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1

Evidence for Magnetic-Field-Induced Quadrupolar Ordering in the Heavy-Fermion Superconductor PrOs4Sb12  

Microsoft Academic Search

Neutron diffraction experiments on the heavy-fermion superconductor PrOs4Sb12 revealed that a small antiferromagnetic moment, parallel to [010] (y-direction), is induced in the field-induced phase (H \\\\parallel z). The analysis, based on the Gamma1 singlet ground state crystal field model, shows that antiferro-order of Oyz-type quadrupole moments of Pr ions is formed in the field-induced phase. This strongly suggests that the

Masahumi Kohgi; Kazuaki Iwasa; Motoki Nakajima; Naoto Metoki; Shingo Araki; Nick Bernhoeft; Jean-Michel Mignot; Arsen Gukasov; Hideyuki Sato; Yuji Aoki; Hitoshi Sugawara

2003-01-01

2

Magnetic-field-induced quantum critical point and competing order parameters in URu2Si2.  

PubMed

A comprehensive transport study, as a function of temperature and continuous magnetic fields of up to 45 T, reveals that URu2Si2 possesses all the essential hallmarks of quantum criticality at fields around 37+/-1 T. The formation of multiple phases at low temperatures at and around the quantum critical point suggests the existence of competing order parameters. PMID:14754130

Kim, K H; Harrison, N; Jaime, M; Boebinger, G S; Mydosh, J A

2003-12-19

3

Magnetic field induced third order susceptibility of third order harmonic generation in a ZnMgSe strained quantum well  

SciTech Connect

Third order susceptibility of third order harmonic generation is investigated in a Zn{sub 0.1}Mg{sub 0.9}Se/Zn{sub 0.8}Mg{sub 0.2}Se/Zn{sub 0.1}Mg{sub 0.9}Se quantum well in the presence of magnetic field strength. The confinement potential is considered as the addition of energy offsets of the conduction band (or valence band) and the strain-induced potential in our calculations. The material dependent effective mass is followed throughout the computation because it has a high influence on the electron energy levels in low dimensional semiconductor systems.

Mark, J. Abraham Hudson, E-mail: a.john.peter@gmail.com; Peter, A. John, E-mail: a.john.peter@gmail.com [Dept. of Physics, SSM Institute of Engineering and Technology, Dindigul-624002 (India)

2014-04-24

4

A first-order magnetic phase transition near 15 K with novel magnetic-field-induced effects in Er5Si3.  

PubMed

We present magnetic characterization of a binary rare-earth intermetallic compound Er(5)Si(3), crystallizing in Mn(5)Si(3)-type hexagonal structure, through magnetization, heat capacity, electrical resistivity and magnetoresistance measurements. Our investigations confirm that the compound exhibits two magnetic transitions with decreasing temperature, the first one at 35 K and the second one at 15 K. The present results reveal that the second magnetic transition is a disorder-broadened first-order transition, as shown by thermal hysteresis in the measured data. Another important finding is that, below 15 K, there is a magnetic-field-induced transition with a hysteretic effect with the electrical resistance getting unusually enhanced at this transition and the magnetoresistance is found to exhibit intriguing magnetic-field dependence, indicating novel magnetic phase coexistence phenomenon. It thus appears that this compound is characterized by interesting magnetic anomalies in the temperature-magnetic-field phase diagram. PMID:22089704

Mohapatra, Niharika; Mukherjee, K; Iyer, Kartik K; Sampathkumaran, E V

2011-12-14

5

Quadrupolar Ordering in Solid Hydrogen and Deuterium.  

NASA Astrophysics Data System (ADS)

A study is presented of NMR absorption spectra and relaxation in solid hydrogen and solid deuterium at temperatures accessible via dilution refrigeration, with emphasis on the local ordering phenomena which occur for temperatures T(, )<(, )300mK and concentrations X of J = 1 molecules which apparently preclude Pa(,3) ordering (0.2 < X < 0.5). An important aspect of these experiments was the use of large thermal contact areas in conjunction with nuclear magnetic thermometry. This permitted an accurate assessment of the thermal gradients produced by spin-species conversion within the samples. In H(,2), the line broadening associated with lowering temperature for X < 0.5 was found to be very gradual, showing no evidence for a phase transition or for a well -defined spin-glass-like transition. Absorption line shapes were identical on warming and cooling, aside from small changes attributable to ortho-para conversion, provided that confusion with the irreversible crystal-structure change which occurs near X = 0.5 was avoided. The line -shape data for X = 0.43 were fitted to a model incorporating a broad distribution of energy splittings for the J = 1 molecules. The relaxation time for holes burned in the line for ortho concentrations X < 0.5 was also measured. In D(,2), the spin-lattice relaxation time t(,1) for J = 0 molecules was measured at a Larmor frequency of 46MHz for temperatures 40mK < T < 700mK and para-concentrations 0.24 < X < 0.31. The discontinuity in the derivative of t(,1) with respect to temperature for T (DBLTURN) 170mK which had been reported in the literature was not confirmed. Rather, our data showed an extremely broad minimum in t(,1)(T) for T (DBLTURN) 300mK. Taken together with higher-temperature measurements that have been reported by others, our data suggest an gradual slowing-down of orientational fluctuations as the temperature is lowered. A model of cross-relaxation was developed which allows the relaxation time of J = 1 molecules in D(,2) to be inferred from the observed relaxation time for J = 0 molecules. The inferred J = 1 relaxation time was fitted to a model of thermally-activated orientational fluctuations. This procedure suggested that the thermal barriers to molecular reorientation are randomly distributed between 0.2K and 1.0K.

Candela, Donald

6

Magnetic field induced dynamical chaos  

SciTech Connect

In this article, we have studied the dynamics of a particle having charge in the presence of a magnetic field. The motion of the particle is confined in the x–y plane under a two dimensional nonlinear potential. We have shown that constant magnetic field induced dynamical chaos is possible even for a force which is derived from a simple potential. For a given strength of the magnetic field, initial position, and velocity of the particle, the dynamics may be regular, but it may become chaotic when the field is time dependent. Chaotic dynamics is very often if the field is time dependent. Origin of chaos has been explored using the Hamiltonian function of the dynamics in terms of action and angle variables. Applicability of the present study has been discussed with a few examples.

Ray, Somrita; Baura, Alendu; Bag, Bidhan Chandra, E-mail: bidhanchandra.bag@visva-bharati.ac.in [Department of Chemistry, Visva-Bharati, Santiniketan 731 235 (India)

2013-12-15

7

Magnetic-field-induced charge order in the filled skutterudite SmRu4P12: Evidence from resonant and nonresonant x-ray diffraction  

NASA Astrophysics Data System (ADS)

The antiferromagnetic ordered phase in SmRu4P12 below the metal-insulator transition at TMI=16.5 K with an unresolved transition at T*˜14 K has been studied by resonant and nonresonant x-ray diffraction in magnetic fields. In the intermediate phase, a nonresonant Thomson scattering with q =(1,0,0) is induced by applying a magnetic field, which is presumably caused by atomic displacements reflecting the charge order in the p band, as predicted theoretically [R. Shiina, J. Phys. Soc. Jpn. 82, 083713 (2013), 10.7566/JPSJ.82.083713]. Simultaneously, the antiferromagnetic moment of Sm is enhanced along the field direction, which is considered to reflect the staggered ordering of the ?7-?8 crystal-field states (scalar or hexadecapole order). The present results show that the orbital-dependent p-f hybridization in association with the nesting instability in the p band gives rise to the unconventional charge order similarly with PrRu4P12 and PrFe4P12.

Matsumura, Takeshi; Michimura, Shinji; Inami, Toshiya; Hayashi, Yuya; Fushiya, Kengo; Matsuda, Tatsuma D.; Higashinaka, Ryuji; Aoki, Yuji; Sugawara, Hitoshi

2014-04-01

8

Magnetic field induced optical vortex beam rotation  

E-print Network

Light with orbital angular momentum (OAM) has drawn a great deal of attention for its important applications in the fields of precise optical measurements and high capacity optical communications. Here we adopt a method to study the rotation of a light beam, which is based on magnetic field induced circular birefringence in warm 87Rb atomic vapor. The dependence of the rotation angle to the intensity of the magnetic field makes it appropriate for weak magnetic field measurement. We derive a detail theoretical description that is in well agreement with the experimental observations. The experiment shows here provides a new method for precise measurement of magnetic field intensity and expands the application of OAM-carrying light.

Shi, Shuai; Zhou, Zhi-Yuan; Li, Yan; Zhang, Wei; Shi, Bao-Sen

2015-01-01

9

Magnetic-field-induced shape recovery by reverse phase transformation.  

PubMed

Large magnetic-field-induced strains have been observed in Heusler alloys with a body-centred cubic ordered structure and have been explained by the rearrangement of martensite structural variants due to an external magnetic field. These materials have attracted considerable attention as potential magnetic actuator materials. Here we report the magnetic-field-induced shape recovery of a compressively deformed NiCoMnIn alloy. Stresses of over 100 MPa are generated in the material on the application of a magnetic field of 70 kOe; such stress levels are approximately 50 times larger than that generated in a previous ferromagnetic shape-memory alloy. We observed 3 per cent deformation and almost full recovery of the original shape of the alloy. We attribute this deformation behaviour to a reverse transformation from the antiferromagnetic (or paramagnetic) martensitic to the ferromagnetic parent phase at 298 K in the Ni45Co5Mn36.7In13.3 single crystal. PMID:16495995

Kainuma, R; Imano, Y; Ito, W; Sutou, Y; Morito, H; Okamoto, S; Kitakami, O; Oikawa, K; Fujita, A; Kanomata, T; Ishida, K

2006-02-23

10

DC magnetic field-induced second harmonic generation of laser beam  

Microsoft Academic Search

Second harmonic generation (SHG) in the presence of a dc magnetic field H0 is described by a new axial tensor of third-order non-linear susceptibility Kijkl (-2omega, omega, omega, 0). Relations between its non-zero elements are derived by group theory for all crystallographical classes. In classes 422(D6), 622(D6), 432 (O), Y and K a magnetic field induces SHG, which at H0

S. Kielich; R. Zawodny

1971-01-01

11

Thermo- and magnetic-field-induced dynamics of ferroelectric interphase boundaries  

NASA Astrophysics Data System (ADS)

Thermo- and magnetic-field-induced dynamics of first-order ferroelectric and antiferroelectric phase transitions are considered, taking into account the inertia effect. The width and velocity of interphase boundaries are calculated as functions of temperature and magnetic field strength. The results obtained here are essentially different from those of the Ginzburg-Landau theory and of the case of the small kinetic energy term, and they may also be used for the description of the kinetics of ferroelectric phase transitions in high-temperature superconductive perovskites.

Gordon, A.; Vagner, I. D.; Wyder, P.

1993-09-01

12

Magnetic-Field Induced Diffraction Patterns from Ferrofluids  

NASA Astrophysics Data System (ADS)

Ferrofluids are stable colloidal suspensions of superparamagnetic nanoparticles in a carrier liquid. We report studies of magneto-optic properties of two ferrofluid systems consisting of tetramethyl-ammonium-hydroxide (TMAH)-coated and of dextran-coated Fe3O4 nanoparticles of nominal sizes of 6 nm and 12 nm respectively suspended in water. Both samples showed superparamagnetic behavior. The static and time-dependent DC-magnetic-field-induced light scattering patterns produced by two orthogonal He-Ne laser beams passing through the ferrofluid samples revealed significant different optical signatures for the two surfactants. Notably, in contrast to the linear diffraction pattern produced by TMAH-coated nanoparticles, a circular diffraction pattern is reported -- for the first time -- in the dextran-coated ferrofluid.

Rablau, Corneliu; Vaishnava, Prem; Lawes, Gavin; Naik, Ratna

2011-04-01

13

Giant magnetic-field-induced strains in Heusler alloy NiMnGa with modified composition  

E-print Network

Giant magnetic-field-induced strains in Heusler alloy NiMnGa with modified composition G. H. Wu September 1999 A giant magnetic-field-induced strain MFIS of 3100 ppm has been obtained in Heusler alloy Ni Institute of Physics. S0003-6951 99 02545-0 Heusler alloy Ni2MnGa has been systematically investi- gated

Zheng, Yufeng

14

Optical gyrotropy in quadrupolar Kondo systems  

NASA Astrophysics Data System (ADS)

Recent experiments point to a variety of intermetallic systems which exhibit exotic quadrupolar orders driven by the Kondo coupling between conduction electrons and localized quadrupolar degrees of freedom. Using a Luttinger k .p Hamiltonian for the conduction electrons, we study the impact of such quadrupolar order on their energies and wave functions. We discover that such quadrupolar orders can induce a nontrivial Berry curvature for the conduction electron bands, leading to a nonvanishing optical gyrotropic effect. We estimate the magnitude of the gyrotropic response in a candidate quadrupolar material, PrPb3, and discuss the resulting Faraday rotation in thin films.

Lee, SungBin; Paramekanti, Arun; Kim, Yong Baek

2015-01-01

15

12% magnetic field-induced strain in Ni-Mn-Ga-based non-modulated martensite  

NASA Astrophysics Data System (ADS)

Magnetic field-induced strain (MFIS) of 12% is reported in ferromagnetic Ni46Mn24Ga22Co4Cu4 martensite exhibiting non-modulated (NM) tetragonal crystal structure with lattice parameter ratio c /a>1. The strain was measured at ambient temperature in a magnetic field of the order of 1 T. The twinning stress ?TW and the magnetic stress ?MAG were also measured and the condition for a giant MFIS observation ?TW

Sozinov, A.; Lanska, N.; Soroka, A.; Zou, W.

2013-01-01

16

Magnetic-field-induced ferroelectric polarization reversal in the multiferroic Ge(1-x)Mn(x)Te semiconductor.  

PubMed

Ge(1-x)Mn(x)Te is shown to be a multiferroic semiconductor, exhibiting both ferromagnetic and ferroelectric properties. By ferromagnetic resonance we demonstrate that both types of order are coupled to each other. As a result, magnetic-field-induced ferroelectric polarization reversal is achieved. Switching of the spontaneous electric dipole moment is monitored by changes in the magnetocrystalline anisotropy. This also reveals that the ferroelectric polarization reversal is accompanied by a reorientation of the hard and easy magnetization axes. By tuning the GeMnTe composition, the interplay between ferromagnetism and ferroelectricity can be controlled. PMID:24580486

Przybyli?ska, H; Springholz, G; Lechner, R T; Hassan, M; Wegscheider, M; Jantsch, W; Bauer, G

2014-01-31

17

Magnetic-Field-Induced Ferroelectric Polarization Reversal in the Multiferroic Ge1-xMnxTe Semiconductor  

NASA Astrophysics Data System (ADS)

Ge1-xMnxTe is shown to be a multiferroic semiconductor, exhibiting both ferromagnetic and ferroelectric properties. By ferromagnetic resonance we demonstrate that both types of order are coupled to each other. As a result, magnetic-field-induced ferroelectric polarization reversal is achieved. Switching of the spontaneous electric dipole moment is monitored by changes in the magnetocrystalline anisotropy. This also reveals that the ferroelectric polarization reversal is accompanied by a reorientation of the hard and easy magnetization axes. By tuning the GeMnTe composition, the interplay between ferromagnetism and ferroelectricity can be controlled.

Przybyli?ska, H.; Springholz, G.; Lechner, R. T.; Hassan, M.; Wegscheider, M.; Jantsch, W.; Bauer, G.

2014-01-01

18

Interplay of quadrupolar order, Ce 4f spin dynamics and RKKY induced conduction electron spin polarization in CeAg  

NASA Astrophysics Data System (ADS)

We report on measurements of the Knight shift K and spin-lattice relaxation rate lgr of positive muons (mgr+) implanted in cubic CeAg, a compound which is known to possess ferromagnetic (T_{\\mathrm {c}} \\simeq 5.5 K) and ferroquadrupolar (TQ = 15-16 K) order. The zero field (ZF) lgr implies randomly and isotropically fluctuating Ce 4f moments above TQ which show a trend to a, perhaps critical, slowing down on approaching TQ. Below TQ the fluctuations are restricted to the now tetragonally distorted axis of CeAg. In a longitudinal field the generally isotropic fluctuations show a tendency towards freezing near Tc, not TQ. The Knight shift results reveal an anisotropic contact hyperfine coupling parameter Ac, which displays abrupt changes at Tc. ZF measurements below Tc reveal the presence of discrete spontaneous internal fields. The results on lgr and Ac are interpreted as arising from quadrupolar effects, concerning in particular the induced spin polarization of the conduction electron system.

Schenck, A.; Gygax, F. N.; Andreica, D.; Onuki, Y.

2003-12-01

19

Temperature and magnetic field induced multiple magnetic transitions in DyAg(2).  

PubMed

The magnetic properties of the rare-earth intermetallic compound DyAg(2) are studied in detail with the help of magnetization and heat capacity measurements. It is shown that the multiple magnetic phase transitions can be induced in DyAg(2) both by temperature and magnetic field. The detailed magnetic phase diagram of DyAg(2) is determined experimentally. It was already known that DyAg(2) undergoes an incommensurate to commensurate antiferromagnetic phase transition close to 10 K. The present experimental results highlight the first order nature of this phase transition, and show that this transition can be induced by magnetic field as well. It is further shown that another isothermal magnetic field induced transition or metamagnetic transition exhibited by DyAg(2) at still lower temperatures is also of first order nature. The multiple magnetic phase transitions in DyAg(2) give rise to large peaks in the temperature dependence of the heat capacity below 17 K, which indicates its potential as a magnetic regenerator material for cryocooler related applications. In addition it is found that because of the presence of the temperature and field induced magnetic phase transitions, and because of short range magnetic correlations deep inside the paramagnetic regime, DyAg(2) exhibits a fairly large magnetocaloric effect over a wide temperature window, e.g., between 10 and 60 K. PMID:21406918

Arora, Parul; Chattopadhyay, M K; Sharath Chandra, L S; Sharma, V K; Roy, S B

2011-02-01

20

Singularities in the lineshape of a second-order perturbed quadrupolar nucleus and their use in data fitting.  

PubMed

Even for large quadrupolar interactions, the powder spectrum of the central transition for a half-integral spin is relatively narrow, because it is unperturbed to first order. However, the second-order perturbation is still orientation dependent, so it generates a characteristic lineshape. This lineshape has both finite step discontinuities and singularities where the spectrum is infinite, in theory. The relative positions of these features are well-known and they play an important role in fitting experimental data. However, there has been relatively little discussion of how high the steps are, so we present explicit formulae for these heights. This gives a full characterization of the features in this lineshape which can lead to an analysis of the spectrum without the usual laborious powder average. The transition frequency, as a function of the orientation angles, shows critical points: maxima, minima and saddle points. The maxima and minima correspond to the step discontinuities and the saddle points generate the singularities. Near a maximum, the contours are ellipses, whose dimensions are determined by the second derivatives of the frequency with respect to the polar and azimuthal angles. The density of points is smooth as the contour levels move up and down, but then drops to zero when a maximum is passed, giving a step. The height of the step is determined by the Hessian matrix-the matrix of all partial second derivatives. The points near the poles and the saddle points require a more detailed analysis, but this can still be done analytically. The resulting formulae are then compared to numerical simulations of the lineshape. We expand this calculation to include a relatively simple case where there is chemical shielding anisotropy and use this to fit experimental (139)La spectra of La2O3. PMID:24992819

Field, Timothy R; Bain, Alex D

2014-01-01

21

C N.M.R. and N N.Q.R. in ferroelectric liquid crystals Polar versus quadrupolar ordering  

Microsoft Academic Search

C nuclear magnetic resonance and N nuclear quadrupole resonance spectra of ferroelectric smectic C*liquid crystals and their non-chiral analogues allow for a microscopic determination of the polar and quadrupolar (or bipolar) biasing of rotation around the long molecular axis as well as for a determination of the anisotropy in the fluctuations of this axis. The results show that the microscopic

R. Blinc; J. Dolinšek; M. Luzar; J. Seliger

1988-01-01

22

Observation of magnetic-field-induced superconductivity in a heavy-fermion antiferromagnet: CePb3  

Microsoft Academic Search

We report here an entirely new phenomenon, namely magnetic-field-induced superconductivity in CePb3, a system which at zero field is a heavy-fermion antiferromagnet. This phenomenon is novel in several respects. It is the first reported heavy-fermion magnetic-field-induced superconductor. It is also the first reported magnetic-field-induced superconductor that is also an antiferromagnet. Moreover, it has the simplest crystal structure, Cu3Au, of any

C. L. Lin; J. Teter; J. E. Crow; T. Mihalisin; J. Brooks; A. I. Abou-Aly; G. R. Stewart

1985-01-01

23

Effects of hole doping by neutron irradiation of magnetic field induced electronic phase transitions in graphite  

SciTech Connect

We have investigated effects of hole doping by fast-neutron irradiation on the magnetic-field induced phase transitions in graphite using specimens irradiated with fast neutrons. Resistance measurements have been done in magnetic fields of up to above 50 T and at temperatures down to about 1.5 K. The neutron irradiation creates lattice defects acting as acceptors, affecting the imbalance of the electron and hole densities and the Fermi level. We have found that the reentrant field from the field induced state back to the normal state shifts towards a lower field with hole doping, suggestive of the participation of electron subbands in the magnetic-field induced state.

Singleton, John [Los Alamos National Laboratory; Yaguchi, Hiroshi [TOKYO UNIV

2008-01-01

24

Magnetic field induced effects in optical second harmonic generation from iron-garnet films  

NASA Astrophysics Data System (ADS)

The magnetic field induced effects in the second harmonic generation (SHG) from epitaxially grown iron-garnet films have been studied. The magnetic field induced variations in the azimuthal angular dependences and the polarization diagrams of the SHG intensity are shown to be due to the linear Faraday effect. Enhancements in the SHG intensity were detected for (Bi,Gd,Fu) 3(Fe,Ga) 5O 12 iron-garnet films grown on (Gd,Ca) 3(Mg,Zr,Ga) 5O 12 single-crystal substrates with various orientations. This dependence of the SHG intensity on the magnetic field may be caused by magnetostriction effects.

Aktsipetrov, O. A.; Aleshkevich, V. A.; Melnikov, A. V.; Misuryaev, T. V.; Murzina, T. V.; Randoshkin, V. V.

1997-01-01

25

Magnetic field induced phase transformation in polycrystalline NiCoMnAl thin films  

NASA Astrophysics Data System (ADS)

NiCoMnAl thin films were deposited onto unheated substrates using dc magnetron co-sputtering. The microstructure of as-deposited films consisted of nanocrystals in an amorphous matrix and did not exhibit a martensitic phase transformation. After heat treatment, films crystallized into a B2 austenite phase, which exhibited a magnetic field induced martensitic phase transformation. The level of the change in the martensitic transformation temperatures in the magnetic field was determined to be ˜2.1 K/T. The films exhibited non-reversible magnetic field induced martensite to austenite transformation due to the large thermal hysteresis.

Rios, S.; Bufford, D.; Karaman, I.; Wang, H.; Zhang, X.

2013-09-01

26

Enhancement of magnetic-field-induced strain in Ni–Fe–Ga–Co Heusler alloy  

Microsoft Academic Search

The mobility of the twin boundary and the magnetocrystalline anisotropy constant K at 300K in the martensite phase of Ni51Fe18Ga27Co3 with a 7-layered (14M) structure are estimated. The martensite phase exhibits a large magnetic-field-induced strain of about 0.7% at 300K.

H. Morito; K. Oikawa; A. Fujita; K. Fukamichi; R. Kainuma; K. Ishida

2005-01-01

27

Magnetic field-induced excitation and optical detection of mechanical modes of microspheres  

E-print Network

Magnetic field-induced excitation and optical detection of mechanical modes of microspheres T We propose a method to excite and detect the mechanical modes of dielectric microspheres In this paper, we propose a method to excite and detect the mechanical modes of dielectric microspheres using

�tügen, Volkan

28

Magnetic-field-induced crystallographic texture enhancement in cold-deformed FePt nanostructured magnets  

E-print Network

Magnetic-field-induced crystallographic texture enhancement in cold-deformed FePt nanostructured magnets B. Z. Cuia and K. Han National High Magnetic Field Laboratory, Florida State University Grenoble, France H. J. Schneider-Muntau National High Magnetic Field Laboratory, Florida State University

Garmestani, Hamid

29

Artificial magnetic field induced by an evanescent wave.  

PubMed

Cold atomic gases are perfect laboratories for realization of quantum simulators. In order to simulate solid state systems in the presence of magnetic fields special effort has to be made because atoms are charge neutral. There are different methods for realization of artificial magnetic fields, that is the creation of specific conditions so that the motion of neutral particles mimics the dynamics of charged particles in an effective magnetic field. Here, we consider adiabatic motion of atoms in the presence of an evanescent wave. Theoretical description of the adiabatic motion involves artificial vector and scalar potentials related to the Berry phases. Due to the large gradient of the evanescent field amplitude, the potentials can be strong enough to induce measurable effects in cold atomic gases. We show that the resulting artificial magnetic field is able to induce vortices in a Bose-Einstein condensate trapped close to a surface of a prism where the evanescent wave is created. We also analyze motion of an atomic cloud released from a magneto-optical trap that falls down on the surface of the prism. The artificial magnetic field is able to reflect falling atoms that can be observed experimentally. PMID:25567430

Mochol, Ma?gorzata; Sacha, Krzysztof

2015-01-01

30

Artificial magnetic field induced by an evanescent wave  

NASA Astrophysics Data System (ADS)

Cold atomic gases are perfect laboratories for realization of quantum simulators. In order to simulate solid state systems in the presence of magnetic fields special effort has to be made because atoms are charge neutral. There are different methods for realization of artificial magnetic fields, that is the creation of specific conditions so that the motion of neutral particles mimics the dynamics of charged particles in an effective magnetic field. Here, we consider adiabatic motion of atoms in the presence of an evanescent wave. Theoretical description of the adiabatic motion involves artificial vector and scalar potentials related to the Berry phases. Due to the large gradient of the evanescent field amplitude, the potentials can be strong enough to induce measurable effects in cold atomic gases. We show that the resulting artificial magnetic field is able to induce vortices in a Bose-Einstein condensate trapped close to a surface of a prism where the evanescent wave is created. We also analyze motion of an atomic cloud released from a magneto-optical trap that falls down on the surface of the prism. The artificial magnetic field is able to reflect falling atoms that can be observed experimentally.

Mochol, Ma?gorzata; Sacha, Krzysztof

2015-01-01

31

Artificial magnetic field induced by an evanescent wave  

PubMed Central

Cold atomic gases are perfect laboratories for realization of quantum simulators. In order to simulate solid state systems in the presence of magnetic fields special effort has to be made because atoms are charge neutral. There are different methods for realization of artificial magnetic fields, that is the creation of specific conditions so that the motion of neutral particles mimics the dynamics of charged particles in an effective magnetic field. Here, we consider adiabatic motion of atoms in the presence of an evanescent wave. Theoretical description of the adiabatic motion involves artificial vector and scalar potentials related to the Berry phases. Due to the large gradient of the evanescent field amplitude, the potentials can be strong enough to induce measurable effects in cold atomic gases. We show that the resulting artificial magnetic field is able to induce vortices in a Bose-Einstein condensate trapped close to a surface of a prism where the evanescent wave is created. We also analyze motion of an atomic cloud released from a magneto-optical trap that falls down on the surface of the prism. The artificial magnetic field is able to reflect falling atoms that can be observed experimentally. PMID:25567430

Mochol, Ma?gorzata; Sacha, Krzysztof

2015-01-01

32

Magnetic-field-induced quadrupole coupling in the nuclear magnetic resonance of noble-gas atoms and molecules  

SciTech Connect

An analytic response theory formulation for the leading-order magnetic field-induced and field-dependent quadrupole splitting in nuclear magnetic resonance spectra is presented and demonstrated with first-principles calculations for {sup 21}Ne, {sup 36}Ar, and {sup 83}Kr in noble gas atoms. The case of molecules was studied for {sup 33}S in the sulphur hexafluoride molecule, as well as for {sup 47/49}Ti, {sup 91}Zr, and {sup 177,179}Hf in group(IV) tetrahalides. According to our calculations, the hitherto experimentally unknown field-induced quadrupole splitting in molecules rises to 10{sup 2} Hz for {sup 177,179}Hf nuclei in HfF{sub 4} and 10{sup 1} Hz for {sup 47/49}Ti in TiCl{sub 4}, and is hence of observable magnitude.

Manninen, Pekka [Laboratory of Physical Chemistry, Department of Chemistry, P.O. Box 55 (A.I. Virtasen aukio 1), FIN-00014 University of Helsinki (Finland); NMR Research Group, Department of Physical Sciences, P.O. Box 3000, FIN-90014 University of Oulu (Finland); Vaara, Juha [Laboratory of Physical Chemistry, Department of Chemistry, P.O. Box 55 (A.I. Virtasen aukio 1), FIN-00014 University of Helsinki (Finland); Pyykkoe, Pekka [Laboratory for Instruction in Swedish, Department of Chemistry, P.O. Box 55 (A.I. Virtasen aukio 1), FIN-00014 University of Helsinki (Finland)

2004-10-01

33

Restatement of order parameters in biomembranes: calculation of C-C bond order parameters from C-D quadrupolar splittings.  

PubMed Central

An expression for the C-C bond order parameter, SCC, of membrane hydrocarbon chains has been derived from the observed C-D bond order parameters. It allows calculation of the probability of each of the C-C bond rotamers and, consequently, the number of gauche defects per chain as well as their projected average length onto the bilayer normal, thus affording the calculation of accurate hydrophobic bilayer thicknesses. The effect of temperature has been studied on dilauroyl-, dimyristoyl-, and dipalmitoylphosphatidylcholine (DLPC, DMPC, DPPC) membranes, as has the effect of cholesterol on DMPC. The salient results are as follows: 1) an odd-even effect is observed for the SCC versus carbon position, k, whose amplitude increases with temperature; 2) calculation of SCC, from nonequivalent deuterons on the sn-2 chain of lipids, SCC2, leads to negative values, indicating the tendency for the C1-C2 bond to be oriented parallel to the bilayer surface; this bond becomes more parallel to the surface as the temperature increases or when cholesterol is added; 3) calculation on the sn-2 chain length can be performed from C1 to Cn, where n is the number of carbon atoms in the chain, and leads to 10.4, 12.2, and 13.8 A for DLPC, DMPC, and DPPC close to the transition temperature, TC, of each of the systems and to 9.4, 10.9, and 12.6 for T-TC = 30-40 degrees C, respectively; 4) separation of intra- and intermolecular motions allows quantitation of the number of gauche defects per chain, which is equal to 1.9, 2.7, and 3.5 for DLPC, DMPC, and DPPC near TC and to 2.7, 3.5, and 4.4 at T-TC = 30-40 degrees C, respectively. Finally, the validity of our model is discussed and compared with previously published models. PMID:7612816

Douliez, J P; Léonard, A; Dufourc, E J

1995-01-01

34

Nuclear magnetic double resonance based on strong rf magnetic-field-induced coupling between spin systems  

Microsoft Academic Search

The origin of the rf magnetic-field-induced coupling between spin systems is discussed. A new nuclear-double-resonance technique employing this coupling is proposed, which has particular value in measuring pure nuclear-quadrupole-resonance spectra of integer-spin nuclei by nuclear double resonance. The sensitivity of the new technique is discussed for the case of 1H-14N double resonance in zero static magnetic field, as well as

J. Seliger; R. Blinc; M. Mali; R. Osredkar; A. Prelesnik

1975-01-01

35

Magnetic-field-induced phases in anisotropic triangular antiferromagnets: Application to CuCrO2  

NASA Astrophysics Data System (ADS)

We introduce a minimal spin model for describing the magnetic properties of CuCrO2. Our Monte Carlo simulations of this model reveal a rich magnetic-field-induced phase diagram, which explains the measured field dependence of the electric polarization. The sequence of phase transitions between different multiferroic states arises from a subtle interplay between spatial and spin anisotropy, magnetic frustration, and thermal fluctuations. Our calculations are compared to new measurements up to 92 T.

Lin, Shi-Zeng; Barros, Kipton; Mun, Eundeok; Kim, Jae-Wook; Frontzek, Matthias; Barilo, S.; Shiryaev, S. V.; Zapf, Vivien S.; Batista, Cristian D.

2014-06-01

36

Magnetic-field-induced nonparabolicity of exciton dispersion in semiconductors with a nondegenerate valence band  

SciTech Connect

The nonparabolicity of exciton dispersion due to the mixing of the ground and excited states of an exciton in an external magnetic field perpendicular to the direction of its motion is considered. A model describing this effect is proposed and the nonparabolicity for an exciton in a CdTe crystal is calculated. The magnetic-field induced exciton nonparabolicity is compared with the effect caused by the nonparabolicity of the electron energy dispersion in the conduction band.

Loginov, D. K., E-mail: loginov999@gmail.com; Chegodaev, A. D. [St. Petersburg State University (Russian Federation)

2011-09-15

37

Magnetic field-induced martensitic transformation and large magnetoresistance in NiCoMnSb alloys  

E-print Network

of Physics. DOI: 10.1063/1.2748095 Off-stoichiometric Heusler alloys Ni50Mn50-yXy X =In,Sn and the relatedMagnetic field-induced martensitic transformation and large magnetoresistance in NiCoMnSb alloys S in Ni50-xCoxMn39Sb11 alloys. The partial substitution of Co for Ni has turned the antiferromagnetically

Zexian, Cao

38

Magnetic field induced quantum phase transitions in the two-impurity Anderson model  

SciTech Connect

In the two-impurity Anderson model, the inter-impurity spin exchange interaction favors a spin singlet state between two impurities leading to the localization of quasiparticles. We show that a local uniform magnetic field can delocalize the quasiparticies to restore the Kondo resonance. This transition is found to be continuous, accompanied by not only the divergence of the staggered (anti ferromagnetic) susceptibility, but also the divergence of the uniform spin susceptibility. This implies that the magnetic field induced quantum phase transitions in Kondo systems are in favor of the local critical type.

Zhu, Lujun [Los Alamos National Laboratory; Zhu, Jian - Xin [Los Alamos National Laboratory

2010-11-17

39

Magnetic field induced tailoring of mechanical behavior of fluid filled micro porous carbon nanotube foam  

NASA Astrophysics Data System (ADS)

Compressive loading of the carbon nanotube (CNT) has attracted much attention due to its entangled cellular like structure (CNT foam). This report investigates the mechanical behavior of magnetorheological fluid impregnated micro porous CNT foam that has not been realized before at this scale. Compressive behavior of CNT foam is found to greatly depend on the variation in both fluid viscosity as well as magnetic field intensity. Moreover, maximum achieved stress and energy absorption in CNT foam followed a power law behavior with the magnetic field intensity. Magnetic field induced movement of both CNT and iron oxide particles along the field direction is shown to dominate compressive behavior of CNT foam over highly attractive van der Waals forces between individual CNT. Therefore, this study demonstrates a method for tailoring the mechanical behavior of the fluid impregnated CNT foam.

