electrons with kinetic energies from one to ten electron-volts are guided along a curved electrode geometry. The stability of electron guiding as a function of drive parameters and electron energy has been studied. A comparison with numerical particle tracking simulations yields good qualitative agreement and provides a deeper understanding of the electron dynamics in the guiding potential. Furthermore, this thesis gives a detailed description of the design of the surface-electrode layout. This includes the development of an optimized coupling structure to inject electrons into the guide with minimum transverse excitation. I also discuss the extension of the current setup to longitudinal guide dimensions that are comparable to or larger than the wavelength of the drive signal. This is possible with a modified electrode layout featuring elevated signal conductors. Electron guiding in the field of a planar, microfabricated electrode layout allows the generation of versatile and finely structured guiding potentials. One example would be the realization of junctions that split and recombine a guided electron beam. Furthermore, it should be possible to prepare electrons in low-lying quantum mechanical

  12. Micromachined permanent magnets and their MEMS applications

    Science.gov (United States)

    Cho, Hyoung Jin

    2002-01-01

    In this research, new micromachined permanent magnets have been proposed, developed and characterized for MEMS applications. In realizing micromachined permanent magnets, a new electroplating technique using external magnetic field and a bumper filling technique using a photolithographically defined mold with resin bonded magnetic particles have been developed. The newly developed micromachining techniques allow thick film-type permanent magnet components to be integrated to magnetic MEMS devices with dimensional control and alignment. Permanent magnet arrays with the dimensions ranging from 30 mum to 200 mum have been developed with an energy density up to 2.7 kJ/m3 in precisely defined forms in the micro scale. For the applications of the permanent magnets developed in this work, three novel magnetic MEMS devices such as a bi-directional magnetic actuator, a magnetically driven optical scanner, and a magnetic cell separator have been successfully realized. After design and modeling, each device has been fabricated and fully characterized. The bi-directional actuator with the electroplated permanent magnet array has achieved bi-directional motion clearly and shown good agreement with the analytical and simulated models. The optical scanner has shown linear bi-directional response under static actuation and stable bi-directional scanning performance under dynamic actuation. As a potential BioMEMS application of the developed permanent magnet, the prototype magnetic cell separator using the electroplated permanent magnet strip array has been proposed and demonstrated for magnetic bead patterning. In conclusion, new thick film-type, electroplated CoNiMnP and epoxy resin bonded Sr-ferrite permanent magnets have been developed and characterized, and then, three new magnetic MEMS devices using the permanent magnets such as a bi-directional magnetic actuator, an optical scanner and a magnetic cell separator have been realized in this research. The new micromachined

  13. Sporadic hemiplegic migraine with permanent neurological deficits.

    Science.gov (United States)

    Schwedt, Todd J; Zhou, Jiying; Dodick, David W

    2014-01-01

    By definition, the neurologic impairments of hemiplegic migraine are reversible. However, a few cases of permanent neurologic deficits associated with hemiplegic migraine have been reported. Herein, we present the case of a patient with permanent impairments because of hemiplegic migraine despite normalization of associated brain magnetic resonance imaging abnormalities. Cases like these suggest the need to consider aggressive prophylactic therapy for patients with recurrent hemiplegic migraine attacks.

  14. Macroscopic Simulation of Isotropic Permanent Magnets

    OpenAIRE

    Bruckner, Florian; Abert, Claas; Vogler, Christoph; Heinrichs, Frank; Satz, Armin; Ausserlechner, Udo; Binder, Gernot; Koeck, Helmut; Suess, Dieter

    2015-01-01

    Accurate simulations of isotropic permanent magnets require to take the magnetization process into account and consider the anisotropic, nonlinear, and hysteretic material behaviour near the saturation configuration. An efficient method for the solution of the magnetostatic Maxwell equations including the description of isotropic permanent magnets is presented. The algorithm can easily be implemented on top of existing finite element methods and does not require a full characterization of the...

  15. Quantum Permanents and Hafnians via Pfaffians

    Science.gov (United States)

    Jing, Naihuan; Zhang, Jian

    2016-10-01

    Quantum determinants and Pfaffians or permanents and Hafnians are introduced on the two-parameter quantum general linear group. Fundamental identities among quantum Pf, Hf, and det are proved in the general setting. We show that there are two special quantum algebras among the quantum groups, where the quantum Pfaffians have integral Laurent polynomials as coefficients. As a consequence, the quantum Hafnian is computed by a closely related quantum permanent and identical to the quantum Pfaffian on this special quantum algebra.

  16. Permanent magnet system of alpha magnetic spectrometer

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Alpha magnetic spectrometer (AMS) is the first large magnetic spectrometer in space. Its precursor flight was completed successfully in June 1998. The key part of AMS is the permanent magnet system, which was built by the Institute of Electric Engineering, the Institute of High Energy Physics and the Chinese Academy of Launch Vehicle Technology. This system includes a permanent magnet made of high grade NdFeB and a support structure. The unique design of the permanent magnet based on the magic ring fulfills the severe requirements on the magnetic field leakage and the dipole moment for space experiments. The permanent magnet weighs about 2 tons, and provides a geometric acceptance of 0.6 m2 ·sr and an analyzing power BL2 of 0.135 T·m2. It works up to 40℃ without demagnetization. The main structure is a thin double shell, which undergoes the strong magnetic force and torque of the permanent magnet, as well as the large load during launching and landing. The permanent magnet system fulfills the requirements from AMS, and satisfies the strict safety standards of NASA.

  17. Permanent magnet system of alpha magnetic spectrometer

    Institute of Scientific and Technical Information of China (English)

    陈和生

    2000-01-01

    Alpha magnetic spectrometer (AMS) is the first large magnetic spectrometer in space. Its precursor flight was completed successfully in June 1998. The key part of AMS is the permanent magnet system, which was built by the Institute of Electric Engineering, the Institute of High Energy Physics and the Chinese Academy of Launch Vehicle Technology. This system includes a permanent magnet made of high grade NdFeB and a support structure. The unique design of the permanent magnet based on the magic ring fulfills the severe requirements on the magnetic field leakage and the dipole moment for space experiments. The permanent magnet weighs about 2 tons, and provides a geometric acceptance of 0.6 m2·sr and an analyzing power BL2 of 0.135 T·m2. It works up to 40℃ without demagnetization. The main structure is a thin double shell, which undergoes the strong magnetic force and torque of the permanent magnet, as well as the large load during launching and landing. The permanent magnet system fulfills the requirem

  18. Workplace bullying a risk for permanent employees.

    Science.gov (United States)

    Keuskamp, Dominic; Ziersch, Anna M; Baum, Fran E; Lamontagne, Anthony D

    2012-04-01

    We tested the hypothesis that the risk of experiencing workplace bullying was greater for those employed on casual contracts compared to permanent or ongoing employees. A cross-sectional population-based telephone survey was conducted in South Australia in 2009. Employment arrangements were classified by self-report into four categories: permanent, casual, fixed-term and self-employed. Self-report of workplace bullying was modelled using multiple logistic regression in relation to employment arrangement, controlling for sex, age, working hours, years in job, occupational skill level, marital status and a proxy for socioeconomic status. Workplace bullying was reported by 174 respondents (15.2%). Risk of workplace bullying was higher for being in a professional occupation, having a university education and being separated, divorced or widowed, but did not vary significantly by sex, age or job tenure. In adjusted multivariate logistic regression models, casual workers were significantly less likely than workers on permanent or fixed-term contracts to report bullying. Those separated, divorced or widowed had higher odds of reporting bullying than married, de facto or never-married workers. Contrary to expectation, workplace bullying was more often reported by permanent than casual employees. It may represent an exposure pathway not previously linked with the more idealised permanent employment arrangement. A finer understanding of psycho-social hazards across all employment arrangements is needed, with equal attention to the hazards associated with permanent as well as casual employment. © 2012 The Authors. ANZJPH © 2012 Public Health Association of Australia.

  19. EDITORIAL: Permanent revolution - or evolution?

    Science.gov (United States)

    Dobson, Ken

    1998-03-01

    Honorary Editor It was that temporary Bolshevik Leon Trotsky who developed the principle of `permanent revolution', a principle that perhaps characterizes the recent history of education in (south) Britain more than does, say, principles traditionally associated with the Conservative or Labour parties. As this editorial is being written, changes are being made to primary school education, and the long-awaited details of the post-Dearing reorganizing of post-16 education are yet to hit the overful bookshelves and filing cabinets of school heads and examination board officials. But something unique has happened recently which might have surprised even Trotsky. The Secretary of State for Education has set up targets for primary school pupils' attainment and threatened (or promised) to resign if they are not met within the lifetime of our newly elected parliament. Of course, if Mr Blunkett is still in a position to resign at that stage he will have been the longest serving Secretary of State since time immemorial. But we should not carp: this is truly a revolutionary idea. Not the promise to resign - although this idea is not so fashionable now as it once was. The revolutionary idea is that a major change to an educational process is actually being made that carries with it a predicted and testable outcome. By contrast, when school physics was refreshed a generation ago by the introduction of Nuffield courses at both pre- and post-16 stages, no `targets' were set. I and many other physics teachers certainly preferred teaching these to teaching their predecessor syllabuses, and might even dare to assert that the pupils liked them too. But we still don't really know whether or not they learned more - or even better - physics. Very little happened as far as the outside world was concerned: the usual fraction of students gave up physics at the usual ages, and those who were examined didn't really get a better reward for their more up-to-date and more enjoyably learned

  20. Effect of maximum torque according to the permanent magnet configuration of a brushless dc motor with concentrated winding

    Science.gov (United States)

    Lee, Kab-Jae; Kim, Sol; Lee, Ju; Oh, Jae-Eung

    2003-05-01

    A brushless dc (BLDC) motor, which has a permanent magnet (PM) component, is a potential candidate for hybrid or electric vehicle applications. Minimizing the BLDC motor size is an important requirement for application. This requirement is usually satisfied by adopting a high performance permanent magnet or improved winding methods. The PM configuration is also a critical point in design. This article presents the effect of the PM configuration on motor performance, especially the maximum torque. Four representative BLDC motor types are analytically investigated under the condition that the volume of the PM and magnetic material is constant. An embedded interior permanent magnet motor has the best torque performance the maximum torque of which is more than 1.5 times larger than that of the surface mounted permanent magnet motor. The performance of back electromotive force, instantaneous torques is also investigated.

  1. A study of generator performance with linear permanent magnet in various coil configuration and rotor-stator geometry

    Science.gov (United States)

    Asy'ari, Hasyim; Sarjito, Prasetio, Septian Heri

    2017-04-01

    The aim of the research work describe in this paper was to design and optimize a permanent magnet linear generator for renewable energy power plants. It is cover of first stage of designing stator and rotor permanent magnet linear generator. Stator design involves determining dimensions, number of slots, diameter of wire, and the number of winding in each slot. The design of the rotor includes rotor manufacture of PVC pipe material, 10 pieces of permanent magnet type ferrite 271 mikroweber, and resin. The second stage was to assemble the stator and rotor that has been done in the first stage to be a permanent magnet linear generator. The third stage was to install a permanent magnet linear generator with induction motors. Further stage was to test performance of a permanent magnet linear generator by utilizing of induction motor as a prime mover experimentally. In this study, permanent magnet linear generator with a rotor consists of five pairs of permanent magnets. The stator consists of 6 slots of the stator frame, each slot mounted stator coil of 200, 300, 400, 500, and 800 windings, and dimensions of wire used was 0.4 mm. The stator frame was made from acrylic. Results of the experiment that, permanent magnet linear generator when no load was able to generate a DC voltage of 14.5 volts at 300 rpm, and at the output of the linear generator when it is connected to the DC fan as a load only generated of 6.7 volts. It concludes that permanent magnet linear generator output can be used as an input device hybrid system. Data obtained from this experiment in laboratory scale can be developed in a larger scale by varying the type of magnet being used, the number of windings, and the speed used to generate more power.

  2. Mechanism of hybrid-magnetic-circuit multi-couple motor

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Discusses the interval between laminations in a permanent-magnet inductor motor which makes the air-gap magnetic field produced by the permanent magnet very uneven in the axial direction, and limits the performance of a motor. Proposes a hybrid-magnetic-circuit multi-couple motor to compensate for the uneven air-gap magnetic field, thereby improving the performance of a motor.

  3. Reconstruction of the number and positions of dipoles and quadrupoles using an algebraic method

    Energy Technology Data Exchange (ETDEWEB)

    Nara, Takaaki [University of Electro-Communications, 1-5-1, Chofugaoka, Chofu-city, Tokyo, 182-8585 (Japan)], E-mail: nara@mce.uec.ac.jp

    2008-11-01

    Localization of dipoles and quadrupoles is important in inverse potential analysis, since they can effectively express spatially extended sources with a small number of parmeters. This paper proposes an algebraic method for reconstruction of pole positions as well as the number of dipole-quadrupoles without providing an initial parameter guess or iterative computing forward solutions. It is also shown that a magnetoencephalography inverse problem with a source model of dipole-quadrupoles in 3D space is reduced into the same problem as in 2D space.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosio, G. [Fermilab; Chlachidze, G. [Fermilab; Wanderer, P. [Brookhaven; Ferracin, P. [CERN; Sabbi, G. [LBNL, Berkeley

    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.