Reddy, Siva Kumar; Mukherjee, Anwesha; Misra, Abha

2014-06-01

40

Magnetic-field-induced ferroelectric polarization reversal in magnetoelectric composites revealed by piezoresponse force microscopy.  

PubMed

Controlling electric polarization (or magnetization) in multiferroic materials with external magnetic fields (or electric fields) is very important for fundamental physics and spintronic devices. Although there has been some progress on magnetic-field-induced polarization reversal in single-phase multiferroics, such behavior has so far never been realized in composites. Here we show that it is possible to reverse ferroelectric polarization using magnetic fields in a bilayer Terfenol-D/PMN-33%PT composite. We realized this by ferroelectric domain imaging using piezoresponse force microscopy (PFM) under applied magnetic field loading. The internal electric field caused by the magnetoelectric (ME) effect in the PMN-PT crystal is considered as the driving force for the 180° polarization switching, and its existence is verified by switching spectroscopy PFM testing under a series of external magnetic fields. A quantitative method is further suggested to estimate the local ME coefficient based on the switching spectroscopy PFM testing results. PMID:24953042

Miao, Hongchen; Zhou, Xilong; Dong, Shuxiang; Luo, Haosu; Li, Faxin

2014-08-01

41

Magnetic-field-induced transformation in FeMnGa alloys  

SciTech Connect

A kind of ferromagnetic shape memory alloy with off-stoichiometric composition of Heusler alloy Fe{sub 2}MnGa has been synthesized. By optimizing composition, the martensitic transformation has been modified to occur at about 163 K accompanying spontaneous magnetization, which enables a magnetic field-induced structural transition from a paramagnetic parent phase to a ferromagnetic martensite with high magnetization of 93.8 emu/g. The material performs a quite large lattice distortion through the transformation, (c-a)/c=33.5%, causing a shape memory strain upto 3.6%. Such large lattice distortions strongly influence the electron structures, and thus some special physical behavior related to the transport and conductive properties is investigated.

Zhu, W.; Liu, E. K.; Feng, L.; Tang, X. D.; Chen, J. L.; Wu, G. H. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Liu, H. Y.; Meng, F. B.; Luo, H. Z. [School of Material Science and Engineering, Hebei University of Technology, Tianjin 300130 (China)

2009-11-30

42

Magnetic-field-induced strains and magnetic properties of Heusler alloy Ni52Mn23Ga25  

E-print Network

Magnetic-field-induced strains and magnetic properties of Heusler alloy Ni52Mn23Ga25 C. H. Yu, W. H has been obtained from the Heusler alloy Ni52Mn23Ga25 at 300 K. The temperature for structure 79708-8 I. INTRODUCTION Heusler alloy Ni2MnGa is a ferromagnetic material ex- hibiting a martensitic

Zheng, Yufeng

43

Phenomenology of giant magnetic-field-induced strain in ferromagnetic shape-memory materials (invited)  

SciTech Connect

Ferromagnetic shape-memory alloys have recently emerged as a new class of active materials showing very large magnetic-field-induced extensional strains. Recently, a single crystal of a tetragonally distorted Heusler alloy in the NiMnGa system has shown a 5% shear strain at room temperature in a field of 4 kOe. The magnetic and crystallographic aspects of the twin-boundary motion responsible for this effect are described. Ferromagnetic shape-memory alloys strain by virtue of the motion of the boundaries separating adjacent twin variants. The twin-boundary motion is driven by the Zeeman energy difference between the adjacent twins due to their nearly orthogonal magnetic easy axes and large magnetocrystalline anisotropy. The twin boundary constitutes a nearly 90 degree sign domain wall. Essentially, twin-boundary motion shorts out the more difficult magnetization rotation process. The field and stress dependence of the strain are reasonably well accounted for by minimization of a simple free energy expression including Zeeman energy, magnetic anisotropy energy, internal elastic energy, and external stress. Models indicate the limits to the magnitude of the field-induced strain and point to the material parameters that make the effect possible. The field-induced strain in ferromagnetic shape-memory alloys is contrasted with the more familiar phenomenon of magnetostriction. (c) 2000 American Institute of Physics.

O'Handley, R. C. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Murray, S. J. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Marioni, M. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Nembach, H. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Allen, S. M. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2000-05-01

44

Nanosize effects on the magnetic field induced transitions in La0.67-xEuxCa0.33MnO3 perovskite manganite  

NASA Astrophysics Data System (ADS)

The nanosize effects on magnetic field induced transitions in La0.67-xEuxCa0.33MnO3 (x=0.25 and 0.27) system are presented in this paper. The reduction in the particle size of the system shows drastic effects on the electrical transport properties leading to robustness of the charge ordering phenomenon. The metal-insulator transition found in bulk materials at low magnetic fields disappeared in nanoparticles of the same material and a high field induced metal-insulator transition emerged at lower temperatures. These results manifest a strong correlation between the chemical pressures induced by doping of various ions at A-site and nanosize related phenomenon.

Raju, N.; Roja Sree, D.; Reddy, S. Shravan Kumar; Reddy, Ch. Gopal; Reddy, P. Yadagiri; Reddy, K. Rama; Reddy, V. Raghavendra; Reddy Turpu, Goverdhan

2014-11-01

45

Magnetic-field-induced DNA strand breaks in brain cells of the rat.  

PubMed Central

In previous research, we found that rats acutely (2 hr) exposed to a 60-Hz sinusoidal magnetic field at intensities of 0.1-0.5 millitesla (mT) showed increases in DNA single- and double-strand breaks in their brain cells. Further research showed that these effects could be blocked by pretreating the rats with the free radical scavengers melatonin and N-tert-butyl-alpha-phenylnitrone, suggesting the involvement of free radicals. In the present study, effects of magnetic field exposure on brain cell DNA in the rat were further investigated. Exposure to a 60-Hz magnetic field at 0.01 mT for 24 hr caused a significant increase in DNA single- and double-strand breaks. Prolonging the exposure to 48 hr caused a larger increase. This indicates that the effect is cumulative. In addition, treatment with Trolox (a vitamin E analog) or 7-nitroindazole (a nitric oxide synthase inhibitor) blocked magnetic-field-induced DNA strand breaks. These data further support a role of free radicals on the effects of magnetic fields. Treatment with the iron chelator deferiprone also blocked the effects of magnetic fields on brain cell DNA, suggesting the involvement of iron. Acute magnetic field exposure increased apoptosis and necrosis of brain cells in the rat. We hypothesize that exposure to a 60-Hz magnetic field initiates an iron-mediated process (e.g., the Fenton reaction) that increases free radical formation in brain cells, leading to DNA strand breaks and cell death. This hypothesis could have an important implication for the possible health effects associated with exposure to extremely low-frequency magnetic fields in the public and occupational environments. PMID:15121512

Lai, Henry; Singh, Narendra P

2004-01-01

46

Magnetic field-induced phase transformation in NiMnCoIn magnetic shape memory alloys - a new actuation mechanism with large work output.  

SciTech Connect

Magnetic shape memory alloys (MSMAs) have recently been developed into a new class of functional materials that are capable of magnetic-field-induced actuation, mechanical sensing, magnetic refrigeration, and energy harvesting. In the present work, the magnetic field-induced martensitic phase transformation (FIPT) in Ni{sub 45}Mn{sub 36.5}Co{sub 5}In{sub 13.5} MSMA single crystals is characterized as a new actuation mechanism with potential to result in ultra-high actuation work outputs. The effects of the applied magnetic field on the transformation temperatures, magnetization, and superelastic response are investigated. The magnetic work output of NiMnCoIn alloys is determined to be more than 1 MJ m{sup -3} per Tesla, which is one order of magnitude higher than that of the most well-known MSMAs, i.e., NiMnGa alloys. In addition, the work output of NiMnCoIn alloys is orientation independent, potentially surpassing the need for single crystals, and not limited by a saturation magnetic field, as opposed to NiMnGa MSMAs. Experimental and theoretical transformation strains and magnetostress levels are determined as a function of crystal orientation. It is found that [111]-oriented crystals can demonstrate a magnetostress level of 140 MPa T{sup -1} with 1.2% axial strain under compression. These field-induced stress and strain levels are significantly higher than those from existing piezoelectric and magnetostrictive actuators. A thermodynamical framework is introduced to comprehend the magnetic energy contributions during FIPT. The present work reveals that the magnetic FIPT mechanism is promising for magnetic actuation applications and provides new opportunities for applications requiring high actuation work-outputs with relatively large actuation frequencies. One potential issue is the requirement for relatively high critical magnetic fields and field intervals (1.5-3 T) for the onset of FIPT and for reversible FIPT, respectively.

Karaca, H. E.; Karaman, I.; Basaran, B.; Ren, Y.; Chumlyakov, Y. I.; Maier, H. J.; X-Ray Science Division; Texsas A& M Univ.; Univ. of Kentucky; Siberian Physical-Technical Inst.; Univ. of Paderborn

2009-04-09

47

Second-order quadrupolar effects on NMR spectra of spin- {1}/{2} nuclei in solids, transmitted by dipolar coupling. compounds containing 55Mn (S = {5}/{2}), 59Co (S = {7}/{2}), and, 93Nb (S = {9}/{2})  

NASA Astrophysics Data System (ADS)

The theory for second-order quadrupolar effects on the centerband for magic-anglespinning solid-state NMR spectra of spin-2 nuclei dipolar-coupled to a quadrupolar nucleus is summarized. Experimental examples are presented for 31P bonded to 55Mn, 59Co, and 93b in seven compounds. The information content is discussed, especially for the case where the three tensors involved are axially symmetric and are coaxial. Spinning-sideband patterns are used to expand the data obtained. Isotropic coupling constants and isotropic chemical shifts are presented, together with additional tensor information where the analysis permits.

Gobetto, Roberto; Harris, Robin K.; Apperley, David C.

48

The derivation of effective spin Hamiltonians and the origin of the magnetic field induced transition in orthormbic La sub 2 CuO sub 4  

SciTech Connect

La{sub 2}CuO{sub 4} undergoes a magnetic field induced transition in a field of {approx}5.7 Tesla at low temperatures. The origin of this transition is the Dzyaloshinskii-Moriya interaction which is present in effective spin Hamiltonians for systems of sufficiently low symmetry, and, which leads to weak ferromagnetism in the CuO planes in La{sub 2}CuO{sub 4}. It is shown here how this interaction depends on symmetry and how its form changes with structural phase transitions which occur in compounds closely related to La{sub 2}CuO{sub 4}. These different forms of the interaction lead to different properties in magnetic fields. I also discuss how the approach presented here of determining an effective spin Hamiltonian from symmetry is related to the determination of terms in the free expansion close to a second order phase transition. It is pointed out that the present approach may be extended to itinerant systems and 1 take UPt{sub 3} as an example. 28 refs., 4 figs.

Coffey, D.

1991-01-01

49

Microwave complex permeability of Fe3O4 nanoflake composites with and without magnetic field-induced rotational orientation  

NASA Astrophysics Data System (ADS)

Magnetite (Fe3O4) nanoflakes with widths of 100-200 nm and thicknesses of 10-80 nm were prepared by a hydrothermal synthesis method. Fe3O4 nanoflake composites with and without magnetic field-induced rotational orientation of flake planes of Fe3O4 nanoflakes in paraffin binder were fabricated using 35 wt. % Fe3O4 nanoflakes. The rotationally oriented composite showed higher permeability and resonance frequency than the nonoriented one, and its value of (?0-1)fr reached 214.8 GHz and exceeded the Snoek's limit. Considering a uniform and a random distribution of flake planes of Fe3O4 nanoflakes in the oriented and nonoriented composites, respectively, the complex permeability of both composites was calculated using the Landau-Lifshitz-Gilbert equation and the Bruggeman's effective medium theory in the 2-18 GHz microwave frequency range.

Liu, Xianguo; Wing Or, Siu; Ming Leung, Chung; Ho, S. L.

2013-05-01

50

Magnetic-field-induced superconductivity and superfluidity of W and Z bosons: in tandem transport and kaleidoscopic vortex states  

E-print Network

We show that in a background of a sufficiently strong magnetic field the electroweak sector of the quantum vacuum exhibits superconducting and, simultaneously, superfluid properties due to magnetic-field-induced condensation of, respectively, W and Z bosons. The phase transition to the "tandem" superconductor--superfluid phase - which is weakly sensitive to the Higgs sector of the standard model - occurs at the critical magnetic field of 10^{20} Tesla. The superconductor-superfluid phase has anisotropic transport properties as both charged and neutral superflows may propagate only along the magnetic field axis. The ground state possesses an unusual "kaleidoscopic" structure made of a hexagonal lattice of superfluid vortices superimposed on a triangular lattice of superconductor vortices. A weak electric field will induce both superconducting and, unexpectedly, superfluid flows.

Chernodub, M N; Verschelde, Henri

2013-01-01

51

Magnetic-field-induced Heisenberg to XY crossover in a quasi-2D quantum antiferromagnet  

NASA Astrophysics Data System (ADS)

The magnetic-field-dependent ordering temperature of the quasi-2D quantum Heisenberg antiferromagnet (QHAF) Cu(pz)2(ClO4)2 was determined by calorimetric measurement in applied dc fields up to 33 tesla. The magnetic phase diagram shows a round maximum at 5.95 K and 17.5 T (at ? 1/3 of its saturation field), a 40 percent enhancement of the ordering temperature above the zero field value of 4.25 K. The enhancement and reentrance are consistent with predictions of a field-induced Heisenberg to XY crossover behavior for an ideal 2D QHAF system.

Fortune, N. A.; Hannahs, S. T.; Landee, C. P.; Turnbull, M. M.; Xiao, F.

2014-12-01

52

Physica B 403 (2008) 909910 Neutron diffraction study of magnetic field induced behavior  

E-print Network

QX, UK e Argonne National Laboratory, Argonne, IL 60439, USA f NIST Center for Neutron Research crystal samples. The (0 0 1) position shows a dramatic increase in intensity in field which appears of long-range magnetic order [5]. Inelastic neutron scattering studies show two crystal field excitations

Lawrence, Jon

53

Entropy change linked to the magnetic field induced Morin transition in Hematite nanoparticles  

NASA Astrophysics Data System (ADS)

The most stable form of iron oxide is Hematite (?-Fe2O3), which has interesting electronic, catalytic, and magnetic properties showing size dependent characteristics. At room temperature, Hematite is weakly ferromagnetic with a rhombohedral corundum structure. Upon cooling, the structure undergoes a first order spin reorientation, in which the net magnetic moment is lost. This transition is called the Morin transition. In this work, the first order Morin transition has been analyzed as a function of the temperature and applied magnetic field in Hematite nanoparticles. The magnetization was measured in the temperature range of the transformation at different applied magnetic fields to evaluate the entropy change linked to the Morin transition. The magnetic field promotes a shift of the transformation temperature. The change of entropy has been estimated on the basis of Clausius-Clapeyron type equation.

Pastor, J. M.; Pérez-Landazábal, J. I.; Gómez-Polo, C.; Recarte, V.; Larumbe, S.; Santamarta, R.; Fernandes Silva, M.; Gómez Pineda, E. A.; Winkler Hechenleitner, A. A.; Lima, M. K.

2012-02-01

54

Magnetic field-induced direct–indirect crossover in AlxGa1?xAs  

NASA Astrophysics Data System (ADS)

We induce a direct–indirect band gap crossover in a single AlxGa1?xAs sample by using high magnetic fields. A reduction in the photoluminescence (PL) peak energy and onset of an asymmetric peak lineshape at magnetic fields >38 T result from a competition between the radiative recombination lifetime and the carrier migration time as the alloy becomes indirect. By analyzing the progression of the PL lineshape as the magnetic field is increased we show that the crossover is an alloy disorder-broadened, first-order phase transition.

Alberi, Kirstin; Mialitsin, Aleksej V.; Fluegel, Brian; Crooker, Scott A.; Reno, John L.; Mascarenhas, Angelo

2014-11-01

55

Magnetic field-induced dissipation-free state in superconducting nanostructures.  

PubMed

A superconductor in a magnetic field acquires a finite electrical resistance caused by vortex motion. A quest to immobilize vortices and recover zero resistance at high fields made intense studies of vortex pinning one of the mainstreams of superconducting research. Yet, the decades of efforts resulted in a realization that even promising nanostructures, utilizing vortex matching, cannot withstand high vortex density at large magnetic fields. Here, we report a giant reentrance of vortex pinning induced by increasing magnetic field in a W-based nanowire and a TiN-perforated film densely populated with vortices. We find an extended range of zero resistance with vortex motion arrested by self-induced collective traps. The latter emerge due to order parameter suppression by vortices confined in narrow constrictions by surface superconductivity. Our findings show that geometric restrictions can radically change magnetic properties of superconductors and reverse detrimental effects of magnetic field. PMID:23385582

Córdoba, R; Baturina, T I; Sesé, J; Mironov, A Yu; De Teresa, J M; Ibarra, M R; Nasimov, D A; Gutakovskii, A K; Latyshev, A V; Guillamón, I; Suderow, H; Vieira, S; Baklanov, M R; Palacios, J J; Vinokur, V M

2013-01-01

56

Quadrupolar Ordering in LaMnO3 Revealed from Scattering Data and Geometric Modeling A. Sartbaeva, S. A. Wells, and M. F. Thorpe  

E-print Network

in the crystallographic average structure. The ordering of these quadrupoles is important in determining the properties ordering pattern. In manganite perovskites and layered cuprates [2­5], strong Jahn-Teller (JT) coupling [5­12] gives rise to a variety of interesting magnetic, electronic, and structural phenomena such as charge

Thorpe, Michael

57

Magnetic field induced enlargement of the regime of critical fluctuations in the classical superconductor V3Si from high-resolution specific heat experiments.  

PubMed

We present high-resolution specific heat data from a high-purity single crystal of the classical superconductor V3Si, which reveal tiny lambda-shape anomalies at the superconducting transition superimposed onto the BCS specific heat jump in magnetic fields of 2 T and higher. The appearance of these anomalies is accompanied by a magnetic-field-induced broadening of the superconducting transition. We demonstrate, using scaling relations predicted by the fluctuation models of the 3d-XY and the 3d-lowest-Landau-level (3d-LLL) universality class that the effect of critical fluctuations becomes experimentally observable due to of a magnetic field-induced enlargement of the regime of critical fluctuations. The scaling indicates that a reduction of the effective dimensionality due to the confinement of quasiparticles into low Landau levels is responsible for this effect. PMID:25640214

Zheng, Y; Liu, Y; Toyota, N; Lortz, R

2015-02-25

58

Analytical expressions and lineshape simulations for Levitt-Suter-Ernst composite-pulse quadrupolar echo sequences  

NASA Astrophysics Data System (ADS)

Analytical expressions are derived for the Levitt-Suter-Emst composite quadrupolar echo sequences, allowing facile lineshape calculations for comparison with experiment. Large phase distortions in the lineshape obtained with the first-order sequence are significantly reduced with the second-order sequence. For 90° pulse lengths greater than ˜5?s, both sequences produce large phase errors for typical 2H quadrupolar coupling strengths in solids.

Barbara, Thomas M.

59

Quantum manipulation on the Barium quadrupolar transition  

E-print Network

Quantum manipulation on the Barium quadrupolar transition A diploma thesis in physics submitted and stabilization of a new fiber laser system to ma- nipulate the Barium quadrupolar transition, with the aim with a single Barium ion trapped in a linear Paul trap and Doppler cooled to the Lamb Dicke regime. The narrow

Blatt, Rainer

60

Magnetic field-induced elastic bending in bilayers of Tb1-xDyxFe2-y and Pb(Zr1-zTiz)O3  

NASA Astrophysics Data System (ADS)

Magnetic field-induced strain in the magnetoelectric bilayers of Tb1-xDyxFe2-y and Pb(Zr1-zTiz)O3 was studied. A butterfly shaped strain curve was observed on the surface of Pb(Zr1-zTiz)O3. The shape of the strain curve was found to be related to the sample thickness and the volume fraction occupied by the ferroelectrics in the bilayer. Theoretical analysis and experimental results showed that magnetoelastic bending in the bilayer composites was largely responsible for the butterfly strain curve.

Jin, Tao; qichao, Wu; Ning, Zhang

2014-09-01

61

Probing Quadrupolar Nuclei by Solid-State NMR Spectroscopy: Recent Advances  

SciTech Connect

Solid-state nuclear magnetic resonance (NMR) of quadrupolar nuclei has recently undergone remarkable development of capabilities for obtaining structural and dynamic information at the molecular level. This review summarizes the key achievements attained during the last couple of decades in solid-state NMR of both integer spin and half-integer spin quadrupolar nuclei. We provide a concise description of the first- and second-order quadrupolar interactions, and their effect on the static and magic angle spinning (MAS) spectra. Methods are explained for efficient excitation of single- and multiple-quantum coherences, and acquisition of spectra under low- and high-resolution conditions. Most of all, we present a coherent, comparative description of the high-resolution methods for half-integer quadrupolar nuclei, including double rotation (DOR), dynamic angle spinning (DAS), multiple-quantum magic angle spinning (MQMAS), and satellite transition magic angle spinning (STMAS). Also highlighted are methods for processing and analysis of the spectra. Finally, we review methods for probing the heteronuclear and homonuclear correlations between the quadrupolar nuclei and their quadrupolar or spin-1/2 neighbors.

Fernandez, Christian; Pruski, Marek

2011-06-08

62

Magnetic field induced orientation of photosynthetic reaction centers as revealed by time-resolved D-band electron paramagnetic resonance of spin-correlated radical pairs. II. Field dependence of the alignment.  

SciTech Connect

The magnetic-field-induced orientation of photosynthetic reaction centers has been studied by time-resolved D-band (130 GHz) electron paramagnetic resonance (EPR) of the secondary radical pair, P{sup +}{sub 700} A{sup -}{sub 1}, in plant photosystem I (PSI). Experiments have been performed for fresh and lyophilized whole cells of the deuterated cyanobacterium S. lividus. A computer fit of the angle-dependent D-band spectra, measured for two different sample orientations, provides the order parameter S{sub Z'Z'} of the symmetry axis, Z', of the susceptibility tensor, relative to the magnetic field. The positive sign of this order parameter indicates that membrane proteins are the major source for the anisotropy of the diamagnetic susceptibility, {Delta}{chi}V. A value for {Delta}{chi}V has been extracted from the magnetic-field dependence of S{sub Z'Z'}. The value of {Delta}{chi}V = 5.7 x 10{sup -27} m{sup 3} is in good agreement with an estimate for the susceptibility anisotropy of a cyanobacterial cell. This demonstrates that whole cells are aligned in the magneto-orientation process. The combination of high-field EPR of a magnetically oriented sample with the analysis of quantum beat oscillations allows determination of the three-dimensional structure of P{sup +}{sub 700}A{sup -}{sub 1}in the photosynthetic membrane.

Heinen, U.; Poluektov, O.; Stavitski, E.; Berthold, T.; Ohmes, E.; Schlesselman, S. L.; Golecki, J. R.; Moro, G. J.; Levanon, H.; Thurnauer, M. C.; Kothe, G.; Chemistry; Univ. of Freiburg; Hebrew Univ.; Univ. of Padova

2004-07-08

63

Quadrupolar magnetoresistor based on electroconductive magnetorheological elastomer  

Microsoft Academic Search

The quadrupolar magnetoresistor presented in this paper is based on the electroconductive magnetorheological elastomer (MRE) such as discussed in this paper. It is shown that the electric resistances on each pair of terminals of the magnetoresistor can be controlled by an external magnetic field. The results obtained are able to serve for several applications.

Ioan Bica

2009-01-01

64

Optically detected nuclear quadrupolar interaction of 14N in nitrogen-vacancy centers in diamond  

E-print Network

We report sensitive detection of the nuclear quadrupolar interaction of the 14N nuclear spin of the nitrogen-vacancy (NV) center using the electron spin echo envelope modulation technique. We applied a weak transverse magnetic field to the spin system so that certain forbidden transitions became weakly allowed due to second-order effects involving the nonsecular terms of the hyperfine interaction. The weak transitions cause modulation of the electron spin-echo signal, and a theoretical analysis suggests that the modulation frequency is primarily determined by the nuclear quadrupolar frequency; numerical simulations confirm the analytical results and show excellent quantitative agreement with experiments. This is an experimentally simple method of detecting quadrupolar interactions, and it can be used to study spin systems with an energy structure similar to that of the nitrogen vacancy center.

Chang S. Shin; Mark C. Butler; Hai-Jing Wang; Claudia E. Avalos; Scott J. Seltzer; Ren-Bao Liu; Alexander Pines; Vikram S. Bajaj

2014-05-01

65

Magnetic-field-induced twin boundary motion in magnetic shape-memory alloys Harsh Deep Chopra* and Chunhai Ji  

E-print Network

memory alloys, using the Ni-Mn-Ga Heusler alloys. In a martensitically transformed Ni2 xMn1 xGa single. Recent attention has primarily focused on the ferromag- netic Ni2 xMn1 xGa Heusler alloys and the Fe-Pd alloy system.2­4 In particular, the stoichiometric Heusler alloy Ni2MnGa is highly ordered and has

Chopra, Harsh Deep

66

Neutron diffraction study of the magnetic-field-induced transition in Mn{sub 3}GaC  

SciTech Connect

The antiperovskite Mn{sub 3}GaC undergoes an isostructural cubic–cubic first order transition from a low-temperature, large-cell-volume antiferromagnetic state to a high-temperature, small-cell-volume ferromagnetic state at around 160?K. The transition can also be induced by applying a magnetic field. We study here the isothermal magnetic-field-evolution of the transition as ferromagnetism is stabilized at the expense of antiferromagnetism. We make use of the presence of the two distinct cell volumes of the two magnetic states as a probe to observe by neutron diffraction the evolution of the transition, as the external magnetic field carries the system from the antiferromagnetic to the ferromagnetic state. We show that the large-volume antiferromagnetic and the small-volume ferromagnetic states coexist in the temperature range of the transition. The ferromagnetic state is progressively stabilized as the field increases.

Çakir, Ö. [Physics Department, Yildiz Technical University, TR-34220 Esenler, Istanbul (Turkey); Physics Engineering Department, Ankara University, TR-06100 Ankara (Turkey); Acet, M.; Farle, M. [Faculty of Physics and CENIDE, Universität Duisburg-Essen, D-47048 Duisburg (Germany); Senyshyn, A. [Forschungsneutronenquelle Heinz Maier-Leibnitz FRM-II, Technische Universität München, D-85747 Garching bei München (Germany)

2014-01-28

67

Nature of magnetism and magnetic-field-induced transitions in non-collinear antiferromagnet Er2O3  

NASA Astrophysics Data System (ADS)

The nature of magnetism in Er2O3 is investigated by detailed studies of the temperature (2-300 K) and magnetic field (up to 90 kOe) dependence of the magnetization M of powder sample of Er2O3. The results show paramagnetic to antiferromagnetic (AFM) transition occurring at TN=3.3 K. For T>TN the magnetic susceptibility vs. temperature data follows the Curie-Weiss (?=C/(T-?)) variation with ?=-10.2 K and magnetic moment ?=6.68 ?B/Er ion determined from C. Molecular field model is used to determine the nn (nnn) exchange constants J1(J2)=-0.57 K (-3.38 K). The M vs. H data at 2 K analyzed in terms of dM/dH vs. H variations show two field-induced transitions, the first one at HSF?15 kOe and the second one at HS?31 kOe. Arguments and analysis are presented to show that HSF represents the spin-flop transition whereas for H>HS, the system is field-aligned ferromagnetically since the calculated value of HS for ferromagnetic ordering using the above magnitudes of J1 and J2 agrees well with the experimental HS. The temperature dependence of HSF is shown to follow the normalized Brillouin function variation for spin S=1/2 valid for Er2O3. The magnetic field dependence of TN is measured and shown to follow the equation: TN(H)=TN(0)-D1H2, expected for antiferromagnets.

Narang, V.; Korakakis, D.; Seehra, M. S.

2014-11-01

68

Formation of ordered films of axially bridged aluminum phthalocyanine [(tBu){sub 4}PcAl]{sub 2}O via magnetic field-induced reaction  

SciTech Connect

The ?-(oxo)bis[tetra-tert-butylphthalocyaninato] aluminum(III) [(tBu){sub 4}PcAl]{sub 2}O films with the crystallites oriented preferably in one direction were obtained via chemical transformation of tetra-tert-butylsubstituted chloroaluminum(III) phthalocyanine (tBu){sub 4}PcAlCl film upon its annealing in magnetic field. A comparative analysis of the influence of post-deposition annealing process without and under applied magnetic field of 1 T, on the orientation and morphology of (tBu){sub 4}PcAlCl and [(tBu){sub 4}PcAl]{sub 2}O films, has been carried out by the methods of UV-vis, Infrared and Raman spectroscopies, XRD as well as atomic force microscopy. The formation of [(tBu){sub 4}PcAl]{sub 2}O films with elongated crystallites having preferential orientation was observed upon heating of the films in magnetic field while annealing without magnetic field under the same conditions does not demonstrate any effect on the structure and morphology of these films. The reasons of the sensitivity of this reaction to the presence of such magnetic field is discussed and studied by electronic paramagnetic resonance spectroscopy.

Basova, Tamara, E-mail: basova@niic.nsc.ru; Berezin, Aleksei; Nadolinny, Vladimir [Nikolaev Institute of Inorganic Chemistry, Russian Academy of Sciences, Lavrentiev Pr., 3, 630090 Novosibirsk (Russian Federation)] [Nikolaev Institute of Inorganic Chemistry, Russian Academy of Sciences, Lavrentiev Pr., 3, 630090 Novosibirsk (Russian Federation); Peisert, Heiko; Chassé, Thomas [Institute for Physical and Theoretical Chemistry, Auf der Morgenstelle 18, 72076 Tübingen (Germany)] [Institute for Physical and Theoretical Chemistry, Auf der Morgenstelle 18, 72076 Tübingen (Germany); Banimuslem, Hikmat; Hassan, Aseel [Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom)] [Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom)

2013-11-28

69

Investigation of the effect of a variety of pulse errors on spin I=1 quadrupolar alignment echo spectroscopy.  

PubMed

We report on an analysis of a well known three-pulse sequence for generating and detecting spin I=1 quadrupolar order when various pulse errors are taken into account. In the situation of a single quadrupolar frequency, such as the case found in a single crystal, we studied the potential leakage of single and/or double quantum coherence when a pulse flip error, finite pulse width effect, RF transient or a resonance offset is present. Our analysis demonstrates that the four-step phase cycling scheme studied is robust in suppressing unwanted double and single quantum coherence as well as Zeeman order that arise from the experimental artifacts, allowing for an unbiased measurement of the quadrupolar alignment relaxation time, T(1Q). This work also reports on distortions in quadrupolar alignment echo spectra in the presence of experimental artifacts in the situation of a powdered sample, by simulation. Using our simulation tool, it is demonstrated that the spectral distortions associated with the pulse artifacts may be minimized, to some extent, by optimally choosing the time between the first two pulses. We highlight experimental results acquired on perdeuterated hexamethylbenzene and polyethylene that demonstrate the efficacy of the phase cycling scheme for suppressing unwanted quantum coherence when measuring T(1Q). It is suggested that one employ two separate pulse sequences when measuring T(1Q) to properly analyze the short time behavior of quadrupolar alignment relaxation data. PMID:21664160

Ma, Xiang; Sun, Cheng; Boutis, Gregory S

2011-08-01

70

Quadrupolar Interactions in Praseodymium - SILVER(1 - Copper(x)  

NASA Astrophysics Data System (ADS)

We have utilized magnetization, specific heat, resistivity and diffraction experiments (each as a function of applied magnetic field and temperature) to investigate the magnetic properties of the series of pseudo-binary rare earth-intermetallic compounds PrAg(,1-x)Cu(,x) (for x = 0, 0.15, 0.25, 0.35, 0.4, 0.5, 0.75 and 1.0). For 0 <= x <= 0.4, the samples possess a CsCl -type (cubic) crystal structure and exhibit antiferromagnetic ordering at low temperatures (T(,N) < 11K), as revealed by x-ray and neutron diffraction and magnetization measurements. For x = 0.75 and 1.0, the crystal structure is FeB-type (orthorhombic) and no magnetic ordering occurs for T > 2K. For x = 0.5, the sample undergoes a structural transition from CsCl - to FeB-type upon cooling below 160K. Analysis of magnetization measurements reveals that, in addition to the typical bilinear exchange interactions, the CsCl-type compounds also possess effective negative quadrupolar interactions which increase in magnitude by a factor of five as x increases from 0 to 0.4. Such negative (antiferroquadropolar) interactions favor quadrature alignment of neighboring quadrupoles. Specific heat and resistivity measurements indicate that the magnetic order-disorder transition for x = 0 is a typical antiferromagnetic-paramagnetic transition, displaying a sharp peak in C(,m) vs T and a well-defined spin-disorder contribution to the resistivity. As x increases, however, the peak in the magnetic specific heat broadens and decreases in magnitude, accompanied by a change in the rate of development of entropy and a change in the nature of the magnetic excitations in the ordered state. In addition, the change in the resistivity at the magnetic transition becomes more gradual, and the apparent spin-disorder terms becomes a factor of four smaller. The effective quadrupolar interactions in these systems linked to incipient structural instabilities in the CsCl-type structure which ultimately lead to the structural transition for large enough x, with the interactions resulting from a Jahn-Teller-type coupling to zone boundary phonons which are presume to soften as the compounds approach the critical composition. The resulting competition between the bilinear and antiferroquadrupolar interactions modifies the nature of the magnetic phase transition.

Gotaas, James Alan

71

Fundamental measure density functional theory study of liquid-vapor interface of dipolar and quadrupolar fluids.  