  5. Wireless power transfer based on magnetic quadrupole coupling in dielectric resonators

    Science.gov (United States)

    Song, Mingzhao; Iorsh, Ivan; Kapitanova, Polina; Nenasheva, Elizaveta; Belov, Pavel

    2016-01-01

    We numerically investigate a magnetic resonant wireless power transfer system based on high refractive index dielectric resonators. We propose to operate at magnetic quadrupole mode of the resonators to enlarge the efficiency due to minimization of ohmic and radiation losses. Numerical estimation predicts the 80% efficiency of the wireless power transfer (WPT) system operating at quadrupole mode at 300 MHz. Moreover, the system operating at magnetic quadrupole mode is capable of transferring power with 70% efficiency when the receiver rotates 90°. We verify the simulated results by experimental investigation of the WPT system based on microwave ceramic resonators (ɛ = 80 and tanδ = 10-4).

  6. Temperature and angular momentum dependence of the quadrupole deformation in sd-shell

    Indian Academy of Sciences (India)

    P A Ganai; J A Sheikh; I Maqbool; R P Singh

    2009-11-01

    Temperature and angular momentum dependence of the quadrupole deformation is studied in the middle of the sd-shell for 28Si and 27Si isotopes using the spherical shell model approach. The shell model calculations have been performed using the standard universal sd-shell (USD) interaction and the canonical partition function constructed from the calculated eigensolutions. It is shown that the extracted average quadrupole moments show a transitional behaviour as a function of temperature and the infered transitional temperature is shown to vary with angular momentum. The quadrupole deformation of the individual eigenstate is also analysed.

  7. High performance hybrid magnetic structure for biotechnology applications

    Science.gov (United States)

    Humphries, David E [El Cerrito, CA; Pollard, Martin J [El Cerrito, CA; Elkin, Christopher J [San Ramon, CA

    2009-02-03

    The present disclosure provides a high performance hybrid magnetic structure made from a combination of permanent magnets and ferromagnetic pole materials which are assembled in a predetermined array. The hybrid magnetic structure provides means for separation and other biotechnology applications involving holding, manipulation, or separation of magnetic or magnetizable molecular structures and targets. Also disclosed are further improvements to aspects of the hybrid magnetic structure, including additional elements and for adapting the use of the hybrid magnetic structure for use in biotechnology and high throughput processes.

  8. Hybrid Metaheuristics

    CERN Document Server

    2013-01-01

    The main goal of this book is to provide a state of the art of hybrid metaheuristics. The book provides a complete background that enables readers to design and implement hybrid metaheuristics to solve complex optimization problems (continuous/discrete, mono-objective/multi-objective, optimization under uncertainty) in a diverse range of application domains. Readers learn to solve large scale problems quickly and efficiently combining metaheuristics with complementary metaheuristics, mathematical programming, constraint programming and machine learning. Numerous real-world examples of problems and solutions demonstrate how hybrid metaheuristics are applied in such fields as networks, logistics and transportation, bio-medical, engineering design, scheduling.

  9. Electric quadrupole interaction in cubic BCC α-Fe

    Energy Technology Data Exchange (ETDEWEB)

    Błachowski, A.; Komędera, K. [Mössbauer Spectroscopy Division, Institute of Physics, Pedagogical University, ul. Podchorążych 2, PL-30-084 Kraków (Poland); Ruebenbauer, K., E-mail: sfrueben@cyf-kr.edu.pl [Mössbauer Spectroscopy Division, Institute of Physics, Pedagogical University, ul. Podchorążych 2, PL-30-084 Kraków (Poland); Cios, G.; Żukrowski, J. [AGH University of Science and Technology, Academic Center for Materials and Nanotechnology, Av. A. Mickiewicza 30, PL-30-059 Kraków (Poland); Górnicki, R. [RENON, ul. Gliniana 15/15, PL-30-732 Kraków (Poland)

    2016-07-15

    Mössbauer transmission spectra for the 14.41-keV resonant line in {sup 57}Fe have been collected at room temperature by using {sup 57}Co(Rh) commercial source and α-Fe strain-free single crystal as an absorber. The absorber was magnetized to saturation in the absorber plane perpendicular to the γ-ray beam axis applying small external magnetic field. Spectra were collected for various orientations of the magnetizing field, the latter lying close to the [110] crystal plane. A positive electric quadrupole coupling constant was found practically independent on the field orientation. One obtains the following value V{sub zz} = +1.61(4) × 10{sup 19} Vm{sup −2} for the (average) principal component of the electric field gradient (EFG) tensor under assumption that the EFG tensor is axially symmetric and the principal axis is aligned with the magnetic hyperfine field acting on the {sup 57}Fe nucleus. The nuclear spectroscopic electric quadrupole moment for the first excited state of the {sup 57}Fe nucleus was adopted as +0.17 b. Similar measurement was performed at room temperature using as-rolled polycrystalline α-Fe foil of high purity in the zero external field. Corresponding value for the principal component of the EFG was found as V{sub zz} = +1.92(4) × 10{sup 19} Vm{sup −2}. Hence, it seems that the origin of the EFG is primarily due to the local (atomic) electronic wave function distortion caused by the spin–orbit interaction between effective electronic spin S and incompletely quenched electronic angular momentum L. It seems as well that the lowest order term proportional to the product L·λ·S dominates, as no direction dependence of the EFG principal component is seen. The lowest order term is isotropic for a cubic symmetry as one has λ=λ 1 for cubic systems with the symbol 1 denoting unit operator and λ being the coupling parameter. - Highlights: • Precision of MS the same as MAPON • Real scans versus magnetization direction • A challenge

  10. Fast Fourier Transform Chlorine Nuclear Quadrupole Resonance Spectroscopy.

    Science.gov (United States)

    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

  11. Permanent Magnet Eddy Current Loss Analysis of a Novel Motor Integrated Permanent Magnet Gear

    DEFF Research Database (Denmark)

    Zhang, Yuqiu; Lu, Kaiyuan; Ye, Yunyue

    2012-01-01

    In this paper, a new motor integrated permanent magnet gear (MIPMG) is discussed. The focus is on eddy current loss analysis associated to permanent magnets (PMs). A convenient model of MIPMG is provided based on 2-D field-motion coupled time-stepping finite element method for transient eddy...

  12. Triple Quadrupole Versus High Resolution Quadrupole-Time-of-Flight Mass Spectrometry for Quantitative LC-MS/MS Analysis of 25-Hydroxyvitamin D in Human Serum

    Science.gov (United States)

    Geib, Timon; Sleno, Lekha; Hall, Rabea A.; Stokes, Caroline S.; Volmer, Dietrich A.

    2016-08-01

    We describe a systematic comparison of high and low resolution LC-MS/MS assays for quantification of 25-hydroxyvitamin D3 in human serum. Identical sample preparation, chromatography separations, electrospray ionization sources, precursor ion selection, and ion activation were used; the two assays differed only in the implemented final mass analyzer stage; viz. high resolution quadrupole-quadrupole-time-of-flight (QqTOF) versus low resolution triple quadrupole instruments. The results were assessed against measured concentration levels from a routine clinical chemiluminescence immunoassay. Isobaric interferences prevented the simple use of TOF-MS spectra for extraction of accurate masses and necessitated the application of collision-induced dissociation on the QqTOF platform. The two mass spectrometry assays provided very similar analytical figures of merit, reflecting the lack of relevant isobaric interferences in the MS/MS domain, and were successfully applied to determine the levels of 25-hydroxyvitamin D for patients with chronic liver disease.

  13. 31 CFR 515.335 - Permanent resident alien.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States. ...

  14. Permanence and global attractivity for Lotka-Volterra difference systems.

    Science.gov (United States)

    Lu, Z; Wang, W

    1999-09-01

    The permanence and global attractivity for two-species difference systems of Lotka-Volterra type are considered. It is proved that a cooperative system cannot be permanent. For a permanent competitive system, the explicit expression of the permanent set E is obtained and sufficient conditions are given to guarantee the global attractivity of the positive equilibrium of the system.

  15. The effect of the cosmological constant on gravitational wave quadrupole signal

    CERN Document Server

    Somlai, L A

    2016-01-01

    In this study the effects of a non-zero cosmological constant $\\Lambda$ on a quadrupole signal are studied. The linearized approximation of general relativity was used, so the metric can be written as $g_{\\mu\

  16. Novel tandem quadrupole-acceleration-deceleration mass spectrometer for neutralization-reionization studies.

    Science.gov (United States)

    Turecek, F; Gu, M; Shaffer, S A

    1992-07-01

    A new tandem mass spectrometer of the quadrupole-acceleration lens-deceleration. lens-quadrupole (QADQ) configuration is described. The instrument is designed for neutralization-reionization studies and consists of a 2000-u quadrupole mass analyzer as MS-I, an acceleration electrostatic lens, a series of three differentially pumped collision cells, and an electrostatic deceleration lens, energy filter, and another 2000-u quadrupole mass analyzer as MS-II. The ion optical system achieves high total ion transmission for 5-9-keV ions. Unit mass resolution in neutralization-reionization mass spectra of aromatic compounds is demonstrated. Mass, kinetic energy, and linked scans at various levels of mass resolution and sensitivity are described.

  17. Microscopic derivation of the Bohr-Mottelson collective Hamiltonian and its application to quadrupole shape dynamics

    Science.gov (United States)

    Matsuyanagi, Kenichi; Matsuo, Masayuki; Nakatsukasa, Takashi; Yoshida, Kenichi; Hinohara, Nobuo; Sato, Koichi

    2016-06-01

    We discuss the nature of the low-frequency quadrupole vibrations from small-amplitude to large-amplitude regimes. We consider full five-dimensional quadrupole dynamics including three-dimensional rotations restoring the broken symmetries as well as axially symmetric and asymmetric shape fluctuations. Assuming that the time evolution of the self-consistent mean field is determined by five pairs of collective coordinates and collective momenta, we microscopically derive the collective Hamiltonian of Bohr and Mottelson, which describes low-frequency quadrupole dynamics. We show that the five-dimensional collective Schrödinger equation is capable of describing large-amplitude quadrupole shape dynamics seen as shape coexistence/mixing phenomena. We summarize the modern concepts of microscopic theory of large-amplitude collective motion, which is underlying the microscopic derivation of the Bohr-Mottelson collective Hamiltonian.

  18. Optimized Fast and Sensitive Acquisition Methods for Shotgun Proteomics on a Quadrupole Orbitrap Mass Spectrometer

    DEFF Research Database (Denmark)

    Kelstrup, Christian D; Young, Clifford; Lavallee, Richard;

    2012-01-01

    Advances in proteomics are continually driven by the introduction of new mass spectrometric instrumentation with improved performances. The recently introduced quadrupole Orbitrap (Q Exactive) tandem mass spectrometer allows fast acquisition of high-resolution higher-energy collisional dissociation...

  19. The winding and testing of a 10 cm superconductive quadrupole for CERN

    CERN Document Server

    Williams, J.E.C.; Cornish, D.N.

    1970-01-01

    The construction and testing of the first of a pair of quadrupole magnets, designed for use as superconductive beam handling elements at CERN, is described. Tests showed this magnet to be eminently suitable for nuclear physics applications.

  20. High-precision quadrupole moment reveals significant intruder component in 20 13 33Al ground state

    Science.gov (United States)

    Heylen, H.; De Rydt, M.; Neyens, G.; Bissell, M. L.; Caceres, L.; Chevrier, R.; Daugas, J. M.; Ichikawa, Y.; Ishibashi, Y.; Kamalou, O.; Mertzimekis, T. J.; Morel, P.; Papuga, J.; Poves, A.; Rajabali, M. M.; Stödel, C.; Thomas, J. C.; Ueno, H.; Utsuno, Y.; Yoshida, N.; Yoshimi, A.

    2016-09-01

    The electric quadrupole moment of the 20 13 33Al ground state, located at the border of the island of inversion, was obtained using continuous-beam β -detected nuclear quadrupole resonance (β -NQR). From the measured quadrupole coupling constant νQ=2.31 (4 ) MHz in an α -Al2O3 crystal, a precise value for the electric quadrupole moment is extracted: 33Al>Qs 141 (3 ) mb. A comparison with large-scale shell model calculations shows that 33Al has at least 50% intruder configurations in the ground state wave function, favoring the excitation of two neutrons across the N =20 shell gap. 33Al therefore clearly marks the gradual transition north of the deformed Na and Mg nuclei towards the normal Z ≥14 isotopes.