PubMed

We have studied interfacial structure and properties of liquid-vapor interfaces of dipolar fluids and quadrupolar fluids, respectively, using the classical density functional theory (DFT). Towards this end, we employ the fundamental measure DFT for a reference hard-sphere (HS) part of free energy and the modified mean field approximation for the correlation function of dipolar or quadrupolar fluid. At low temperatures we find that both the liquid-vapor interfacial density profile and orientational order parameter profile exhibit weakly damped oscillatory decay into the bulk liquid. At high temperatures the decay of interfacial density and order parameter profiles is entirely monotonic. The scaled temperature ? = 1 - T/T(c) that separates the two qualitatively different interfacial structures is in the range 0.10-0.15. At a given (dimensionless) temperature, increasing the dipolar or quadrupolar moment enhances the density oscillations. Application of an electric field (normal to the interface) will damp the oscillations. Likewise, at the given temperature, increasing the strength of any multipolar moment also increases the surface tensions while increasing the strength of the applied electric field will reduce the surface tensions. The results are compared with those based on the local-density approximations (LDA) for the reference HS part of free energy as well as with results of numerical experiments. PMID:24116570

Warshavsky, V B; Zeng, X C

2013-10-01

72

Energetic particles in the paleomagnetosphere: Reduced dipole configurations and quadrupolar  

E-print Network

Energetic particles in the paleomagnetosphere: Reduced dipole configurations and quadrupolar 2007. [1] The Earth's magnetosphere acts as a shield against highly energetic particles of cosmic alter the magnetospheric structure and dynamics. This paper deals with energetic particles

Steinhoff, Heinz-Jürgen

73

Relaxation times of spin states of all ranks and orders of quadrupolar nuclei estimated from NMR z-spectra: Markov chain Monte Carlo analysis applied to 7Li+ and 23Na+ in stretched hydrogels.  

PubMed

The NMR z-spectra of 7Li+ and 23Na+ in stretched hydrogels contain five minima, or critical values, with a sharp "dagger" on the central dip. The mathematical representation of such z-spectra from spin-3/2 nuclei contains nine distinct (the total is 15 but there is redundancy of the ±order-numbers) relaxation rate constants that are unique for each of the spin states, up to rank 3, order 3. We present an approach to multiple-parameter-value estimation that exploits the high level of separability of the effects of each of the relaxation rate constants on the features of the z-spectrum. The Markov chain Monte Carlo (MCMC) method is computationally demanding but it yielded statistically robust estimates (low coefficients of variation) of the parameter values. We describe the implementation of the MCMC analysis (in the present context) and posit that it can obviate the need for using multiple-quantum filtered RF-pulse sequences to estimate all relaxation rate constants/times under experimentally favorable, but readily achievable, circumstances. PMID:21742525

Kuchel, Philip W; Naumann, Christoph; Puckeridge, Max; Chapman, Bogdan E; Szekely, David

2011-09-01

74

Spectroscopic Investigation of Artificial Opals Infiltrated with a Heteroaromatic Quadrupolar Dye  

E-print Network

Spectroscopic Investigation of Artificial Opals Infiltrated with a Heteroaromatic Quadrupolar Dye of polystyrene opals infiltrated with solutions of ad hoc synthesized heteroaromatic quadrupolar dyes endowed with strong nonlinear optical properties (two-photon absorption). Transmittance spectroscopy of opals

75

Kn 26, a new quadrupolar planetary nebula  

NASA Astrophysics Data System (ADS)

Once classified as an emission line source, the planetary nebula (PN) nature of the source Kn 26 has only recently been recognized in digital sky surveys. To investigate the spectral properties and spatio-kinematical structure of Kn 26, we have obtained high spatial-resolution optical and near-IR narrow-band images, high-dispersion long-slit echelle spectra, and intermediate-resolution spectroscopic observations. The new data reveal an hourglass morphology typical of bipolar PNe. A detailed analysis of its morphology and kinematics discloses the presence of a second pair of bipolar lobes, making Kn 26 a new member of the subclass of quadrupolar PNe. The time lapse between the ejection of the two pairs of bipolar lobes is much shorter than their dynamical ages, implying a rapid change in the preferential direction of the central engine. The chemical composition of Kn 26 is particularly unusual among PNe, with a low N/O ratio (as for type II PNe) and a high helium abundance (as for type I PNe), although not atypical among symbiotic stars. Such an anomalous chemical composition may have resulted from the curtailment of the time in the asymptotic giant branch by the evolution of the progenitor star through a common envelope phase. Based on observations made with the Nordic Optical Telescope (NOT) and the William Herschel Telescope (WHT) on the island of La Palma in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias (IAC), the 2.1-m telescope of the Observatorio Astronómico Nacional at the Sierra de San Pedro Mártir (OAN-SPM), and the 1.5-m telescope at the Observatorio de Sierra Nevada (OSN), Granada, Spain. NOT is operated jointly by Denmark, Finland, Iceland, Norway, and Sweden. WHT is operated by the Isaac Newton Group. The 2.1-m telescope at the OAN-SPM is a national facility operated by the Instituto de Astronomía of the Universidad Nacional Autónoma de México. The 1.5-m telescope at the OSN is operated by the Instituto de Astrofísica de Andalucía (IAA).The data presented here were obtained in part with ALFOSC, which is provided by the IAA under a joint agreement with the University of Copenhagen and NOTSA.FITS files for spectra and images are available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/551/A53

Guerrero, M. A.; Miranda, L. F.; Ramos-Larios, G.; Vázquez, R.

2013-03-01

76

Quadrupolar-coupling-specific binomial pulse sequences for in vivo 23Na NMR and MRI  

Microsoft Academic Search

Aimed at selective detection of 23Na with specific quadrupolar couplings for in vitro NMR and MRI, we present a series of quadrupolar binomial pulse sequences offering high specificity with respect to the quadrupolar couplings of the excited species. It is demonstrated that pulse sequences with an increasing number of elements, e.g., 11, 121, 1331, 14641, and 15101051, with the units

Christoffer Laustsen; Steffen Ringgaard; Michael Pedersen; Niels Chr. Nielsen

2010-01-01

77

Quadrupolar, Triple [Delta]-Function Potential in One Dimension  

ERIC Educational Resources Information Center

The energy and parity eigenstates for quadrupolar, triple [delta]-function potential are analysed. Using the analytical solutions in specific domains, simple expressions are obtained for even- and odd-parity bound-state energies. The Heisenberg uncertainty product is observed to have a minimum for a specific strength of the potential. The…

Patil, S. H.

2009-01-01

78

Magnetorheological elastomer-based quadrupolar element of electric circuits  

Microsoft Academic Search

The author of this paper describes a quadrupolar electric circuit element (Q) based on electroconductive magnetorheological elastomer. It is shown by means of the experimental setup presented in the paper, that the electrical resistances, measured at the gates of Q, decrease with the increase of the strength H of the transverse magnetic field. But, for intensities of the control current

Ioan Bica

2010-01-01

79

Quadrupolar correlations and spin freezing in S=1 triangular lattice antiferromagnets  

NASA Astrophysics Data System (ADS)

Motivated by experiments on NiGa2S4 , we discuss characteristic (finite-temperature) properties of spin S=1 quantum antiferromagnets on the triangular lattice. Several recent theoretical studies have suggested the possibility of quadrupolar (spin-nematic) ground states in the presence of sufficient biquadratic exchange. We argue that quadrupolar correlations are substantially more robust than the spin-nematic ground state and give rise to a two-peak structure of the specific heat. We characterize this behavior by a T>0 semiclassical approximation, which is amenable to efficient Monte Carlo simulations. Turning to low temperatures, we consider the effects of weak disorder on incommensurate magnetic order, which is present when interactions beyond nearest-neighbor exchange are substantial. We show that nonmagnetic impurities act as random fields on a component of the order parameter, leading to the disruption of long-range magnetic order even when the defects are arbitrarily weak. Instead, gradual freezing phenomena are expected on lowering the temperature, with no sharp transition but a rapid slowing of dynamics and the development of substantial spin-glass-like correlations. We discuss these observations in relation to measurements of NiGa2S4 .

Stoudenmire, E. M.; Trebst, Simon; Balents, Leon

2009-06-01

80

Quinoline-derived two-photon sensitive quadrupolar probes.  

PubMed

The first quadrupolar 8-dimethylaminoquinoline-derived 6-(8-DMAQ-OAc)2 (1c) and 5-(8-DMAQ-OAc)2 (2c) photosensitive probes underwent photolysis under UV (365 nm) and NIR (730 nm two-photon (TP)) irradiation conditions, showing Qu = 9.3% and 6.6% quantum yields and ?u = 0.07 GM and 0.40 GM uncaging cross-sections, respectively. PMID:25356798

Dunkel, Petra; Tran, Christine; Gallavardin, Thibault; Dhimane, Hamid; Ogden, David; Dalko, Peter I

2014-12-28

81

High-resolution solid-state NMR of quadrupolar nuclei  

Microsoft Academic Search

Quadrupolar nuclei are the most abundant nuclear magnetic resonance (NMR)-receptive nuclei in the Earth's crust, and in many amorphous materials of technological interest (such as zeolite catalysts, ceramics and alloys), and have thus been intensively studied1-7. Of particular interest is the ability to resolve and quantitate the various types of sites present in a given material. Here we present a

Eric Oldfield; Hye Kyung C. Timken; Ben Montez; R. Ramachandran

1985-01-01

82

Vanillin-molecularly targeted extraction of stir bar based on magnetic field induced self-assembly of multifunctional Fe3O4@Polyaniline nanoparticles for detection of vanilla-flavor enhancers in infant milk powders.  

PubMed

A molecularly imprinted stir bar was constructed based on Fe3O4@Polyaniline nanoparticles with magnetic field-induced self-assembly process. The monomer, methacrylic acid, was pre-assembled into the pre-polymers with vanillin as template by the formation of hydrogen bonds. After that, the magnetic complexes were generated by the hydrogen bonding, the hydrophobic and ?-? interaction between the pre-polymers and Fe3O4@Polyaniline. The complexes were adsorbed on the surface of magnetic stir bar under the magnetic induction, and the coating of vanillin-molecularly imprinted polymers was generated by the one-step copolymerization basing on the cross linking of ethylene glycol dimethacrylate. The molecular imprinting stir bar showed superior selectivity and fast binding kinetics for vanillin, and was used for the enrichment of vanilla-flavor enhancers (vanillin, ethyl maltol and methyl vanillin) in infant milk powders. The results measured by HPLC-UV exhibited good linear ranges of 0.01-100, 0.02-100 and 0.03-100?gmL(-1) with the limit of detection of 2.5-10.0ngmL(-1), and the recoveries were 94.7-98.9%, 82.1-96.7% and 84.5-93.2% with RSD<7.2% for the three enhancers, respectively. PMID:25514645

Wu, Jinhua; Yang, Zaiyue; Chen, Ning; Zhu, Wanying; Hong, Junli; Huang, Changgao; Zhou, Xuemin

2015-03-15

83

Two-dimensional nuclear magnetic resonance of quadrupolar systems  

SciTech Connect

This dissertation describes two-dimensional nuclear magnetic resonance theory and experiments which have been developed to study quadruples in the solid state. The technique of multiple-quantum magic-angle spinning (MQMAS) is extensively reviewed and expanded upon in this thesis. Specifically, MQMAS is first compared with another technique, dynamic-angle spinning (DAS). The similarity between the two techniques allows us to extend much of the DAS work to the MQMAS case. Application of MQMAS to a series of aluminum containing materials is then presented. The superior resolution enhancement through MQMAS is exploited to detect the five- and six-coordinated aluminum in many aluminosilicate glasses. Combining the MQMAS method with other experiments, such as HETCOR, greatly expands the possibility of the use of MQMAS to study a large range of problems and is demonstrated in Chapter 5. Finally, the technique switching-angle spinning (SAS) is applied to quadrupolar nuclei to fully characterize a quadrupolar spin system in which all of the 8 NMR parameters are accurately determined. This dissertation is meant to demonstrate that with the combination of two-dimensional NMR concepts and new advanced spinning technologies, a series of multiple-dimensional NMR techniques can be designed to allow a detailed study of quadrupolar nuclei in the solid state.

Wang, Shuanhu

1997-09-17

84

Pair-breaking effect caused by the anion disorder in the magnetic-field-induced spin-density wave: A calorimetric study  

NASA Astrophysics Data System (ADS)

We have investigated the effect of anion disorder on the spin-density wave induced by the magnetic field (FISDW) in (TMTSF)2ClO4 (the TMTSF is the tetramethyltetraselenafulvalene molecule). Specific heat and magnetocaloric-effect measurements have been performed under a magnetic field for various cooling rates across the ordering transition of the ClO4 anions. The respective variations of the critical temperature and of the jump of the electronic specific heat at the metal-SDW transition are compared with the universal pair-breaking behavior of a Bardeen-Cooper-Schrieffer superconductor in the presence of magnetic impurities. The field-induced spin-density wave (FISDW), in the presence of nonmagnetic anion disorder, qualitatively behaves as the former but exhibits a stronger pair-breaking effect. The anion disorder is also shown to be responsible for the change in the criticality of the metal-SDW phase transition: a peculiar point in the phase diagram is found to evolve from tetracritical to bicritical as the anion disorder is increased. These behaviors are discussed in light of available models for the spin-density wave induced by the magnetic field.

Tsobnang, F.; Pesty, F.; Garoche, P.

1994-06-01

85

Multiple-quantum cross-polarization and two-dimensional MQMAS NMR of quadrupolar nuclei.  

PubMed

Cross-polarization from (1)H to the multiple-quantum coherences of a quadrupolar nucleus is used in combination with the two-dimensional multiple-quantum magic angle spinning (MQMAS) NMR experiment in order to extract high-resolution CPMAS NMR spectra. The technique is demonstrated on (23)Na (S = 3/2), (17)O, (27)Al (both S = 5/2), and (45)Sc (S = 7/2) nuclei, showing the applicability of multiple-quantum cross-polarization to systems with differing spin quantum number, gyromagnetic ratio, and relative nuclide abundance. The utility of this two-dimensional MAS NMR experiment for spectral editing and site-specific measurement of cross-polarization intensities is demonstrated. The possibility of direct cross-polarization to higher order multiple-quantum coherences is also considered and three-, five-, and seven-quantum cross-polarized (45)Sc MAS NMR spectra are presented. PMID:11097815

Ashbrook, S E; Wimperis, S

2000-12-01

86

Fluctuating magnetic field induced resonant activation.  

PubMed

In this paper, we have studied the properties of a Brownian particle at stationary state in the presence of a fluctuating magnetic field. Time dependence of the field makes the system thermodynamically open. As a signature of that the steady state distribution function becomes function of damping strength, intensity of fluctuations and constant parts of the applied magnetic field. It also depends on the correlation time of the fluctuating magnetic field. Our another observation is that the random magnetic field can induce the resonant activation phenomenon. Here correlation time is increased under the fixed variance of the fluctuating field. But if the correlation time (?) increases under the fixed field strength then the mean first passage time rapidly grows at low ? and it almost converges at other limit. This is sharp contrast to the usual colored noise driven open system case where the mean first passage time diverges exponentially. We have also observed that a giant enhancement of barrier crossing rate occurs particularly at large strength of constant parts of the applied magnetic field even for very weak fluctuating magnetic field. Finally, break down of the Arrhenius result and disappearance of the Kramers' turn over phenomenon may occur in the presence of a fluctuating magnetic field. PMID:25494726

Mondal, Shrabani; Das, Sudip; Baura, Alendu; Bag, Bidhan Chandra

2014-12-14

87

Fluctuating magnetic field induced resonant activation  

NASA Astrophysics Data System (ADS)

In this paper, we have studied the properties of a Brownian particle at stationary state in the presence of a fluctuating magnetic field. Time dependence of the field makes the system thermodynamically open. As a signature of that the steady state distribution function becomes function of damping strength, intensity of fluctuations and constant parts of the applied magnetic field. It also depends on the correlation time of the fluctuating magnetic field. Our another observation is that the random magnetic field can induce the resonant activation phenomenon. Here correlation time is increased under the fixed variance of the fluctuating field. But if the correlation time (?) increases under the fixed field strength then the mean first passage time rapidly grows at low ? and it almost converges at other limit. This is sharp contrast to the usual colored noise driven open system case where the mean first passage time diverges exponentially. We have also observed that a giant enhancement of barrier crossing rate occurs particularly at large strength of constant parts of the applied magnetic field even for very weak fluctuating magnetic field. Finally, break down of the Arrhenius result and disappearance of the Kramers' turn over phenomenon may occur in the presence of a fluctuating magnetic field.

Mondal, Shrabani; Das, Sudip; Baura, Alendu; Bag, Bidhan Chandra

2014-12-01

88

On the relationship between quadrupolar magnetic field and collisionless reconnection  

SciTech Connect

Using hybrid simulations, we investigate the onset of fast reconnection between two cylindrical magnetic shells initially close to each other. This initial state mimics the plasma structure in High Energy Density Plasmas induced by a laser-target interaction and the associated self-generated magnetic field. We clearly observe that the classical quadrupolar structure of the out-of-plane magnetic field appears prior to the reconnection onset. Furthermore, a parametric study reveals that, with a non-coplanar initial magnetic topology, the reconnection onset is delayed and possibly suppressed. The relation between the out-of-plane magnetic field and the out-of-plane electric field is discussed.

Smets, R., E-mail: roch.smets@lpp.polytechnique.fr; Belmont, G. [LPP, University P. and M. Curie, CNRS, Ecole Polytechnique, F-91128 Palaiseau (France); Aunai, N. [IRAP, University Paul Sabatier, F-31028 Toulouse (France); Boniface, C. [CEA/DAM, DIF, F-91297 Arpajon (France); Fuchs, J. [LULI, Ecole Polytechnique, CNRS, CEA, University P. and M. Curie, F-91128 Palaiseau (France)

2014-06-15

89

Quadrupolar Kondo effect in uranium heavy-electron materials?  

NASA Technical Reports Server (NTRS)

The possibility of an electric quadrupole Kondo effect for a non-Kramers doublet on a uranium (U) ion is a cubic metallic host is demonstrated by model calculations showing a Kondo upturn in the resistivity, universal quenching of the quadrupolar moment, and a heavy-electron anomaly in the electronic specific heat. With inclusion of excited crystal-field levels, some of the unusual magnetic-response data in the heavy-electron superconductor UBe13 may be understood. Structural phase transitions at unprecedented low temperatures may occur in U-based heavy-electron materials.

Cox, D. L.

1987-01-01

90

A simple theoretical treatment of quadrupolar effects on magic-angle-spinning solid-state NMR spectra of spin-1/2 nuclei in the limit of large quadrupole coupling constants.  

PubMed

A simple approach is discussed for studying the effect of quadrupolar nuclei on the magic-angle-spinning solid-state NMR lines of spin-1/2 nuclei in the limit of large quadrupole coupling constants. Equations are derived both for the isotropic shifts and the Pake-like powder patterns for any quadrupolar spin and for arbitrary orientations of the internuclear vector with respect to the unique axis of an axially symmetric quadrupole tensor. First-order effects due to a small Zeeman perturbation on these lines are explored, as well as deviations from axial symmetry in the electric field gradient when S = 3/2 quadrupolar nuclei are involved. Spectral parameters likely to be observed in the case of coupling between 31P and 201Hg are also discussed. PMID:7834309

Olivieri, A C

1993-03-01

91

The Percus-Yevick approximation for quadrupolar molecular fluids  

NASA Astrophysics Data System (ADS)

The Percus-Yevick integral equation theory has been solved to study the equilibrium and structural properties of quadrupolar Gay-Berne fluids. The method used involves an expansion of angle-dependent functions appearing in the integral equations in terms of spherical harmonics and the harmonic coefficients are obtained by an iterative algorithm. All the terms of harmonic coefficients which involve l indices up to less than or equal to 6 have been considered. Molecules with length-to-breadth ratios 3.0 and 4.0 have been considered and results are reported for different densities, temperatures, and quadrupole moments. The values of pair correlation functions have been compared with the available computer simulation results.

Singh, Ram Chandra; Mohan Singh, Braj; Ram, Jokhan

2009-03-01

92

Quadrupolar-fluctuation model for high-Tc superconductivity: A quantum Monte Carlo study  

Microsoft Academic Search

We present results for quantum Monte Carlo simulations of the quadrupolar fluctuation model of high-temperature superconductivity. The simulations focused on measurement of the pairing susceptibility in various interesting pairing channels (on-site, nearest-neighbor, and second-nearest-neighbor s- and d-wave pairing). The lattice was 4×4 in the oxygen sites, with eight copper sites bearing quadrupole moments. Exchange of these quadrupolar fluctuations may lead

M. Jarrell; D. L. Cox

1990-01-01

93

Hybridized effects of plasmonic quadrupolar and dipolar resonances on the perforated planar metallic film  

NASA Astrophysics Data System (ADS)

We have designed a detuned double-L-shaped nanohole arrays in the metallic film, on which the hybridized plasmonic quadrupolar and dipolar resonance modes can be excited by the incident light, respectively. Compared with the conventional plasmonic resonance modes, the antibonding quadrupolar resonance mode has a higher quality factor due to its lower radiative loss. A quality factor of 38 (theoretical prediction exceeding 100) is obtained in the experiment.

Wu, Shan; Zhou, Lin; Wang, Qianjin; Zhang, Xuejin; Zhu, Yongyuan

2013-02-01

94

Quadrupolar spectra of nuclear spins in strained InxGa1-xAs quantum dots  

NASA Astrophysics Data System (ADS)

Self-assembled quantum dots (QDs) are born out of lattice mismatched ingredients where strain plays an indispensable role. Through the electric quadrupolar coupling, strain affects the magnetic environment as seen by the nuclear spins. To guide prospective single-QD nuclear magnetic resonance (NMR), as well as dynamic nuclear spin polarization experiments, an atomistic insight to the strain and quadrupolar field distributions is presented. A number of implications of the structural and compositional profile of the QD have been identified. A high aspect ratio of the QD geometry enhances the quadrupolar interaction. The inclined interfaces introduce biaxiality and the tilting of the major quadrupolar principal axis away from the growth axis; the alloy mixing of gallium into the QD enhances both of these features while reducing the quadrupolar energy. Regarding the NMR spectra, both Faraday and Voigt geometries are investigated, unraveling in the first place the extend of inhomogeneous broadening and the appearance of the normally forbidden transitions. Moreover, it is shown that from the main extend of the NMR spectra the alloy mole fraction of a single QD can be inferred. By means of the element-resolved NMR intensities it is found that In nuclei has a factor of 5 dominance over those of As. In the presence of an external magnetic field, the borderlines between the quadrupolar and Zeeman regimes are extracted as 1.5 T for In and 1.1 T for As nuclei. At these values the nuclear spin depolarization rates of the respective nuclei get maximized due to the noncollinear secular hyperfine interaction with a resident electron in the QD.

Bulutay, Ceyhun

2012-03-01

95

Recent advances in solid-state NMR spectroscopy of quadrupolar nuclei.  

PubMed

Nuclear magnetic resonance (NMR) spectroscopy of quadrupolar nuclei (i.e., those with a spin quantum number I > 1/2) has always been viewed as "difficult" owing to the presence of an anisotropic broadening arising from the interaction of the nuclear electric quadrupole moment with the electric field gradient. This quadrupolar interaction can be considerable, resulting in broadening of the spectral resonances often over many MHz. Furthermore, magic-angle spinning (MAS), a conventional approach for increasing the resolution in solid-state NMR, is often unable to remove the broadening completely and high-resolution spectra are generally not obtained. Despite the vast amount of information contained in the anisotropic linewidths and lineshapes, the resolution and sensitivity challenges have, until recently, somewhat limited the application of solid-state NMR for quadrupolar nuclei. In general, structural information, such as that obtained through recoupling techniques or from two-dimensional correlation spectroscopy, is much more difficult to extract easily and accurately. However, recent advances in magnet design, probe hardware and pulse sequence development have significantly improved the ease with which quadrupolar spins can be studied and high-resolution spectra can be obtained, and recent applications are beginning to exploit the wealth of information available. In this discussion, we highlight just a few of the recent developments in this area, including new state-of-the art correlation experiments, the expanding study of nuclei with low gyromagnetic ratio, gamma, the increasing application of first-principles calculations in the solid state, and methods which exploit the quadrupolar broadening to provide information on dynamics. Whilst not a complete review, it is hoped that this brief overview of some of the more exciting recent developments can provide insight into the challenges, and the rewards, involved in the NMR study of quadrupolar nuclei. PMID:19652823

Ashbrook, Sharon E

2009-08-28

96

NMR and NQR studies of quadrupolar effects in glasses and polycrystals with half-integer spins  

NASA Astrophysics Data System (ADS)

NMR and NQR techniques have been used in the present study to investigate glasses and polycrystalline compounds containing nuclei with half-integer spins such as: sp{11}B, sp{23}Na, sp{45}Sc, and sp{93}Nb. The low field ({˜}1.2{-}1.5 Tesla) continuous wave (CW) NMR experiments were performed using the Non-Adiabatic Superfast Passage (NASP) or the slow passage methods. A BRUKER MSL 300 pulsed NMR spectrometer was used for the high field (7.1 Tesla) studies. The CW NQR experiments at room and liquid nitrogen temperature were carried out on a home built Robinson-type spectrometer. Using pulsed NMR the sp{45}Sc response from the glass system CaO-Bsb2Osb3-Scsb2Osb3, yielded a first-order quadrupolar interaction with eta=0 and Qsb{cc}?617 kHz. A new Sc site with Qsb{cc}=23.44 MHz and eta=0 was found in polycrystalline Scsb2Osb3 and it was confirmed by NQR. Employing the NASP method it was found that the fraction of four-coordinated (Nsb4) boron atoms in the alkali thioborate (Nasb2S-Bsb2Ssb3) glass system follows a 3x/(1 - x) relationship for x?0.15, where x is the molar fraction of Nasb2S in the glass. For the NQR spectra the 10% Nasb2S content glass exhibited a broader NQR resonance than the NQR resonance for pure v-Bsb2Ssb3. The additional width was attributed to responses of BSsb3 units whose Qsb{cc} values differ somewhat from the BSsb3 units in the pure vitreous Bsb2Ssb3. The CW NASP method was used to study the sp{23}Na response in the Nasb2O*2SiOsb2 glass, heat treated in three ways: annealed, slow cooled and splat quenched. Subjecting the glass to rapid cooling will produce an increased range of values for the components of the electric field gradient (EFG), and, hence an increased range of values for Qsb{cc} and eta. This was observed for the slow cooled sample when compared with the annealed glass. The effect should be seen also from the slow cooled to the splat quenched sample, but this was not observed. Crystalline sodium disilicate was examined by both NMR and NQR and yielded Qsb{cc} = 1.89 MHz for sp{23}Na and eta=0.9. Furthermore the response from sp{23}Na in the polycrystalline forms of sodium molybdate, sodium tungstate, sodium stanate and albite was examined by means of NASP, pulsed NMR, and NQR. The sp{23}Na spectra for these compounds yielded values of Qsb{cc}, in the range 2.56 MHz to 2.80 MHz. A computer simulation program was used to simulate the spectra of sp{93}Nb-containing compounds. The survey of the niobium response in various polycrystalline compounds using the pulse-echo technique revealed first-order and second-order quadrupolar effects. The sp{93}Nb responses from five glasses in the Nbsb2Osb5-Nasb2O-SiOsb2 ternary glass system produced a second-order quadrupole pattern, but the response might contain more than one Nb site.

Orengo-Aviles, Moises

97

Multiple-Quantum Cross Polarization in Quadrupolar Spin Systems during Magic-Angle Spinning1  

E-print Network

Multiple-Quantum Cross Polarization in Quadrupolar Spin Systems during Magic-Angle Spinning1 David-quantum cross polarization (CP) between an I 3 2 and an I 1 2 spin during magic-angle spinning. Experimental and are intimately involved in many chemical, physical, and biological processes (1). Until recently, these spin

Griffin, Robert G.

98

Homonuclear NMR Correlations between Half-Integer Quadrupolar Nuclei Undergoing Magic-Angle Spinning  

E-print Network

-Angle Spinning Mattias Ede´n and Lucio Frydman* Chemical Physics Department, Weizmann Institute of Science, Reho-integer quadrupolar nuclei undergoing magic-angle-spinning (MAS). Various spin interactions that do not commute in the application of solid-state nuclear magnetic resonance (NMR) techniques on nuclei possessing a spin S > 1

Frydman, Lucio

99

Quadrupolar and Chemical Shift Tensors Characterized by 2D Multiple-Quantum NMR Spectroscopy  

E-print Network

. The technique exploits the different contribu- tions that quadrupolar and shielding interactions impart by the role that such elements play in many important materials such as min- erals, ceramics, glasses by the shielding coupling tensor parameters. In spite of the potential relevance that the combined mea- surement

Frydman, Lucio

100

Quadrupolar-fluctuation model for high- T sub c superconductivity: A quantum Monte Carlo study  

SciTech Connect

We present results for quantum Monte Carlo simulations of the quadrupolar fluctuation model of high-temperature superconductivity. The simulations focused on measurement of the pairing susceptibility in various interesting pairing channels (on-site, nearest-neighbor, and second-nearest-neighbor {ital s}- and {ital d}-wave pairing). The lattice was 4{times}4 in the oxygen sites, with eight copper sites bearing quadrupole moments. Exchange of these quadrupolar fluctuations may lead to attraction between oxygen holes. As in weak-coupling theory, we find (i) favorable tendencies towards second-nearest-neighbor {ital s}- and {ital d}-wave filling, with larger doping favoring {ital d}-wave symmetry; (ii) a nonmonotonic dependence of the pairing tendencies upon the on-site quadrupole level splitting; and (iii) a strong suppression of all nearest-neighbor pairing.

Jarrell, M.; Cox, D.L. (Department of Physics, The Ohio State University, 174 West 18th Avenue, Columbus, OH (USA))

1990-11-01

101

Quadrupolar-fluctuation model for high-Tc superconductivity: A quantum Monte Carlo study  

NASA Astrophysics Data System (ADS)

We present results for quantum Monte Carlo simulations of the quadrupolar fluctuation model of high-temperature superconductivity. The simulations focused on measurement of the pairing susceptibility in various interesting pairing channels (on-site, nearest-neighbor, and second-nearest-neighbor s- and d-wave pairing). The lattice was 4×4 in the oxygen sites, with eight copper sites bearing quadrupole moments. Exchange of these quadrupolar fluctuations may lead to attraction between oxygen holes. As in weak-coupling theory, we find (i) favorable tendencies towards second-nearest-neighbor s- and d-wave filling, with larger doping favoring d-wave symmetry; (ii) a nonmonotonic dependence of the pairing tendencies upon the on-site quadrupole level splitting; and (iii) a strong suppression of all nearest-neighbor pairing.

Jarrell, M.; Cox, D. L.

1990-11-01

102

Quadrupolar spin relaxation due to electric field gradients induced by vibrations and collisions  

Microsoft Academic Search

The spin relaxation of quadrupolar nuclei in highly symmetric electronic environments via vibrationally-induced electric field gradients is considered. A model is presented for tetrahedral molecules which yields a nuclear quadrupole coupling constant for 189Os in an excited vibrational state of OsO4 which is in reasonable agreement with experimentally observed values. The nuclear quadrupole coupling constants for the central nucleus in

H. Jörg Osten; Cynthia J. Jameson

1986-01-01

103

Quadrupolar spin relaxation due to electric field gradients induced by vibrations and collisions  

Microsoft Academic Search

The spin relaxation of quadrupolar nuclei in highly symmetric electronic environments via vibrationally-induced electric field gradients is considered. A model is presented for tetrahedral molecules which yields a nuclear quadrupole coupling constant for Os in an excited vibrational state of OsO4 which is in reasonable agreement with experimentally observed values. The nuclear quadrupole coupling constants for the central nucleus in

H. Jörg Osten; Cynthia J. Jameson

1986-01-01

104

High-Resolution NMR of Quadrupolar Nuclei in the Solid State  

SciTech Connect

This dissertation describes recent developments in solid state nuclear magnetic resonance (NMR), for the most part involving the use of dynamic-angle spinning (DAS) NMR to study quadrupolar nuclei. Chapter 1 introduces some of the basic concepts and theory that will be referred to in later chapters, such as the density operator, product operators, rotations, coherence transfer pathways, phase cycling, and the various nuclear spin interactions, including the quadrupolar interaction. Chapter 2 describes the theory behind motional averaging experiments, including DAS, which is a technique where a sample is spun sequentially about two axis oriented at different angles with respect to the external magnetic field such that the chemical shift and quadrupolar anisotropy are averaged to zero. Work done on various rubidium-87 salts is presented as a demonstration of DAS. Chapter 3 explains how to remove sidebands from DAS and magic-angle spinning (MAS) experiments, which result from the time-dependence of the Hamiltonian under sample spinning conditions, using rotor-synchronized {pi}-pulses. Data from these experiments, known as DAH-180 and MAH-180, respectively, are presented for both rubidium and lead salts. In addition, the applicability of this technique to double rotation (DOR) experiments is discussed. Chapter 4 concerns the addition of cross-polarization to DAS (CPDAS). The theory behind spin locking and cross polarizing quadrupolar nuclei is explained and a method of avoiding the resulting problems by performing cross polarization at 0{sup o} (parallel) with respect to the magnetic field is presented. Experimental results are shown for a sodium-23 compound, sodium pyruvate, and for oxygen-17 labeled L-akmine. In Chapter 5, a method for broadening the Hartmann-Hahn matching condition under MAS, called variable effective field cross-polarization (VEFCI?), is presented, along with experimental work on adamantane and polycarbonate.

Gann, Sheryl Lee

1995-11-30

105

Possible quadrupolar ordering in a Kondo-lattice compound Ce3Pd20Ge6  

Microsoft Academic Search

Magnetic and transport properties of the cubic ternary compound Ce3Pd20Ge6 are herein reported. The electrical resistivity exhibits the Kondo lattice behavior and a large T2 coefficient at low temperatures, indicating that this compound is a heavy-electron system with a Kondo temperature of a few degrees Kelvin. The low-temperature specific heat revealed two successive anomalies at T1=1.2 K and T2=0.7 K.

Jiro Kitagawa; Naoya Takeda; Masayasu Ishikawa

1996-01-01

106

Structure evolution and entropy change of temperature and magnetic field induced magneto-structural transition in Mn1.1Fe0.9P0.76Ge0.24  

NASA Astrophysics Data System (ADS)

The compound Mn1.1Fe0.9P0.76Ge0.24 has been studied using neutron powder diffraction (NPD), differential scanning calorimeter (DSC), and magnetic measurements, in order to clarify the nature of the magnetic and structural transition and measure the associated entropy change (?S). The strongly first order transition occurs from a paramagnetic (PM) to a ferromagnetic (FM) phase and can be induced either by temperature or by an applied magnetic field. Our investigations indicate that the two processes exhibit identical evolutions regarding the crystal and magnetic structures, indicating they should have the same entropy change. We, therefore, conclude that the ?SDSC obtained by the DSC method (where the transition is temperature induced) is valid also for the magnetically induced transition, thus avoiding uncertainties connected with the magnetic measurements. We have obtained the ?SDSC = 33.8 J/kg . K for this sample upon cooling, which would increase to 42.7 J/kg . K for a impurity-free and completely homogeneous sample. For comparison, the magnetic entropy changes (?SM) induced by magnetic field and calculated using the Maxwell relation yields a ?SM = 46.5J/kg . K, 38% higher than ?SDSC. These entropy results are compared and discussed.