  1. High-precision quadrupole moment reveals significant intruder component in 33Al20 ground state

    CERN Document Server

    Heylen, H; Neyens, G; Bissell, M L; Caceres, L; Chevrier, R; Daugas, J M; Ichikawa, Y; Ishibashi, Y; Kamalou, O; Mertzimekis, T J; Morel, P; Papuga, J; Poves, A; Rajabali, M M; Stodel, C; Thomas, J C; Ueno, H; Utsuno, Y; Yoshida, N; Yoshimi, A

    2016-01-01

    The electric quadrupole moment of the 33Al20 ground state, located at the border of the island of inversion, was obtained using continuous-beam beta-detected nuclear quadrupole resonance (beta-NQR). From the measured quadrupole coupling constant Q = 2.31(4) MHz in an alpha-Al2O3 crystal, a precise value for the electric quadrupole moment is extracted: Qs= 141(3) mb. A comparison with large-scale shell model calculations shows that 33Al has at least 50% intruder configurations in the ground state wave function, favoring the excitation of two neutrons across the N = 20 shell gap. 33Al therefore clearly marks the gradual transition north of the deformed Na and Mg nuclei towards the normal Z>14 isotopes.

  2. Nuclear electric quadrupole moment of 9Li using zero-field β-detected NQR

    Science.gov (United States)

    Voss, A.; Pearson, M. R.; Billowes, J.; Buchinger, F.; Chow, K. H.; Crawford, J. E.; Hossein, M. D.; Kiefl, R. F.; Levy, C. D. P.; MacFarlane, W. A.; Mané, E.; Morris, G. D.; Parolin, T. J.; Saadaoui, H.; Salman, Z.; Smadella, M.; Song, Q.; Wang, D.

    2011-07-01

    A β-detected nuclear quadrupole resonance (NQR) spectrometer becomes a powerful tool to study changes in nuclear ground-state properties along isotopic chains when coupled to a laser excitation beamline to polarize the nuclei of interest. Recently, the β-NQR technique in a zero magnetic field has been applied for the first time to measure the ratio of static nuclear quadrupole moments of 8, 9Li, Q9/Q8 = 0.966 75(9) denoted by Q8 for 8Li and Q9 for 9Li, respectively. This shows agreement with present literature values but with significantly improved precision. Based on the literature, the quadrupole moment for 8Li has been re-evaluated to be |Q8| = 32.6(5) mb. From this, the quadrupole moment for 9Li is calculated as |Q9| = 31.5(5) mb with the error being dominated by the error of Q8.

  3. Microscopic derivation of the Bohr-Mottelson collective Hamiltonian and its application to quadrupole shape dynamics

    CERN Document Server

    Matsuyanagi, Kenichi; Nakatsukasa, Takashi; Yoshida, Kenichi; Hinohara, Nobuo; Sato, Koichi

    2016-01-01

    We discuss the nature of the low-frequency quadrupole vibrations from small-amplitude to large-amplitude regimes. We consider full five-dimensional quadrupole dynamics including three-dimensional rotations restoring the broken symmetries as well as axially symmetric and asymmetric shape fluctuations. Assuming that the time-evolution of the self-consistent mean field is determined by five pairs of collective coordinates and collective momenta, we microscopically derive the collective Hamiltonian of Bohr and Mottelson, which describes low-frequency quadrupole dynamics. We show that the five-dimensional collective Schr\\"odinger equation is capable of describing large-amplitude quadrupole shape dynamics seen as shape coexistence/mixing phenomena. We summarize the modern concepts of microscopic theory of large-amplitude collective motion, which is underlying the microscopic derivation of the Bohr-Mottelson collective Hamiltonian.

  4. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  5. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available effect was observed for the elongation at break of the hybrid composites. The impact strength of the hybrid composites increased with the addition of glass fibres. The tensile and impact properties of thermoplastic natural rubber reinforced short... panels made from conventional structural materials. Figure 3 illustrates the performance of cellular biocomposite panels against conventional systems used for building and residential construction, namely a pre- cast pre-stressed hollow core concrete...

  6. A summary of the quench behavior of B&W 1 m collider quadrupole model magnets

    Energy Technology Data Exchange (ETDEWEB)

    Rey, C.M.; Xu, M.F.; Hlasnicek, P.; Kelley, J.P.; Dixon, K.; Savignano, J.; Letterman, S.; Craig, P.; Maloney, J.; Boyes, D. [Babcock & Wilcox, Lynchburg, VA (United States)] [and others

    1994-12-31

    In order to evaluate the quench performance of a B&W-Siemens designed quadrupole magnet at the earliest possible stage, a model magnet program was developed at B&W for the support of the Superconducting Super Collider. The authors report the quench performance, training behavior, and the ramp rate dependence for the QSH-801 through QSH-804 series of short (1.2 meter) quadrupole model magnets.

  7. Performance of Nb3Sn quadrupole magnets under localized thermal load

    Energy Technology Data Exchange (ETDEWEB)

    Kashikhin, V.V.; Bossert, r.; Chlachidze, G.; Lamm, M.; Mokhov, N.V.; Novitski, I.; Zlobin, A.V.; /Fermilab

    2009-06-01

    This paper describes the results of design and analyses performed on 120-mm Nb{sub 3}Sn and NbTi quadrupole magnets with parameters relevant for the LHC IR upgrade. A realistic radiation heat load is evaluated in a wide luminosity range and translated into the magnet quench performance. The simulation results are supported by thermal measurements on a 90-mm Nb{sub 3}Sn quadrupole coil.

  8. Superconducting Quadrupole for the ISR High Luminosity insertion:end view

    CERN Multimedia

    1977-01-01

    Connection end view of the prototype quadrupole before insertion of the inner vacuum chamber with inbedded 6-pole windings. The main components of the structure can be seen: (from inside outwards) the superconducting quadrupole coils surrounded by glass epoxy bandage rings and stainless steel spacers, the low-carbon steel yoke quadrants and the aluminium alloy shrinking rings. See also photos 7702690X, 7702307, 7702308, 7812604X.

  9. Assembly of the first model of MQXFS quadrupole magnet for Hi-Lumi

    CERN Multimedia

    AUTHOR|(CDS)2086825

    2016-01-01

    Building 927. Assembly of the first model of MQXFS quadrupole magnet for Hi-Lumi. The MQXF models are about 1.5 m long and are used to validate the design before start building the first long prototype. Two types of insertion quadrupoles will be built and installed in the LHC tunnel during LS3. LARP (US collaboration) will built MQXFA type (4.2 meters long) and MQXFB magnets (around 7 m long) will be built at CERN.

  10. Design report of the QTG quadrupoles for the CERN CNGS line

    CERN Document Server

    Zickler, T

    2000-01-01

    This report presents the actual QTG design. The quadrupole magnets are part of the "CERN Neutrino to Gran Sasso" transfer line TT40. The design is optimized for a nominal beam energy of 400 GeV. The quadrupoles are resistive iron-dominated magnets with a gradient of 40 T/m and an inscribed radius of 22.5 mm. The 2200 mm long yokes will be built form low carbon steel laminations stacked between non-laminated end plates.

  11. Design and measurements of a thin quadrupole magnet for the AGS synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Tsoupas, N., E-mail: tsoupas@bnl.go [Brookhaven National Laboratory BNL, Upton, NY 11973 (United States); Alforque, R.; Jain, A.; MacKay, W.; Marneris, I. [Brookhaven National Laboratory BNL, Upton, NY 11973 (United States)

    2011-03-21

    Four quadrupoles were installed in four straight sections of the AGS synchrotron to compensate for the effect on the beam optics of two helical magnets also installed in the AGS. The overall length of each quadrupole is less than 30 cm, so it fits in the 62 cm long straight section of the AGS ring. At injection energies, the strength of each quadrupole is set at a high value, and is ramped down to zero during the acceleration cycle, as the effect of the helical magnets on the circulating beam, diminishes by the square of the beam's rigidity. To minimize the eddy currents generated in the iron core of the quadrupole, by the transient magnetic field during the ramp down time, the quadrupoles were laminated. In this paper we describe the process of designing the quadrupole, with three of the most important aspects of the design discussed below. The first was to select the maximum thickness of the iron lamination that does not affect significantly the field quality of the quadrupole during the ramp down time interval, and also reduces to an acceptable level the ohmic losses generated in the iron laminations. The second was to minimize the higher order, 12pole allowed magnetic multipole of the quadrupole. The third was to calculate the ohmic losses in the iron laminations, as a function of both the lamination thickness and the magnetic field strength. The calculated ohmic losses in the iron laminations as a function of time and lamination thickness are consistent with the time evolution of the eddy currents inside the laminations. Simple experimental measurement of the current and voltage across the coil of the magnet as a function of time, qualitatively agrees with the theoretically calculated ohmic losses in the iron laminations.

  12. Negative coupling and coupling phase dispersion in a silicon quadrupole micro-racetrack resonator.

    Science.gov (United States)

    Bachman, Daniel; Tsay, Alan; Van, Vien

    2015-07-27

    We report the first experimental study of the effects of coupling phase dispersion on the spectral response of a two-dimensionally coupled quadrupole micro-racetrack resonator. Negative coupling in the system is observed to manifest itself in the sharp stop band transition and deep extinction in the pseudo-elliptic filter response of the quadrupole. The results demonstrate the feasibility of realizing advanced silicon microring devices based on the 2D coupling topology with general complex coupling coefficients.

  13. Performance of Nb3Sn quadrupole magnets under localized thermal load

    Energy Technology Data Exchange (ETDEWEB)

    Kashikhin, V.V.; Bossert, r.; Chlachidze, G.; Lamm, M.; Mokhov, N.V.; Novitski, I.; Zlobin, A.V.; /Fermilab

    2009-06-01

    This paper describes the results of design and analyses performed on 120-mm Nb{sub 3}Sn and NbTi quadrupole magnets with parameters relevant for the LHC IR upgrade. A realistic radiation heat load is evaluated in a wide luminosity range and translated into the magnet quench performance. The simulation results are supported by thermal measurements on a 90-mm Nb{sub 3}Sn quadrupole coil.

  14. Lie algebraic analysis for the nonlinear transport of intense bunched beam in electrostatic quadrupoles

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhuo; L(U) Jian-Qin

    2008-01-01

    In this paper, the nonlinear transport of intense bunched beams in electrostatic quadrupoles is analyzed using the Lie algebraic method, and the results are briefly presented of the linear matrix approximation and the second order correction of particle trajectory in the state space. Beam having K-V distribution and Gaussian distribution approximation are respectively considered. A brief discussion is also given of the total effects of the quadrupole and the space charge forces on the evolution of the beam envelope.

  15. Effect of the Quadrupole Moment of a Rotating Massive Object on the Gravitational Faraday Rotation

    Institute of Scientific and Technical Information of China (English)

    陈贻汉; 邵常贵

    2002-01-01

    We study the rotation of the polarization plane for a ray of electromagnetic radiation propagating in the grav-itoelectromagnetic field caused by a rotating massive object with the quadrupole moment. The effect of thequadrupole moment on the gravitational Faraday rotation is investigated. It is found that the gravitational Fara-day effect of the quadrupole moment is negligible for Kerr black holes, but this effect is important for rapidlyrotating neutron stars.

  16. Design Challenges for a Wide-Aperture Insertion Quadrupole Magnet

    CERN Document Server

    Russenschuck, S; Perez, J C; Ramos, D; Fessia, P; Karppinen, M; Kirby, G; Sahner, T; Schwerg, N

    2011-01-01

    The design and development of a superconducting (Nb-Ti) quadrupole with 120 mm aperture, for an upgrade of the LHC insertion region, faces challenges arising from the LHC beam optics requirements and the heat-deposition. The first triggered extensive studies of coil alternatives with four and six coil-blocks in view of field quality and operation margins. The latter requires more porous insulation schemes for both the cables and the ground-plane. This in turn necessitates extensive heatpropagation and quench-velocity studies, as well as more efficient quench heaters. The engineering design of the magnet includes innovative features such as self-locking collars, which will enable the collaring to be performed with the coils on a horizontal assembly bench, a spring-loaded and collapsible assembly mandrel, tuning-shims for field quality, porous collaring-shoes, and coil end-spacer design based on differential geometry methods. The project also initiated code extensions in the quench-simulation and CAD/CAM module...

  17. Newly developed apparatus for calibration of quadrupole mass spectrometer

    Science.gov (United States)

    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.

  18. Modal response of 4-rod type radio frequency quadrupole linac

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, Avik; Mahapatra, Abhijit [Central Mechanical Engineering Research Institute (CMERI), M.G. Avenue, Durgapur 713209 (India); Mondal, Manas; Chakrabarti, Alok [Variable Energy Cyclotron Centre (VECC), Sector-1/AF, Bidhannagar, Kolkata 700064 (India)

    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.

  19. Spin dipole and quadrupole resonances in sup 40 Ca

    Energy Technology Data Exchange (ETDEWEB)

    Baker, F.T.; Love, W.G. (The University of Georgia, Athens, GA (USA)); Bimbot, L. (The University of Paris, Orsay, (France)); Fergerson, R.W.; Glashausser, C.; Green, A. (Rutgers University, New Brunswick, NJ (USA)); Jones, K. (Los Alamos National Laboratory, Los Alamos, NM (USA)); Nanda, S. (Continuous Electron Beam Accelerator Facility, Newport News, VA (USA) The University of Georgia, Athens, GA (USA))

    1989-11-01

    Angular distributions of the double differential cross section {ital d}{sup 2}{sigma}/d{Omega} dE({sigma}) and the spin-flip probability {ital S}{sub {ital nn}} have been measured for inclusive proton inelastic scattering from {sup 40}Ca at 319 MeV. Excitation energies ({omega}) up to about 40 MeV have been investigated over the angular range from 3.5{degree} to 12{degree} in the laboratory (0.3 to 0.9 fm{sup {minus}1}). Here, multipole decompositions of angular distributions of {sigma}{ital S}{sub {ital nn}} for the {sup 40}Ca({ital {rvec p}},{ital {rvec p}} {prime}) reaction at 319 MeV have been performed in order to compare {Delta}{ital S}=1 strength observed with sum rules. In contrast to the well-known quenching of Gamow-Teller and {ital M}1 resonances, the spin-dipole resonance has a total measured strength which is larger than that predicted by the energy-weighted sum rule. The spin-dipole strength distribution supports asymmetric widths predicted by calculations including 2p-2h mixing. The spin-quadrupole resonance is observed near {omega}=35 MeV and its total strength for {omega}{lt}40 MeV estimated.

  20. Polarization enhanced Nuclear Quadrupole Resonance with an atomic magnetometer

    Science.gov (United States)

    Malone, Michael W.; Barrall, Geoffrey A.; Espy, Michelle A.; Monti, Mark C.; Alexson, Dimitri A.; Okamitsu, Jeffrey K.

    2016-05-01

    Nuclear Quadrupole Resonance (NQR) has been demonstrated for the detection of 14-N in explosive compounds. Application of a material specific radio-frequency (RF) pulse excites a response typically detected with a wire- wound antenna. NQR is non-contact and material specific, however fields produced by NQR are typically very weak, making demonstration of practical utility challenging. For certain materials, the NQR signal can be increased by transferring polarization from hydrogen nuclei to nitrogen nuclei using external magnetic fields. This polarization enhancement (PE) can enhance the NQR signal by an order of magnitude or more. Atomic magnetometers (AM) have been shown to improve detection sensitivity beyond a conventional antenna by a similar amount. AM sensors are immune to piezo-electric effects that hamper conventional NQR, and can be combined to form a gradiometer for effective RF noise cancellation. In principle, combining polarization enhancement with atomic magnetometer detection should yield improvement in signal-to-noise ratio that is the product of the two methods, 100-fold or more over conventional NQR. However both methods are even more exotic than traditional NQR, and have never been combined due to challenges in operating a large magnetic field and ultra-sensitive magnetic field sensor in proximity. Here we present NQR with and without PE with an atomic magnetometer, demonstrating signal enhancement greater than 20-fold for ammonium nitrate. We also demonstrate PE for PETN using a traditional coil for detection with an enhancement factor of 10. Experimental methods and future applications are discussed.

  1. On the formation of the South Pacific quadrupole mode

    Science.gov (United States)

    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.

  2. A Graphical Approach to Radio Frequency Quadrupole Design

    CERN Document Server

    Turemen, G; Yasatekin, B

    2014-01-01

    The design of a radio frequency quadrupole, an important section of all ion accelerators, and the calculation of its beam dynamics properties can be achieved using the existing computational tools. These programs, originally designed in 1980s, show effects of aging in their user interfaces and in their output. The authors believe there is room for improvement in both design techniques using a graphical approach and in the amount of analytical calculations before going into CPU burning finite element analysis techniques. Additionally an emphasis on the graphical method of controlling the evolution of the relevant parameters using the drag-to-change paradigm is bound to be beneficial to the designer. A computer code, named DEMIRCI, has been written in C++ to demonstrate these ideas. This tool has been used in the design of Turkish Atomic Energy Authority (TAEK)'s 1.5 MeV proton beamline at Saraykoy Nuclear Research and Training Center (SANAEM). DEMIRCI starts with a simple analytical model, calculates the RFQ b...

  3. Coupled gas and ion transport in quadrupole interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Jugroot, M [Institute for Aerospace Studies, University of Toronto, Ontario, M3H 5T6 (Canada); Groth, C P T [Institute for Aerospace Studies, University of Toronto, Ontario, M3H 5T6 (Canada); Thomson, B A [MDS SCIEX, Concord, Ontario, L4K 4V8 (Canada); Baranov, V [MDS SCIEX, Concord, Ontario, L4K 4V8 (Canada); Collings, B A [MDS SCIEX, Concord, Ontario, L4K 4V8 (Canada); French, J B [MDS SCIEX, Concord, Ontario, L4K 4V8 (Canada)

    2008-01-21

    The transport of free ions through highly under-expanded jet flows of neutral gases and in the presence of applied electric fields is investigated by continuum-based (fluid) numerical simulations. In particular, numerical results are described which are relevant to ion flows occurring in quadrupole interfaces of mass spectrometer systems. A five-moment mathematical model and parallel multi-block numerical solution procedure are developed for predicting the ion transport. The model incorporates the effects of ion-neutral collision processes and is used in conjunction with a Navier-Stokes model and flow solver for the neutral gas to examine the key influences controlling the ion motion. The effects of the neutral gas flow, electric fields (both dc and rf) and flow field geometry on ion mobility are carefully assessed. The capability of controlling the charged particle motions through a combination of directed neutral flow and applied electric field is demonstrated for these high-speed, hypersonic, jet flows. The neutral dynamics is shown to have a strong influence on the ion transport whereas the electric field imparts a more gradual effect. The combined effect of the applied (dc and rf) electric field and neutral collision processes with the dilute neutral gas results in a strong tendency for ion focusing towards the axis of symmetry, with the overall efficiency governed by the mass-to-charge ratio.

  4. Two-dimensional Nutation Echo Nuclear Quadrupole Resonance Spectroscopy

    Science.gov (United States)

    Harbison, Gerard S.; Slokenbergs, Andris

    1990-04-01

    We discuss two new two-dimensional nuclear quadrupole resonance experiments, both based on the principle of nutation spectroscopy, which can be used to determine the asymmetry parameter, and thus the full quadrupolar tensor, of spin-3/2 nuclei at zero applied magnetic field. The first experiment is a simple nutation pulse sequence in which the first time period (t1) is the duration of the radiofrequency exciting pulse; and the second (t2) is the normal free-precession of a quadrupolar nucleus at zero-field. After double Fourier-transformation, the result is a 2 D spectrum in which the first frequency dimension is the nutation spectrum for the quadrupolar nucleus at zero-field. For polycrystalline samples this sequence generates powder lineshapes; the position of the singularities, in these lineshapes can be used to determine the asymmetry parameters η in a very straightforward manner, η has previously only been obtainable using Zeeman perturbed NQR methods. The second sequence is the same nutation experiment with a spin-echo pulse added. The virtue of this refocussing pulse is that it allows acquisition of nutation spectra from samples with arbitrary inhomogeneous linewidth; thus, asymmetry parameters can be determined even where the quadrupolar resonance is wider than the bandwidth of the spectrometer. Experimental examples of 35Cl, 81Br and 63Cu nutation and nutation-echo spectra are presented.

  5. A versatile computer-controlled pulsed nuclear quadrupole resonance spectrometer

    Science.gov (United States)

    Fisher, Gregory; MacNamara, Ernesto; Santini, Robert E.; Raftery, Daniel

    1999-12-01

    A new, pulsed nuclear quadrupole resonance (NQR) spectrometer capable of performing a variety of pulsed and swept experiments is described. The spectrometer features phase locked, superheterodyne detection using a commercial spectrum analyzer and a fully automatic, computer-controlled tuning and matching network. The tuning and matching network employs stepper motors which turn high power air gap capacitors in a "moving grid" optimization strategy to minimize the reflected power from a directional coupler. In the duplexer circuit, digitally controlled relays are used to switch different lengths of coax cable appropriate for the different radio frequencies. A home-built pulse programmer card controls the timing of radio frequency pulses sent to the probe, while data acquisition and control software is written in Microsoft Quick Basic. Spin-echo acquisition experiments are typically used to acquire the data, although a variety of pulse sequences can be employed. Scan times range from one to several hours depending upon the step resolution and the spectral range required for each experiment. Pure NQR spectra of NaNO2 and 3-aminopyridine are discussed.

  6. Identification of Transient and Permanent Faults

    Institute of Scientific and Technical Information of China (English)

    李幼仪; 董新洲; 孙元章

    2003-01-01

    A new algorithm was developed for arcing fault detection based on high-frequency current transients analyzed with wavelet transforms to avoid automatic reclosing on permanent faults. The characteristics of arc currents during transient faults were investigated. The current curves of transient and permanent faults are quite similar since current variation from the fault arc is much less than the voltage variation. However, the fault current details are quite different because of the arc extinguishing and reigniting. Dyadic wavelet transforms were used to identify the current variation since wavelet transform has time-frequency localization ability. Many electric magnetic transient program (EMTP) simulations have verified the feasibility of the algorithm.

  7. Permanent isolation surface barrier: Functional performance

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1993-10-01

    This document presents the functional performance parameters for permanent isolation surface barriers. Permanent isolation surface barriers have been proposed for use at the Hanford Site (and elsewhere) to isolate and dispose of certain types of waste in place. Much of the waste that would be disposed of using in-place isolation techniques is located in subsurface structures, such as solid waste burial grounds, tanks, vaults, and cribs. Unless protected in some way, the wastes could be transported to the accessible environment via transport pathways, such as water infiltration, biointrusion, wind and water erosion, human interference, and/or gaseous release.

  8. Treatment of ectopic first permanent molar teeth.

    LENUS (Irish Health Repository)

    Hennessy, Joe

    2012-11-01

    Ectopic eruption of the first permanent molar is a relatively common occurence in the developing dentition. A range of treatment options are available to the clinician provided that diagnosis is made early. Non-treatment can result in premature exfoliation of the second primary molar, space loss and impaction of the second premolar. This paper will describe the management of ectopic first permanent molars, using clinical examples to illustrate the available treatment options. CLINICAL RELEVANCE: This paper is relevant to every general dental practitioner who treats patients in mixed dentition.

  9. Design and construction of permanent magnetic gears

    OpenAIRE

    Jørgensen, Frank Thorleif

    2010-01-01

    This thesis deals with design and development of permanent magnetic gears. The goal of this thesis is to develop knowledge and calculation software for magnetic gears. They use strong NdFeB permanent magnets and a new magnetic gear technology, which will be a serious alternative to classical mechanical gears. The new magnetic gear will have a high torque density1 relationship –high efficiency and are maintenance free. In this project was manufactured two test gears which is tested and verifie...

  10. A toroidal trap for the cold $^{87}Rb$ atoms using a rf-dressed quadrupole trap

    CERN Document Server

    Chakraborty, A; Ram, S P; Tiwari, S K; Rawat, H S

    2015-01-01

    We demonstrate the trapping of cold $^{87}Rb$ atoms in a toroidal geometry using a rf-dressed quadrupole magnetic trap formed by superposing a strong radio frequency (rf) field on a quadrupole trap. This rf-dressed quadrupole trap has minimum of the potential away from the quadrupole trap centre on a circular path which facilitates the trapping in the toroidal geometry. In the experiments, the laser cooled atoms were first trapped in the quadrupole trap, then cooled evaporatively using a weak rf-field, and finally trapped in the rf-dressed quadrupole trap. The radius of the toroid could be varied by varying the frequency of the dressing rf-field. It has also been demonstrated that a single rf source and an antenna can be used for the rf-evaporative cooling as well as for rf-dressing of atoms. The atoms trapped in the toroidal trap may have applications in realization of an atom gyroscope as well as in studying the quantum gases in low dimensions.

  11. High-Performance Permanent Magnets for Energy-Efficient Devices

    Science.gov (United States)

    Hadjipanayis, George

    2012-02-01

    Permanent magnets (PMs) are indispensable for many commercial applications including the electric, electronic and automobile industries, communications, information technologies and automatic control engineering. In most of these applications, an increase in the magnetic energy density of the PM, usually presented via the maximum energy product (BH)max, immediately increases the efficiency of the whole device and makes it smaller and lighter. Worldwide demand for high performance permanent magnets has increased dramatically in the past few years driven by hybrid and electric cars, wind turbines and other power generation systems. New energy challenges in the world require devices with higher energy efficiency and minimum environmental impact. The potential of 3d-4f compounds which revolutionized the PM science and technology is almost fully utilized, and the supply of 4f rare earth elements does not seem to be much longer assured. This talk will address the major principles guiding the development of PMs and overview state-of-the-art theoretical and experimental research. Recent progress in the development of nanocomposite PMs, consisting of a fine (at the scale of the magnetic exchange length) mixture of phases with high magnetization and large magnetic hardness will be discussed. Fabrication of such PMs is currently the most promising way to boost the (BH)max, while simultaneously decreasing, at least partially, the reliance on the rare earth elements. Special attention will be paid to the impact which the next-generation high-(BH)max magnets is expected to have on existing and proposed energy-saving technologies.

  12. PROCEDURE FOR ESTIMATING PERMANENT TOTAL ENCLOSURE COSTS

    Science.gov (United States)

    The paper discusses a procedure for estimating permanent total enclosure (PTE) costs. (NOTE: Industries that use add-on control devices must adequately capture emissions before delivering them to the control device. One way to capture emissions is to use PTEs, enclosures that mee...