Yue, Ming; Liu, Danmin; Huang, Qingzhen; Wang, Tong; Hu, Fengxia; Li, Jingbo; Rao, Guanghui; Shen, Baogen; Lynn, Jeffery W.; Zhang, Jiuxing

2013-01-01

107

Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects  

SciTech Connect

Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I = 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an encoding module for the recently developed NMR remote detection experiment. The feasibility of using hyperpolarized xenon-129 gas as a sensor is discussed. This work also reports the use of an optical atomic magnetometer to detect the nuclear magnetization of Xe-129 gas, which has potential applicability as a detection module for NMR remote detection experiments.

Urban, Jeffry Todd

2004-12-21

108

Orbital-Ordering-Driven Multiferroicity and Magnetoelectric Coupling in GeV4S8  

NASA Astrophysics Data System (ADS)

We report here the discovery of multiferroicity and large magnetoelectric coupling in the type I orbital order system GeV4S8. Our study demonstrates that this clustered compound displays a para-ferroelectric transition at 32 K. This transition originates from an orbital ordering which reorganizes the charge within the transition metal clusters. Below the antiferromagnetic transition at 17 K, the application of a magnetic field significantly affects the ferroelectric polarization, revealing thus a large magnetoelectric coupling. Our study suggests that the application of a magnetic field induces a metamagnetic transition which significantly affects the ferroelectric polarization thanks to an exchange striction phenomenon.

Singh, Kiran; Simon, Charles; Cannuccia, Elena; Lepetit, Marie-Bernadette; Corraze, Benoit; Janod, Etienne; Cario, Laurent

2014-09-01

109

Bulk and interfacial properties of a dipolar-quadrupolar fluid in a uniform electric field: a density-functional approach.  

PubMed

We have studied the bulk and interfacial properties of a dipolar-quadrupolar fluid based on an extended modified mean-field density-functional theory. Effects of a uniform electric field on the bulk and interfacial properties are also studied. Results of the coexisting vapor-liquid densities, interfacial profiles of the density and orientation order parameters, the surface tension, and their dependence on the temperature, magnitude of molecule dipole and quadrupole moment, and the applied field are obtained. In general, we find that the applied field increases the critical temperature, broadens the vapor-liquid coexistence curves, and reduces the surface tension. We also find that if the quadrupole moment is positive, the reduction in the surface tension is greater when the applied field is in the direction from the vapor to the liquid phase than the reduction when the field is in the opposite direction. This apparent symmetry breaking by reversing the field direction may offer a molecular mechanism to explain the phenomenon of the sign preference in liquid droplet formation on charged condensation centers. PMID:12935128

Warshavsky, V B; Zeng, X C

2003-07-01

110

On magnetic-field-induced dissipationless electric current in nanowires  

E-print Network

We propose a general design of a metallic double-nanowire structure which may support an equilibrium dissipationless electric current in the presence of magnetic field. The structure consists of a compact wire element of a specific shape, which is periodically extended in one spatial dimension. Topologically, each wire element is equivalent to a ring, which supports a dissipationless current in the presence of magnetic flux similarly to the persistent electric current in a normal metal nanoring. Geometrically, each wire element breaks spatial inversion symmetry so that the equilibrium electric current through the device becomes nonzero. We also argue that the same effect should exist in long planar chiral nanoribbons subjected to external magnetic field.

M. N. Chernodub

2013-03-28

111

Magnetic-field-induced kinetics of ferroelectric phase transitions  

NASA Astrophysics Data System (ADS)

The dynamics of ferroelectric interphase boundaries is studied in external magnetic fields. On the basis of the exact solution of the time-dependent Ginzburg-Landau equation the velocity of the interphase boundary and its width are calculated as functions of the applied magnetic field.

Gordon, A.; Wyder, P.

1992-09-01

112

Magnetic field induced differential neutron phase contrast imaging  

SciTech Connect

Besides the attenuation of a neutron beam penetrating an object, induced phase changes have been utilized to provide contrast in neutron and x-ray imaging. In analogy to differential phase contrast imaging of bulk samples, the refraction of neutrons by magnetic fields yields image contrast. Here, it will be reported how double crystal setups can provide quantitative tomographic images of magnetic fields. The use of magnetic air prisms adequate to split the neutron spin states enables a distinction of field induced phase shifts and these introduced by interaction with matter.

Strobl, M.; Treimer, W.; Walter, P.; Keil, S.; Manke, I. [Department of Physical Chemistry, Ruprecht Karls University Heidelberg, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany and Hahn-Meitner Institute Berlin, SF1, Glienickerstr. 100, 14109 Berlin (Germany); Hahn-Meitner Institute Berlin, Glienickerstr. 100, 14109 Berlin, Germany and University of Applied Sciences (TFH) Berlin, Luxemburger Str. 10, 13353 Berlin (Germany); Hahn-Meitner Institute Berlin, Glienickerstr. 100, 14109 Berlin (Germany)

2007-12-17

113

Strong Magnetic Field Induced Changes of Gene Expression in Arabidopsis  

NASA Astrophysics Data System (ADS)

We review our studies of the biological impact of magnetic field strengths of up to 30 T on transgenic arabidopsis plants engineered with a stress response gene consisting of the alcohol dehydrogenase (Adh) gene promoter driving the ?-glucuronidase (GUS) gene reporter. Field strengths in excess of 15 T induce expression of the Adh/GUS transgene in the roots and leaves. Microarray analyses indicate that such field strengths have a far reaching effect on the genome. Wide spread induction of stress-related genes and transcription factors, and a depression of genes associated with cell wall metabolism are prominent examples.

Paul, A.-L.; Ferl, R. J.; Klingenberg, B.; Brooks, J. S.; Morgan, A. N.; Yowtak, J.; Meisel, M. W.

2005-07-01

114

Magnetic-field-induced antiferromagnetism in the Kondo lattice  

E-print Network

The half-filled Kondo lattice model, augmented by a Zeeman term, serves as a useful model of a Kondo insulator in an applied magnetic field. A variational mean field analysis of this system on a square lattice, backed up ...

Beach, Kevin S. D. (Kevin Stuart David), 1975-

2004-01-01

115

A Conduction Cooled High Temperature Superconductor Quadrupolar Superferric Magnet, Design and Construction  

NASA Astrophysics Data System (ADS)

The paper presents the prototype of an YBCO superferric quadrupolar magnet for high gradient magnetic field generation, design and construction. The temperature of the superconducting coil has to be kept within safe limits or the HTS would exit the superconductive state. Of particular concern is the "warm" beam tube that passes through the magnet. Cryogenic conduction cooling with a closed cycle G-M Cooler may ensure the removal of the ambient heat influx. Numerical simulation results on the magnetic field and heat transfer problems are then discussed. The computational domain is abstracted out of the CAD design of the system. The design solution is presented and compared with the numerical simulations results.

Dobrin, I.; Morega, A. M.; Nedelcu, A.; Morega, M.; Neamtu, J.

2014-05-01

116

Directed Transformation from Quadrupolar to Dipolar Nematic Colloids by an In-Plane Electric Field  

NASA Astrophysics Data System (ADS)

We demonstrate direction-controlled transformation from quadrupolar to dipolar nematic colloids using an in-plane electric field. When the electric field is applied in the direction perpendicular to the rubbing direction, a splay-bend wall is induced, which traps colloidal particles. Above the applied electric field of 0.14 V/µm, a Saturn-ring defect shrinks into a hedgehog defect due to the symmetric reorientation of the liquid crystal molecules around the particle. The direction of the shrinking is determined by the pretilt angle of the liquid crystal and the field direction near the edge of the electrode.

Tagashira, Kenji; Asakura, Keita; Yoshida, Hiroyuki; Ozaki, Masanori

2013-02-01

117

Dynamic Effects on the Powder Line Shapes of Half-Integer Quadrupolar Nuclei: A Solid-State NMR Study of XO4  

E-print Network

Dynamic Effects on the Powder Line Shapes of Half-Integer Quadrupolar Nuclei: A Solid-State NMR, Chicago, Illinois 60607 ReceiVed: August 6, 2001 Multinuclear solid-state nuclear magnetic resonance interest in the solid- state NMR of half-integer quadrupolar nuclei.8-13 This is partly due

Frydman, Lucio

118

Quadrupolar nuclear magnetic resonance spectroscopy in solids using frequency-swept echoing pulses.  

PubMed

The acquisition of ideal powder line shapes remains a recurring challenge in solid-state wideline nuclear magnetic resonance (NMR). Certain species, particularly quadrupolar spins in sites associated with large electric field gradients, are difficult to excite uniformly and with good efficiencies. This paper discusses some of the opportunities that arise upon departing from standard spin-echo excitation approaches and switching to echo sequences that use low-power, frequency-swept radio frequency (rf) pulses instead. The reduced powers demanded by such swept rf fields allow one to excite spins in different crystallites efficiently and with orientation-independent pulse angles, while the large bandwidths of interest that are needed by the measurement can be covered, thanks to the use of broadband frequency sweeps. The fact that the spins' evolution and ensuing dephasing starts at the beginning of such rf manipulation calls for the use of spin-echo sequences; a number of alternatives capable of providing the desired line shapes both in the frequency and in the time domains are introduced and experimentally demonstrated. Sensitivity- and lineshape-wise these experiments are competitive vis-a-vis current implementations of wideline quadrupolar NMR based on hard rf pulses; additional opportunities that may derive from these ideas are also briefly discussed. PMID:18035888

Bhattacharyya, Rangeet; Frydman, Lucio

2007-11-21

119

A NON-RADIAL ERUPTION IN A QUADRUPOLAR MAGNETIC CONFIGURATION WITH A CORONAL NULL  

SciTech Connect

We report one of the several homologous non-radial eruptions from NOAA active region (AR) 11158 that are strongly modulated by the local magnetic field as observed with the Solar Dynamic Observatory. A small bipole emerged in the sunspot complex and subsequently created a quadrupolar flux system. Nonlinear force-free field extrapolation from vector magnetograms reveals its energetic nature: the fast-shearing bipole accumulated {approx}2 Multiplication-Sign 10{sup 31} erg free energy (10% of AR total) over just one day despite its relatively small magnetic flux (5% of AR total). During the eruption, the ejected plasma followed a highly inclined trajectory, over 60 Degree-Sign with respect to the radial direction, forming a jet-like, inverted-Y-shaped structure in its wake. Field extrapolation suggests complicated magnetic connectivity with a coronal null point, which is favorable of reconnection between different flux components in the quadrupolar system. Indeed, multiple pairs of flare ribbons brightened simultaneously, and coronal reconnection signatures appeared near the inferred null. Part of the magnetic setting resembles that of a blowout-type jet; the observed inverted-Y structure likely outlines the open field lines along the separatrix surface. Owing to the asymmetrical photospheric flux distribution, the confining magnetic pressure decreases much faster horizontally than upward. This special field geometry likely guided the non-radial eruption during its initial stage.

Sun Xudong; Hoeksema, J. Todd; Liu Yang; Hayashi, Keiji [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States); Chen Qingrong, E-mail: xudong@sun.stanford.edu [Department of Physics, Stanford University, Stanford, CA 94305 (United States)

2012-10-01

120

Alkaline earth chloride hydrates: chlorine quadrupolar and chemical shift tensors by solid-state NMR spectroscopy and plane wave pseudopotential calculations.  

PubMed

A series of alkaline earth chloride hydrates has been studied by solid-state (35/37)Cl NMR spectroscopy in order to characterize the chlorine electric field gradient (EFG) and chemical shift (CS) tensors and to relate these observables to the structure around the chloride ions. Chlorine-35/37 NMR spectra of solid powdered samples of pseudopolymorphs (hydrates) of magnesium chloride (MgCl(2).6H(2)O), calcium chloride (CaCl(2).2H(2)O), strontium chloride (SrCl(2), SrCl(2).2H(2)O, and SrCl(2).6H(2)O), and barium chloride (BaCl(2).2H(2)O) have been acquired under stationary and magic-angle spinning conditions in magnetic fields of 11.75 and 21.1 T. Powder X-ray diffraction was used as an additional tool to confirm the purity and identity of the samples. Chlorine-35 quadrupolar coupling constants (C(Q)) range from essentially zero in cubic anhydrous SrCl(2) to 4.26+/-0.03 MHz in calcium chloride dihydrate. CS tensor spans, Omega, are between 40 and 72 ppm, for example, Omega= 45+/-20 ppm for SrCl(2).6H(2)O. Plane wave-pseudopotential density functional theory, as implemented in the CASTEP program, was employed to model the extended solid lattices of these materials for the calculation of their chlorine EFG and nuclear magnetic shielding tensors, and allowed for the assignment of the two-site chlorine NMR spectra of barium chloride dihydrate. This work builds upon our current understanding of the relationship between chlorine NMR interaction tensors and the local molecular and electronic structure, and highlights the particular sensitivity of quadrupolar nucleus solid-state NMR spectroscopy to the differences between various pseudopolymorphic structures in the case of strontium chloride. PMID:17385204

Bryce, David L; Bultz, Elijah B

2007-01-01

121

Separate-Local-Field NMR Spectroscopy on Half-Integer Quadrupolar Nuclei Julia Grinshtein, Christopher V. Grant, and Lucio Frydman*  

E-print Network

anisotropy affecting these species generally restricts their solid-state NMR study to central field of high- resolution spin-1/2 solid-state NMR. Then, separate-local-field (SLF) MAS techniques such SLF measurements to solid-state quadrupolar NMR. Two main differences arise upon invoking SLF MAS

Frydman, Lucio

122

Complete description of the interactions of a quadrupolar nucleus with a radiofrequency field. Implications for data fitting.  

PubMed

We present a theory, with experimental tests, that treats exactly the effect of radiofrequency (RF) fields on quadrupolar nuclei, yet retains the symbolic expressions as much as possible. This provides a mathematical model of these interactions that can be easily connected to state-of-the-art optimization methods, so that chemically-important parameters can be extracted from fits to experimental data. Nuclei with spins >1/2 typically experience a Zeeman interaction with the (possibly anisotropic) local static field, a quadrupole interaction and are manipulated with RF fields. Since RF fields are limited by hardware, they seldom dominate the other interactions of these nuclei and so the spectra show unusual dependence on the pulse width used. The theory is tested with (23)Na NMR nutation spectra of a single crystal of sodium nitrate, in which the RF is comparable with the quadrupole coupling and is not necessarily on resonance with any of the transitions. Both the intensity and phase of all three transitions are followed as a function of flip angle. This provides a more rigorous trial than a powder sample where many of the details are averaged out. The formalism is based on a symbolic approach which encompasses all the published results, yet is easily implemented numerically, since no explicit spin operators or their commutators are needed. The classic perturbation results are also easily derived. There are no restrictions or assumptions on the spin of the nucleus or the relative sizes of the interactions, so the results are completely general, going beyond the standard first-order treatments in the literature. PMID:23611427

Spencer, T Leigh; Goward, Gillian R; Bain, Alex D

2013-06-01

123

The Powering Source and Origin of the Quadrupolar Molecular Outflow in L723  

NASA Astrophysics Data System (ADS)

We present the results of single-dish observations of CS J = 2-1 and J = 3-2 and interferometric observations of CO J = 1-0 toward the center of the quadrupolar molecular outflow in L723. We have detected a compact CS condensation having a size of 0.04 pc and a mass of 0.55 M? toward the northeastern radio continuum source VLA 2 (AER91 2). The CO outflow also shows the distribution centered at VLA 2. These results suggest that the source VLA 2 is the young stellar object that is powering the conspicuous molecular outflow system. On the other hand, there is no enhancement in the CS intensity or the CO outflow distribution toward the southwestern radio continuum source VLA 1 (AER91 1), indicating that the source VLA 1 does not contribute to the morphology of the quadrupolar outflow in L723. The CO distribution observed with the interferometer delineates the western edge of the blue lobe and the northeastern edge of the red lobe revealed in the single-dish map, suggesting that the outflow in L723 is a single bipolar outflow with a wide opening angle of 120°-170° rather than two independent outflows. We found signs of interaction between the blueshifted outflow and the dense ambient gas: (1) there is a compact CS clump blueshifted by ~1 km s-1, the distribution of which shows anticorrelation with the blueshifted CO outflow; (2) both CS and NH3 spectra show the line broadening toward the blueshifted clump; and (3) there is a temperature enhancement at the boundary of the blueshifted clump of CS emission. It is likely that such interaction with the dense ambient gas has the increased opening angle of the outflow, which accounts for the quadrupolar morphology. Based on observations made at Nobeyama Radio Observatory (NRO). The Nobeyama Radio Observatory is a branch of the National Astronomical Observatory, an interuniversity research institute operated by the Ministry of Education, Science, Sport, and Culture, Japan.

Hirano, Naomi; Hayashi, Saeko S.; Umemoto, Tomofumi; Ukita, Nobuharu

1998-09-01

124

From bipolar to quadrupolar - The collimation processes of the Cepheus A outflow  

NASA Technical Reports Server (NTRS)

Results of new K-band observations of the (1, 1) and (2, 2) ammonia lines toward Cepheus A are reported. The lines are mapped with approximately 2 arcsec of angular resolution and 0.3 km/s of velocity resolution. A sensitivity of 10 mJy has been achieved. The observations reveal details of the spatial and kinematics structure of the ambient high-density gas. It is suggested that the interstellar high-density gas is diverting and redirecting the outflow in the sense that the quadrupolar structure of the molecular outflow is produced by the interaction with the ammonia condensationss, with Cep A-1 and Cep A-3 splitting in two halves, respectively the blue- and redshifted lobes of an east-west bipolar molecular outflow.

Torrelles, Jose M.; Verdes-Montenegro, Lourdes; Ho, Paul T. P.; Rodriguez, Luis F.; Canto, Jorge

1993-01-01

125

Probing proximities between different quadrupolar isotopes using multi-pulse cross-polarization  

NASA Astrophysics Data System (ADS)

We present a novel cross-polarization MAS NMR pulse sequence to probe proximities between half-integer quadrupolar isotopes. This sequence employs a multi-pulse cross-polarization (MP-CP) transfer, instead of the previous continuous-wave CP (CW-CP) transfer. With respect to CW-CP transfers, our sequence is more robust with respect to offsets and Rotary Resonance Recoupling detrimental effects, especially when taking into account rf-inhomogeneity. Moreover, by using a frequency splitter and a single channel MAS probe, this MP-CP sequence may allow analyzing the through-space connectivities between two isotopes with half-integer spin values and close Larmor frequencies.

Lu, Xingyu; Tankamony, Aany Sofia Lilly; Trébosc, Julien; Lafon, Olivier; Amoureux, Jean-Paul

2013-03-01

126

Bis-pyridinium quadrupolar derivatives. High Stokes shift selective probes for bio-imaging  

NASA Astrophysics Data System (ADS)

We describe the design, synthesis and characterization of five high Stokes shift quadrupolar heteroaryl compounds suitable as fluorescent probes in bio-imaging. In particular, we characterize the photophysical properties and the intracellular localization in Human Umbilical Vein Endothelial Cells (HUVEC) and Human Mesenchymal Stem Cells (HMSCs) for each dye. We show that, amongst all of the investigated derivatives, the 2,5-bis[1-(4-N-methylpyridinium)ethen-2-yl)]- N-methylpyrrole salt is the best candidates as selective mitochondrial tracker. Finally, we recorded the full emission spectrum of the most performing - exclusively mitochondrial selective - fluorescent probe directly from HUVEC stained cells. The emission spectrum collected from the stained mitochondria shows a remarkably more pronounced vibronic structure with respect to the emission of the free fluorophore in solution.

Salice, Patrizio; Versari, Silvia; Bradamante, Silvia; Meinardi, Francesco; Macchi, Giorgio; Pagani, Giorgio A.; Beverina, Luca

2013-11-01

127

Pulmonary MRI contrast using Surface Quadrupolar Relaxation (SQUARE) of hyperpolarized 83Kr?  

PubMed Central

Hyperpolarized 83Kr has previously been demonstrated to enable MRI contrast that is sensitive to the chemical composition of the surface in a porous model system. Methodological advances have lead to a substantial increase in the 83Kr hyperpolarization and the resulting signal intensity. Using the improved methodology for spin exchange optical pumping of isotopically enriched 83Kr, internal anatomical details of ex vivo rodent lung were resolved with hyperpolarized 83Kr MRI after krypton inhalation. Different 83Kr relaxation times were found between the main bronchi and the parenchymal regions in ex vivo rat lungs. The T1 weighted hyperpolarized 83Kr MRI provided a first demonstration of surface quadrupolar relaxation (SQUARE) pulmonary MRI contrast. PMID:24144493

Six, Joseph S.; Hughes-Riley, Theodore; Lilburn, David M.L.; Dorkes, Alan C.; Stupic, Karl F.; Shaw, Dominick E.; Morris, Peter G.; Hall, Ian P.; Pavlovskaya, Galina E.; Meersmann, Thomas

2014-01-01

128

Method to determine the optimal layer number for the quadrupolar fiber coil  

NASA Astrophysics Data System (ADS)

For a high precision interferometric fiber optic gyroscope (IFOG) under temperature control, a short start-up time and small temperature drift are important for its applications. The start-up time and the temperature drift of IFOG with the same fiber length but with a different fiber coil layer number are investigated and compared. Simulation by finite difference time domain method is done to illustrate the existence of optimal layer number for the fiber coil wound by the quadrupolar method. Theoretical analysis is then provided and a closed-form formulation is given to calculate the optimal layer number of the fiber coil, which can effectively reduce both the start-up time and temperature drift of IFOG. Our study is meaningful in improving the thermal performance of the fiber coil.

Gao, Zhongxing; Zhang, Yonggang; Gao, Wei

2014-08-01

129

Rotor-encoded heteronuclear MQ MAS NMR spectroscopy of half-integer quadrupolar and spin I=1/2 nuclei.  

PubMed

A new two-dimensional heteronuclear multiple-quantum magic-angle spinning (MQ MAS) experiment is presented which combines high resolution for the half-integer quadrupolar nucleus with information about the dipolar coupling between the quadrupolar nucleus and a spin I=1/2 nucleus. Homonuclear MQ coherence is initially created for the half-integer quadrupolar nucleus by a single pulse as in a standard MQ MAS experiment. REDOR recoupling of the heteronuclear dipolar coupling then allows the creation of a heteronuclear multiple-quantum coherence comprising multiple- and single-quantum coherence of the quadrupolar and spin I=1/2 nucleus, respectively, which evolves during t1. Provided that the t1 increment is not rotor synchronized, rotor-encoded spinning-sideband patterns are observed in the indirect dimension. Simulated spectra for an isolated IS spin pair show that these patterns depend on the recoupling time, the magnitude of the dipolar coupling, the quadrupolar parameters, as well as the relative orientation of the quadrupolar and dipolar principal axes systems. Spectra are presented for Na2HPO4, with the heteronuclear 23Na-1HMQ MAS experiments beginning with the excitation of 23Na (spin I=3/2) three-quantum coherence. Coherence counting experiments demonstrate that four- and two-quantum coherences evolve during t1. The heteronuclear spinning-sideband patterns observed for the three-spin H-Na-H system associated with the Na(2) site are analyzed. For an IS2 system, simulated spectra show that, considering the free parameters, the spinning-sideband patterns are particularly sensitive to only, first, the angle between the two IS internuclear vectors and, second, the two heteronuclear dipolar couplings. It is demonstrated that the proton localization around the Na(2) site according to the literature crystal structure of Na2HPO4 is erroneous. Instead, the experimental data is consistent with two alternative different structural arrangements, whereby either there is a deviation of 10 degrees from linearity for the case of two identical Na-H distances, or there is a linear arrangement, but the two Na-H distances are different. Furthermore, the question of the origin of spinning-sidebands in the (homonuclear) MQ MAS experiment is revisited. It is shown that the asymmetric experimental MQ sideband pattern observed for the low-C(Q) Na(2) site in Na(2)HPO4 can only be explained by considering the 23Na chemical shift anisotropy. PMID:11820831

Lupulescu, Adonis; Brown, Steven P; Spiess, Hans Wolfgang

2002-01-01

130

The "Príncipes de Asturias" nebula: a new quadrupolar planetary nebula from the IPHAS survey  

NASA Astrophysics Data System (ADS)

Context: .The Isaac Newton Telescope Photometric H? Survey (IPHAS) is currently mapping the Northern Galactic plane reaching to r'=20 mag with typically 1primeprime resolution. Hundreds of Planetary Nebulae (PNe), both point-like and resolved, are expected to be discovered. We report on the discovery of the first new PN from this survey: it is an unusual object located at a large galactocentric distance and has a very low oxygen abundance. Aims: .Detecting and studying new PNe will lead to improved estimates of the population size, binary fraction and lifetimes, and yield new insights into the chemistry of the interstellar medium at large galactocentric distances. Methods: .Compact nebulae are searched for in the IPHAS photometric catalogue, selecting those candidates with a strong H? excess in the r'-H? vs. r'-i' colour-colour diagram. Searches for extended nebulae are by visual inspection of the mosaics of continuum-subtracted H? images at a spatial sampling of 5×5 arcsec^2. Follow-up spectroscopy enables confirmation of the PNe, and their physico-chemical study. Results: .The first planetary nebula discovered via IPHAS imagery shows an intricate morphology: there is an inner ring surrounding the central star, bright inner lobes with an enhanced waist, and very faint lobular extensions reaching up to more than 100''. We classify it as a quadrupolar PN, a rather unusual class of planetary showing two pairs of misaligned lobes. From long-slit spectroscopy we derive T_e[ Nii] =12 800±1000 K, Ne = 390±40 cm-3, and chemical abundances typical of Peimbert's type I nebulae (He/H =0.13, N/O =1.8) with an oxygen abundance of 12+log(O/H)=8.17±0.15. A kinematic distance of 7.0+4.5-3.0 kpc is derived, implying an unusually large size of >4 pc for the nebula. The photometry of the central star indicates the presence of a relatively cool companion. This, and the evidence for a dense circumstellar disk and quadrupolar morphology, all of which are rare among PNe, support the hypothesis that this morphology is related to binary interaction.

Mampaso, A.; Corradi, R. L. M.; Viironen, K.; Leisy, P.; Greimel, R.; Drew, J. E.; Barlow, M. J.; Frew, D. J.; Irwin, J.; Morris, R. A. H.; Parker, Q. A.; Phillipps, S.; Rodríguez-Flores, E. R.; Zijlstra, A. A.

2006-10-01

131

Magnetic alignment and quadrupolar/paramagnetic cross-correlation in complexes of Na with LnDOTP5-.  

PubMed

The observation of a double-quantum filtered signal of quadrupolar nuclei (e.g. (23)Na) in solution has been traditionally interpreted as a sign for anisotropic reorientational motion. Ling and Jerschow (2007) have found that a (23)Na double-quantum signal is observed also in solutions of TmDOTPNa(5). Interference effects between the quadrupolar and the paramagnetic interactions have been reported to lead to the appearance of double-quantum coherences even in the absence of a residual quadrupolar interaction. In addition, such processes lead to differential linebroadening effects between the satellite transitions, akin to effects that are well known for dipolar-CSA cross-correlation. Here, we report experiments on sodium in the presence of LnDOTP compounds, where it is shown that these cross-correlation effects correlate well with the pseudo-contact shift. In addition, anisotropic g-values of the lanthanide compounds in question, can also lead to alignment within the magnetic field, and consequently to the appearance of line splitting and double-quantum coherences. The two competing effects are demonstrated and it is concluded that both cross-correlated relaxation and alignment in the magnetic field must be at work in the systems described here. PMID:22342118

Eliav, Uzi; Shekar, S Chandra; Ling, Wen; Navon, Gil; Jerschow, Alexej

2012-03-01

132

Effective shell model Hamiltonians from density functional theory: Quadrupolar and pairing correlations  

NASA Astrophysics Data System (ADS)

We describe a procedure for mapping a self-consistent mean-field theory (also known as density functional theory) onto a shell-model Hamiltonian that includes quadrupole-quadrupole and monopole pairing interactions in a truncated space. We test our method in the deformed N=Zsd-shell nuclei Ne20, Mg24, and Ar36, starting from the Hartree-Fock plus Bardeen-Cooper-Schrieffer (BCS) approximation of the universal sd shell-model interaction. A similar method is then followed using the SLy4 Skyrme energy density functional in the particle-hole channel plus a zero-range density-dependent force in the pairing channel. Based on the ground-state solution of this density functional theory at the Hartree-Fock plus BCS level, an effective shell-model Hamiltonian is constructed. We apply this mapped Hamiltonian to extract quadrupolar and pairing correlation energies beyond the mean-field approximation. The rescaling of the mass quadrupole operator in the truncated shell-model space is found to be almost independent of the coupling strength used in the pairing channel of the underlying mean-field theory.

Rodríguez-Guzmán, R.; Alhassid, Y.; Bertsch, G. F.

2008-06-01

133

The influence of sigma and pi acceptors on two-photon absorption and solvatochromism of dipolar and quadrupolar unsaturated organic compounds.  

PubMed

Two-photon absorption cross sections delta and solvatochromic properties were determined for a series of quadrupolar and dipolar compounds by using femtosecond excitation in the spectral range between 710 and 960 nm. The compounds investigated were distyrylbenzenes and polyenes bearing appropriate pi or sigma acceptors. The delta values for the centrosymmetric compounds trans, trans- 1,4-bis[2-(2',5'-dihexyloxy)phenylethenyl]-2,3,5,6-tetrafluorobenzene (6), trans, trans-1,4-bis[2-(4'-dibutylamino)phenylethenyl]- 2,3,5,6-tetrafluorobenzene (2), trans, trans-1,4-bis[2-(4'dimethylamino)phenylbutadienyl]- 2,3,5,6-tetrafluorobenzene (7), trans,-trans-1,4-bis[2-(4'-dimethylamino)phenylethenyl]2,5- dicyanobenzene (4) and trans,trans-1,4-bis[2-(4'-dimethylamino)phenylethenyl]-2- propylsulfonyl-5-(2-ethylhexyl)sulfonylbenzene (3) are on the order of 600, 1400, 1700, 3000, and 4100 x 10(-50) cm4 s photon-1, respectively. The corresponding dipolar compounds trans-2-(4'- dimethylaminophenyl)ethenyl-2,3,4,5,6-pentafluorobene (8), trans-4-(4'-dimethylaminophenyl)butadienyl-2,3,4,5,6-pentafluorobenzene (9), trans-6-(4'-dimethylaminophenyl)hexatrienyl-2,3,4,5,6- pentafluorobenzene (10) were additionally investigated. All centrosymmtric compounds are good fluorescent materials, while the dipolar chromophores 8-10 exhibit low fluorescence quantum yields. Solvatochromism was also observed for the fluorophores 2-10 as a result of intramolecular charge transfer (ICT). Furthermore, a reasonable correlation was obtained between measured and calculated delta. Quantum chemical calculations were performed by using the INDO Hamiltonian with a MRDCI scheme. The results show that the sum over states (SOS) expression for the second hyperpolarizability gamma is appropriate to describe the mechanism of two-photon absorption. Mechanistic investigations of quadrupolar compounds showed that the energy of the two-photon excited state is higher than S1. PMID:12674597

Strehmel, Bernd; Sarker, Ananda M; Detert, Heiner

2003-03-17

134

Formation of a White-Light Jet Within a Quadrupolar Magnetic Configuration  

NASA Astrophysics Data System (ADS)

We analyze multi-wavelength and multi-viewpoint observations of a large-scale event viewed on 7 April 2011, originating from an active-region complex. The activity leads to a white-light jet being formed in the outer corona. The topology and evolution of the coronal structures were imaged in high resolution using the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). In addition, large field-of-view images of the corona were obtained using the Sun Watcher using Active Pixel System detector and Image Processing (SWAP) telescope onboard the PRoject for Onboard Autonomy (PROBA2) microsatellite, providing evidence for the connectivity of the coronal structures with outer coronal features that were imaged with the Large Angle Spectrometric Coronagraph (LASCO) C2 on the S olar and Heliospheric Observatory (SOHO). The data sets reveal an Eiffel-tower type jet configuration extending into a narrow jet in the outer corona. The event starts from the growth of a dark area in the central part of the structure. The darkening was also observed in projection on the disk by the Solar TErrestrial RElations Observatory-Ahead (STEREO-A) spacecraft from a different point of view. We assume that the dark volume in the corona descends from a coronal cavity of a flux rope that moved up higher in the corona but still failed to erupt. The quadrupolar magnetic configuration corresponds to a saddle-like shape of the dark volume and provides a possibility for the plasma to escape along the open field lines into the outer corona, forming the white-light jet.

Filippov, Boris; Koutchmy, Serge; Tavabi, Ehsan

2013-08-01

135

Magnetic order-order phase transitions in magnets with collective electrons: MnCoSi  

NASA Astrophysics Data System (ADS)

First principles calculations of the electronic structure of MnCoSi and a spiral state model are used to analyze magnetic-field induced magnetic order-order phase transitions in MnCoSi at pressures up to 2kbar. This shows that the magnetic moments of Mn and Co in MnCoSi are created by collective d-electrons and that pressure stimulation of induced order-order transitions in this material can be a consequence of structural changes in the density of d-electron states as the pressure is raised. Induced order-order transitions are described by a single-band model for the spiral state in which the band filling and the nonmagnetic density of electron states are based on first principles calculations of the electronic structure of MnCoSi. This model shows that the low-temperature states induced by a magnetic field are not collinear ferromagnetic structures, but may represent the coexistence of a homogeneous ferromagnetic component and a periodic spiral component of the total magnetic moment of the d-band. A pure ferromagnetic state at low temperatures can be regarded as metastable.

Valkov, V. I.; Golovchan, A. V.; Dvornikov, E. A.; Todris, B. M.

2010-12-01

136

Using the dipolar and quadrupolar moments to improve solar-cycle predictions based on the polar magnetic fields.  

PubMed

The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and Earth's upper atmosphere (commonly referred to as space weather and climate). In recent years there has been an effort to develop accurate solar cycle predictions, leading to nearly a hundred widely spread predictions for the amplitude of solar cycle 24. Here we show that cycle predictions can be made more accurate if performed separately for each hemisphere, taking advantage of information about both the dipolar and quadrupolar moments of the solar magnetic field during minimum. PMID:23931351

Muñoz-Jaramillo, Andrés; Balmaceda, Laura A; DeLuca, Edward E

2013-07-26

137

Using the Dipolar and Quadrupolar Moments to Improve Solar-Cycle Predictions Based on the Polar Magnetic Fields  

E-print Network

The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and Earth's upper atmosphere (commonly referred to as space weather and climate). In recent years there has been an effort to develop accurate solar cycle predictions, leading to nearly a hundred widely spread predictions for the amplitude of solar cycle 24. Here we show that cycle predictions can be made more accurate if performed separately for each hemisphere, taking advantage of information about both the dipolar and quadrupolar moments of the solar magnetic field during minimum.