  13. SNO expanded and given permanent status

    CERN Multimedia

    2003-01-01

    The Sudbury Neutrino Observatory (SNO) is being transformed into a permanent international research facility with the assistance of the Canada Foundation for Innovation's International Access Fund. The CFI is providing $38.9 million to establish the new International Facility for Underground Science (1/2 page).

  14. Lowering the Permanent Rate of Unemployment.

    Science.gov (United States)

    Feldstein, Martin S.

    The first section of the study on lowering the permanent rate of unemployment discusses the effects and limitations of increasing aggregate demand through fiscal and monetary policy and indicates the inability to achieve the desired level of unemployment simply by stimulating demand. Section 2 analyzes the characteristics and structure of our…

  15. Permanent magnet motor technology design and applications

    CERN Document Server

    Gieras, Jacek F

    2009-01-01

    Demonstrates the construction of permanent magnet (PM) motor drives and supplies ready-to-implement solutions to common roadblocks along the way. This book also supplies fundamental equations and calculations for determining and evaluating system performance, efficiency, reliability, and cost. It explores modern computer-aided design of PM motors.

  16. Dovetail spoke internal permanent magnet machine

    Science.gov (United States)

    Alexander, James Pellegrino; EL-Refaie, Ayman Mohamed Fawzi; Lokhandwalla, Murtuza; Shah, Manoj Ramprasad; VanDam, Jeremy Daniel

    2011-08-23

    An internal permanent magnet (IPM) machine is provided. The IPM machine includes a stator assembly and a stator core. The stator core also includes multiple stator teeth. The stator assembly is further configured with stator windings to generate a stator magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface defining a cavity. The IPM machine also includes a rotor assembly and a rotor core. The rotor core is disposed inside the cavity and configured to rotate about the longitudinal axis. The rotor assembly further includes a shaft. The shaft further includes multiple protrusions alternately arranged relative to multiple bottom structures provided on the shaft. The rotor assembly also includes multiple stacks of laminations disposed on the protrusions and dovetailed circumferentially around the shaft. The rotor assembly further includes multiple pair of permanent magnets for generating a magnetic field, which magnetic field interacts with the stator magnetic field to produce a torque. The multiple pair of permanent magnets are disposed between the stacks. The rotor assembly also includes multiple middle wedges mounted between each pair of the multiple permanent magnets.

  17. Permanent downhole seismic sensors in flowing wells

    NARCIS (Netherlands)

    Jaques, P.; Ong, H.; Jupe, A.; Brown, I.; Jansenns, M.

    2003-01-01

    It is generally accepted that the 'Oilfield of the Future' will incorporate distributed permanent downhole seismic sensors in flowing wells. However the effectiveness of these sensors will be limited by the extent to which seismic signals can be discriminated, or de-coupled, from flow induced

  18. Permanent female mimics in a lekking shorebird

    NARCIS (Netherlands)

    Jukema, Joop; Piersma, Theunis

    2006-01-01

    Female mimics are known from many species, but permanent, non-conditional, alternative mating strategies are only known from an isopod, a fish, a lizard and a bird. The single bird example refers to lek-breeding ruffs Philomachus pugnax, a shorebird for which two strategies (independent and satellit

  19. Permanent isolation surface barrier development plan

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1994-01-01

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no {open_quotes}proven{close_quotes} long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems.

  20. The physics of quadrupole interactions in crystals. Quadrupole interactions observed in the 1{sup +} {yields} 0{sup +}{gamma}-ray transition

    Energy Technology Data Exchange (ETDEWEB)

    Goldting, G. [Weizmann Inst. of Science, Rehovoth (Israel); Anderssen, S.S.; Lane, G.J. [Australian National Univ., Canberra, ACT (Australia). Research School of Physical Sciences

    1995-11-01

    For many people the nuclear interaction with the electric quadrupole is not as easily understood as the magnetic dipole interaction. This is partly due to the use of Racah algebra in conventional quadrupole interaction calculations. Although this is a powerful technique that provides a neat summation over the m-substates of both the initial nuclear state and the emitted radiation, the formalism does tend to `hide` some of the details and interesting features of the interaction. Therefore, to improve our understanding of these processes with an emphasis on the physical characteristics, these notes will detail the calculation of quadrupole interactions with both polarised and aligned nuclei without using Racah algebra. To make these calculations manageable only the 1{sup +}{yields} 0{sup +}{gamma}-ray transition is considered. The J{sup {pi}} =1{sup +} state has only 3 substates (m = -1,0,+1), and the parity and angular momentum selection rules allow only M1 magnetic dipole transitions. The calculation has led to some explanations of the difference between the aligned and polarized quadrupole interactions, which is the orientation of the quantization axis with respect to the equatorial plane.

  1. Detecting body cavity bombs with nuclear quadrupole resonance

    Science.gov (United States)

    Collins, Michael London

    Nuclear Quadrupole Resonance (NQR) is a technology with great potential for detecting hidden explosives. Past NQR research has studied the detection of land mines and bombs concealed within luggage and packages. This thesis focuses on an NQR application that has received less attention and little or no publicly available research: detecting body cavity bombs (BCBs). BCBs include explosives that have been ingested, inserted into orifices, or surgically implanted. BCBs present a threat to aviation and secure facilities. They are extremely difficult to detect with the technology currently employed at security checkpoints. To evaluate whether or not NQR can be used to detect BCBs, a computational model is developed to assess how the dielectric properties of biological tissue affect the radio frequency magnetic field employed in NQR (0.5-5MHz). The relative permittivity of some biological tissue is very high (over 1,000 at 1MHz), making it conceivable that there is a significant effect on the electromagnetic field. To study this effect, the low-frequency approximation known as the Darwin model is employed. First, the electromagnetic field of a coil is calculated in free space. Second, a dielectric object or set of objects is introduced, and the free-space electric field is modified to accommodate the dielectric object ensuring that the relevant boundary conditions are obeyed. Finally, the magnetic field associated with the corrected electric field is calculated. This corrected magnetic field is evaluated with an NQR simulation to estimate the impact of dielectric tissue on NQR measurements. The effect of dielectric tissue is shown to be small, thus obviating a potential barrier to BCB detection. The NQR model presented may assist those designing excitation and detection coils for NQR. Some general coil design considerations and strategies are discussed.

  2. Efficient IEC permanent magnet motor; Effizienter IEC Permanent-Magnetmotor (3 kW) - Jahresbericht 2007

    Energy Technology Data Exchange (ETDEWEB)

    Lindegger, M.; Salathe, D.; Biner, H. P.; Evequoz, B.

    2007-07-01

    This annual report for the Swiss Federal Office of Energy (SFOE) takes a look at the work done at the Swiss Universities of Applied Sciences in Lucerne and Valais and the Circle Motor Company in 2007 on the economic feasibility, efficiency and limitations of permanent magnet motors. The higher efficiency of permanent-magnet motors in comparison with asynchronous motors for powers of over 100 kW is noted. Work done on the integration of a 3 kW permanent-magnet motor in an IEC-Standard housing is described. The construction of an efficient permanent magnet motor drive and its testing at the Valais University of Applied Sciences is discussed. The high efficiencies obtained both for the motor and its drive electronics are noted.

  3. Drive Beam Quadrupoles for the CLIC Project: a Novel Method of Fiducialisation and a New Micrometric Adjustment System

    CERN Document Server

    AUTHOR|(SzGeCERN)411678; Duquenne, Mathieu; Sandomierski, Jacek; Sosin, Mateusz; Rude, Vivien

    2014-01-01

    This paper presents a new method of fiducialisation applied to determine the magnetic axis of the Drive Beam quadrupole of the CLIC project with respect to external alignment fiducials, within a micrometric accuracy and precision. It introduces also a new micrometric adjustment system along 5 Degrees of Freedom, developed for the same Drive Beam quadrupole. The combination of both developments opens very interesting perspectives to get a more simple and accurate alignment of the quadrupoles.

  4. Marine genetic swamping: hybrids replace an obligately estuarine fish.

    Science.gov (United States)

    Roberts, David G; Gray, Charles A; West, Ronald J; Ayre, David J

    2010-02-01

    Populations of obligately estuarine taxa are potentially small and isolated and may lack genetic variation and display regional differentiation as a result of drift and inbreeding. Hybridization with a wide-ranging marine congener should introduce genetic variation and reduce the effects of inbreeding depression and genetic drift. However, high levels of hybridization can cause demographic and genetic swamping. In southeastern Australia hybridization occurs between obligately estuarine Black bream (Acanthopagrus butcheri) and migratory marine Yellowfin bream (Acanthopagrus australis). Here, we surveyed genetic variation at eight microsatellite loci and the mitochondrial control region of juvenile fish from five coastal lagoons (including temporal replication in two lagoons) (total n = 970) to determine the frequency and persistence of hybridization, and its likely consequence for the estuarine restricted A. butcheri. Of 688 juvenile fish genotyped 95% were either A. australis (347) or hybrids (309); only 5% (32) were A. butcheri. Most hybrids were later generation hybrids or A. butcheri backcrosses, which are likely multi-generational residents within lagoons. Far greater proportions of hybrid juveniles were found within two lagoons that are generally closed to the ocean (>90% hybrid fish within generally closed lagoons vs. 12-27% in permanently or intermittently open lagoons). In both lagoons, this was consistent across multiple cohorts of fish [79-97% hybrid fish (n = 282)]. Hybridization and introgression represent a major threat to the persistence of A. butcheri and have yet to be investigated for large numbers of estuarine taxa.

  5. Design and construction of permanent magnetic gears

    DEFF Research Database (Denmark)

    Jørgensen, Frank Thorleif

    This thesis deals with design and development of permanent magnetic gears. The goal of this thesis is to develop knowledge and calculation software for magnetic gears. They use strong NdFeB permanent magnets and a new magnetic gear technology, which will be a serious alternative to classical...... calculation models for determination of gear output torque from different magnetic gear types are analysed. These analytical calculations models are used together with optimisation tools in order to improve the performance of investigated magnetic gear types. Experimental test gears are designed to validate...... is searched and only a single reference [74] is found and that is why the combination of a cycloidal gear and a magnetic gear are considered as an innovative supplement to magnetic gear technology. A magnetic cycloidal gear is designed with a gearing of 1:21 and a calculated active torque density of 142 [Nm...

  6. Permanence and Community Structure in Complex Networks

    CERN Document Server

    Chakraborty, Tanmoy; Ganguly, Niloy; Mukherjee, Animesh; Bhowmick, Sanjukta

    2016-01-01

    The goal of community detection algorithms is to identify densely-connected units within large networks. An implicit assumption is that all the constituent nodes belong equally to their associated community. However, some nodes are more important in the community than others. To date, efforts have been primarily driven to identify communities as a whole, rather than understanding to what extent an individual node belongs to its community. Therefore, most metrics for evaluating communities, for example modularity, are global. These metrics produce a score for each community, not for each individual node. In this paper, we argue that the belongingness of nodes in a community is not uniform. The central idea of permanence is based on the observation that the strength of membership of a vertex to a community depends upon two factors: (i) the the extent of connections of the vertex within its community versus outside its community, and (ii) how tightly the vertex is connected internally. We discuss how permanence ...

  7. Sensorless Control of Permanent Magnet Synchronous Machines

    DEFF Research Database (Denmark)

    Matzen, Torben N.

    Permanent magnet machines, with either surface mounted or embedded magnets on the rotor, are becoming more common due to the key advantages of higher energy conversion efficiency and higher torque density compared to the classical induction machine. Besides energy efficiency the permanent magnet...... are dependent on the phase currents and rotor position. Based on the flux linkages the differential inductances are determined and used to establish the inductance saliency in terms of ratio and orientation. The orientation and its dependence on the current and rotor position are used to analyse the behaviour...... and establish the suitability of the machine for sensorless control using inductance saliency tracking methods. The same electromagnetic behaviour is used in the implementation of a dynamical simulation model of the machine useful for evaluation of sensorless control methods at the control design stage. Further...

  8. Design of permanent magnetic solenoids for REGAE

    Energy Technology Data Exchange (ETDEWEB)

    Gehrke, Tim; Zeitler, Benno; Gruener, Florian [University of Hamburg and Center for Free-Electron Laser Science, Hamburg (Germany); Floettmann, Klaus [DESY, Hamburg (Germany); Manz, Stephanie [MPSD, University of Hamburg (Germany)

    2013-07-01

    The Relativistic Electron Gun for Atomic Exploration REGAE is a small linear accelerator at DESY in Hamburg, which produces short, low emittance electron bunches. Two future experiments at REGAE, an external injection experiment for Laser Wakefield Acceleration (LWA) and a time resolving Transmission Electron Microscopy (TEM) setup, require strong focusing magnets inside the target chamber. Permanent magnetic solenoids can provide the needed focusing strength due to their enormous surface current density, while having compact dimensions at the same time. Solenoids are fundamentally non-linear focusing elements whose non-linearity is worst for short, strong magnets as required for REGAE. The induced emittance growth is investigated and minimized for different setups with axially and radially magnetized annular magnets. Since permanent magnetic solenoids cannot be switched off but are not needed in every experiment at REGAE, a mechanical lifting-system and a magnetic shielding has to ensure, that the different experiments do not disturb each other.