Muñoz-Jaramillo, Andrés; DeLuca, Edward E

2013-01-01

138

Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds  

PubMed Central

Chemically informative J couplings between pairs of quadrupolar nuclei in dimetallic and dimetalloid coordination motifs are measured using J-resolved solid-state NMR experiments. It is shown that the application of a double-quantum filter is necessary to observe the J splittings and that, under these conditions, only a simple doublet is expected. Interestingly, the splitting is amplified if the spins are magnetically equivalent, making it possible to measure highly precise J couplings and unambiguously probe the symmetry of the molecule. This is demonstrated experimentally by chemically breaking the symmetry about a pair of boron spins by reaction with an N-heterocyclic carbene to form a ?-borylation reagent. The results show that the J coupling is a sensitive probe of bonding in diboron compounds and that the J values quantify the weakening of the B–B bond which occurs when forming an sp2–sp3 diboron compound, which is relevant to their reactivity. Due to the prevalence of quadrupolar nuclei among transition metals, this work also provides a new approach to probe metal–metal bonding; results for Mn2(CO)10 are provided as an example. PMID:23919916

2013-01-01

139

Modeling Dipolar and Quadrupolar Defect Structures generated by Chiral Islands in Freely-Suspended Liquid Crystal Films  

E-print Network

We report a detailed theoretical analysis of novel quadrupolar interactions observed between islands, which are disk-like inclusions of extra layers, floating in thin, freely suspended smectic C liquid crystal films. Strong tangential anchoring at the island boundaries result in a strength +1 chiral defect in each island and a companion -1 defect in the film, these forming a topological dipole. While islands of the same handedness form linear chains with the topological dipoles pointing in the same direction, as reported in the literature, islands with different handedness form compact quadrupolar structures with the associated dipoles pointing in opposite directions. The interaction between such heterochiral island--defect pairs is complex, with the defects moving to minimize the director field distortion as the distance between the islands changes. The details of the inter-island potential and the trajectories of the -1 defects depend strongly on the elastic anisotropy of the liquid crystal, which can be modified in the experiments by varying the material chirality of the liquid crystal. A Landau model that describes the energetics of freely mobile defects is solved numerically to find equilibrium configurations for a wide range of parameters.

N. M. Silvestre; P. Patricio; M. M. Telo da Gama; A. Pattanaporkrattana; C. S. Park; J. E. Maclennan; N. A. Clark

2009-04-17

140

31P Differential Line Broadening in the Presence of the 59Co Quadrupolar-CSA Interference in Tetrahedral Clusters  

NASA Astrophysics Data System (ADS)

The first investigation and analysis of the effects, theoretically predicted by Werbelow et al.[ J. Chem. Soc. Faraday Trans.83, 871 (1987)], of interference terms on the lineshape of a spin 1/2 coupled to a high-spin nucleus undergoing quadrupolar and chemical-shift anisotropy (CSA) relaxations are reported for three tetrahedral clusters HFeCo 3(CO) 11L with L = PPh 2H (1), L = PCy 2H (2), and L = PPh 3(3) (Cy = cyclohexyl). For these clusters in solution, an unusual asymmetric broad NMR multiplet of the 31P nucleus scalar-coupled to a 59Co nucleus is observed. It is shown that the 59Co CSA-quadrupolar interference term is the origin of the asymmetry of the 31P spectra. The analysis of the lineshape of the 1H-decoupled spectra gives the spin-coupling constants 1J( 31P- 59Co) and the CSA contribution to the 59Co relaxation. Experimental measurements of T1and of the linewidths for cobalt-59 are reported and support these findings.

Granger, Pierre; Elbayed, Karim; Raya, Jésus; Kempgens, Pierre; Rosé, Jacky

141

From bipolar to quadrupolar electrode structures: an application of bond-detach lithography for dielectrophoretic particle assembly.  

PubMed

We describe a new, simple process for fabricating transparent quadrupolar electrode arrays enabling large-scale particle assembly by means of dielectrophoresis. In the first step, interdigitated electrode arrays are made by chemical wet etching of indium tin oxide (ITO). Then, the transition from a bipolar to a quadrupolar electrode arrangement is obtained by covering the electrode surface with a thin poly(dimethylsiloxane) (PDMS) film acting as an electrical insulation layer in which selective openings are formed using bond-detach lithography. The PDMS insulating layer thickness was optimized and controlled by adjusting experimental parameters such as the PDMS viscosity (modulated by the addition of heptane) and the PDMS spin-coating velocity. The insulating character of the PDMS membrane was successfully demonstrated by performing a dielectrophoretic assembly of polystyrene particles using interdigitated electrodes with and without a PDMS layer. The results show that the patterned PDMS film functions properly as an electrical insulation layer and allows the reconfiguration of the electric field cartography. Electric field simulations were performed in both configurations to predict the dielectrophoretic behavior of the particles. The simulation results are in perfect agreement with experiments, in which we demonstrated the formation of concentrated clusters of polystyrene particles and living cells of regular size and shape. PMID:24758738

Menad, Samia; El-Gaddar, Amal; Haddour, Naoufel; Toru, Sylvain; Brun, Mathieu; Buret, François; Frenea-Robin, Marie

2014-05-20

142

Evidence for spiral magnetic order in the heavy fermion material CeRhIn5 N. J. Curro,1  

E-print Network

Evidence for spiral magnetic order in the heavy fermion material CeRhIn5 N. J. Curro,1 P. C. Hammel In nuclear quadrupolar resonance measurements of the heavy fermion compound CeRhIn5 in the paramagnetic. The interplay between magnetism and superconductivity in heavy fermion materials has attracted much interest

Hammel, P. Chris

143

Impurity model for Mn ions: Possibility of charge order and lattice distortions  

SciTech Connect

Mixed valent manganese ions play an important role in the magnetoresistance of LaMnO{sub 3}-based systems. We consider a Mn impurity with the Mn{sup 4+} represented by a spin S=3/2 (three localized 3d-t{sub 2g} electrons) and the Mn{sup 3+} configuration having an additional localized 3d-e{sub g} electron to form a total spin (S+1/2). The e{sub g} electron hybridizes with conduction electrons (representing the crystal), giving rise to a quadrupolar Kondo effect. The formation of the quadrupolar singlet interferes with the usual spin Kondo effect. Using the noncrossing diagram approximation, we calculate the ground state energy, valence, charge susceptibility, and the quadrupolar susceptibility as a function of the energy of the e{sub g} level for H{r_arrow}0 and compare it to results for H=0 and the ferromagnetic lattice. Both, the charge and quadrupolar susceptibilities, are larger in the spin-polarized limit, indicating that this state is more favorable for charge order and lattice distortions. {copyright} {ital 1999 American Institute of Physics.}

Schlottmann, P. [Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States)] [Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States)

1999-04-01

144

Direct and quantitative determination of the orbital ordering in CeB6 by X-ray diffraction  

Microsoft Academic Search

Results of non-resonant X-ray Bragg diffraction by CeB6 are reported. This material has been described in terms of a simple antiferro-quadrupolar order below TQ = 3.2 K. We determine for the first time, directly and quantitatively the orbital ordering in this material. In particular, we find direct evidence for a simultaneous ordering of a quadrupole (QP) and a hexadecapole (HDP)

Y. Tanaka; U. Staub; K. Katsumata; S. W. Lovesey; J. E. Lorenzo; Y. Narumi; V. Scagnoli; S. Shimomura; Y. Tabata; Y. Onuki; Y. Kuramoto; A. Kikkawa; T. Ishikawa; H. Kitamura

2004-01-01

145

Implementation of controlled phase shift gates and Collins version of Deutsch-Jozsa algorithm on a quadrupolar spin-7/2 nucleus using non-adiabatic geometric phases  

E-print Network

In this work Controlled phase shift gates are implemented on a qaudrupolar system, by using non-adiabatic geometric phases. A general procedure is given, for implementing controlled phase shift gates in an 'N' level system. The utility of such controlled phase shift gates, is demonstrated here by implementing 3-qubit Deutsch-Jozsa algorithm on a 7/2 quadrupolar nucleus oriented in a liquid crystal matrix.

T. Gopinath; Anil Kumar

2009-09-22

146

{open_quotes}Quadrupoled{close_quotes} materials for second-order nonlinear optics  

SciTech Connect

We describe a new approach to second-order nonlinear optical materials, namely quadrupoling. This approach is valid in the regime of Kleinman (full permutation) symmetry breaking, and thus requires a two- or three dimensional microscopic nonlinearity at wavelengths away from material resonances. This {open_quotes}quadrupolar{close_quotes} nonlinearity arises from the second rank pseudotensor of the rotationally invariant representation of the second-order nonlinear optical tensor. We have experimentally investigated candidate molecules comprised of chiral camphorquinone derivatives by measuring the scalar invariant associated with the rank two pseudotensor using hyper-Rayleigh scattering. We have found sizable scalar figures of merit for several compounds using light for which the second harmonic wavelengths are greater than 100 nm longer than the absorption peak location. At these wavelengths, the quadrupolar scalar is as large as the polar (EFISH) scalar of p-nitroaniline. Prospects for applications are discussed.

Hubbard, S.F.; Petschek, R.G.; Singer, K.D. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Physics] [and others

1997-10-01

147

AN ENVELOPE DISRUPTED BY A QUADRUPOLAR OUTFLOW IN THE PRE-PLANETARY NEBULA IRAS 19475+3119  

SciTech Connect

IRAS 19475+3119 is a quadrupolar pre-planetary nebula (PPN), with two bipolar lobes, one in the east-west (E-W) direction and one in the southeast-northwest (SE-NW) direction. We have observed it in CO J = 2-1 with the Submillimeter Array at {approx}1'' resolution. The E-W bipolar lobe is known to trace a bipolar outflow and it is detected at high velocity. The SE-NW bipolar lobe appears at low velocity, and could trace a bipolar outflow moving in the plane of the sky. Two compact clumps are seen at low velocity around the common waist of the two bipolar lobes, spatially coincident with the two emission peaks in the NIR, tracing dense envelope material. They are found to trace the two limb-brightened edges of a slowly expanding torus-like circumstellar envelope produced in the late asymptotic giant branch phase. This torus-like envelope originally could be either a torus or a spherical shell, and it appears as it is now because of the two pairs of cavities along the two bipolar lobes. Thus, the envelope appears to be disrupted by the two bipolar outflows in the PPN phase.

Hsu, Ming-Chien; Lee, Chin-Fei, E-mail: mchsu@asiaa.sinica.edu.tw, E-mail: cflee@asiaa.sinica.edu.tw [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China)

2011-07-20

148

Effect of strongly coupled plasma on the magnetic dipolar and quadrupolar transitions of two-electron ions  

SciTech Connect

Effect of strongly coupled plasma on the excitation energies and transition probabilities for the respective transitions 1s{sup 2}:{sup 1}S{sup e}{yields} 1sns:{sup 3}S{sup e} (n = 2, 3, 4) and 1s{sup 2}:{sup 1}S{sup e}{yields} 1snp:{sup 3}P{sup o} (n = 2, 3, 4) allowed by magnetic dipolar and quadrupolar excitations have been analyzed for the first time for the two-electron ions C{sup 4+}, O{sup 6+}, Ne{sup 8+}, Mg{sup 10+}, Si{sup 12+}, and S{sup 14+}. Time dependent Hatree-Fock theory within variational approach has been adopted for such a study. The effect of surrounding plasma has been treated through the standard Ion-Sphere (IS) model of the plasma where the plasma density is varied systematically from a low value to a pretty high value such that the respective excited states go over to continuum due to such a confinement. The effect of external pressure generated due to plasma confinement on the estimated spectral properties has been analyzed systematically.

Saha, Jayanta K.; Mukherjee, T. K. [Department of Physics, Narula Institute of Technology, Agarpara, Kolkata 700 109, West Bengal (India); Mukherjee, P. K. [Department of Physics, Ramakrishna Mission Vivekananda University, Belur Math, Howrah 711202, West Bengal (India); Department of Mathematics, Visva Bharati, Santiniketan 731235, West Bengal (India); Fricke, B. [Institute fur Physik, Universitat Kassel, 34109 Kassel (Germany)

2013-04-15

149

Second-order quadrupole interaction based detection of ultra-slow motions: Tensor operator framework for central-transition spectroscopy and the dynamics in hexagonal ice as an experimental example  

NASA Astrophysics Data System (ADS)

The second-order quadrupolar broadening of the central transition of nuclear probes with half-integer spins I is demonstrated to be useful to detect ultraslow molecular motions. On the basis of density matrix calculations explicit expressions are derived for quadrupolarly modulated sin-sin and cos-cos signals of selectively excited nuclei with I = 3/2, 5/2, 7/2, and 9/2. These correlation functions are suitable for implementation in two-dimensional exchange spectroscopy as well as for stimulated-echo experiments. As an application, 17O measurements of the reorientational correlation function of water molecules in hexagonal ice are presented.

Adjei-Acheamfour, Mischa; Böhmer, Roland

2014-12-01

150

Deuterium nuclear magnetic resonance of specifically labeled native collagen. Investigation of protein molecular dynamics using the quadrupolar echo technique.  

PubMed Central

Collagen was labeled with [3,3,3-d3]alanine and with [d10]leucine via tissue culture. 2H nuclear magnetic resonance (NMR) spectra were obtained of collagen in solution and as fibrils using the quadrupolar echo technique. The 2H NMR data for [3,3,3-d3]alanine-labeled collagen fibrils were analyzed in terms of a model for motion in which the molecule is considered to jump between two sites, separated azimuthally by an angle 2 delta, in a time which is rapid compared with the residence time in both sites. The data suggest that the molecule undergoes reorientation over an angle, 2 delta, of approximately 30 degrees in the fibrils, and that the average angle between the alanine C alpha--C beta bond axis and the long axis of the helix is approximately 75 degrees. Reorientation is possibly segmental. The T2 for [3,3,3-d3]alanine-labeled collagen fibrils was estimated to be 105 mus. The 2H NMR data for the methyl groups of [d10]leucine-labeled collagen were analyzed qualitatively. These data established that for collagen in solution and as fibrils, rotation occurs about the leucine side-chain bonds, in addition to threefold methyl rotation and reorientation of the peptide backbone. The T2 for the methyl groups of leucine-labeled collagen is estimated to be approximately 130 mus. Taken together, these data provide strong evidence that both polypeptide backbone reorientation and amino acid side-chain motion occur in collagen molecules in the fibrils. Stabilizing interactions that determine fibril structure must therefore depend upon at least two sets of contacts in any given local region. PMID:7248459

Jelinski, L W; Sullivan, C E; Batchelder, L S; Torchia, D A

1980-01-01

151

Molecular modelling and simulation of the surface tension of real quadrupolar fluids  

E-print Network

Molecular modelling and simulation of the surface tension of fluids with force fields is discussed. 29 real fluids are studied, including nitrogen, oxygen, carbon dioxide, carbon monoxide, fluorine, chlorine, bromine, iodine, ethane, ethylene, acetylene, propyne, propylene, propadiene, carbon disulfide, sulfur hexafluoride, and many refrigerants. The fluids are represented by two-centre Lennard-Jones plus point quadrupole models from the literature. These models were adjusted only to experimental data of the vapour pressure and saturated liquid density so that the results for the surface tension are predictions. The deviations between the predictions and experimental data for the surface tension are of the order of 20 percent. The surface tension is usually overestimated by the models. For further improvements, data on the surface tension can be included in the model development. A suitable strategy for this is multi-criteria optimization based on Pareto sets. This is demonstrated using the model for carbon d...

Werth, Stephan; Klein, Peter; Küfer, Karl-Heinz; Horsch, Martin; Hasse, Hans

2014-01-01

152

Molecular modelling and simulation of the surface tension of real quadrupolar fluids  

E-print Network

Molecular modelling and simulation of the surface tension of fluids with force fields is discussed. 29 real fluids are studied, including nitrogen, oxygen, carbon dioxide, carbon monoxide, fluorine, chlorine, bromine, iodine, ethane, ethylene, acetylene, propyne, propylene, propadiene, carbon disulfide, sulfur hexafluoride, and many refrigerants. The fluids are represented by two-centre Lennard-Jones plus point quadrupole models from the literature. These models were adjusted only to experimental data of the vapour pressure and saturated liquid density so that the results for the surface tension are predictions. The deviations between the predictions and experimental data for the surface tension are of the order of 20 percent. The surface tension is usually overestimated by the models. For further improvements, data on the surface tension can be included in the model development. A suitable strategy for this is multi-criteria optimization based on Pareto sets. This is demonstrated using the model for carbon dioxide as an example.

Stephan Werth; Katrin Stöbener; Peter Klein; Karl-Heinz Küfer; Martin Horsch; Hans Hasse

2014-08-21

153

Unusual anisotropic magnetoresistance in charge-orbital ordered Nd0.5Sr0.5MnO3 polycrystals  

NASA Astrophysics Data System (ADS)

Due to its potential application in magnetic recording and sensing technologies, the anisotropic magnetoresistance (AMR) effect has attracted lasting attention. Despite the long history, AMR effect has not been fully understood especially in the unconventional materials, such as perovskite manganites. Here, we report an unusual AMR effect in the charge-orbital ordered (COO) Nd0.5Sr0.5MnO3 polycrystals, which is observed when the magnetic field rotates in the plane that is perpendicular to the current (out-of-plane AMR). Despite being a polycrystalline sample where no anisotropy is expected, the resistivity shows a large irreversible drop with rotating magnetic field. A model has been proposed based on anisotropic magnetic field induced the melting of COO phase to explain the unusual out-of-plane AMR successfully. Our results demonstrate a new way for understanding the close relationship between phase separation and AMR effect in COO manganites.

Yang, Huali; Wang, Baomin; Liu, Yiwei; Yang, Zhihuan; Zhu, Xiaojian; Xie, Yali; Zuo, Zhenghu; Chen, Bin; Zhan, Qingfeng; Wang, Junling; Li, Run-Wei

2014-12-01

154

Effect of an electric field on the surface tension of a dipolar-quadrupolar fluid and its implication for sign preference in droplet nucleation.  

PubMed

The effect of a uniform electric field on interfacial properties of dipolar-quadrupolar fluids is investigated by using the density-functional theory. As in the case of purely dipolar fluids the (thermodynamic) surface tension is always altered by the external field, regardless of the direction of the field. However, unlike the purely dipolar fluids, for two given external fields with the same strength but exactly opposite direction the magnitude of variation in the surface tension is different. This apparent symmetry breaking by reversing the field direction suggests a new molecular mechanism to explain the phenomenon of sign preference in droplet formation on charged condensation centers. PMID:12484961

Warshavsky, V B; Zeng, X C

2002-12-01

155

Johannes Richter, Oleg Derzhko and Jorg Schulenburg MAGNETIC-FIELD INDUCED SPIN-PEIERLS INSTABILITY  

E-print Network

i i ¡ ¢ £ ¤¥ I I ' & $ % Johannes Richter, Oleg Derzhko and J¨org Schulenburg MAGNETIC lattices Johannes Richter, Oleg Derzhko and J¨org Schulenburg Abstract. For a class of frustrated rigorous analytical results completed by large-scale exact diago- nalization data for lattices up to N = 54

156

Phonon spectrum of the QCD vacuum in a magnetic-field-induced superconducting phase  

NASA Astrophysics Data System (ADS)

In the background of a sufficiently strong magnetic field the vacuum was suggested to become an ideal electric conductor (highly anisotropic superconductor) due to an interplay between the strong and electromagnetic forces. The superconducting ground state resembles an Abrikosov lattice state in an ordinary type-II superconductor: it is an inhomogeneous structure made of a (charged vector) quark-antiquark condensate pierced by vortices. In this paper the acoustic (phonon) vibrational modes of the vortex lattice are studied at zero temperature. Using an effective model based on a vector meson dominance, we show that in the infrared limit the longitudinal (transverse) acoustic vibrations of the vortex lattice possess a linear (quadratic) dispersion relation corresponding to type-I (type-II) Nambu-Goldstone modes.

Chernodub, M. N.; Van Doorsselaere, Jos; Verschelde, Henri

2014-05-01

157

Phonon spectrum of QCD vacuum in magnetic-field-induced superconducting phase  

E-print Network

In the background of a sufficiently strong magnetic field the vacuum was suggested to become an ideal electric conductor (highly anisotropic superconductor) due to an interplay between the strong and electromagnetic forces. The superconducting ground state resembles an Abrikosov lattice state in an ordinary type-II superconductor: it is an inhomogeneous structure made of a (charged vector) quark-antiquark condensate pierced by vortices. In this paper the acoustic (phonon) vibrational modes of the vortex lattice are studied in the mean-field approach at zero temperature. Using an effective model based on a vector meson dominance, we show that in the infrared limit the longitudinal (transverse) acoustic vibrations of the vortex lattice possess a linear (quadratic) dispersion relation corresponding to type I (type II) Nambu-Goldstone modes.

Chernodub, M N; Verschelde, Henri

2014-01-01

158

On magnetic-field-induced dissipationless electric current in helicoidal graphene nanoribbons  

E-print Network

We argue that twisted (helicoidal) graphene nanoribbons may support dissipationless electric current in the presence of static uniform magnetic field. The non-resistive charge transfer in this parity-odd system should be enhanced by thermal fluctuations.

M. N. Chernodub

2013-04-05

159

Glass-ceramic-mediated, magnetic-field-induced localized hyperthermia: response of a murine mammary carcinoma  

SciTech Connect

Hyperthermia has found to be a useful modality for cancer therapy. In this report, a biocompatible, ferrimagnetic glass-ceramic capable of inducing localized hyperthermia by hysteresis heating upon exposure to an alternating magnetic field is presented. When the glass-ceramic was placed in the region of a subcutaneously transplanted, weakly antigenic breast carcinoma and subjected to the magnetic field, sufficient temperature rise was obtained to cause significant (approx.50%) tumor regrowth delay and a 12% permanent control. The data demonstrate that glass-ceramic-mediated hysteresis heating may be a useful therapeutic approach in the treatment of cancer which offers the advantage of producing a highly localized and predictable tumor volume hyperthermia.

Luderer, A.A. (Corning Glass Works, Corning, NY); Borrelli, N.F.; Panzarino, J.N.; Mansfield, G.R.; Hess, D.M.; Brown, J.L.; Barnett, E.H.; Hahn, E.W.

1983-04-01

160

Glass-ceramic-mediated, magnetic-field-induced localized hyperthermia: response of a murine mammary carcinoma  

Microsoft Academic Search

Hyperthermia has found to be a useful modality for cancer therapy. In this report, a biocompatible, ferrimagnetic glass-ceramic capable of inducing localized hyperthermia by hysteresis heating upon exposure to an alternating magnetic field is presented. When the glass-ceramic was placed in the region of a subcutaneously transplanted, weakly antigenic breast carcinoma and subjected to the magnetic field, sufficient temperature rise

A. A. Luderer; N. F. Borrelli; J. N. Panzarino; G. R. Mansfield; D. M. Hess; J. L. Brown; E. H. Barnett; E. W. Hahn

1983-01-01

161

Enhanced magnetic-field-induced optical properties of nanostructured magnetic fluids by doping nematic liquid crystals  

PubMed Central

Ferronematic materials composed of 4-cyano-4?-pentylbiphenyl nematic liquid crystal and oil-based Fe3O4 magnetic fluid were prepared using ultrasonic agitation. The birefringence (?n) and figure of merit of optical properties (Q?=??n/?, where ? is the extinction coefficient) of pure magnetic fluids and the as-prepared ferronematic materials were examined and compared. The figure of merit of optical properties weighs the birefringence and extinction of the materials and is more appropriate to evaluate their optical properties. Similar magnetic-field- and magnetic-particle-concentration-dependent properties of birefringence and figure of merit of optical properties were obtained for the pure magnetic fluids and the ferronematic materials. For the ferronematic materials, the values of Q increase with the volume fractions of nematic liquid crystal under certain fixed field strength and are larger than those of their corresponding pure magnetic fluids at high field region. In addition, the enhancement of Q value increases monotonously with the magnetic field and becomes remarkable when the applied magnetic field is beyond 50 mT. The maximum relative enhanced value of QR exceeds 6.8% in our experiments. The results of this work may conduce to extend the pragmatic applications of nanostructured magnetic fluids in optical field. PMID:22587542

2012-01-01

162

Magnetic fluid hyperthermia (MFH): Cancer treatment with AC magnetic field induced excitation of biocompatible superparamagnetic nanoparticles  

Microsoft Academic Search

The story of hyperthermia with small particles in AC magnetic fields started in the late 1950s, but most of the studies were unfortunately conducted with inadequate animal systems, inexact thermometry and poor AC magnetic field parameters, so that any clinical implication was far behind the horizon.More than three decades later, it was found, that colloidal dispersions of superparamagnetic (subdomain) iron

Andreas Jordan; Regina Scholz; Peter Wust; Horst Fähling; Roland Felix

1999-01-01

163

Magnetic-Field-Induced Metal-Insulator Transitions in Multiple-Quantum-Well Structures  

NASA Astrophysics Data System (ADS)

Far infrared spectroscopy and electrical transport measurements on a set of modulation-doped GaAs/Al0.3Ga0.7As multiple-quantum-well structures show metallic and insulating behavior that depends on doping density and magnetic field; impurity band insulator, impurity band metal, and quantum Hall conductor states are observed. In the latter case a plateau around filling factor 1 shows entrance to an insulating state at higher fields; this result is compared with the global phase diagram for the quantum Hall effect. A general phase diagram that encompasses lower doping densities is suggested.

Wang, Y. J.; McCombe, B. D.; Meisels, R.; Kuchar, F.; Schaff, W.

1995-07-01

164

Magnetic field-induced superconductivity in the ferromagnet URhGe.  

PubMed

In several metals, including URhGe, superconductivity has recently been observed to appear and coexist with ferromagnetism at temperatures well below that at which the ferromagnetic state forms. However, the material characteristics leading to such a state of coexistence have not yet been fully elucidated. We report that in URhGe there is a magnetic transition where the direction of the spin axis changes when a magnetic field of 12 tesla is applied parallel to the crystal b axis. We also report that a second pocket of superconductivity occurs at low temperature for a range of fields enveloping this magnetic transition, well above the field of 2 tesla at which superconductivity is first destroyed. Our findings strongly suggest that excitations in which the spins rotate stimulate superconductivity in the neighborhood of a quantum phase transition under high magnetic field. PMID:16123293

Lévy, F; Sheikin, I; Grenier, B; Huxley, A D

2005-08-26

165

Pressure-magnetic field induced phase transformation in Ni46Mn41In13 Heusler alloy  

NASA Astrophysics Data System (ADS)

The effect of hydrostatic pressure and magnetic field on the magnetic properties and phase transformation in Ni46Mn41In13 Heusler alloy was investigated. Pressure (P)-magnetic field (H)-temperature (T) phase diagram has been constructed from experimental results. In the P-T contour of the phase diagram, the slope of the austenite-martensite phase boundary line appears positive (dT/dP > 0), while it appears negative (dT/dH < 0) in the H-T contour. The results revealed that pressure and magnetic field have opposite effect on phase stabilization. The combined effect of pressure and magnetic field on martensitic transition has led to two important findings: (i) pressure dependent shift of austenite start temperature (As) is higher when larger field is applied, and (ii) field dependent shift of As is lowered when a higher pressure is applied. The pressure and magnetic field dependent shift observed in the martensitic transformation has been explained on the basis of thermodynamic calculations. Curie temperature of the phases was found to increase with pressure at a rate of 0.6 K/kbar.

Rama Rao, N. V.; Manivel Raja, M.; Esakki Muthu, S.; Arumugam, S.; Pandian, S.

2014-12-01

166

Magnetic fluid hyperthermia (MFH): Cancer treatment with AC magnetic field induced excitation of biocompatible superparamagnetic nanoparticles  

NASA Astrophysics Data System (ADS)

The story of hyperthermia with small particles in AC magnetic fields started in the late 1950s, but most of the studies were unfortunately conducted with inadequate animal systems, inexact thermometry and poor AC magnetic field parameters, so that any clinical implication was far behind the horizon. More than three decades later, it was found, that colloidal dispersions of superparamagnetic (subdomain) iron oxide nanoparticles exhibit an extraordinary specific absorption rate (SAR [ W/ g]), which is much higher at clinically tolerable H 0 f combinations in comparison to hysteresis heating of larger multidomain particles. This was the renaissance of a cancer treatment method, which has gained more and more attention in the last few years. Due to the increasing number of randomized clinical trials preferentially in Europe with conventional E-field hyperthermia systems, the general medical and physical experience in hyperthermia application is also rapidly growing. Taking this increasing clinical experience carefully into account together with the huge amount of new biological data on heat response of cells and tissues, the approach of magnetic fluid hyperthermia (MFH) is nowadays more promising than ever before. The present contribution reviews the current state of the art and some of the future perspectives supported by advanced methods of the so-called nanotechnology.

Jordan, Andreas; Scholz, Regina; Wust, Peter; Fähling, Horst; Felix, Roland

1999-07-01

167

Technique for azimuthal anchoring measurement of nematic liquid crystals using magnetic field induced deformation  

NASA Astrophysics Data System (ADS)

The authors devised a technique for measuring the azimuthal anchoring coefficient of nematic liquid crystals. The coefficient was estimated calculating the varying ratio of magnetic coherence length to extrapolation length using light transmission to magnetic field. The paralleled control of the directors on the entrance surface, polarizer axis and magnetic field enables the transmission to sensitively reflect the anchoring. The extrapolation length was 0.48?m for polyimide rubbed surface, 0.56?m for rubbed poly-vinyl alcohol and 5.6?m for photo-aligned polyimide. This technique has advantages such as insensitiveness to sample adjustment, covering wide range of anchoring and independence on the cell gap, electrodes and impurity.

Kim, Jong-Hyun; Choi, Hyunchul

2007-03-01

168

Reducing magnetic field induced noise in broad-band seismic recordings  

NASA Astrophysics Data System (ADS)

Seismic broad-band sensors are known to be sensitive to the magnetic field. Magnetic storms and man-made disturbances of the magnetic field can produce significant noise in seismic recordings. I show that variations in the magnetic field translate directly into apparent acceleration of the seismic sensor within the period range from 60 to 1200s for all leaf-spring sensors under investigation. For a Streckeisen STS-1V this is shown even for periods down to 1s. The sensitivity is quantified in magnitude and direction. Both are quite stable over many time windows and signal periods. The sensitivities obtained by linear regression of the acceleration signal on magnetic field recordings during a magnetic storm can effectively be applied to reduce noise in seismic signals. The sensitivity varies in magnitude from sensor to sensor but all are in the range from 0.05 to 1.2ms-2T-1. Seismograms from sensors at Black Forest Observatory (BFO) and stations of the German Regional Seismic Network were investigated. Although these are mainly equipped with leaf-spring sensors, the problem is not limited to this type of instrument. The effect is not observable on the horizontal component STS-1s at BFO while it is significant in the recordings of the vertical STS-1. The main difference between these instruments is the leaf-spring suspension in the vertical component that appears to be the source of the trouble. The suspension springs are made of temperature compensated Elinvar alloys that inherently are ferromagnetic and may respond to the magnetic field in various ways. However, the LaCoste Romberg ET-19 gravimeter at BFO, which uses this material too, does not respond to magnetic storms at a similar magnitude neither do the Invar-wire strainmeters. An active shielding, composed of three Helmholtz coils and a feedback system, is installed at station Stuttgart and provides an improvement of signal-to-noise ratio by almost a factor of 20 at this particular station. The passive Permalloy shielding commonly installed with STS-1V sensors performs similarly well.

Forbriger, Thomas

2007-04-01

169

Magnetic field induced discontinuous spin reorientation in ErFeO{sub 3} single crystal  

SciTech Connect

The spin reorientation of ErFeO{sub 3} that spontaneously occurs at low temperature has been previously determined to be a process involving the continuous rotation of Fe{sup 3+} spins. In this work, the dynamic process of spin reorientation in ErFeO{sub 3} single crystal has been investigated by AC susceptibility measurements at various frequencies and static magnetic fields. Interestingly, two completely discontinuous steps are induced by a relatively large static magnetic field due to the variation in the magnetic anisotropy during this process. It provides deeper insights into the intriguing magnetic exchange interactions which dominate the sophisticated magnetic phase transitions in the orthoferrite systems.

Shen, Hui [School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418 (China) [School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418 (China); Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2500 (Australia); Cheng, Zhenxiang, E-mail: cheng@uow.edu.au; Hong, Fang; Wang, Xiaolin [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2500 (Australia)] [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2500 (Australia); Xu, Jiayue [School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418 (China)] [School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418 (China); Yuan, Shujuan; Cao, Shixun [Department of Physics, Shanghai University, Shanghai 200444 (China)] [Department of Physics, Shanghai University, Shanghai 200444 (China)

2013-11-04

170

Magnetic-field-induced microstructural features in a high carbon steel during diffusional phase transformation  

NASA Astrophysics Data System (ADS)

In this work, a high purity, high carbon steel was heat treated without and with a 12-T magnetic field. The microstructural features induced by magnetic field during its diffusion-controlled austenite decomposition were investigated by means of optical microscopy and SEM/EBSD. It is found that the magnetic field increases the amount of the abnormal structure, which is composed of proeutectoid cementite along the prior austenite boundaries and ferrite around it, because magnetic field increases the austenite grain size and promotes the transformation of carbon-depleted austenite to ferrite. No specific orientation relationship between abnormal ferrite and cementite has been found in the non-field- or the field-treated specimens. Magnetic field evidently promotes the spheroidization of pearlite, due to its effect of enhancing carbon diffusion through raising the transformation temperature and its effect of increasing the relative ferrite/cementite interface energy. As magnetic field favors the nucleation of the high magnetization phase-pearlitic ferrite, the occurrence of the P-P2 OR that corresponds to the situation that ferrite nucleates prior to cementite during pearlitic transformation is enhanced by the magnetic field.

Zhang, Xiaoxue; Zhang, Yudong; Gong, Minglong; Esling, Claude; Zhao, Xiang; Zuo, Liang

2012-12-01

171

Weak extremely-low-frequency magnetic field-induced regeneration anomalies in the planarian, Dugesia tigrina  

SciTech Connect

The authors recently reported that cephalic regeneration in the planarian Dugesia tigrina was significantly delayed in populations exposed continuously to combined parallel DC and AC magnetic fields. This effect was consistent with hypotheses suggesting an underlying resonance phenomenon. The authors report here, in a parallel series of investigations on the same model system, that the incidence of regeneration anomalies presenting as tumor-like protuberances also increases significantly (P < .001) in association with exposure to weak 60 Hz magnetic fields, with peak intensities ranging between 1.0 and 80.0 {micro}T. These anomalies often culminate in the complete disaggregation of the organism. Similar to regeneration rate effects, the incidence of regeneration anomalies is specifically dependent upon the planaria possessing a fixed orientation with respect to the applied magnetic field vectors. However, unlike the regeneration rate effects, the AC magnetic field alone, in the absence of any measurable DC field, is capable of producing these anomalies. Moreover, the incidence of regeneration anomalies follows a clear dose-response relationship as a function of AC magnetic field intensity, with the threshold for induced electric field intensity estimated at 5 {micro} V/m. The addition of either 51.1 or 78.4 {micro}T DC magnetic fields, applied in parallel combination with the AC field, enhances the appearance of anomalies relative to the 60 Hz AC field alone, but only at certain AC field intensities. Thus, whereas the previous study of regeneration rate effects appeared to involve exclusively resonance interactions, the regeneration anomalies reported here appear to result primarily from Faraday induction coupling.

Jenrow, K.A.; Smith, C.H.; Liboff, A.R. [Oakland Univ., Rochester, MI (United States). Dept. of Physics] [Oakland Univ., Rochester, MI (United States). Dept. of Physics

1996-12-31

172

Magnetic field induced nutation of exciton-polariton polarization in (Cd,Zn)Te crystals  

NASA Astrophysics Data System (ADS)

We study the polarization dynamics of exciton-polaritons propagating in sub-mm-thick (Cd,Zn)Te bulk crystals using polarimetric time-of-flight techniques. The application of a magnetic field in Faraday geometry leads to synchronous temporal oscillations of all Stokes parameters of an initially linearly or circularly polarized, spectrally broad optical pulse of 150-fs duration propagating through the crystal. Strong dispersion for photon energies close to the exciton resonance leads to stretching of the optical pulse to a duration of 200-300 ps and enhancement of magneto-optical effects such as the Faraday rotation and the nonreciprocal birefringence. The oscillation frequency of the exciton-polariton polarization increases with magnetic field B, reaching 10 GHz at B˜5 T. Surprisingly, the relative contributions of Faraday rotation and nonreciprocal birefringence undergo strong changes with photon energy, which is attributed to a nontrivial spectral dependence of Faraday rotation in the vicinity of the exciton resonance. This leads to polarization nutation of the transmitted optical pulse in the time domain. The results are well explained by a model that accounts for Faraday rotation and magnetospatial dispersion in zinc-blende crystals. We evaluate the exciton g factor |gexc|=0.2 and the magnetospatial constant |V|=5×10-12 eV cm T-1.

Godde, T.; Glazov, M. M.; Akimov, I. A.; Yakovlev, D. R.; Mariette, H.; Bayer, M.

2013-10-01

173

X?CT analysis of magnetic field-induced phase transitions in magnetorheological elastomers  

Microsoft Academic Search

The phase behavior of polymer solutions and composites is a complex issue and is of both technological and fundamental interest. For a better understanding of the microstructure formation in magnetorheological (MR) elastomers, x-ray micro-computed tomography (X?CT) investigations were carried out. Magnetorheological elastomers with 5% mass content of iron powder were prepared under different magnetic field strengths between 1 and 220

T Borbáth; S Günther; D Yu Borin; Th Gundermann; S Odenbach

2012-01-01

174

Magnetic field-induced giant enhancement of electron-phonon energy transfer in strongly disordered conductors.  

PubMed

Relaxation of soft modes (e.g., charge density in gated semiconductor heterostructures, spin density in the presence of magnetic field) slowed down by disorder may lead to giant enhancement of energy transfer (cooling power) between overheated electrons and phonons at low bath temperature. We show that in strongly disordered systems with time-reversal symmetry broken by external or intrinsic exchange magnetic field the cooling power can be greatly enhanced. The enhancement factor as large as 10(2) at magnetic field B~10 T in 2D InSb films is predicted. A similar enhancement is found for the ultrasound attenuation. PMID:24182289

Shtyk, A V; Feigel'man, M V; Kravtsov, V E

2013-10-18

175

Phonon spectrum of QCD vacuum in magnetic-field-induced superconducting phase  

E-print Network

In the background of a sufficiently strong magnetic field the vacuum was suggested to become an ideal electric conductor (highly anisotropic superconductor) due to an interplay between the strong and electromagnetic forces. The superconducting ground state resembles an Abrikosov lattice state in an ordinary type--II superconductor: it is an inhomogeneous structure made of a (charged vector) quark-antiquark condensate pierced by vortices. In this paper the acoustic (phonon) vibrational modes of the vortex lattice are studied at zero temperature. Using an effective model based on a vector meson dominance, we show that in the infrared limit the longitudinal (transverse) acoustic vibrations of the vortex lattice possess a linear (quadratic) dispersion relation corresponding to type I (type II) Nambu--Goldstone modes.

M. N. Chernodub; Jos Van Doorsselaere; Henri Verschelde

2014-06-16

176

Particle size and magnetic field-induced optical properties of magnetic fluid nanoparticles.  

PubMed

Magnetite nanoparticles with diameters of 7, 9, and 12 nm have been prepared by a chemical coprecipitation method. The transmission of light through magnetic fluid containing these nanoparticles has been investigated as a function of film thickness with wavelength between 400 and 750 nm, and applied magnetic fields up to 275 Oe. The transmission threshold shifts to the lower wavelength side with decreasing magnetic fluid film thickness as well as the particle size. For a given film thickness, the transmittance increases with increasing magnetic field for films with a particle size of 7 and 9 nm, but decreases in the 12-nm film. This is attributed to the competition between the van der Waals and dipole-dipole interaction. PMID:16241436

Rao, G Narsinga; Yao, Y D; Chen, Y L; Wu, K T; Chen, J W

2005-09-01

177

Random magnetic fields inducing solar neutrino spin-flavor precession in a three generation context  

E-print Network

We study the effect of random magnetic fields in the spin-flavor precession of solar neutrinos in a three generation context, when a non-vanishing transition magnetic moment is assumed. While this kind of precession is strongly constrained when the magnetic moment involves the first family, such constraints do not apply if we suppose a transition magnetic moment between the second and third families. In this scenario we can have a large non-electron anti-neutrino flux arriving on Earth, which can lead to some interesting phenomenological consequences, as, for instance, the suppression of day-night asymmetry. We have analyzed the high energy solar neutrino data and the KamLAND experiment to constrain the solar mixing angle, and solar mass difference, and we have found a larger shift of allowed values.

M. M. Guzzo; P. C. de Holanda; O. L. G. Peres

2005-04-20

178

Efficient correction of inhomogeneous static magnetic field-induced distortion in Echo Planar Imaging.  

PubMed

Single-shot Echo Planar Imaging (EPI) is one of the most efficient magnetic resonance imaging (MRI) acquisition schemes, producing relatively high-definition images in 100 ms or less. These qualities make it desirable for Diffusion Tensor Imaging (DTI), functional MRI (fMRI), and Dynamic Susceptibility Contrast MRI (DSC-MRI). However, EPI suffers from severe spatial and intensity distortion due to B(0) field inhomogeneity induced by magnetic susceptibility variations. Anatomically accurate, undistorted images are essential for relating DTI and fMRI images with anatomical MRI scans, and for spatial registration with other modalities. We present here a fast, robust, and accurate procedure for correcting EPI images from such spatial and intensity distortions. The method involves acquisition of scans with opposite phase encoding polarities, resulting in opposite spatial distortion patterns, and alignment of the resulting images using a fast nonlinear registration procedure. We show that this method, requiring minimal additional scan time, provides superior accuracy relative to the more commonly used, and more time consuming, field mapping approach. This method is also highly computationally efficient, allowing for direct "real-time" implementation on the MRI scanner. We further demonstrate that the proposed method can be used to recover dropouts in gradient echo (BOLD and DSC-MRI) EPI images. PMID:19944768

Holland, Dominic; Kuperman, Joshua M; Dale, Anders M

2010-03-01

179

Magnetic field-induced phase transformation & power harvesting capabilities in magnetic shape memory alloys.  

E-print Network

??Magnetic Shape Memory Alloys (MSMAs) combine shape-change/deformationrecovery abilities of heat driven conventional shape memory alloys (SMA) and magnetic field driven magnetostrictives through martensitic transformation. They… (more)

Basaran, Burak

2011-01-01

180

Dephasing and relaxation of central hole spins by nuclear spin baths in InGaAs quantum dots: role of nuclear quadrupolar coupling  

NASA Astrophysics Data System (ADS)

Single electron or hole spins in III-V semiconductor quantum dots (QDs) are promising candidates for solid-state qubits. Their coherence properties are typically governed by the hyperfine coupling between these ``central'' electronic spins and the dense surrounding bath of lattice nuclear spins. Theoretically this is a challenging problem due to its many-body and strongly-correlated nature. Here we measure the spin dynamics of holes in InGaAs quantum dots by detecting their intrinsic, random spin fluctuations while in thermal equilibrium, which reveals the spin correlation time scales ?h and the functional form of bath-induced spin relaxation. In zero magnetic field, ?h is very long (˜400 ns) and decays exponentially, in marked contrast with recent theories. ?h increases to ˜5 ?s in small (100 G) longitudinal fields, and the spin dynamics evolve to a very slow ˜1/ln(t) decay [1]. We model the influence of nuclear quadrupolar coupling on spin dynamics in these strained QDs for both electrons and holes [2], and find a good agreement with experimental data when the quadrupolar coupling exceeds the hyperfine coupling strength. [1] Yan Li, N. Sinitsyn, et al., PRL 108, 186603 (2012). [2] N. Sinitsyn, Yan Li, et al., PRL 109, 166605 (2012).

Li, Yan; Sinitsyn, N. A.; Saxena, A.; Smith, D. L.; Reuter, D.; Wieck, A. D.; Yakovlev, D. R.; Manfred, B.; Crooker, S. A.

2013-03-01

181

Order-defects-order  

NASA Astrophysics Data System (ADS)

The manifestation of the universal laws of organization of systems (in particular, the law of small integers) and the formation of a crystal from a point is shown by the example of order-disorder-order relations and comparison of the quantitative connectivity relations of vertices in borate radicals and organic polycycles.

Smirnova, N. L.

2008-12-01

182

Magnetic ordering in the frustrated J1-J2 Ising chain candidate BaNd2O4  

NASA Astrophysics Data System (ADS)

The AR2O4 family (R =rare earth) has recently been attracting interest as a new series of frustrated magnets, with the magnetic R atoms forming zigzag chains running along the c axis. We have investigated polycrystalline BaNd2O4 with a combination of magnetization, heat-capacity, and neutron powder diffraction measurements. Magnetic Bragg peaks are observed below TN=1.7K, and they can be indexed with a propagation vector of k?=(0,1/2,1/2). The signal from magnetic diffraction is well described by long-range ordering of only one of the two types of Nd zigzag chains, with collinear up-up-down-down intrachain spin configurations (double Néel state). Furthermore, low-temperature magnetization and heat-capacity measurements reveal two magnetic-field-induced spin transitions at 2.75 and 4 T for T =0.46K. The high-field phase is paramagnetic, while the intermediate-field state may arise from a spin transition of the long-range ordered Nd chains. One possible candidate for the field-induced ordered state corresponds to an up-up-down intrachain spin configuration, as predicted for a classical J1-J2 Ising chain with a double Néel ground state in zero field.

Aczel, A. A.; Li, L.; Garlea, V. O.; Yan, J.-Q.; Weickert, F.; Jaime, M.; Maiorov, B.; Movshovich, R.; Civale, L.; Keppens, V.; Mandrus, D.

2014-10-01

183

Heavy-Fermion Superconductivity in the Quadrupole Ordered State of PrV2Al20  

NASA Astrophysics Data System (ADS)

PrV2Al20 is a rare example of a heavy-fermion system based on strong hybridization between conduction electrons and nonmagnetic quadrupolar moments of the cubic ?3 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 ? 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 ?3 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.

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

2014-12-01

184

Heavy-Fermion Superconductivity in the Quadrupole Ordered State of PrV_{2}Al_{20}.  

PubMed

PrV_{2}Al_{20} is a rare example of a heavy-fermion system based on strong hybridization between conduction electrons and nonmagnetic quadrupolar moments of the cubic ?_{3} ground doublet. Here, we report that a high-quality single crystal of PrV_{2}Al_{20} exhibits superconductivity at T_{c}=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 ?C/T?0.3??J/mol?K^{2} and the effective mass m^{*}/m_{0}?140 estimated from the temperature dependence of the upper critical field. Furthermore, the high-quality single crystals exhibit double transitions at T_{Q}=0.75??K and T^{*}=0.65??K associated with quadrupole and octupole degrees of freedom of the ?_{3} doublet. In the ordered state, the specific heat C/T shows a T^{3} 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. PMID:25615375

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

2014-12-31

185

Pressure-induced heavy fermion superconductivity in the nonmagnetic quadrupolar system PrTi(2)Al(20).  

PubMed

We report the discovery of a pressure-induced heavy fermion superconductivity in a nonmagnetic orbital ordering state in the cubic compound PrTi(2)Al(20). In particular, we found that the transition temperature and the effective mass associated with the superconductivity are dramatically enhanced as the system approaches the putative quantum critical point of the orbital order. Our experiment indicates that the strong orbital fluctuations may provide a nonmagnetic glue for Cooper pairing. PMID:23215319

Matsubayashi, K; Tanaka, T; Sakai, A; Nakatsuji, S; Kubo, Y; Uwatoko, Y

2012-11-01

186

Pseudogap, charge order, and pairing density wave at the hot spots in cuprate superconductors  

NASA Astrophysics Data System (ADS)

We address the timely issue of the presence of charge ordering at the hot spots in the pseudogap phase of cuprate superconductors in the context of an emergent SU(2) symmetry which relates the charge and pairing sectors. Performing the Hubbard-Stratonovich decoupling such that the free energy stays always real and physically meaningful, we exhibit three solutions of the spin-fermion model at hot spots. A careful examination of their stability and free energy shows that, at low temperatures, the system tends towards the coexistence of a charge density wave (CDW) and the composite order parameter made up of the diagonal quadrupolar density wave and pairing fluctuations of K. B. Efetov et al. [Nat. Phys. 9, 442 (2013), 10.1038/nphys2641]. The CDW is sensitive to the shape of the Fermi surface, in contrast to the diagonal quadrupolar order, which is immune to it. SU(2) symmetry within the pseudogap phase also applies to the CDW state, which therefore admits a pairing density p -wave counterpart breaking time-reversal symmetry.

Pépin, C.; de Carvalho, V. S.; Kloss, T.; Montiel, X.

2014-11-01

187

Long-range antiferromagnetic order in the frustrated XY pyrochlore antiferromagnet Er2Ge2O7  

NASA Astrophysics Data System (ADS)

A cubic Er2Ge2O7 pyrochlore was prepared under high-pressure and high-temperature conditions and its magnetic ground state was investigated by measurements of specific heat, dc and ac magnetic susceptibility as functions of temperature, pressure, and magnetic field. We found that Er2Ge2O7 undergoes a long-range antiferromagnetic transition at TN ? 1.4 K, which can be further enhanced by applying external physical pressure. On the other hand, application of external magnetic fields suppresses the antiferromagnetic order to zero temperature around Hc ? 2.3 T, where a magnetic-field-induced spin-flop transition was observed. Hc increases accordingly with increasing TN under external pressure. A comparison of the magnetic ground states and structural variations along the isostructural series Er2B2O7 (B = Sn, Ti, Ge) together with the high-pressure study on Er2Ge2O7 indicated that the magnetic properties of these highly frustrated XY pyrochlore antiferromagnets are very sensitive to the minute structural changes that determine the anisotropic exchange interactions and the local crystal-electric-field environments of Er3+ ions.

Li, X.; Li, W. M.; Matsubayashi, K.; Sato, Y.; Jin, C. Q.; Uwatoko, Y.; Kawae, T.; Hallas, A. M.; Wiebe, C. R.; Arevalo-Lopez, A. M.; Attfield, J. P.; Gardner, J. S.; Freitas, R. S.; Zhou, H. D.; Cheng, J.-G.

2014-02-01

188

The origin of ferromagnetic ordering in PrNi 3.9Cu 1.1  

NASA Astrophysics Data System (ADS)

Although both PrNi 5 and PrCu 5 are non-magnetic, PrNi 5- xCu x alloys for 0.9? x?2.6 were recently discovered to order with Curie temperature T C?3.6 K. In order to understand the mechanism of these ferromagnetic orderings, we have carried out mean-field model calculations and obtained crystal-field parameters and anisotropic Heisenberg coupling constants for x=1.1. The effects of quadrupolar coupling and magneto-elastic interactions were also taken into account in order to better fit the magnetization along the hard [0 0 1] direction. Based on our theoretical studies, we conclude that Cu substitution for Ni strongly changes the crystal field acting on the 4f electrons, and considerably enhances the Pr-Pr exchange interaction. The onset of ferromagnetism below TC is therefore attributed to an interplay between the exchange interactions and crystalline electric field effects.

Liu, Z.-S.; Park, J.-G.

2002-09-01

189

Cratered Lorentzian response of driven microwave superconducting nanowire-bridged resonators: Oscillatory and magnetic-field induced stochastic states  

NASA Astrophysics Data System (ADS)

We report on observations of a superconductor-normal pulsing regime in microwave (GHz) coplanar waveguide resonators consisting of superconducting MoGe films interrupted by a gap that is bridged by one or more suspended superconducting nanowires. This regime, which involves MHz-frequency oscillations in the amplitude of the supercurrent in the resonator, is achieved when the steady-state amplitude of the current in the driven resonator exceeds the critical current of the nanowires. Thus we are able to determine the temperature dependence of the critical current, which agrees well with the corresponding Bardeen formula. The pulsing regime manifests itself as an apparent “crater” on top of the fundamental Lorentzian peak of the resonator. Once the pulsing regime is achieved at a fixed drive power, however, it remains stable for a range of drive frequencies corresponding to subcritical steady-state currents in the resonator. We develop a phenomenological model of resonator-nanowire systems from which we are able to obtain a quantitative description of the amplitude oscillations and also, inter alia, to investigate thermal relaxation processes in superconducting nanowires. For the case of resonators comprising two parallel nanowires and subject to an external magnetic field, we find field-driven oscillations of the onset power for the amplitude oscillations, as well as the occurrence (for values of the magnetic field that strongly frustrate the nanowires) of a distinct steady state in which the pulsing is replaced by stochastic amplitude fluctuations. We conclude by giving a brief discussion of how circuit-quantum electrodynamics-based systems have the potential to facilitate nondestructive measurements of the current-phase relationship of superconducting nanowires and, hence, of the rate at which quantum phase slips take place in superconducting nanowires.

Brenner, Matthew W.; Gopalakrishnan, Sarang; Ku, Jaseung; McArdle, Timothy J.; Eckstein, James N.; Shah, Nayana; Goldbart, Paul M.; Bezryadin, Alexey

2011-05-01

190

FAST TRACK COMMUNICATION: Magnetic field induced ferroelectric to relaxor crossover in Tb1-xCaxMnO3  

NASA Astrophysics Data System (ADS)

The influence of magnetic field on the electrical properties of Tb1-xCaxMnO3 has been investigated by means of dielectric, polarization and neutron diffraction measurements. A field of 6 T applied along the b-axis induces a crossover from ferroelectric to relaxor behavior for the x = 0.02 compound at temperatures close to the ferroelectric transition. The mechanism of this field induced crossover involves a decrease in the coherence length of the Mn-spin-spiral structure due to increasing electron hopping rates associated with double exchange. Moreover, a large negative magnetocapacitance is observed at the freezing temperature for x = 0.05, which originates from suppression of the relaxor state and thus represents a new mechanism of magnetocapacitance.

Mufti, N.; Blake, G. R.; Nugroho, A. A.; Palstra, T. T. M.

2009-11-01

191

Sidewall oxide effects on spin-torque- and magnetic-field-induced reversal characteristics of thin-film nanomagnets  

NASA Astrophysics Data System (ADS)

The successful operation of spin-based data storage devices depends on thermally stable magnetic bits. At the same time, the data-processing speeds required by today's technology necessitate ultrafast switching in storage devices. Achieving both thermal stability and fast switching requires controlling the effective damping in magnetic nanoparticles. By carrying out a surface chemical analysis, we show that through exposure to ambient oxygen during processing, a nanomagnet can develop an antiferromagnetic sidewall oxide layer that has detrimental effects, which include a reduction in the thermal stability at room temperature and anomalously high magnetic damping at low temperatures. The in situ deposition of a thin Al metal layer, oxidized to completion in air, greatly reduces or eliminates these problems. This implies that the effective damping and the thermal stability of a nanomagnet can be tuned, leading to a variety of potential applications in spintronic devices such as spin-torque oscillators and patterned media.

Ozatay, O.; Gowtham, P. G.; Tan, K. W.; Read, J. C.; Mkhoyan, K. A.; Thomas, M. G.; Fuchs, G. D.; Braganca, P. M.; Ryan, E. M.; Thadani, K. V.; Silcox, J.; Ralph, D. C.; Buhrman, R. A.

2008-07-01

192

Modulated spin structure responsible for the magnetic-field-induced polarization switching in multiferroic TbMn2O5  

NASA Astrophysics Data System (ADS)

Orthorhombic TbMn2O5 (o -TMO ) is a well-known multiferroic manganite with the remarkable property of polarization switching at 3 K under a bias magnetic (H) field along the a axis of P b 21m . To theoretically account for this outstanding observation, we have proposed a modulated spin structure under the saturated bias H field by considering the relative strength of the three relevant exchange parameters in o -TMO . The proposed modulated structure based on density-functional theory (DFT) calculations is described in terms of the spin angle ? between the neighboring M n4 +-Mn3 + spin moments on the a-b plane. We have shown that the computed DFT polarization plotted as a function of ? satisfactorily accounts for the observed H -field-induced polarization switching. We have further theoretically shown that the square of the critical field strength (Hc) needed for the polarization switching is inversely proportional to the degree of the extrinsic magnetoelectric coupling. The computed partial charge density demonstrates that the H -field-induced polarization switching also accompanies with the switching in the sign of the excess valence-electron density.

Lee, Jung-Hoon; Jang, Hyun Myung

2015-01-01

193

A dislocation model for the magnetic field induced shape memory effect in Ni2MnGa  

E-print Network

.J. Ferreira * The University of Texas at Austin, Materials Science and Engineering Program, Austin, TX 78712.06.003 * Corresponding author. Tel.: +1 512 471 3244; fax: +1 512 471 7681. E-mail address: ferreira@mail.utexas.edu (P.J. Ferreira). www.actamat-journals.com Scripta Materialia 53 (2005) 817­822 #12;Since the motion of twin

Ferreira, Paulo J.

194

Magnetic field-induced T cell receptor clustering by nanoparticles enhances T cell activation and stimulates antitumor activity.  

PubMed

Iron-dextran nanoparticles functionalized with T cell activating proteins have been used to study T cell receptor (TCR) signaling. However, nanoparticle triggering of membrane receptors is poorly understood and may be sensitive to physiologically regulated changes in TCR clustering that occur after T cell activation. Nano-aAPC bound 2-fold more TCR on activated T cells, which have clustered TCR, than on naive T cells, resulting in a lower threshold for activation. To enhance T cell activation, a magnetic field was used to drive aggregation of paramagnetic nano-aAPC, resulting in a doubling of TCR cluster size and increased T cell expansion in vitro and after adoptive transfer in vivo. T cells activated by nano-aAPC in a magnetic field inhibited growth of B16 melanoma, showing that this novel approach, using magnetic field-enhanced nano-aAPC stimulation, can generate large numbers of activated antigen-specific T cells and has clinically relevant applications for adoptive immunotherapy. PMID:24564881

Perica, Karlo; Tu, Ang; Richter, Anne; Bieler, Joan Glick; Edidin, Michael; Schneck, Jonathan P

2014-03-25

195

Pulsed Magnetic Field Induces Angiogenesis and Improves Cardiac Function of Surgically Induced Infarcted Myocardium in Sprague-Dawley Rats  

Microsoft Academic Search

Objective: It was the aim of this study to investigate the impact of pulsed magnetic field (PMF) on ischemic myocardium, though it has been reported that PMF treatment is a safe and effective method to facilitate bone and cutaneous wound healing. Methods: In this report, we describe a study in which 10 Hz 4 mT PMF and 15 Hz 6

Yuan Yuan; Liping Wei; Fei Li; Wenyi Guo; Weijie Li; Ronghua Luan; Anlin Lv; Haichang Wang

2010-01-01

196

Superconductivity, metastability and magnetic field induced phase separation in the atomic limit of the Penson-Kolb-Hubbard model  

E-print Network

We present the analysis of paramagnetic effects of magnetic field ($B$) (Zeeman term) in the zero-bandwidth limit of the extended Hubbard model for arbitrary chemical potential $\\mu$ and electron density $n$. The effective Hamiltonian considered consists of the on-site interaction $U$ and the intersite charge exchange term $I$, determining the hopping of electron pairs between nearest-neighbour sites. The model has been analyzed within the variational approach, which treats the on-site interaction term exactly and the intersite interactions within the mean-field approximation (rigorous in the limit of infinite dimensions $d\\rightarrow+\\infty$). In this report we focus on metastable phases as well as phase separated (PS) states involving superconducting (SS) and nonordered (NO) phases and determine their ranges of occurrence for $U/I_0=1.05$ ($I_0=zI$) in the presence of magnetic field $B\

Kapcia, Konrad Jerzy

2014-01-01

197

Experimental studies on ultralow frequency pulsed gradient magnetic field inducing apoptosis of cancer cell and inhibiting growth of cancer cell  

Microsoft Academic Search

The morphology characteristics of cell apoptosis of the malignant tumour cells in magnetic field-treated mouse was observed\\u000a for the first time. The apoptotic cancer cell contracted, became rounder and divorced from adjacent cells; the heterochromatin\\u000a condensed and coagulated together along the inner side of the nuclear membrane; the endoplasmic reticulums (ER) expanded and\\u000a fused with the cellular membrane; many apoptotic

Fanqing Zeng; Congyi Zheng; Xinchen Zhang; Zongshan Li; Chaoyang Li; Chuanying Wang; Xinsong Zhang; Xiaoling Huang; Husheng Zhang

2002-01-01

198

Entropy change linked to the magnetic field induced martensitic transformation in a NiMnInCo shape memory alloy  

E-print Network

ferromag- netic shape memory alloys FSMA based on Heusler com- pounds show large values of MCE­Mn­Ga alloys close to Heusler Ni2MnGa are the most studied FSMA due to their magneto- strictive behavior which in other Heusler alloys, inverse MCE when application of a magnetic field adiabatically causes the sample

199

Quantitative photoacoustic depth profilometry of magnetic field-induced thermal diffusivity inhomogeneity in the liquid crystal octylcyanobiphenyl  

E-print Network

of thermal diffusivity decreases extending to 20-30 pm below the liquid crystal surface. These decaying depth, the measurement of static and dy- namic thermal quantities in liquid crystals has been .an important venue-*0 namely the thermal diffusivity, heat capacity, and thermal conductivity, especially across the region

Mandelis, Andreas

200

Soil Orders  

NSDL National Science Digital Library

Developed by the US Department of Agriculture's Soil Survey Division (SSD), here is a high resolution poster with brief descriptions of the soil orders. Photos of soil profiles accompany descriptions of each order. The soil orders include: Alfisols, Andisols, Aridisols, Entisols, Gelisols, Histosols, Inceptisols, Mollisols, Oxisols, Spodusols, Ultisols, and Vertisols.

201

Order Up  

ERIC Educational Resources Information Center

Change orders. The words can turn the stomachs of administrators. Horror stories about change orders create fear and distrust among school officials, designers and builders. Can change orders be avoided? If car manufacturers can produce millions of intricately designed vehicles, why can't the same quality control be achieved on a construction…

Gibeault, Michael

2005-01-01

202

Presidential Orders Executive Order 31  

E-print Network

1 Presidential Orders Executive Order 31 Non-discrimination and Affirmative Action 1. Non. As permitted by applicable law, the University will take affirmative action to ensure equality of opportunity

Yetisgen-Yildiz, Meliha

203

Order Nidovirales  

Technology Transfer Automated Retrieval System (TEKTRAN)

This chapter, entitled "Order Nidovirales", is for inclusion in the Ninth Report of the International Committee on Taxonomy of Viruses (ICTV), to be published as both a single volume text and online. The chapter details the taxonomy of members of the Nidovirus order, including family Arteriviridae o...

204

Ordering Game  

NSDL National Science Digital Library

This interactive game gives students practice in ordering sets of whole numbers, integers, fractions, decimals, and the sizes of circles. Students re-order a group of numbers or objects in a line from least to greatest by dragging them. The activity is timed and points are awarded.

2011-01-01

205

Experimental evidence for an optical interference model for vibrational sum frequency generation on multilayer organic thin film systems. II. Consideration for higher order terms  

NASA Astrophysics Data System (ADS)

The generalized optical interference model for interfacial contributions to vibrational sum frequency generation (VSFG) spectroscopic signals from organic thin film systems is extended to include a description of optical interferences contained in the thin film bulk response. This is based on electric quadrupolar interactions with the input fields and includes a discussion on possible contribution from the electric quadrupolar polarization. VSFG data from the first of this two part report are analyzed and include effects from higher order responses, for both bulk and higher order interfacial terms. The results indicate that although it is capable of capturing many of the data features, the electric dipole treatment is likely not a complete description of the VSFG intensity data from this system. An analysis based on the signs of the resulting response amplitudes is used to deduce the relative magnitude of the electric dipole and higher order interfacial terms. It is found that the buried interface is closer to satisfying the electric dipole approximation, consistent with smaller field gradients due to closer index matching between the organic thin film and substrate relative to air. The procedure outlined in this work allows for the difficult task of deducing a physical picture of average molecular orientation at the buried interface of a multilayer organic thin film system while including higher order effects.

O'Brien, Daniel B.; Massari, Aaron M.

2015-01-01

206

Spin-orbit coupling in octamers in the spinel sulfide CuIr2S4: Competition between spin-singlet and quadrupolar states and its relevance to remnant paramagnetism  

NASA Astrophysics Data System (ADS)

We theoretically investigate magnetic properties in the low-temperature phase with the formation of eight-site clusters, octamers, in the spinel compound CuIr2S4. The octamer state was considered to be a spin-singlet state induced by a Peierls instability through the strong anisotropy of d orbitals, the so-called orbital Peierls state. We reexamine this picture by taking into account the spin-orbit coupling, which was ignored in the previous study. We derive a low-energy effective model between jeff=1/2 quasispins on Ir4+ cations in an octamer from the multiorbital Hubbard model with the strong spin-orbit coupling by performing the perturbation expansion from the strong correlation limit. The effective Hamiltonian is in the form of the Kitaev-Heisenberg model but with an additional interaction, a symmetric off-diagonal exchange interaction originating from the perturbation process including both d-d and d-p-d hoppings. Analyzing the effective Hamiltonian on two sites and the octamer by the exact diagonalization, we find that there is competition between a spin-singlet state and a quadrupolar state. The former singlet state is a conventional one, adiabatically connected to the orbital Peierls state. On the other hand, the latter quadrupolar state is stabilized by the additional interaction, which consists of a linear combination of different total spin momenta along the spin quantization axis. In the competing region, the model exhibits paramagnetic behavior with a renormalized small effective moment at low temperature. This peculiar remnant paramagnetism is not obtained in the Kitaev-Heisenberg model without the additional interaction. Our results renew the picture of the octamer state and provide a scenario for the intrinsic paramagnetic behavior recently observed in a muon spin rotation experiment [K. M. Kojima et al., Phys. Rev. Lett. 112, 087203 (2014)]., 10.1103/PhysRevLett.112.087203

Nasu, Joji; Motome, Yukitoshi

2014-07-01

207

Possible Antiferro-Octupolar Order in Antiferromagnetic TbB2C2 Examined by Gd Substitution  

NASA Astrophysics Data System (ADS)

We have examined the effects of Gd substitution on the anomalous antiferromagnetic (AFM) properties of TbB2C2 having field-induced antiferro-quadrupolar (AFQ) ordered phases. The Gd substitution induces drastic changes in the magnetic properties. The AFM structure characteristic to TbB2C2, the anomalous increase in magnetic susceptibility below TN, and the strong preference of AFM domains disappear with the substitution of low Gd content of less than 10%. We propose a promising assumption that an antiferro-octupolar (AFO) ordering occurs at TN simultaneously with AFM ordering in TbB2C2. The fragility of anomalous properties originates in the fragility of the antiferro-octupolar interaction against the substitution of Gd3+ ions with L=0.

Matsuoka, Eiichi; Sasaki, Yuta; Usui, Daichi; Nakagawa, Masaaki; Onodera, Hideya

2006-12-01

208

Order Phasmatodea  

NSDL National Science Digital Library

Carl Moxey of Northeastern University has created this work-in-progress Web site to provide "a comprehensive archive of information on the systematics and morphology of the insects belonging to the Order Phasmatodea." Carefully designed and easy to navigate, this Web site allows users to browse a collapsible classification tree, locate information by genera or species, view descriptions of phasmatid morphology, and more. Even though only a few translations available so far, some links provided for described genera and species lead to a related German Web site. Moxey encourages users to contribute illustrations and literature citations not already included in the site.

Moxey, Carl F.

209

Hyperfine interactions in titanates: Study of orbital ordering and local magnetic properties  

SciTech Connect

Hyperfine magnetic fields induced on the nuclei of nonmagnetic ions {sup 139}La and {sup 89}Y in LaTiO{sub 3} and YTiO{sub 3}, respectively, have been microscopically calculated. The dependence of the hyperfine fields on the orbital and magnetic structures of the compounds under study has been analyzed. The comparative analysis of the calculated and known experimental data confirms the existence of the static orbital structure in lanthanum and yttrium titanates.

Agzamova, P. A., E-mail: polina_agzamova@usu.ru; Leskova, Yu. V.; Nikiforov, A. E. [Ural Federal University (Russian Federation)

2013-05-15

210

Acoustic assisted actuation of Ni-Mn-Ga ferromagnetic shape memory alloys  

E-print Network

Ferromagnetic shape memory alloys (FSMA) have been shown in recent work to exhibit large magnetic field induced strains. The material generally requires a large threshold field (of order 3-4 kOe) to initiate the strain. ...