  9. Robotized Surface Mounting of Permanent Magnets

    Directory of Open Access Journals (Sweden)

    Erik Hultman

    2014-10-01

    Full Text Available Using permanent magnets on a rotor can both simplify the design and increase the efficiency of electric machines compared to using electromagnets. A drawback, however, is the lack of existing automated assembly methods for large machines. This paper presents and motivates a method for robotized surface mounting of permanent magnets on electric machine rotors. The translator of the Uppsala University Wave Energy Converter generator is used as an example of a rotor. The robot cell layout, equipment design and assembly process are presented and validated through computer simulations and experiments with prototype equipment. A comparison with manual assembly indicates substantial cost savings and an improved work environment. By using the flexibility of industrial robots and a scalable equipment design, it is possible for this assembly method to be adjusted for other rotor geometries and sizes. Finally, there is a discussion on the work that remains to be done on improving and integrating the robot cell into a production line.

  10. Classical toy models for the monopole shift and the quadrupole shift.

    Science.gov (United States)

    Rose, Katrin; Cottenier, Stefaan

    2012-08-28

    The penetration of s- and p(1/2)-electrons into the atomic nucleus leads to a variety of observable effects. The presence of s-electrons inside the nucleus gives rise to the isotope shift in atomic spectroscopy, and to the isomer shift in Mössbauer spectroscopy. Both well-known phenomena are manifestations of the more general monopole shift. In a recent paper (Koch et al., Phys. Rev. A, 2010, 81, 032507), we discussed the existence of the formally analogous quadrupole shift: a tensor correction to the electric quadrupole interaction due to the penetration of relativistic p(1/2)-electrons into the nucleus. The quadrupole shift is predicted to be observable by high-accuracy molecular spectroscopy on a set of 4 molecules (the quadrupole anomaly). The simple physics behind all these related phenomena is easily obscured by an elaborate mathematical formalism that is required for their derivation: a multipole expansion in combination with perturbation theory, invoking quantum physics and ideally relativity. In the present paper, we take a totally different approach. We consider three classical 'toy models' that can be solved by elementary calculus, and that nevertheless contain all essential physics of the monopole and quadrupole shifts. We hope that this intuitive (yet exact) analysis will increase the understanding about multipole shift phenomena in a broader community.

  11. Secondary cicatricial and other permanent alopecias.

    Science.gov (United States)

    Finner, Andreas M; Otberg, Nina; Shapiro, Jerry

    2008-01-01

    Various nonfollicular scalp conditions can cause secondary scarring or permanent alopecia. Possible causes are congenital defects, trauma, inflammatory conditions, infections, and neoplasms (rarely drugs). Associated signs and symptoms and other diagnostic procedures such as histopathology may aid in the diagnosis. Detection of the underlying disorder may be difficult in end-stage lesions. Treatment is specific for active conditions. Surgery and hair transplantation are options for localized scars.

  12. A Novel Permanent Magnetic Angular Acceleration Sensor

    OpenAIRE

    Hao Zhao; Hao Feng

    2015-01-01

    Angular acceleration is an important parameter for status monitoring and fault diagnosis of rotary machinery. Therefore, we developed a novel permanent magnetic angular acceleration sensor, which is without rotation angle limitations and could directly measure the instantaneous angular acceleration of the rotating system. The sensor rotor only needs to be coaxially connected with the rotating system, which enables convenient sensor installation. For the cup structure of the sensor rotor, it h...

  13. Nuclear Quadrupole Resonance Studies of Charge Distributions in Molecular Solids.

    Science.gov (United States)

    Greenbaum, Steven Garry

    A detailed description of an NMR-NQR double resonance spectrometer designed and constructed in this laboratory is given, including some instruction on its use. ('14)N NQR data obtained by pulse methods for six classes of nitrogen-containing compounds are presented and analyzed in the framework of the Townes and Dailey theory. A study of the anti-cancer drugs cyclophosphamide, isophosphamide and triphosphamide suggests the existence of a correlation between the substance's chemotherapeutic efficacy and the (pi) - (sigma)(,NP) charge density at the trigonal nitrogen. Satisfactory correlations of the NQR spectra of 22 monosubstituted anilines with both the Hammett (sigma) parameters and the in vitro biological activities of the corresponding sulfanilamides have been found, indicating that the nitrogen lone-pair orbital is more sensitive than the nitrogen-carbon sigma orbital is to substituent effects. NQR spectra of several N-acetyl amino acids and related compounds are reported. The inductive effect of the chloroacetyl group on the nitrogen is discussed. A positive correlation between the (pi) - (sigma)(,NC) electron density at the nitrogen and the Taft inductive parameter (sigma)* is observed, suggesting that the nitrogen (pi) -charge density in the N-acetyl amino acids does not vary appreciably. Both ('14)N and ('35)Cl NQR data have been obtained for a series of compounds containing nitrogen directly bonded to chlorine. The existence of a linear correlation between the ('14)N and ('35)Cl quadrupole coupling constants is interpreted in terms of a simple model dealing with charge excesses and deficiencies at the respective nuclei. A study of two complexes of 4-aminopyridine (4AP) addresses the loss of pyridine nitrogen lone-pair charge upon formation of the strong and asymmetric N-H-N bond characteristic of these complexes. Evidence of hydrogen bonding interactions involving the amino nitrogens is found to be in agreement with a published neutron diffraction study

  14. U.S. Legal Permanent Residents: Fiscal Year 2012

    Data.gov (United States)

    Department of Homeland Security — A legal permanent resident (LPR) or “green card” recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  15. U.S. Legal Permanent Residents: Fiscal Year 2009

    Data.gov (United States)

    Department of Homeland Security — A legal permanent resident (LPR) or “green card” recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  16. ARE SALAMANDERS USEFUL INDICATORS OF HYDROLOGIC PERMANENCE IN HEADWATER STREAMS?

    Science.gov (United States)

    Regulatory agencies need appropriate indicators of stream permanence to aid in jurisdictional determinations for headwater streams. We evaluated salamanders as permanence indicators because they are often abundant in fishless headwaters. Salamander and habitat data were collect...

  17. U.S. Lawful Permanent Residents: Fiscal Year 2013

    Data.gov (United States)

    Department of Homeland Security — A lawful permanent resident (LPR) or 'green card' recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  18. U.S. Legal Permanent Residents: Fiscal Year 2010

    Data.gov (United States)

    Department of Homeland Security — A legal permanent resident (LPR) or “green card” recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  19. U.S. Legal Permanent Residents: Fiscal Year 2008

    Data.gov (United States)

    Department of Homeland Security — A legal permanent resident (LPR) or “green card” recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  20. U.S. Legal Permanent Residents: Fiscal Year 2011

    Data.gov (United States)

    Department of Homeland Security — A legal permanent resident (LPR) or “green card” recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  1. U.S. Legal Permanent Residents: Fiscal Year 2007

    Data.gov (United States)

    Department of Homeland Security — A legal permanent resident (LPR) or “green card” recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  2. A Novel Single Phase Hybrid Switched Reluctance Motor Drive System

    DEFF Research Database (Denmark)

    Liang, Jianing; Xu, Guoqing; Jian, Linni

    2011-01-01

    In this paper, a novel single phase hybrid switched reluctance motor(SRM) drive system is proposed. It integrated a single phase hybrid SRM and a novel single phase boost converter. This motor can reduce the number of phase switch. And the permanent magnet which is used in the motor can improve t...... SRM reduce the negative torque before zero-crossing point of torque curve, and build desired phase current to generate more power. Some experimental results are done to verify the performance of proposed hybrid SRM drive system....

  3. 77 FR 55895 - Permanent Closure of Cincinnati Blue Ash Airport

    Science.gov (United States)

    2012-09-11

    ... Federal Aviation Administration Permanent Closure of Cincinnati Blue Ash Airport AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of permanent closure of Cincinnati Blue Ash Airport (ISZ). SUMMARY: The... Cincinnati advising that on August 29, 2012, it was permanently closing Cincinnati Blue Ash Airport...

  4. Permanent magnet design for high-speed superconducting bearings

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R. (5519 S. Bruner, Hinsdale, IL 60521); Uherka, Kenneth L. (830 Ironwood, Frankfort, IL 60423); Abdoud, Robert G. (13 Country Oaks La., Barrington Hills, IL 60010)

    1996-01-01

    A high temperature superconducting bearing including a permanent magnet rotor levitated by a high temperature superconducting structure. The rotor preferably includes one or more concentric permanent magnet rings coupled to permanent magnet ring structures having substantially triangular and quadrangular cross-sections. Both alternating and single direction polarity magnet structures can be used in the bearing.

  5. 27 CFR 22.68 - Notice of permanent discontinuance.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Notice of permanent discontinuance. 22.68 Section 22.68 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE... Permanent Discontinuance of Use of Tax-Free Alcohol § 22.68 Notice of permanent discontinuance. A...

  6. 12 CFR 615.5206 - Permanent capital ratio computation.

    Science.gov (United States)

    2010-01-01

    ... AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Capital Adequacy § 615.5206 Permanent capital ratio computation. (a) The institution's permanent capital ratio is determined on the basis of the... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Permanent capital ratio computation....

  7. 12 CFR 615.5205 - Minimum permanent capital standards.

    Science.gov (United States)

    2010-01-01

    ... AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Capital Adequacy § 615.5205 Minimum permanent capital standards. Each institution shall at all times maintain permanent capital at a level of at... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Minimum permanent capital standards....

  8. Magnet Design of the 150 mm Aperture Low-β Quadrupoles for the High Luminosity LHC

    CERN Document Server

    Ferracin, P; Anerella, M; Borgnolutti, F; Bossert, R; Cheng, D; Dietderich, D R; Felice, H; Ghosh , A; Godeke, A; Izquierdo Bermudez, S; Fessia, P; Krave, S; Juchno, M; Perez, J C; Oberli, L; Sabbi, G; Todesco, E; Yu, M

    2014-01-01

    The High Luminosity LHC (HL-LHC) project is aimed at studying and implementing the necessary changes in the LHC to increase its luminosity by a factor five. Among the magnets that will be upgraded are the 16 superconducting low-β quadrupoles placed around the two high luminosity interaction regions (ATLAS and CMS experiments). In the current baseline scenario, these quadrupole magnets will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. The resulting conductor peak field of more than 12 T will require the use of Nb3Sn superconducting coils. We present in this paper the HL-LHC low-β quadrupole design, based on the experience gathered by the US LARP program, and, in particular, we describe the support structure components to pre-load the coils, withstand the electro-magnetic forces, provide alignment and LHe containment, and integrate the cold mass in the LHC IRs.

  9. Antimagnetic rotation and sudden change of electric quadrupole transition strength in 143Eu

    Directory of Open Access Journals (Sweden)

    S. Rajbanshi

    2015-09-01

    Full Text Available Lifetimes of the states in the quadrupole structure in 143Eu have been measured using the Doppler shift attenuation method and the parity of the states in the sequence has been firmly identified from polarization measurements using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B(E2 with spin, along with increasing J(2/B(E2 values before the band crossing, conclusively establish the origin of these states as arising from antimagnetic rotation. The abrupt increase in the B(E2 values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may possibly indicate the crossing of different shears configurations resulting in the re-opening of a shears structure. The results are reproduced well by numerical calculations within the framework of a semi-classical geometric model.

  10. Antimagnetic rotation and sudden change of electric quadrupole transition strength in 143Eu

    CERN Document Server

    Rajbanshi, S; Nag, Somnath; Bisoi, Abhijit; Saha, S; Sethi, J; Trivedi, T; Bhattacharjee, T; Bhattacharyya, S; Chattopadhyay, S; Gangopadhyay, G; Mukherjee, G; Palit, R; Raut, R; Sarkar, M Saha; Singh, A K; Goswami, A

    2015-01-01

    Lifetimes of the states in the quadrupole structure in 143Eu have been measured using the Doppler shift attenuation method as well as parity of the states in the sequence has been firmly identified from polarization measurement using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B(E2) with spin, along with increasing J (2) /B(E2) values before band crossing, conclusively establish the origin of these states as arising out of antimagnetic rotation. The abrupt increase in the B(E2) values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may indicates the crossing of different shears configurations resulting in re-opening of shears structure. The results are well reproduced by numerical calculation within the framework of semi-classical geometric model.

  11. Test Results of the LARP Nb$_3$Sn Quadrupole HQ03a

    CERN Document Server

    DiMarco, J; Anerella, M; Bajas, H; Chlachidze, G; Borgnolutti, F; Bossert, R; Cheng, D W; Dietderich, D; Felice, H; Pan, H; Ferracin, P; Ghosh, A; Godeke, A; Hafalia, A R; Marchevsky, M; Orris, D; Ravaioli, E; Sabbi, G; Salmi, T; Schmalzle, J; Stoynev, S; Strauss, T; Sylvester, C; Tartaglia, M; Todesco, E; Wanderer, P; Wang, X R; Yu, M

    2016-01-01

    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. This paper reports a summary of the HQ03a test results, including training, mechanical performance, field quality and quench studies.

  12. Use of RF quadrupole structures to enhance stability in accelerator rings

    CERN Document Server

    AUTHOR|(CDS)2091303; Grudiev, Alexej; Li, Kevin Shing Bruce; Papke, Kai

    2016-01-01

    The beams required for the high luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN call for efficient mechanisms to suppress transverse collective instabilities. In addition to octupole magnets installed for the purpose of Landau damping, we propose to use radio frequency (rf) quadrupole structures to considerably enhance the aforementioned stabilising effect. By means of the PyHEADTAIL macroparticle tracking code, the stabilising mechanism introduced by an rf quadrupole is studied and discussed. As a specific example, the performance of an rf quadrupole system in presence of magnetic octupoles is demonstrated for HL-LHC. Furthermore, potential performance limitations such as the excitation of synchro-betatron resonances are pointed out. Finally, efforts towards possible measurements with the CERN Super Proton Synchrotron (SPS) are discussed aiming at studying the underlying stabilising mechanisms experimentally.

  13. Stabilization and positioning of CLIC quadrupole magnets with sub-nanometre resolution

    CERN Document Server

    Janssens, S; Collette, C; Esposito, M; Fernandez Carmona, P; Guinchard, M; Hauviller, C; Kuzmin, A; Leuxe, R; Moron Ballester, R

    2011-01-01

    To reach the required luminosity at the CLIC interaction point, about 2000 quadrupoles along each linear collider are needed to obtain a vertical beam size of 1 nm at the interaction point. Active mechanical stabilization is required to limit the vibrations of the magnetic axis to the nanometre level in a frequency range from 1 to 100 Hz. The approach of a stiff actuator support was chosen to isolate from ground motion and technical vibrations acting directly on the quadrupoles. The actuators can also reposition the quadrupoles between beam pulses with nanometre resolution. A first conceptual design of the active stabilization and nano positioning based on the stiff support and seismometers was validated in models and experimentally demonstrated on test benches. Lessons learnt from the test benches and information from integrated luminosity simulations using measured stabilization transfer functions lead to improvements of the actuating support, the sensors used and the system controller. The controller elect...

  14. Direct trace analysis of metals and alloys in a quadrupole ion-trap mass spectrometer

    CERN Document Server

    Song, K S; Yang, M; Cha, H K; Lee, J M; Lee, G H

    1999-01-01

    An ion-trap mass spectrometer adopting a quadrupole ion-trap and laser ablation/ionization method was constructed. The developed system was tested for composition analysis of some metals (Cu, stainless), and alloys (hastalloy C, mumetal) by mass spectrometry. Samples were analyzed by using laser ablation from a sample probe tip followed by a mass analysis with the quadrupole ion-trap. The quadrupole ion-trap was modified to enable laser ablation by a XeCl excimer laser pulse that passed radially through the ring electrode. A mass scan of the produced ions was performed in the mass selective instability mode wherein trapped ions were successively detected by increasing the rf voltage through the ring electrode. Factors affecting the mass resolution, such as pressure of buffer gas and ablation laser power, are discussed.

  15. Origin-independent calculation of quadrupole intensities in X-ray spectroscopy

    CERN Document Server

    Bernadotte, Stephan; Jacob, Christoph R

    2012-01-01

    For electronic excitations in the ultraviolet and visible range of the electromagnetic spectrum, the intensities are usually calculated within the dipole approximation, which assumes that the oscillating electric field is constant over the whole molecule. For the short wavelengths used in X-ray spectroscopy, this dipole approximation breaks down and it becomes necessary to include higher-order contributions. In quantum-chemical approaches to X-ray spectroscopy, these so-called quadrupole intensities have so far been calculated by including contributions depending on the square of the electric-quadrupole and magnetic-dipole transition moments. However, the resulting quadrupole intensities depend on the choice of the origin of the coordinate system. Here, we show that for obtaining an origin-independent theory, one has to include all contributions that are of the same order in the wave vector consistently. This leads to two additional contributions depending on products of the electric-dipole and electric-octup...

  16. Superconducting Quadrupole Prototype for the ISR high luminosity (low beta) insertion

    CERN Multimedia

    1977-01-01

    In colliders, smaller beam cross-section means higher luminosity. Beam-size being proportional to the square-root of the "beta function" value, a small beta means small beam size, hence high luminosity. In 1973 a study was launched on low-beta insertions using superconducting quadrupole magnets, which focus beams to very small sizes at the beam crossing points . In 1976 the first prototype of a superconducting quadrupole was tested. Here we see Theodor Tortschanoff with the prototype of 1.25 m magnetic length. Manufacture of 8 quadrupoles (4 of L=1.15 m, 4 of L=0.65 m) began at Alsthom in 1978. They were installed at intersection I8 of the ISR, enhancing luminosity there by a factor 7 until final low-beta operation in December 1983. For details see "Yellow Report" CERN 76-16. See also pictures 7702307, 7702308, 7702182,7510214X,7510217X.

  17. Manifestation of the strong quadrupole light-molecule interaction in the SEHR spectra of symmetrical molecules

    CERN Document Server

    Polubotko, A M

    2009-01-01

    The paper demonstrates possibility of giant enhancement of Surface Enhanced Hyper Raman Scattering on the base of qualitative consideration of electromagnetic field near some models of rough metal surfaces and of some features of the dipole and quadrupole light-molecule interaction, such as it was made in the dipole-quadrupole SERS theory. Consideration of symmetrical molecules permits to obtain selection rules for their SEHR spectra and establish such regularity as appearance of the bands, caused by the totally symmetric vibrations, transforming after the unitary irreducible representation in molecules with C2h,D and higher symmetry groups, which are forbidden in usual HRS spectra. Analysis of literature data on trans-1,2-bis (4-pyridyle) ethylene and pyridine molecules demonstrates that their SEHR spectra can be explained by the SEHRS dipole-quadrupole theory, while analysis of the SEHR spectrum of pyrazine reveals appearance of the strong forbidden bands, caused by vibrations transforming after the unitary...

  18. Production of 87Rb Bose-Einstein condensates in a hybrid trap

    Institute of Scientific and Technical Information of China (English)

    Duan Ya-Fan; Jiang Bo-Nan; Sun Jian-Fang; Liu Kang-Kang; Xu Zhen; Wang Yu-Zhu

    2013-01-01

    We report a rapid evaporative cooling method using a hybrid trap which is composed of a quadrupole magnetic trap and a one-beam optical dipole trap.It contains two kinds of evaporative coolings to reach the quantum degeneracy:initial radio-frequency (RF) enforced evaporative cooling in the quadrupole magnetic trap and further runaway evaporative cooling in the optical dipole trap.The hybrid trap does not require a very high power laser such as that in the traditional pure optical trap,but still has a deep trap depth and a large trap volume,and has better optical access than the normal magnetic trap like the quadrupole-Ioffe-configuration (QUIC) cloverleaf trap.A high trap frequency can be easily realized in the hybrid trap to enhance the elastic collision rate and shorten the evaporative cooling time.In our experiment,pure Bose-Einstein condensates (BECs) with about 1 × 105 atoms can be realized in 6 s evaporative cooling in the optical dipole trap.

  19. Simple expressions of the nuclear relaxation rate enhancement due to quadrupole nuclei in slowly tumbling molecules

    Energy Technology Data Exchange (ETDEWEB)

    Fries, Pascal H., E-mail: pascal-h.fries@cea.fr [Université Grenoble Alpes, INAC-SCIB, RICC, F-38000 Grenoble (France); CEA, INAC-SCIB, RICC, F-38000 Grenoble (France); Belorizky, Elie [Université Grenoble Alpes, LIPHY, F-38000 Grenoble (France); CEA, Leti-Clinatec, F-38000 Grenoble (France)

    2015-07-28

    For slowly tumbling entities or quasi-rigid lattices, we derive very simple analytical expressions of the quadrupole relaxation enhancement (QRE) of the longitudinal relaxation rate R{sub 1} of nuclear spins I due to their intramolecular magnetic dipolar coupling with quadrupole nuclei of arbitrary spins S ≥ 1. These expressions are obtained by using the adiabatic approximation for evaluating the time evolution operator of the quantum states of the quadrupole nuclei S. They are valid when the gyromagnetic ratio of the spin S is much smaller than that of the spin I. The theory predicts quadrupole resonant peaks in the dispersion curve of R{sub 1} vs magnetic field. The number, positions, relative intensities, Lorentzian shapes, and widths of these peaks are explained in terms of the following properties: the magnitude of the quadrupole Hamiltonian and the asymmetry parameter of the electric field gradient (EFG) acting on the spin S, the S-I inter-spin orientation with respect to the EFG principal axes, the rotational correlation time of the entity carrying the S–I pair, and/or the proper relaxation time of the spin S. The theory is first applied to protein amide protons undergoing dipolar coupling with fast-relaxing quadrupole {sup 14}N nuclei and mediating the QRE to the observed bulk water protons. The theoretical QRE agrees well with its experimental counterpart for various systems such as bovine pancreatic trypsin inhibitor and cartilages. The anomalous behaviour of the relaxation rate of protons in synthetic aluminium silicate imogolite nano-tubes due to the QRE of {sup 27}Al (S = 5/2) nuclei is also explained.

  20. Hybrid superconductor magnet bearings

    Science.gov (United States)

    Chu, Wei-Kan

    1995-01-01

    Hybrid superconductor magnet bearings (HSMB's) utilize high temperature superconductors (HTS's) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS's, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, we present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  1. Tests of a 70 mm aperture quadrupole for the LHC low-$\\beta$ insertions

    CERN Document Server

    Lamm, M J; Ostojic, R; Rival, F; Rodríguez-Mateos, F; Siemko, A; Taylor, T M; Walckiers, L; Milward, S R; Treadgold, J R

    1999-01-01

    Three 70 mm aperture 1-meter superconducting quadrupole magnets for the LHC low- beta insertions have been designed and built in collaboration between CERN and Oxford Instruments. These magnets feature a four layer coil wound fromtwo 8.2 mm wide graded NbTi cables. In this paper, the authors present the results from the tests at 4.4 K and 1.9 K of the third quadrupole (Q3), with an emphasis on studies concerning quench protection. After a summary of Q3 training in three thermal cycles, quench velocities, peak temperatures in the two superconducting cables and the performance of the layer strip heaters are reported. (6 refs).

  2. Quadrupole splitting and isomer shifts in Te oxides investigated using nuclear forward scattering

    Science.gov (United States)

    Klobes, Benedikt; Barrier, Nicolas; Vertruyen, Benedicte; Martin, Christine; Hermann, Raphaël P.

    2014-04-01

    Nuclear forward scattering by 125Te is a viable alternative to conventional 125Te Mössbauer spectroscopy avoiding all source related issues. Using reference compounds with known hyperfine parameters and Te oxides exhibiting stereochemically active lone pairs, we show that nuclear forward scattering by 125Te can be reliably used to extract quadrupole splitting energy and relative isomer shift. The rough correlation between Te-Ocoordination and quadrupole splitting energy as put forward by Takeda and Greenwood (J. Chem. Soc. Dalton, 2207, 1975), is corroborated by the presented results.

  3. Optimization of transfer of laser-cooled atom cloud to a quadrupole magnetic

    Indian Academy of Sciences (India)

    S P Ram; S K Tiwari; S R Mishra; H S Rawat

    2014-02-01

    We present here our experimental results on transfer of laser-cooled atom cloud to a quadrupole magnetic trap. We show that by choosing appropriately the ratio of potential energy in magnetic trap to kinetic energy of cloud in molasses, we can obtain the maximum phase-space density in the magnetic trap. These results guide us to choose the value of current to be switched in the quadrupole coils used for magnetic trapping for a given temperature of the cloud after molasses. This study is also useful to set the initial phase-space density of the cloud before evaporative cooling.

  4. Low-lying bands with different quadrupole deformation in 155Dy

    Directory of Open Access Journals (Sweden)

    Petkov P.

    2014-03-01

    Full Text Available To investigate the interplay between collective and single particle degrees of freedom in odd nuclei, Recoil distance Doppler-shift and Doppler-shift attenuation lifetime measurements were carried out for levels in 155Dy in coincidence detection of gamma-rays. 26 lifetimes were determined using the Differential decay curve method. Particle plus triaxial rotor model (PTRM calculations were performed to compare the experimental level scheme and transition strengths with theoretical ones in order to get information on the quadrupole deformation (є,γ of the bands. As a result, different quadrupole deformations for the one-quasineutron bands at low and medium spins are deduced.

  5. Odd-spin yrast states as multiple quadrupole-phonon excitations

    CERN Document Server

    Pietralla, N; Otsuka, T; Casten, R F

    1995-01-01

    The wavefunctions of the lowest odd spin positive parity yrast states in the IBA are shown to be nearly pure multiple quadrupole-phonon excitations even outside the three dynamical symmetries. The empirical data for collective nuclei with 30 < Z < 80 confirm these predictions. The quadrupole-phonon purity of the 2^+_1 state can be measured from E2-branching ratios of the 3^+_1 state. These data show a high correlation to the 2^+_1 Q-phonon purity deduced from the E2-decay of 2^+ states.