Peterson, Bradley William

2006-01-01

211

Experimental and Theoretical Studies of NMR in PrFe4P12 —Suggestion of Antiferro-monopole Type Ordering  

NASA Astrophysics Data System (ADS)

Experiments on the NMR signal splitting of 31P are reported for the low temperature phase of PrFe4P12, whose nature has been controversial. The observed NMR signal splitting is consistent with the field-induced antiferromagnetic moment observed by the neutron diffraction. For a theoretical analysis an invariant coupling form is first derived for the hyperfine interaction between multipolar moments and the nuclear spin in the filled skutterudite structure, and then the experimental results are analyzed. Two scenarios for the order parameter are examined: One is a ?3-type antiferro-quadrupolar (AFQ) ordering. Another is an antiferro-monopole (AF-monopole) type ordering. Experimental facts, especially the field-direction dependence in the (1\\bar{1}0) plane, are most naturally explained by the latter model, suggesting the AF-monopole ordering. Both the field-direction dependence and the field-strength dependence of the NMR splitting can be consistently accounted for if low order terms in the magnetic field are taken into account. This supports applicability of expansion regarding the magnetic field based on the AF-monopole model. Experiments can be also qualitatively reproduced by the AFQ model when the field is not near the [111] direction. It is very likely that the order parameter in PrFe4P12 is the AF-monopole, although we cannot completely rule out a possibility of the ?3-type AFQ order at present.

Sakai, Osamu; Kikuchi, Jun; Shiina, Ryousuke; Sato, Hideyuki; Sugawara, Hitoshi; Takigawa, Masashi; Shiba, Hiroyuki

2007-02-01

212

MACHINE LEARNING : The Necessity of Order (is order in order ?)  

E-print Network

- 1 - MACHINE LEARNING : The Necessity of Order (is order in order ?) A. Cornuéjols Laboratoire de to facilitate learning. Yet, when machine learners exhibited sequencing effects, showing that some data sampling is intended to present ideas and directions of research that are currently studied in the machine learning

Paris-Sud XI, Université de

213

Solving the viscous hydrodynamics order by order  

E-print Network

In this paper, we propose a method of solving the viscous hydrodynamics order by order in a derivative expansion. In such method, the zero order solution is just the one of the ideal hydrodynamics. All the other higher order corrections satisfy the same first-order partial differential equations but with different inhomogeneous terms. We therefore argue that our method could be easily extended to any orders. The problem of causality and stability will be released if the gradient expansion is guaranteed. This method might be of great help to both theoretical and numerical calculations of relativistic hydrodynamics.

Jian-Hua Gao; Shi Pu

2014-09-02

214

Variable Order and Distributed Order Fractional Operators  

NASA Technical Reports Server (NTRS)

Many physical processes appear to exhibit fractional order behavior that may vary with time or space. The continuum of order in the fractional calculus allows the order of the fractional operator to be considered as a variable. This paper develops the concept of variable and distributed order fractional operators. Definitions based on the Riemann-Liouville definitions are introduced and behavior of the operators is studied. Several time domain definitions that assign different arguments to the order q in the Riemann-Liouville definition are introduced. For each of these definitions various characteristics are determined. These include: time invariance of the operator, operator initialization, physical realization, linearity, operational transforms. and memory characteristics of the defining kernels. A measure (m2) for memory retentiveness of the order history is introduced. A generalized linear argument for the order q allows the concept of "tailored" variable order fractional operators whose a, memory may be chosen for a particular application. Memory retentiveness (m2) and order dynamic behavior are investigated and applications are shown. The concept of distributed order operators where the order of the time based operator depends on an additional independent (spatial) variable is also forwarded. Several definitions and their Laplace transforms are developed, analysis methods with these operators are demonstrated, and examples shown. Finally operators of multivariable and distributed order are defined in their various applications are outlined.

Lorenzo, Carl F.; Hartley, Tom T.

2002-01-01

215

One-particle conductance of an open quasi-two-dimensional Fermi system: Evidence of the parallel-magnetic-field-induced mode reduction effect  

NASA Astrophysics Data System (ADS)

The conductance of an open quench-disordered two-dimensional (2D) electron system subject to an in-plane magnetic field is calculated within the framework of conventional Fermi liquid theory actually applied to a three-dimensional system of spinless electrons confined to a highly anisotropic (planar) near-surface potential well. Using the calculation method suggested earlier [Phys. Rev. B 71, 125112 (2005)], the magnetic field piercing a finite range of an infinitely long laterally confined system of carriers is treated (technically) as introducing the additional highly nonlocal scattering region which separates the circuit thereby modeled into three parts—the system as such and two perfect leads. The transverse quantization spectrum of the inner part of the electron waveguide thus constructed can be effectively tuned by means of the magnetic field, even though the least transverse dimension of the waveguide is small compared to the magnetic length. The initially finite (metallic) value of the conductance, which is attributed to the existence of extended modes of the transverse quantization, decreases rapidly as the magnetic field grows. This decrease is due to the mode number reduction effect produced by the magnetic field. The closing of the last current-carrying mode, which is slightly sensitive to the disorder level, is suggested as the conceivable origin of the magnetic-field-driven metal-to-insulator transition widely observed in 2D systems.

Tarasov, Yu. V.

2006-01-01

216

Absence of Magnetic-Field-Induced Effects in the Mid-infrared Transmission of La2?xSrxCuO4 Thin Films  

SciTech Connect

We report magnetotransmission measurements on a series of La{sub 2-x}Sr{sub x}CuO{sub 4} thin films. The measurements were performed in magnetic fields of 18 T, on films with doping levels of x = 0, 0.01, 0.03, 0.045, 0.06, 0.08, and 0.10. In addition, an optimally doped film (x = 0.16) was studied in magnetic fields up to 33 T, both above and below its superconducting critical temperature T{sub c} = 41 K. A combination of Gaussian and wavelet filtering was employed to improve the signal-to-noise ratio of the data. However, even after this procedure, we could not detect any field-induced changes of transmission in any of the studied samples. Our results therefore rule out a direct relation between intensity changes in mid-infrared charge excitations and a bosonic mode in the far infrared. We discuss these observations in the context of existing proposals regarding the nature of medium energy range excitations in the cuprates.

Dordevic, S.V.; Gozar, A.; Kohlman, L.W.; Tung, L.C.; Wang, Y.-J.; Logvenov, G.; Bozovic, I.

2009-04-01

217

Magnetic-Field Induced Transition to the 1\\/2 Magnetization Plateau State in the Geometrically Frustrated Magnet CdCr2O4  

Microsoft Academic Search

The magnetization of the geometrically frustrated spinel CdCr2O4 was measured in pulsed fields of up to 47 T. We found a metamagnetic transition to a very wide magnetization plateau state with one half of the full moment of S=3\\/2 Cr3+ at 28 T, independent of the field direction. This is the first observation of magnetization plateau state realized in Heisenberg

Hiroaki Ueda; Hiroko Aruga Katori; Hiroyuki Mitamura; Tsuneaki Goto; Hidenori Takagi

2005-01-01

218

High magnetic field induced spin flip/flop behavior and magnetic phase diagram of CuFe1-xGaxO2  

NASA Astrophysics Data System (ADS)

The structure and magnetic properties of non-magnetic Ga3+ ion doped CuFe1-xGaxO2 (x=0, 0.03, and 0.05) single crystal samples were investigated. X-ray diffraction patterns analysis confirms that the samples are single-phase crystallizing. Doping effect on the magnetic behavior of the ground state and the field-induced spin flip/flop transitions were detected. The transition temperatures and critical magnetic fields of the spin flip/flop, as well as the magnetic hysteresis directly depend on the Ga3+ doping level. Such doping effects may associate with the competition between dilution effect (partial release of spin frustration) and the induced local magnetic moment, which is the result of the changed magnetic coupling both inter- and intra-planes of Fe ions. Based on the experimental results, the effects of Ga3+ doping on the spin flip/flop behavior and a detailed high field magnetic diagram were assumed.

Shi, L. R.; Xia, Z. C.; Jin, Z.; Wei, M.; Huang, J. W.; Chen, B. R.; Xiao, L. X.; Zuo, H. K.; Ouyang, Z. W.

2014-11-01

219

Neutron diffraction study of magnetic field induced behavior in the heavy Fermion Ce3Co4Sn13  

SciTech Connect

The specific heat of Ce3Co4Sn13 exhibits a crossover from heavy Fermion behavior with antiferromagnetic correlations at low field to single impurity Kondo behavior above 2 T. We have performed neutron diffraction measurements in magnetic fields up to 6 Tesla on single crystal samples. The (001) position shows a dramatic increase in intensity in field which appears to arise from static polarization of the 4f level and which at 0.14 K also exhibits an anomaly near 2T reflecting the crossover to single impurity behavior.

Christianson, Andrew D [ORNL; Goremychkin, E. A. [ISIS Facility, Rutherford Appleton Laboratory; Gardner, J. S. [Indiana University; Kang, H. J. [National Institute of Standards and Technology (NIST); Chung, J.-H. [National Institute of Standards and Technology (NIST); Manuel, P. [ISIS Facility, Rutherford Appleton Laboratory; Thompson, J. D. [Los Alamos National Laboratory (LANL); Sarrao, J. L. [Los Alamos National Laboratory (LANL); Lawrence, J. M. [University of California, Irvine

2008-01-01

220

Microwave Spectroscopy Evidence of Superconducting Pairing in the Magnetic-Field-Induced Metallic State of InOx Films at Zero Temperature  

NASA Astrophysics Data System (ADS)

We investigate the field-tuned quantum phase transition in a 2D low-disorder amorphous InOx film in the frequency range of 0.05 to 16 GHz employing microwave spectroscopy. In the zero-temperature limit, the ac data are consistent with a scenario where this transition is from a superconductor to a metal instead of a direct transition to an insulator. The intervening metallic phase is unusual with a small but finite resistance that is much smaller than the normal state sheet resistance at the lowest measured temperatures. Moreover, it exhibits a superconducting response on short length and time scales while global superconductivity is destroyed. We present evidence that the true quantum critical point of this 2D superconductor metal transition is located at a field Bsm far below the conventionally defined critical field Bcross where different isotherms of magnetoresistance cross each other. The superfluid stiffness in the low-frequency limit and the superconducting fluctuation frequency from opposite sides of the transition both vanish at B?Bsm. The lack of evidence for finite-frequency superfluid stiffness surviving Bcross signifies that Bcross is a crossover above which superconducting fluctuations make a vanishing contribution to dc and ac measurements.

Liu, Wei; Pan, LiDong; Wen, Jiajia; Kim, Minsoo; Sambandamurthy, G.; Armitage, N. P.

2013-08-01

221

Large remnant polarization and magnetic field induced destruction of cycloidal spin structure in Bi1-xLaxFeO3 (0 ? x ? 0.2)  

NASA Astrophysics Data System (ADS)

We prepared a series of Bi1-xLaxFeO3 (0 ? x ? 0.2) ceramics with a sol-gel method and find that both the magnetization and dielectric constant show an abrupt anomaly near a critical field Hc, which is attributed to the destruction of the cycloidal antiferromagnetic spin structure. The critical field Hc decreases substantially from ˜20 T for the x = 0 sample [Y. F. Popov et al., JETP Lett. 57, 69 (1993)] to ˜2.8 T for the x = 0.17 sample and finally to 0 T for the x = 0.2 sample at room temperature (RT). It is also found that Hc increases with decreasing temperature. The variation of Hc with La substitution and temperature can be ascribed to the change in the magnetic anisotropy and isotropic superexchange interaction, respectively. We have also discussed the magnetodielectric effects in these samples in terms of the Ginzburg-Landau theory and the spin-phonon model. Moreover, increasing the doping level of La to 0.15 greatly improves the RT leakage-current and ferroelectric (FE) properties. A RT square-shaped FE hysteresis loop with remnant polarization (2Pr) as high as ˜64 ?C/cm2 is obtained for the x = 0.15 sample. These results may be important for potential applications in BiFeO3-based magnetoelectric devices.

Yin, L. H.; Yang, J.; Zhao, B. C.; Liu, Y.; Tan, S. G.; Tang, X. W.; Dai, J. M.; Song, W. H.; Sun, Y. P.

2013-06-01

222

Spin dynamics in a diluted magnetic semiconductor quantum well studied by pump-probe absorption spectroscopy: Magnetic-field-induced suppression of electron-spin relaxation  

Microsoft Academic Search

Exciton spin dynamics is studied in a diluted magnetic semiconductor quantum well of Cd0.95Mn0.05Te by pump-probe absorption spectroscopy under magnetic fields. The time dependences of the saturated absorbance for the higher- and lower-energy spin states of heavy-hole (hh) excitons clarify the following exciton-spin relaxation process in magnetic fields: ultrafast hh-spin relaxation with the formation of dark excitons and subsequent electron-spin

A. Murayama; K. Seo; K. Nishibayashi; I. Souma; Y. Oka

2006-01-01

223

Magnetic field induced percolation in Pr0.67Ca0.33MnO3 by small angle magnetic neutron scattering  

NASA Astrophysics Data System (ADS)

We have studied by small angle neutron scattering the evolution induced by the application of magnetic field of the coexistence of ferromagnetism and antiferromagnetism in a crystal of Pr0.67Ca0.33MnO3. The results are compared to magnetic measurements, which provide the evolution of the ferromagnetic fraction. These results show that the growth of the ferromagnetic phase corresponds to an increase of the thickness of the ferromagnetic ``cabbage'' sheets.

Simon, Ch.; Mercone, S.; Hardy, V.; Martin, C.; Saurel, D.; Brulet, A.

2004-05-01

224

Magnetic field-induced shift of the optical band gap in Ni3V2O8 B. S. Holinsworth,1  

E-print Network

-induced blue shifts of the band gap that are much larger than that of the Zeeman effect in isolation properties. This effect can be as simple as the textbook case of Zeeman splitting of an isolated atom10-induced changes in the optical properties requires reaching beyond traditional mechanisms like the Zeeman effect

225

PHYSICAL REVIEW B 89, 165120 (2014) Magnetic-field-induced shift of the optical band gap in Ni3V2O8  

E-print Network

reveal field-induced blue shifts of the band gap that are much larger than that of the Zeeman effect in the optical properties requires reaching beyond traditional mechanisms like the Zeeman effect to include]. The magnetic field also drives changes in the electronic properties. This effect can be as simple

226

Acyl chain orientational order in large unilamellar vesicles: comparison with multilamellar liposomes: a 2H and 31P nuclear magnetic resonance study.  

PubMed Central

Large unilamellar vesicles (LUVs) composed of 1-[2H31]palmitoyl-2-oleoyl phosphatidylcholine (POPC-d31), with diameters of approximately 117 +/- 31 and 180 +/- 44 nm, were prepared by extrusion through polycarbonate filters with pore sizes of 0.1 and 0.2 microns, respectively. The 2H nuclear magnetic resonance (NMR) spectra obtained at 21 degrees C contain two components: a broad component (approximately 17 kHz linewidth) corresponding to the methylene groups and a narrower component originating from the methyl groups. Spectra with increasing powder pattern characteristics were obtained by reducing the rate of phospholipid reorientations by addition of glycerol (to increase the solvent viscosity) and by lowering the temperature. Full powder spectra, characteristic of liquid-crystalline bilayers, were obtained for both LUV samples at 0 degrees C in the presence of 50 wt% glycerol. Individual quadrupolar splittings were not resolved in these spectra, due to broader linewidths in the LUVs, which have significantly shorter values for spin-spin relaxation time T2 measured from the decay of the quadrupolar echo (90 microseconds) than the multilmellar vesicles (MLVs; 540 microseconds). Smoothed order parameter profiles (OPPs) were obtained for these samples by integration of the dePaked spectra. The OPPs were very similar to the OPP of POPC-d31 MLVs in 50 wt% glycerol at the same temperature, indicating that orientational order in MLVs and LUVs with a diameter of > or = 100 nm is essentially the same. The presence of 80 wt% glycerol was found to have a disordering effect on the vesicles. PMID:8324185

Fenske, D B; Cullis, P R

1993-01-01

227

Dispensation Order Generation for  

E-print Network

Dispensation Order Generation for Pyrosequencing Mats Carlsson and Nicolas Beldiceanu Dispensation Institute of Computer Science (SICS) September 20, 2004 #12;Dispensation Order Generation for Pyrosequencing Mats Carlsson and Nicolas Beldiceanu Part I Table of Contents #12;Dispensation Order Generation

228

December 2010 ORDERING CHEMICALS  

E-print Network

December 2010 ORDERING CHEMICALS Order your chemicals through SunRISE. This is the fastest, most accurate method to order chemicals, and SunRISE offers University Stockroom for ordering solvents to obtain the best price. If a chemical is not in Sun

Rhoads, James

229

Contribution of higher order plasmonic modes on optical absorption enhancement in amorphous silicon thin films  

NASA Astrophysics Data System (ADS)

For an array of regularly patterned interacting spherical Ag nano particles over an amorphous silicon (a-Si:H) layer of thickness 200 nm, we use Finite Difference Time Domain method for studying the plasmonic absorption enhancement within the a-Si:H layer over the visible range (400 nm-750 nm). The nano particle radius (R) has been varied from 100 nm to 200 nm and array period (D) from 320 nm to 500 nm satisfying the criteria 2Rorder plasmonic modes (mainly quadrupolar and octupolar) have significant contribution to the absorption enhancement within the a-Si:H layer. The role of the spectral overlap between different plasmonic modes has been described in controlling the absorption spectra for various configurations of R and D. It has been shown that a broad spectral absorption enhancement within the visible spectrum may be possible for a wide range of D variation from 320 nm to 500 nm using array of nano particles having R=140 nm. On the other hand, choosing a surface coverage factor of 19%, enhanced absorption within narrow wavelengths bands has been observed. The position of these narrow bands may be tuned by suitable choice of nano particle size. We propose these findings to proffer promising applications in solar cells as also in visible range photo detectors.

Mandal, Aparajita; Chaudhuri, Partha

2013-07-01

230

Order Statistic Experiment  

NSDL National Science Digital Library

This resource consists of a Java applet and expository text. The applet simulates the order statistics of a random sample from a given distribution. The sample size, order, and sampling distribution can be specified.

Siegrist, Kyle

231

First-order inflation  

NASA Technical Reports Server (NTRS)

In the original proposal, inflation occurred in the process of a strongly first-order phase transition. This model was soon demonstrated to be fatally flawed. Subsequent models for inflation involved phase transitions that were second-order, or perhaps weakly first-order; some even involved no phase transition at all. Recently the possibility of inflation during a strongly first-order phase transition has been revived. In this talk I will discuss some models for first-order inflation, and emphasize unique signatures that result if inflation is realized in a first-order transition. Before discussing first-order inflation, I will briefly review some of the history of inflation to demonstrate how first-order inflation differs from other models.

Kolb, Edward W.

1991-01-01

232

Order of Operations  

NSDL National Science Digital Library

Students will learn order of operations. PEMDAS will become a helpful acronym for successfully mastering order of operations. Students will learn the importance of solving problems using order of operations. An acronym will be introduced that will help them remember the order of operations. Interactive guidance and practice will be available for students to access. This tutorial will include the following learning modules: 1) motivation and ...

Nieman, Mrs.

2008-10-05

233

First Order ODEs Introduction  

E-print Network

first-order ordinary differential equations. It is so-called because we rearrange the equation. Then you will learn how to recognise when a first-order differential equation is an exact equation and how to solve an exact equation. An exact first-order differential equation is one which can be solved by simply

Vickers, James

234

Multiple ordering in magnetite.  

NASA Technical Reports Server (NTRS)

Results of a self-consistent band calculation of the ground-state energy and charge orderings based on a tight-binding scheme in magnetite are presented. They show that below a critical (about 2.2) value of the ratio of interatomic Coulomb energy to bandwidth the lowest energy state has no order. Between this critical value and 2.5, the preferred state is multiply ordered.

Cullen, J. R.; Callen, E. R.

1973-01-01

235

Exploring Order of Operations  

NSDL National Science Digital Library

This interactive activity demonstrates the order of operations. The game asks students to click on the correct operation in a series of mathematical problems. Correct answers will increase the user's time for the next game. Students should have some knowledge of the order of operations prior to doing this activity. Two worksheets are also available for print or download in PDF file format.

2012-08-06

236

Finite Order Statistic Experiment  

NSDL National Science Digital Library

This resource consists of a Java applet and expository text. The applet is a simulation of the experiment of selecting n objects at random from the first m positive integers. The random variables of interest are the order statistics. The applet illustrates the distributions of the order statistics.

Siegrist, Kyle

237

ASDC Order Tools  

... users to search our data holdings without logging in to the system. The user, however, must log in before ordering the data. ... Reverb, developed by Earth Science Data and Information System (ESDIS), gives the user community an improved search and order ...

2012-04-17

238

Higher order fractional derivatives  

E-print Network

Based on the Liouville-Weyl definition of the fractional derivative, a new direct fractional generalization of higher order derivatives is presented. It is shown, that the Riesz and Feller derivatives are special cases of this approach.

Richard Herrmann

2009-06-12

239

Programming Languages: Marching Orders  

NSDL National Science Digital Library

In this activity about computer programming, learners follow instructions in a variety of ways in order to successfully draw figures. Through these exercises, learners will experience some of the often frustrating aspects of computer programming.

Bell, Tim; Witten, Ian; Fellows, Mike; Adams, Robyn; Mckenzie, Jane

2005-01-01

240

Ordered Simple Plot  

NSDL National Science Digital Library

This interactive Java applet allows users to plot ordered pairs on the Cartesian coordinate plane. The applet plots the points in the order they are entered. By selecting the option Plot Type: Connected, the user can create shapes. Other options include entering multiple data sets for comparison, changing the dimensions of the x- and y-axes, zoom and pan features, and grid line display.

2008-01-01

241

Land and World Order.  

ERIC Educational Resources Information Center

The papers in this publication discuss the land and how what happens to the land affects us. The publication is one in a series of monographs that examine the linkages between local and global concerns and explore alternative world futures. Examples of topics discussed in the papers follow. The paper "Land and World Order" examines implications of…

Mische, Patricia, Ed.; And Others

1982-01-01

242

Order: Homoptera Family: Aphididae  

E-print Network

Order: Homoptera Family: Aphididae DESCRIPTION Aphids, or plant lice, are small, soft-bodied insects. There are hundreds of different species of aphids, some of which attack only one host plant while others attack numerous hosts. Most aphids are about 1/10 inch long (2.54 mm), and though green and black

Liskiewicz, Maciej

243

Operation Order Algebra Game  

NSDL National Science Digital Library

This interactive game reinforces the importance of the order of operations within equations. Players enter the three numbers on the rocks in the correct box to make a true closed equation. A check answer button provides feedback and there are three levels of difficulty to provide challenge at the student's skill level.

2012-01-01

244

Fractional order junctions  

NASA Astrophysics Data System (ADS)

Gottfried Leibniz generalized the derivation and integration, extending the operators from integer up to real, or even complex, orders. It is presently recognized that the resulting models capture long term memory effects difficult to describe by classical tools. Leon Chua generalized the set of lumped electrical elements that provide the building blocks in mathematical models. His proposal of the memristor and of higher order elements broadened the scope of variables and relationships embedded in the development of models. This paper follows the two directions and proposes a new logical step, by generalizing the concept of junction. Classical junctions interconnect system elements using simple algebraic restrictions. Nevertheless, this simplistic approach may be misleading in the presence of unexpected dynamical phenomena and requires including additional “parasitic” elements. The novel ?-junction includes, as special cases, the standard series and parallel connections and allows a new degree of freedom when building models. The proposal motivates the search for experimental and real world manifestations of the abstract conjectures.

Machado, J. Tenreiro

2015-01-01

245

Stochastically ordered multiple regression  

PubMed Central

In various application areas, prior information is available about the direction of the effects of multiple predictors on the conditional response distribution. For example, in epidemiology studies of potentially adverse exposures and continuous health responses, one can typically assume a priori that increasing the level of an exposure does not lead to an improvement in the health response. Such an assumption can be formalized through a stochastic ordering assumption in each of the exposures, leading to a potentially large improvement in efficiency in nonparametric modeling of the conditional response distribution. This article proposes a Bayesian nonparametric approach to this problem based on characterizing the conditional response density as a Gaussian mixture, with the locations of the Gaussian means varying flexibly with predictors subject to minimal constraints to ensure stochastic ordering. Theoretical properties are considered and Markov chain Monte Carlo methods are developed for posterior computation. The methods are illustrated using simulation examples and a reproductive epidemiology application. PMID:20150656

Bornkamp, Björn; Ickstadt, Katja; Dunson, David

2010-01-01

246

Mail Order Food Safety  

MedlinePLUS

... Administrative Forms Standard Forms Skip Navigation Z7_0Q0619C0JGR010IFST1G5B10H1 Web Content Viewer (JSR 286) Actions ${title} Loading... / Topics / ... Food Handling / Mail Order Food Safety Z7_0Q0619C0JGR010IFST1G5B10H3 Web Content Viewer (JSR 286) Actions ${title} Loading... Z7_ ...

247

Audiotactile temporal order judgments.  

PubMed

We report a series of three experiments in which participants made unspeeded 'Which modality came first?' temporal order judgments (TOJs) to pairs of auditory and tactile stimuli presented at varying stimulus onset asynchronies (SOAs) using the method of constant stimuli. The stimuli were presented from either the same or different locations in order to explore the potential effect of redundant spatial information on audiotactile temporal perception. In Experiment 1, the auditory and tactile stimuli had to be separated by nearly 80 ms for inexperienced participants to be able to judge their temporal order accurately (i.e., for the just noticeable difference (JND) to be achieved), no matter whether the stimuli were presented from the same or different spatial positions. More experienced psychophysical observers (Experiment 2) also failed to show any effect of relative spatial position on audiotactile TOJ performance, despite having much lower JNDs (40 ms) overall. A similar pattern of results was found in Experiment 3 when silent electrocutaneous stimulation was used rather than vibrotactile stimulation. Thus, relative spatial position seems to be a less important factor in determining performance for audiotactile TOJ than for other modality pairings (e.g., audiovisual and visuotactile). PMID:15698825

Zampini, Massimiliano; Brown, Timothy; Shore, David I; Maravita, Angelo; Röder, Brigitte; Spence, Charles

2005-03-01

248

The Yb2Al1-xMgxSi2 series from a spin fluctuation (x = 0) to a magnetically ordered ground state (x = 1)  

NASA Astrophysics Data System (ADS)

The structural and magnetic properties of Yb2Al1-xMgxSi2 (x = 0, 0.5 and 1), crystallizing in the tetragonal Mo2FeB2-type structure, are reported in this work. Yb2AlSi2 exhibits a Pauli paramagnetic ground state arising due to spin/valence fluctuations induced by a significant Yb 4f conduction band hybridization. High-field magnetization (up to 120 kOe) indicates a nearly temperature-independent susceptibility of 8.6 × 10-3 emu/Yb mol below 10 K. On the other hand, Yb ions in Yb2MgSi2 order antiferromagnetically at a relatively high temperature TN of 9.5 K. The intermediate composition alloy Yb2Al0.5Mg0.5Si2 is a Kondo lattice, antiferromagnet with TN = 5.5 K. The coefficient of the linear term of the electronic heat capacity, ?, of Yb2AlSi2 is found to be 305 mJ mol-1 K-2, indicating a significant electronic mass enhancement due to strong electronic correlations. Below 12 K, an additional contribution to the heat capacity of the form T3lnT is observed. The 170Yb Mössbauer spectra in the ordered state of Yb2MgSi2 indicate a strong coupling of the 4f quadrupolar moment with the magnetic moment through a magneto-elastic coupling.

Shah, K. V.; Bonville, P.; Manfrinetti, P.; Wrubl, F.; Dhar, S. K.

2009-04-01

249

1.NBT Ordering Numbers  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Malik is given a list of numbers: 1 \\ \\ 5 \\ \\ 10 \\ \\ 50 \\ \\ 100 He wants to include the following numbers so all numbers will be listed in order from l...

2012-05-01

250

Higher-Order Containers  

NASA Astrophysics Data System (ADS)

Containers are a semantic way to talk about strictly positive types. In previous work it was shown that containers are closed under various constructions including products, coproducts, initial algebras and terminal coalgebras. In the present paper we show that, surprisingly, the category of containers is cartesian closed, giving rise to a full cartesian closed subcategory of endofunctors. The result has interesting applications in generic programming and representation of higher order abstract syntax. We also show that the category of containers has finite limits, but it is not locally cartesian closed.

Altenkirch, Thorsten; Levy, Paul; Staton, Sam

251

Birth order and myopia  

PubMed Central

Purpose An association between birth order and reduced unaided vision (a surrogate for myopia) has been observed previously. We examined the association between birth order and myopia directly in 4 subject groups. Methods Subject groups were participants in 1) the Avon Longitudinal Study of Parents and Children (ALSPAC; UK; age 15 years; N=4,401), 2) the Singapore Cohort Study of Risk Factors for Myopia (SCORM; Singapore; age 13 years; N=1,959), 3) the Raine Eye Health Study (REHS; Australia; age 20 years; N=1,344), and 4) Israeli Defense Force recruitment candidates (IDFC; Israel; age 16-22 years; N=888,277). Main outcome: Odds ratio (OR) for myopia in first born versus non-first born individuals after adjusting for potential risk factors. Results The prevalence of myopia was numerically higher in first-born versus non-first-born individuals in all study groups, but the strength of evidence varied widely. The adjusted ORs (95% CI) were: ALSPAC, 1.31 (1.05-1.64); SCORM, 1.25 (0.89-1.77); REHS, 1.18 (0.90-1.55); IDFC, 1.04 (1.03-1.06). In the large IDFC sample, the effect size was greater (a) for the first born versus fourth or higher born comparison than for the first born versus second/third born comparison (P<0.001) and (b) with increasing myopia severity (P<0.001). Conclusions Across all studies, the increased risk of myopia in first born individuals was low (OR <1.3). Indeed, only the studies with >4000 participants provided strong statistical support for the association. The available evidence suggested the relationship was independent of established risk factors such as time outdoors/reading, and thus may arise through a different causal mechanism. PMID:24168726

Guggenheim, Jeremy A.; McMahon, George; Northstone, Kate; Mandel, Yossi; Kaiserman, Igor; Stone, Richard A.; Lin, Xiaoyu; Saw, Seang Mei; Forward, Hannah; Mackey, David A.; Yazar, Seyhan; Young, Terri L.; Williams, Cathy

2013-01-01

252

Circle Orders, N-gon Orders Crossing Number of Partial Orders.  

E-print Network

Circle Orders, N-gon Orders and the Crossing Number of Partial Orders. J. B. SIDNEY Faculty are disks (i.e. circles together with their interiors), P(F, circle order; if the elements of F are n-polygons, P(F, circle orders and n

Urrutia, Jorge

253

Topology in Ordered Phases  

NASA Astrophysics Data System (ADS)

I. Topology as universal concept. Optical vorticulture / M. V. Berry. On universality of mathematical structure in nature: topology / T. Matsuyama. Topology in physics / R. Jackiw. Isoholonomic problem and holonomic quantum computation / S. Tanimura -- II. Topological crystals. Topological crystals of NbSe[symbol] / S. Tanda ... [et al.]. Superconducting states on a Möbius strip / M. Hayashi ... [et al.]. Structure analyses of topological crystals using synchrotron radiation / Y. Nogami ... [et al.]. Transport measurement for topological charge density waves / T. Matsuura ... [et al.]. Theoretical study on Little-Parks oscillation in nanoscale superconducting ring / T. Suzuki, M. Hayashi and H. Ebisawa. Frustrated CDW states in topological crystals / K. Kuboki ... [et al.]. Law of growth in topological crystal / M. Tsubota ... [et al.]. Synthesis and electric properties of NbS[symbol]: possibility of room temperature charge density wave devices / H. Nobukane ... [et al.]. How does a single crystal become a Möbius strip? / T. Matsuura ... [et al.]. Development of X-ray analysis method for topological crystals / K. Yamamoto ... [et al.] -- III. Topological materials. Femtosecond-timescale structure dynamics in complex materials: the case of (NbSe[symbol])[symbol]I / D. Dvorsek and D. Mihailovic. Ultrafast dynamics of charge-density-wave in topological crystals / K. Shimatake ... [et al.]. Topology in morphologies of a folded single-chain polymer / Y. Takenaka, D. Baigl and K. Yoshikawa. One to two-dimensional conversion in topological crystals / T. Toshima, K. Inagaki and S. Tanda. Topological change of Fermi surface in Bismuth under high pressure / M. Kasami ... [et al.]. Topological change of 4, 4'-bis[9-dicarbazolyl]-2, 2'-biphenyl (CBP) by international rearrangement / K. S. Son ... [et al.]. Spin dynamics in Heisenberg triangular system VI5 cluster studied by [symbol]H-NMR / Y. Furukawa ... [et al.]. STM/STS on NbSe[symbol] nanotubes / K. Ichimura ...[et al.]. Nanofibers of hydrogen storage alloy / I. Saita ... [et al.]. Synthesis of stable icosahedral quasicrystals in Zn-Sc based alloys and their magnetic properties / S. Kashimoto and T. Ishimasa. One-armed spiral wave excited by eam pressure in accretion disks in Be/X-Ray binaries / K. Hayasaki and A. T. Okazaki -- IV. Topological defects and excitations. Topological excitations in the ground state of charge density wave systems / P. Monceau. Soliton transport in nanoscale charge-density-wave systems / K. Inagaki, T. Toshima and S. Tanda. Topological defects in triplet superconductors UPt3, Sr[symbol]RuO[symbol], etc. / K. Maki ... [et al.]. Microscopic structure of vortices in type II superconductors / K. Machida ... [et al.]. Microscopic neutron investigation of the Abrikosov state of high-temperature superconductors / J. Mesot. Energy dissipation at nano-scale topological defects of high-Tc superconductors: microwave study / A. Maeda. Pressure induced topological phase transition in the heavy Fermion compound CeAl[symbol] / H. Miyagawa ... [et al.]. Explanation for the unusual orientation of LSCO square vortex lattice in terms of nodal superconductivity / M. Oda. Local electronic states in Bi[symbol]Sr[symbol]CaCu[symbol]O[symbol] / A. Hashimoto ... [et al.] -- V. Topology in quantum phenomena. Topological vortex formation in a Bose-Einstein condensate of alkali-metal atoms / M. Nakahara. Quantum phase transition of [symbol]He confined in nano-porous media / K. Shirahama, K. Yamamoto and Y. Shibayama. A new mean-field theory for Bose-Einstein condensates / T. Kita. Spin current in topological cristals / Y. Asano. Antiferromagnetic defects in non-magnetic hidden order of the heavy-electron system URu[symbol]Si[symbol] / H. Amitsuka, K. Tenya and M. Yokoyama. Magnetic-field dependences of thermodynamic quantities in the vortex state of Type-II superconductors / K. Watanabe, T. Kita and M. Arai. Three-magnon-mediated nuclear spin relaxation in quantum ferrimagnets of topological origin / H. Hori and S, Yamamoto. Topological aspects of wave function statistics at t

Tanda, Satoshi; Matsuyama, Toyoki; Oda, Migaku; Asano, Yasuhiro; Yakubo, Kousuke

2006-08-01

254

Package Order (ECC-C) 1 Package Order  

E-print Network

Package Order (ECC-C) 1 Package Order for use with framework contracts based on the NEC3 ECC: Construction and refurbishment of buildings in the Tshimologong Precinct - Braamfontein Package Order No: 1 Title of Work Package: Tshimologong Precinct - Phase 1 Contract Data associated with a Work Package Part

Wagner, Stephan

255

7 CFR 1280.113 - Order.  

Code of Federal Regulations, 2010 CFR

...SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE LAMB PROMOTION, RESEARCH, AND INFORMATION ORDER Lamb Promotion, Research, and Information Order Definitions § 1280.113 Order. Order...