  6. Quenching behaviour of quadrupole model magnets for the LHC inner triplets at Fermilab

    CERN Document Server

    Andreev, N; Bauer, P; Bossert, R; Brandt, J; Chichili, D R; Carson, J; Di Marco, J; Fehér, S; Glass, H; Kerby, J S; Lamm, M J; Makarov, A A; Nobrega, A; Novitski, I; Ogitsu, T; Orris, D; Ozelis, J P; Rabehl, Roger Jon; Robotham, W; Sabbi, G L; Schlabach, P; Sylvester, C D; Strait, J B; Tartaglia, M; Tompkins, J C; Yadav, S; Zlobin, A V; Caspi, S; McInturff, A D; Scanlan, R M; Ghosh, A

    2000-01-01

    The US-LHC Accelerator Project is responsible for the design and production of inner triplet high gradient quadrupoles for installation in the LHC Interaction Region. The quadrupoles are required to deliver a nominal field gradient of 215 T/m in a 70 mm bore, and operate in superfluid helium. As part of the magnet development program, a series of 2 m model magnets have been built and tested at Fermilab, with each magnet being tested over several thermal cycles. This paper summarizes the quench performance and analysis of the model magnets tested, including quench training, and the ramp rate and temperature of the magnet quench current. (7 refs).

  7. Electric quadrupole moments of {beta}-emitter {sup 21}F and {sup 23}Mg

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Takashi; Matsuta, Kensaku; Fukuda, Mitsunori [Osaka Univ., Toyonaka (Japan). Faculty of Science] [and others

    1997-03-01

    For the systematic study of nuclear electromagnetic moments, electric quadrupole moments Q of {beta}-emitting nuclei {sup 21}F and {sup 23}Mg have been measured for the first time through combined technique of the polarized nuclear beams and {beta}-NMR technique. From the quadrupole coupling constants of {sup 21}F and {sup 23}Mg in MgF{sub 2} single crystal, the ratios of the Q`s with the known Q were determined as |Q({sup 21}F)|/|Q({sup 19}F{sup *})|=1.001{+-}0.034 and |Q({sup 23}Mg)|/|Q({sup 25}Mg)|=0.571{+-}0.017. (author)

  8. Design and fabrication of the first quadrupole magnet for the ILSF storage ring

    Directory of Open Access Journals (Sweden)

    F Saeidi

    2015-09-01

    Full Text Available The Iranian Light Source Facility (ILSF is a new 3 GeV third generation synchrotron light source which is consisted of several pre-accelerators and a storage ring with the beam current of 400 mA. Based on the main lattice candidate, the storage ring includes of 100 dipoles, 320 quadrupoles and 320 sextupole magnets. To develop fabrication procedures and techniques and to compare the measurement results with the design data, a series of lattice magnets have been fabricated inside Iran with internal industries. In this article the first prototype quadrupole magnet fabrication process has been described

  9. Numerical validation of the thermal quadrupoles method for a flow in a microchannel

    Directory of Open Access Journals (Sweden)

    Sabrine Mejri, Olivier Fudym, Jalila Sghaier, Ahmed Bellagi

    2016-01-01

    Full Text Available The main objective of this work is to investigate and validate the thermal quadrupole method, used in this paper as a semi-analytical method to solve the equations of a falling film in a heated microchannel studied experimentally. In the experimental section, we created a temperature gradient within the liquid, while monitoring the temperature using an infrared camera. Then, a numerical model is established and solved by the thermal quadrupole method. Finally, we conclude with a comparison between the experiments and the numerical study.

  10. An effect of nuclear electric quadrupole moments in thermonuclear fusion plasmas

    Science.gov (United States)

    De, B. R.; Srnka, L. J.

    1978-01-01

    Consideration of the nuclear electric quadrupole terms in the expression for the fusion Coulomb barrier suggests that this electrostatic barrier may be substantially modified from that calculated under the usual plasma assumption that the nuclei are electric monopoles. This effect is a result of the nonspherical potential shape and the spatial quantization of the nuclear spins of the fully stripped ions in the presence of a magnetic field. For monopole-quadrupole fuel cycles like p-B-11, the fusion cross-section may be substantially increased at low energies if the protons are injected at a small angle relative to the confining magnetic field.

  11. Pulsed spectrometer for nuclear quadrupole resonance for remote detection of nitrogen in explosives

    Science.gov (United States)

    Anferov, V. P.; Mozjoukhine, G. V.; Fisher, R.

    2000-04-01

    We describe a pulsed spectrometer for detection of nuclear quadrupole resonance on the nuclei of nitrogen N-14 with fast Fourier transform. The use of a multipulse sequence, four channel system for data registration and processing permits detection of the nuclear quadrupole resonance (NQR) signal in the presence of strong interference and the piezo effect. Using this spectrometer we registered the NQR signal from an explosive sample of 150 g (92% RDX) at a distance of 22 cm, and the time of detection was 81 s.

  12. Hybrid microelectronic technology

    Science.gov (United States)

    Moran, P.

    Various areas of hybrid microelectronic technology are discussed. The topics addressed include: basic thick film processing, thick film pastes and substrates, add-on components and attachment methods, thin film processing, and design of thick film hybrid circuits. Also considered are: packaging hybrid circuits, automating the production of hybrid circuits, application of hybrid techniques, customer's view of hybrid technology, and quality control and assurance in hybrid circuit production.

  13. Permanent cardiac pacing in pediatric patients.

    Science.gov (United States)

    Lotfy, Wael; Hegazy, Ranya; AbdElAziz, Osama; Sobhy, Rodina; Hasanein, Hossam; Shaltout, Fawzan

    2013-02-01

    Pediatric pacemaker (PM) implants comprise less than 1 % of all PM implants. This study aimed to investigate permanent cardiac pacing among the pediatric population, identifying different indications and complications of pediatric cardiac pacing, especially focusing on the effect of the pacing sites, the PM lead type, and the indications for pacing. The current work is a cross-sectional study of 103 procedures for permanent PM insertion in pediatric patients between January 2001 and December 2010. The patients were followed up 1, 3, and 6 months after implantation, then every 6 months or as needed. Evaluation included routine clinical examination, electrocardiography, chest X-ray, echocardiography, and a full analysis of the pacing system measurements. The ages of the patients ranged from 0.09 to 12 years (median, 2.3 years). The most common indication for pacing was postoperative complete heart bock, noted in 54 patients (52.4 %). Transvenous endocardial PM insertion was performed in 92 procedures (89.3 %), whereas transthoracic epicardial insertion was performed in 11 procedures (10.7 %). The most common site of pacing was the right ventricular apex (n = 64, 62 %), followed by the right ventricular outflow tract (n = 25, 24.3 %). Transthoracic epicardial PM insertion was associated with a significantly higher percentage and greater severity of complications. In this study, 65 % of the patients with left ventricle (LV) dilation before pacing showed a significant improvement in LV dimensions and function after pacing. This was noted only in those with endocardially inserted PM leads in both the congenital and the postoperative groups regardless of the pacing site. Endocardial PM insertion in children is a safe procedure with fewer complications and a lower ventricular threshold than the epicardial route. Permanent single-chamber right ventricle pacing is safe and can lead to significant improvement in LV function and dimensions. However, long-term follow

  14. Deciduous canine and permanent lateral incisor differential root resorption.

    Science.gov (United States)

    Davies, K R; Schneider, G B; Southard, T E; Hillis, S L; Wertz, P W; Finkelstein, M; Hogan, M M

    2001-10-01

    When a permanent maxillary canine erupts apical to the permanent lateral incisor and the deciduous canine, resorption typically takes place only on the deciduous canine root. An understanding of this differential resorption could provide insight into the reasons for excessive iatrogenic root resorption during orthodontic tooth movement. The purpose of the present study was to examine the response of roots of permanent lateral incisors and deciduous canines to simulated resorption, and to acid and enzyme attack, reflecting the physiologic environment of an erupting permanent canine. Groups of maxillary permanent lateral incisor and deciduous canine roots were exposed to 5 combinations of Ten Cate demineralizing solution, Ten Cate demineralizing solution with EDTA, and a Type I collagenase solution. Sections of the roots were examined under a polarized light microscope. Analysis of variation of the resulting root lesions demonstrated that the lesion depths for deciduous canines were greater than those for permanent lateral incisors when averaged across 4 of the conditions (F(1,24) = 7.49, P =.0115). On average, deciduous canine roots demonstrated lesions 10% deeper than did permanent lateral incisor roots. We concluded that when deciduous canine and permanent lateral incisor roots are subjected to acid and enzyme attack, reflecting the physiologic environment of an erupting permanent canine, significantly deeper demineralized lesions are seen in the deciduous roots compared with the permanent roots. This finding may partially explain the differential root resorption during permanent tooth eruption.

  15. Permanent Magnet Eddy Current Loss Analysis of a Novel Motor Integrated Permanent Magnet Gear

    DEFF Research Database (Denmark)

    Zhang, Yuqiu; Lu, Kaiyuan; Ye, Yunyue

    2012-01-01

    In this paper, a new motor integrated permanent magnet gear (MIPMG) is discussed. The focus is on eddy current loss analysis associated to permanent magnets (PMs). A convenient model of MIPMG is provided based on 2-D field-motion coupled time-stepping finite element method for transient eddy...... current analysis. The model takes the eddy current effect of PMs into account in determination of the magnetic field in the air-gap and in the magnet regions. The eddy current losses generated in the magnets are properly interpreted. Design improvements for reducing the eddy current losses are suggested...

  16. Permanent magnetic toroidal drive with half stator

    Directory of Open Access Journals (Sweden)

    Lizhong Xu

    2017-01-01

    Full Text Available A permanent magnetic toroidal drive with a half stator is proposed that avoids noise and mechanical vibrations. The effects of the system parameters on the output torque of the drive were investigated. A model machine was designed and produced. The output torque and speed fluctuation of the drive system were measured, and the calculated and measured output torque were compared. The tests demonstrated that the drive system could operate continuously without noise, and the system achieved a given speed ratio. The drive system had high load-carrying ability and a maximum output torque of 0.15 N m when certain parameter values were used.

  17. Permanent Commission for Health and Safety

    CERN Document Server

    Association du personnel

    2007-01-01

    The mandate of the Staff Association's permanent commission for Health and Safety is to examine all aspects of health and safety related to the working environment at CERN. In no way does it wish to be a substitute for the official bodies that are responsible for these matters. The Commission's aim is to formulate remarks on and make proposals about these questions to the relevant bodies and the CERN Management. Its main focus is the safety of the CERN staff but it is also concerned with the safety of the installations and of the CERN environment. The Commission reports to the Staff Council and the Executive Committee of the Staff Association.

  18. Perlite for permanent confinement of cesium

    Science.gov (United States)

    Balencie, J.; Burger, D.; Rehspringer, J.-L.; Estournès, C.; Vilminot, S.; Richard-Plouet, M.; Boos, A.

    2006-06-01

    We present the potential use of expanded perlite, a metastable amorphous hydrated aluminium silicate, as a permanent medium for the long-term confinement of cesium. The method requires simply a loading by mixing an aqueous cesium nitrate solution and expanded perlite at 300 K followed by densification by sintering. The formation of pollucite, CsAlSi2O6, a naturally occurring mineral phase, upon careful heat treatment is demonstrated by X-ray diffraction. Leaching tests on the resulting glass-ceramics reveal a very low Cs departure of 0.5 mg m-2 d-1.

  19. Strong permanent magnet-assisted electromagnetic undulator

    Science.gov (United States)

    Halbach, Klaus

    1988-01-01

    This invention discloses an improved undulator comprising a plurality of electromagnet poles located along opposite sides of a particle beam axis with alternate north and south poles on each side of the beam to cause the beam to wiggle or undulate as it travels generally along the beam axis and permanent magnets spaced adjacent the electromagnetic poles on each side of the axis of said particle beam in an orientation sufficient to reduce the saturation of the electromagnet poles whereby the field strength of the electromagnet poles can be increased beyond the normal saturation levels of the electromagnetic poles.

  20. Hyperfine-induced quadrupole moments of alkali-metal atom ground states and their implications for atomic clocks

    CERN Document Server

    Derevianko, Andrei

    2016-01-01

    Spherically-symmetric ground states of alkali-metal atoms do not posses electric quadrupole moments. However, the hyperfine interaction between nuclear moments and atomic electrons distorts the spherical symmetry of electronic clouds and leads to non-vanishing atomic quadrupole moments. We evaluate these hyperfine-induced quadrupole moments using techniques of relativistic many-body theory and compile results for Li, Na, K, Rb, and Cs atoms. For heavy atoms we find that the hyperfine-induced quadrupole moments are strongly (two orders of magnitude) enhanced by correlation effects. We further apply the results of the calculation to microwave atomic clocks where the coupling of atomic quadrupole moments to gradients of electric fields leads to clock frequency uncertainties. We show that for $^{133}$Cs atomic clocks, the spatial gradients of electric fields must be smaller than $30 \\, \\mathrm{V}/\\mathrm{cm}^2$ to guarantee fractional inaccuracies below $10^{-16}$.