2010-01-01

256

Insertion Order Virginia Tech Magazine  

E-print Network

Insertion Order Virginia Tech Magazine This Insertion Order constitutes an agreement between Virginia Polytechnic Institute and State University (Virginia Tech) and ___________________________ (Client) for advertising space in Virginia Tech Magazine, published by Virginia Tech. Edition(s): Summer 2014 Fall 2014

Buehrer, R. Michael

257

Collegiate Order No. Collegiate Apparel  

E-print Network

Time To Call Email address ( ) Individual Street Address City County State Zip Office Phone Best Time ...........................................................$. __________ CREDIT CARD OR PURCHASE ORDER VISA Mastercard Discover Credit Card No _______________________________________________ Name exactly as it appears on card Purchase Order #____________________________________________ OFFICE

258

Lepidosauria I. Tuataras (Order Rhynochephalia)  

E-print Network

1 Lepidosauria I. Tuataras (Order Rhynochephalia) II. Order Squamata, phylogeny III. Lizard Have acrodont teeth. Draco Moloch horridus Agama III. Lizard Families ~44 native California lizard species Phrynocephalus -defensive posture -live bearing: Viviparous Frill-necked Lizard (Chlamydosaurus

Dever, Jennifer A.

259

NCI Mouse Repository - Ordering Information  

Cancer.gov

STRAIN UNAVAILABLE FOR ORDERING The LPV-TAg, T121, LST1137, dl1137 strain is currently unavailable for ordering. Top of Page | NCI Mouse Repository | Emice Website | Privacy | Disclaimer Available Strains | Newly Accepted Strains | General Info & Help

260

NCI Mouse Repository - Ordering Information  

Cancer.gov

We have had a number of problems with orders and material transfer agreements (MTAs), so we have prepared instructions to shorten the time for processing orders. The MTA is a legal document. Therefore, please read these instructions completely before placing your order.

261

The Greenbergian Word Order Correlations.  

ERIC Educational Resources Information Center

An empirical study of word order correlations, based on a sample of 625 languages, determined exactly what pairs of elements correlate in order with the verb and object. An alternative to the Head-Dependent Theory is presented: the Branching Direction Theory, based on consistent ordering of phrasal and nonphrasal elements. (85 references)…

Dryer, Matthew S.

1992-01-01

262

Large remnant polarization and magnetic field induced destruction of cycloidal spin structure in Bi{sub 1-x}La{sub x}FeO{sub 3} (0 {<=} x {<=} 0.2)  

SciTech Connect

We prepared a series of Bi{sub 1-x}La{sub x}FeO{sub 3} (0 {<=} x {<=} 0.2) ceramics with a sol-gel method and find that both the magnetization and dielectric constant show an abrupt anomaly near a critical field H{sub c}, which is attributed to the destruction of the cycloidal antiferromagnetic spin structure. The critical field H{sub c} decreases substantially from {approx}20 T for the x = 0 sample [Y. F. Popov et al., JETP Lett. 57, 69 (1993)] to {approx}2.8 T for the x = 0.17 sample and finally to 0 T for the x = 0.2 sample at room temperature (RT). It is also found that H{sub c} increases with decreasing temperature. The variation of H{sub c} with La substitution and temperature can be ascribed to the change in the magnetic anisotropy and isotropic superexchange interaction, respectively. We have also discussed the magnetodielectric effects in these samples in terms of the Ginzburg-Landau theory and the spin-phonon model. Moreover, increasing the doping level of La to 0.15 greatly improves the RT leakage-current and ferroelectric (FE) properties. A RT square-shaped FE hysteresis loop with remnant polarization (2P{sub r}) as high as {approx}64 {mu}C/cm{sup 2} is obtained for the x = 0.15 sample. These results may be important for potential applications in BiFeO{sub 3}-based magnetoelectric devices.

Yin, L. H.; Yang, J.; Zhao, B. C.; Liu, Y.; Tan, S. G.; Tang, X. W.; Dai, J. M.; Song, W. H. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031, People's Republic of China (China)] [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031, People's Republic of China (China); Sun, Y. P. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031, People's Republic of China (China) [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031, People's Republic of China (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, People's Republic of China (China)

2013-06-07

263

Counterbalancing for Serial Order Carryover Effects in Experimental Condition Orders  

ERIC Educational Resources Information Center

Reactions of neural, psychological, and social systems are rarely, if ever, independent of previous inputs and states. The potential for serial order carryover effects from one condition to the next in a sequence of experimental trials makes counterbalancing of condition order an essential part of experimental design. Here, a method is proposed…

Brooks, Joseph L.

2012-01-01

264

SECOND-ORDER ELASTICITY AND FIRST-ORDER FREDERIKS TRANSITIONS  

E-print Network

SECOND-ORDER ELASTICITY AND FIRST-ORDER FREDERIKS TRANSITIONS IN NEMATIC LIQUID CRYSTALS H. P by Deuling and Hel- frich [5] for homeotropic nematic liquid crystal layers with a large anisotropic.aid of the surface anchoring energy. 1. Introduction. -- The static deformations in nematic liquid layers with Rapini

Boyer, Edmond

265

Ordering variable for parton showers  

NASA Astrophysics Data System (ADS)

The parton splittings in a parton shower are ordered according to an ordering variable, for example the transverse momentum of the daughter partons relative to the direction of the mother, the virtuality of the splitting, or the angle between the daughter partons. We analyze the choice of the ordering variable and conclude that one particular choice has the advantage of factoring softer splittings from harder splittings graph by graph in a physical gauge.

Nagy, Zoltán; Soper, Davison E.

2014-06-01

266

Helicity order: hidden order parameter in URu2Si2.  

PubMed

We propose that the "hidden order parameter" in URu2Si2 is a helicity order that must arise if the Pomeranchuk criteria for the spin-antisymmetric Landau parameters with respect to the stability of a Fermi liquid state are violated. In a simple model, we calculate the specific heat, the linear and nonlinear magnetic susceptibilities, and the change of transition temperature in a magnetic field with such an order parameter, and obtain quantitative agreement with experiments in terms of two parameters extracted from the data. The peculiar temperature dependence of the NMR linewidth and the nature of the loss of excitations in the ordered phase seen by neutron scattering are also explained, and experiments are suggested to directly confirm the proposed order parameter. PMID:16486745

Varma, C M; Zhu, Lijun

2006-01-27

267

Hierarchical Ordering of Reticular Networks  

PubMed Central

The structure of hierarchical networks in biological and physical systems has long been characterized using the Horton-Strahler ordering scheme. The scheme assigns an integer order to each edge in the network based on the topology of branching such that the order increases from distal parts of the network (e.g., mountain streams or capillaries) to the “root” of the network (e.g., the river outlet or the aorta). However, Horton-Strahler ordering cannot be applied to networks with loops because they they create a contradiction in the edge ordering in terms of which edge precedes another in the hierarchy. Here, we present a generalization of the Horton-Strahler order to weighted planar reticular networks, where weights are assumed to correlate with the importance of network edges, e.g., weights estimated from edge widths may correlate to flow capacity. Our method assigns hierarchical levels not only to edges of the network, but also to its loops, and classifies the edges into reticular edges, which are responsible for loop formation, and tree edges. In addition, we perform a detailed and rigorous theoretical analysis of the sensitivity of the hierarchical levels to weight perturbations. In doing so, we show that the ordering of the reticular edges is more robust to noise in weight estimation than is the ordering of the tree edges. We discuss applications of this generalized Horton-Strahler ordering to the study of leaf venation and other biological networks. PMID:22701559

Mileyko, Yuriy; Edelsbrunner, Herbert; Price, Charles A.; Weitz, Joshua S.

2012-01-01

268

7 CFR 1221.18 - Order.  

Code of Federal Regulations, 2010 CFR

...MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SORGHUM PROMOTION, RESEARCH, AND INFORMATION ORDER Sorghum Promotion, Research, and Information Order Definitions § 1221.18 Order....

2010-01-01

269

7 CFR 1221.18 - Order.  

Code of Federal Regulations, 2012 CFR

...MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SORGHUM PROMOTION, RESEARCH, AND INFORMATION ORDER Sorghum Promotion, Research, and Information Order Definitions § 1221.18 Order....

2012-01-01

270

7 CFR 1221.18 - Order.  

Code of Federal Regulations, 2013 CFR

...MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SORGHUM PROMOTION, RESEARCH, AND INFORMATION ORDER Sorghum Promotion, Research, and Information Order Definitions § 1221.18 Order....

2013-01-01

271

7 CFR 1221.18 - Order.  

...MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SORGHUM PROMOTION, RESEARCH, AND INFORMATION ORDER Sorghum Promotion, Research, and Information Order Definitions § 1221.18 Order....

2014-01-01

272

7 CFR 1218.12 - Order.  

Code of Federal Regulations, 2010 CFR

...MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE BLUEBERRY PROMOTION, RESEARCH, AND INFORMATION ORDER Blueberry Promotion, Research, and Information Order Definitions § 1218.12 Order....

2010-01-01

273

7 CFR 1214.12 - Order.  

...AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE CHRISTMAS TREE PROMOTION, RESEARCH, AND INFORMATION ORDER Christmas Tree Promotion, Research, and Information Order Definitions § 1214.12 Order....

2014-01-01

274

7 CFR 1214.12 - Order.  

Code of Federal Regulations, 2013 CFR

...AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE CHRISTMAS TREE PROMOTION, RESEARCH, AND INFORMATION ORDER Christmas Tree Promotion, Research, and Information Order Definitions § 1214.12 Order....

2013-01-01

275

7 CFR 1214.12 - Order.  

Code of Federal Regulations, 2012 CFR

...AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE CHRISTMAS TREE PROMOTION, RESEARCH, AND INFORMATION ORDER Christmas Tree Promotion, Research, and Information Order Definitions § 1214.12 Order....

2012-01-01

276

Adaptive order nodal transport method  

SciTech Connect

High order nodal transport methods have demonstrated high accuracy and computational efficiency in solving transport problems for systems composed of large homogeneous regions. In addition to these properties, the Arbitrarily High Order Transport Method of the Nodal type (AHOT-N), possesses simple final equations and allows modifying the order of the spatial approximation without modifying the programming of the method. However, AHOT-N requires solving the system with the same order in all nodes and discrete directions. This feature could force the use of more equations and unknowns than needed to obtain a given accuracy with a consequent loss of computational efficiency. In a previous work a slight modification to AHOT-N was presented that allows solving a problem with a different order per node per direction. This was applied in an automatic adaptive order scheme aimed at improving the computational efficiency of AHOT-N and simplifying the error estimation of the obtained solutions. If the problem to be solved does not require a uniform order distribution (UOD), the variable order scheme could reduce significantly the number of equations and unknowns evaluated. In addition, the automatic increasing of the order depending on error estimates avoids the pre-selection of the order distribution per node per direction necessary to obtain accurate solutions, practically an impossible task that requires extensive knowledge about the shape of the solution. Since the automatic increasing of the method order depending on the estimated errors concerns data quality rather than quantity, and the optimization of user time rather than CPU time, in this work the authors focus on the behavior of the solutions obtained with the adaptive method.

Zamonsky, O.M. [Bariloche Atomic Center (Argentina); Azmy, Y.Y. [Oak Ridge National Lab., TN (United States)

1998-05-01

277

Problem Order Implications for Learning  

ERIC Educational Resources Information Center

The order of problems presented to students is an important variable that affects learning effectiveness. Previous studies have shown that solving problems in a blocked order, in which all problems of one type are completed before the student is switched to the next problem type, results in less effective performance than does solving the problems…

Li, Nan; Cohen, William W.; Koedinger, Kenneth R.

2013-01-01

278

Introduction to Order of Operations  

NSDL National Science Digital Library

This video demonstration introduces order of operations for pre-algebra level learners. The presenter explains the correct order of operations (parentheses, exponents, multiplication/division, addition/subtraction) using a simple math problem as an introductory example. Flash is required to view the video. Running time for the video is 9:39.

2010-01-01

279

First order ball bearing kinematics  

NASA Technical Reports Server (NTRS)

Two first order equations are given connecting geometry and internal motions in an angular contact ball bearing. Total speed, kinematic equivalence, basic speed ratio, and modal speed ratio are defined and discussed; charts are given for the speed ratios covering all bearings and all rotational modes. Instances where specific first order assumptions might fail are discussed, and the resulting effects on bearing performance reviewed.

Kingbury, E.

1984-01-01

280

Ordered Diagnosis #SpringerVerlag  

E-print Network

, abductive reasoning can be used to perform diagnosis [21, 3]. Rules in the fault model specify causeOrdered Diagnosis c #Springer­Verlag Davy Van Nieuwenborgh # and Dirk Vermeir ## Dept. of Computer fault model, between the various knowledge sources. It turns out that the seman­ tics for ordered logic

Vermeir, Dirk

281

Tensions between Liberty and Order.  

ERIC Educational Resources Information Center

Explores the issue of balancing liberty and order within the United States. Discusses the role of the Bill of Rights, focusing on the amendments in the document and the later amendments that ensure the liberty of U.S. citizens. Explains how order and liberty are ensured and includes discussion questions. (CMK)

Chemerinsky, Erwin

2002-01-01

282

INSTITUTE OF PHYSICS PUBLISHING SUPERCONDUCTOR SCIENCE AND TECHNOLOGY Supercond. Sci. Technol. 19 (2006) 941944 doi:10.1088/0953-2048/19/9/010  

E-print Network

-optical detection system and evaluated its performance. In the setup, we prepared Bi-substituted rare earth iron at stacks.iop.org/SUST/19/941 Abstract In order to detect the dynamic motion of local magnetic fluxes with a bias current, and also succeeded in detecting the small magnetic field induced by a bias current

Tonouchi, Masayoshi

283

Multiple order common path spectrometer  

NASA Technical Reports Server (NTRS)

The present invention relates to a dispersive spectrometer. The spectrometer allows detection of multiple orders of light on a single focal plane array by splitting the orders spatially using a dichroic assembly. A conventional dispersion mechanism such as a defraction grating disperses the light spectrally. As a result, multiple wavelength orders can be imaged on a single focal plane array of limited spectral extent, doubling (or more) the number of spectral channels as compared to a conventional spectrometer. In addition, this is achieved in a common path device.

Newbury, Amy B. (Inventor)

2010-01-01

284

Exploring Krypto (Order of Operations)  

NSDL National Science Digital Library

"The rules of Krypto — combine five numbers using the standard arithmetic operations to create a target number. The game helps to develop number sense, computational skills, and an understanding of the order of operations" from NCTM's Illuminations.

Illuminations National Council of Teachers of Mathematics

2009-07-21

285

Author Order and Research Quality  

E-print Network

We observe a great deal of heterogeneity in the manner in which author orderings are assigned both across and within academic markets. To better understand this phenomenon, we develop and analyze a stochastic model of ...

Kissan, Joseph; Laband, David N.; Patil, Vivek

2005-01-01

286

Dynamics of quadrupolar bodies in a Schwarzschild spacetime  

NASA Astrophysics Data System (ADS)

The dynamics of extended bodies endowed with multipolar structure up to the mass quadrupole moment is investigated in the Schwarzschild background according to Dixon’s model, extending previous works. The whole set of evolution equations is numerically integrated under the simplifying assumptions of constant frame components of the quadrupole tensor and that the motion of the center of mass be confined on the equatorial plane, the spin vector being orthogonal to it. The equations of motion are also solved analytically in the limit of small values of the characteristic length scales associated with the spin and quadrupole with respect to the background curvature characteristic length. The results are qualitatively and quantitatively different from previous analyses involving only spin structures. In particular, the presence of the quadrupole turns out to be responsible for the onset of a nonzero spin angular momentum, even if initially absent.

Bini, Donato; Geralico, Andrea

2013-01-01

287

Dynamics of quadrupolar bodies in a Schwarzschild spacetime  

E-print Network

The dynamics of extended bodies endowed with multipolar structure up to the mass quadrupole moment is investigated in the Schwarzschild background according to the Dixon's model, extending previous works. The whole set of evolution equations is numerically integrated under the simplifying assumptions of constant frame components of the quadrupole tensor and that the motion of the center of mass be confined on the equatorial plane, the spin vector being orthogonal to it. The equations of motion are also solved analytically in the limit of small values of the characteristic length scales associated with the spin and quadrupole with respect to the background curvature characteristic length. The results are qualitatively and quantitatively different from previous analyses involving only spin structures. In particular, the presence of the quadrupole turns out to be responsible for the onset of a non-zero spin angular momentum, even if initially absent.

Donato Bini; Andrea Geralico

2014-08-22

288

Quadrupolar ion excitation for radiofrequency-only mass filter operation.  

PubMed

Trajectory calculations are used to model a mass filter based on the radiofrequency (rf)-only operation of a linear quadrupole with resonant quadrupole excitation of ions (resonant excitation applied with the same spatial electric field as the main quadrupole rf field). Ions are not trapped, but pass continuously through the quadrupole. Excited ions gain axial kinetic energy in the fringe field at the quadrupole exit, overcome a stopping potential and are transmitted to an external detector. No quadrupole direct current is required, unlike conventional operation at the tip of the first stability diagram. Quadrupole excitation can be applied with amplitude or frequency modulation of the main rf voltage, or with an auxiliary excitation voltage. All three methods give the same mass resolution. The mass resolution, R, is given by R ? 0.5q(d?/dq)n where q is a Mathieu parameter, ?(q), determines the frequency of ion oscillation and n is the number of cycles of the rf field experienced by an ion, determined by the flight time through the quadrupole. A disadvantage of this mode of operation is that the flight times of the ions and the excitation amplitudes or modulation depths need to be synchronized. PMID:24892291

Douglas, Don J; Polyakov, A; Konenkov, Nikolai V

2014-01-01

289

Supersymmetric fifth order evolution equations  

SciTech Connect

This paper considers supersymmetric fifth order evolution equations. Within the framework of symmetry approach, we give a list containing six equations, which are (potentially) integrable systems. Among these equations, the most interesting ones include a supersymmetric Sawada-Kotera equation and a novel supersymmetric fifth order KdV equation. For the latter, we supply some properties such as a Hamiltonian structures and a possible recursion operator.

Tian, K. [LSEC, ICMSEC, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China) and Graduate School of Chinese Academy of Sciences, Beijing (China); Liu, Q. P. [Department of Mathematics, China University of Mining and Technology, Beijing 100083 (China)

2010-03-08

290

On charge and orbital ordering  

NASA Astrophysics Data System (ADS)

In recent times there has been a resurgence of interest in the properties of transition metal oxides because of the wide range of physical properties that they exhibit. Recent developments in experimental techniques offer a direct probe to the novel types of ordering realised in these systems. Using first principle band structure calculations, we have critically examined^1 the results of resonant x-ray scattering experiments which are believed to directly probe charge and orbital ordering. Considering the specific case of La_0.5Sr_1.5MnO_4, we show that this technique actually probes most directly and sensitively small structural distortions in the system. Such distortions, often difficult to detect with more conventional techniques, invariably accompany and usually cause the orbital and charge orderings. In this sense, this technique is only an indirect probe of such types of ordering. Our results also provide a microscopic explanation of the novel types of charge and orbital ordering realized in this system and other doped manganites. 1. Priya Mahadevan, K. Terakura and D.D. Sarma, Phys. Rev. Lett. 87, 066404 (2001).

Mahadevan, Priya; Terakura, K.; Sarma, Dd

2002-03-01

291

Order in a multidimensional system  

PubMed Central

We show that any convex K-dimensional system has a level of order R that is proportional to its level of Fisher information I. The proportionality constant is 1/8 the square of the longest chord connecting two surface points of the system. This result follows solely from the requirement that R decrease under small perturbations caused by a coarse graining of the system. The form for R is generally unitless, allowing the order for different phenomena, or different representations (e.g., using time vs frequency) of a given phenomenom, to be compared objectively. Order R is also invariant to uniform magnification of the system. The monotonic contraction properties of R and I define an arrow of time and imply that they are entropies, in addition to their usual status as informations. This also removes the need for data, and therefore an observer, in derivations of nonparticipatory phenomena that utilize I. Simple graphical examples of the new order measure show that it measures as well the level of “complexity” in the system. Finally, an application to cell growth during enforced distortion shows that a single hydrocarbon chain can be distorted into a membrane having equal order or complexity. Such membranes are prime constituents of living cells. PMID:21867134

Roy Frieden, B.; Gatenby, Robert A.

2014-01-01

292

Tree reconstruction from partial orders  

SciTech Connect

The problem of constructing trees given a matrix of interleaf distances is motivated by applications in computational evolutionary biology and linguistics. The general problem is to find an edge-weighted tree which most closely approximates the distance matrix. Although the construction problem is easy when the tree exactly fits the distance matrix, optimization problems under all popular criteria are either known or conjectured to be NP-complete. In this paper we consider the related problem where we are given a partial order on the pairwise distances, and wish to construct (if possible) an edge-weighted tree realizing the partial order. In particular we are interested in partial orders which arise from experiments on triples of species, which determine either a linear ordering of the three pairwise distances (called Total Order Model or TOM experiments) or only the pair(s) of minimum distance apart (called Partial Order Model or POM experiments). The POM and TOM experimental model is inspired by the model proposed by Kannan, Lawler, and Warnow for constructing trees from experiments which determine the rooted topology for any triple of species. We examine issues of construction of trees and consistency of TOM and POM experiments, where the trees may either be weighted or unweighted. Using these experiments to construct unweighted trees without nodes of degree two is motivated by a similar problem studied by Winkler, called the Discrete Metric Realization problem, which he showed to be strongly NP-hard. We have the following results: Determining consistency of a set of TOM or POM experiments is NP-Complete whether the tree is weighted or constrained to be unweighted and without degree two nodes. We can construct unweighted trees without degree two nodes from TOM experiments in optimal O(n[sup 3]) time and from POM experiments in O(n[sup 4]) time.

Kannan, S.K. (Arizona Univ., Tucson, AZ (United States)); Warnow, T.J. (Sandia National Labs., Albuquerque, NM (United States))

1993-01-01

293

Tree reconstruction from partial orders  

SciTech Connect

The problem of constructing trees given a matrix of interleaf distances is motivated by applications in computational evolutionary biology and linguistics. The general problem is to find an edge-weighted tree which most closely approximates the distance matrix. Although the construction problem is easy when the tree exactly fits the distance matrix, optimization problems under all popular criteria are either known or conjectured to be NP-complete. In this paper we consider the related problem where we are given a partial order on the pairwise distances, and wish to construct (if possible) an edge-weighted tree realizing the partial order. In particular we are interested in partial orders which arise from experiments on triples of species, which determine either a linear ordering of the three pairwise distances (called Total Order Model or TOM experiments) or only the pair(s) of minimum distance apart (called Partial Order Model or POM experiments). The POM and TOM experimental model is inspired by the model proposed by Kannan, Lawler, and Warnow for constructing trees from experiments which determine the rooted topology for any triple of species. We examine issues of construction of trees and consistency of TOM and POM experiments, where the trees may either be weighted or unweighted. Using these experiments to construct unweighted trees without nodes of degree two is motivated by a similar problem studied by Winkler, called the Discrete Metric Realization problem, which he showed to be strongly NP-hard. We have the following results: Determining consistency of a set of TOM or POM experiments is NP-Complete whether the tree is weighted or constrained to be unweighted and without degree two nodes. We can construct unweighted trees without degree two nodes from TOM experiments in optimal O(n{sup 3}) time and from POM experiments in O(n{sup 4}) time.

Kannan, S.K. [Arizona Univ., Tucson, AZ (United States); Warnow, T.J. [Sandia National Labs., Albuquerque, NM (United States)

1993-03-01

294

Executive Order 1095 Attachment C  

E-print Network

Executive Order 1095 Attachment C Page 1 of 17 RIGHTS AND OPTIONS FOR VICTIMS OF SEXUAL VIOLENCE and sustaining an educational and working environment free of sexual violence, dating violence, domestic violence/or the campus Title IX Coordinator. You have the right to decide who and when to tell about sexual violence

Su, Xiao

295

PEMDAS: Algebraic Order of Operations  

NSDL National Science Digital Library

Watch this music video to help you learn about PEMDAS (Please Excuse My Dear Aunt Sally). Does this sound familiar? If not, this is an excellent device to memorize the algebraic order of operations. This video is produced by Mr. Davis Productions and plays music by Odyssey Sound Lab.

2009-03-15

296

Optimal scaling for ordered categories  

Microsoft Academic Search

This paper deals with the determination of optimal weights for points on scoring scales for subjective comparative experiments. A scoring scale with a specific number of points is considered, and it is assumed that verbal or other indications imply an order to the scale points. The optimal spacing for the scale points is obtained in the sense that treatment or

R. A. Bradley; S. K. Katti; Irma J. Coons

1962-01-01

297

Executive Order 1095 Attachment B  

E-print Network

, alcohol or other drugs to engage in sexual activity. · Take responsibility for your actions. · AvoidExecutive Order 1095 Attachment B Page 1 of 10 Myths and Facts about Sexual Violence What You Can Do To Help Stop Sexual Violence · Sexual contact requires mutual consent. An incapacitated person

Su, Xiao

298

NCI Mouse Repository - Ordering Information  

Cancer.gov

Mouse models are provided free of charge through the NCI Mouse Repository, however, the customer is responsible for shipping charges if the shipment must go by air or special truck. There is no charge for normal truck delivery. Up to three (3) breeder pairs are routinely supplied on an order. On occasion, larger numbers of breeder pairs may be available - please inquire.

299

Moral Order and the Humanities.  

ERIC Educational Resources Information Center

Argues that a society without reverence for myths and history inevitably falls prone to chaos and evil, pointing to abortion, Andy Warhol's celebrity, and Woodstock as evidence of this disintegration of society. Proposes that humanities education expose students to human experience based on some awesome and fixed moral order. (AYC)

Howard, Thomas

1980-01-01

300

Birth order and intellectual development  

Microsoft Academic Search

Describes a confluence model that explains the effects of birth order and family size on intelligence. Intellectual development within the family context is conceived of as depending on the cumulative effects of the intellectual environment, which consists primarily of the siblings' and parents' intelligence. Mutual influences, through time, on the intellectual development of the siblings are described by the growth

R. B. Zajonc; Gregory B. Markus

1975-01-01

301

Generalized high order compact methods.  

SciTech Connect

The fundamental ideas of the high order compact method are combined with the generalized finite difference method. The result is a finite difference method that works on unstructured, nonuniform grids, and is more accurate than one would classically expect from the number of grid points employed.

Spotz, William F.; Kominiarczuk, Jakub (University of California at Berkeley)

2010-09-01

302

Stochastic ordering of extreme value distributions  

Microsoft Academic Search

We investigate the second-order stochastic ordering of the extreme value distributions within each of three families: the Gumbel distribution, the Frechet distribution, and the Weibull distribution. We give conditions for second-order stochastic dominance, conditional second-order stochastic dominance, and order statistics second-order stochastic dominance within the three families

Ganghuai Wang; James H. Lambert; Yacov Y. Haimes

1999-01-01

303

Recent advances in ordered intermetallics  

SciTech Connect

Ordered intermetallic alloys based on aluminides and silicides offer many advantages for structural use at high temperatures in hostile environments. Attractive properties include excellent oxidation and corrosion resistance, light weight, and superior strength at high temperatures. The major concern for structural use of intermetallics was their low ductility and poor fracture resistance at ambient temperatures. For the past 10 years, considerable effort was devoted to R&D of ordered intermetallic alloys, and progress has been made on understanding intrinsic and extrinsic factors controlling brittle fracture in intermetallic alloys based on aluminides and silicides. Parallel effort on alloy design has led to the development of a number of ductile and strong intermetallic alloys based on Ni{sub 3}Al, NiAl, Fe{sub 3}Al, FeAl, Ti{sub 3}Al, and TiAl systems for structural applications.

Liu, C.T.

1994-12-31

304

Ordering Juice Drinks (grade 4)  

NSDL National Science Digital Library

This is a sample PARCC assessment task based on CCSS grade 4 operations and algebraic thinking standards as well as the number and operations in base ten standards. In this interactive single task students must solve a multi-step problem by completing an order receipt for orange juice. Included are the alignments to the CCSS, a scoring rubric and background on the task itself.

2013-01-01

305

Torn Shirts Inc: Telephone Orders  

NSDL National Science Digital Library

A challenging but well-guided activity, Torn Shirts has students analyze data to reach a decision on a business question. They first determine the probability that a customer calling to order a shirt gets a busy signal, then estimate the amount of money the company might lose when customers get a busy signal. Work with graphs and averages, especially the median, helps students reach a conclusion.

Research, High S.; Chien, Ellen; Lawson, Marlene; Snyder, Helen

1996-01-01

306

Highly Ordered Noncrystalline Metallic Phase  

NASA Astrophysics Data System (ADS)

We report the characterization of a unique metallic glass that, during rapid cooling of an Al-Fe-Si melt, forms by nucleation, followed by growth normal to a moving interface between the solid and melt with partitioning of the chemical elements. We determine experimentally that this is not a polycrystalline composite with nanometer-sized grains, and conclude that this may be a new kind of structure: an atomically ordered, isotropic, noncrystalline solid, possessing no long-range translational symmetry.

Long, Gabrielle G.; Chapman, Karena W.; Chupas, Peter J.; Bendersky, Leonid A.; Levine, Lyle E.; Mompiou, Frédéric; Stalick, Judith K.; Cahn, John W.

2013-07-01

307

The social order of markets  

Microsoft Academic Search

In this article I develop a proposal for the theoretical vantage point of the sociology of markets, focusing on the problem\\u000a of the social order of markets. The initial premise is that markets are highly demanding arenas of social interaction, which\\u000a can only operate if three inevitable coordination problems are resolved. I define these coordination problems as the value problem,

Jens Beckert

2009-01-01

308

Order stars and stability theorems  

Microsoft Academic Search

This paper clears up to the following three conjectures:1.The conjecture of Ehle [1] on theA-acceptability of Padé approximations toez, which is true;2.The conjecture of Nørsett [5] on the zeros of the “E-polynomial”, which is false;3.The conjecture of Daniel and Moore [2] on the highest attainable order of certainA-stable multistep methods, which is true, generalizing the well-known Theorem of Dahlquist.

G. Wanner; E. Hairer; S. P. Nørsett

1978-01-01

309

Hidden order in the cuprates  

Microsoft Academic Search

We propose that the enigmatic pseudogap phase of cuprate superconductors is characterized by a hidden broken symmetry of d_x^2-y^2-type. The transition to this state is rounded by disorder, but in the limit that the disorder is made sufficiently small, the pseudogap crossover should reveal itself to be such a transition. The ordered state breaks time-reversal, translational, and rotational symmetries, but

Chetan Nayak; R. B. Laughlin; Dirk Morr

2001-01-01

310

Application of one-dimensional nutation nuclear magnetic resonance to 51V in ferroelastic BiVO4.  

PubMed

The central line intensity of a spin I = 7/2, excited by a radio frequency (rf) pulse, is calculated by taking into account the first-order quadrupolar interaction during excitation. Thus, the result is valid for any ratio of quadrupolar coupling to pulse amplitude. The quadrupolar coupling of the nuclei vanadium 51V in a single crystal of ferroelastic BiVO4 is determined using this one-dimensional (1D) mutation method. PMID:7834322

Man, P P; Choh, S H; Fraissard, J

1994-08-01

311

Biocatalytic induction of supramolecular order  

NASA Astrophysics Data System (ADS)

Supramolecular gels, which demonstrate tunable functionalities, have attracted much interest in a range of areas, including healthcare, environmental protection and energy-related technologies. Preparing these materials in a reliable manner is challenging, with an increased level of kinetic defects observed at higher self-assembly rates. Here, by combining biocatalysis and molecular self-assembly, we have shown the ability to more quickly access higher-ordered structures. By simply increasing enzyme concentration, supramolecular order expressed at molecular, nano- and micro-levels is dramatically enhanced, and, importantly, the gelator concentrations remain identical. Amphiphile molecules were prepared by attaching an aromatic moiety to a dipeptide backbone capped with a methyl ester. Their self-assembly was induced by an enzyme that hydrolysed the ester. Different enzyme concentrations altered the catalytic activity and size of the enzyme clusters, affecting their mobility. This allowed structurally diverse materials that represent local minima in the free energy landscape to be accessed based on a single gelator structure.

Hirst, Andrew R.; Roy, Sangita; Arora, Meenakshi; Das, Apurba K.; Hodson, Nigel; Murray, Paul; Marshall, Stephen; Javid, Nadeem; Sefcik, Jan; Boekhoven, Job; van Esch, Jan H.; Santabarbara, Stefano; Hunt, Neil T.; Ulijn, Rein V.

2010-12-01

312

Ordering Phenomena in Undercooled Alloys  

SciTech Connect

Much of the work performed under this grant was devoted to using modern ideas in kinetics to understand atom movements in metallic alloys far from thermodynamic equilibrium. Kinetics arguments were based explicitly on the vacancy mechanism for atom movements. The emphasis was on how individual atom movements are influenced by the local chemical environment of the moving atom, and how atom movements cause changes in the local chemical environments. The author formulated a kinetic master equation method to treat atom movements on a crystal lattice with a vacancy mechanism. Some of these analyses [3,10,16] are as detailed as any treatment of the statistical kinetics of atom movements in crystalline alloys. Three results came from this work. Chronologically they were (1) A recognition that tracking time dependencies is not necessarily the best way to study kinetic phenomena. If multiple order parameters can be measured in a material, the ''kinetic path'' through the space spanned by these order parameters maybe just as informative about the chemical factors that affect atom movements [2,3,5-7,9-11,14-16,18,19,21,23,24,26,36,37]. (2) Kinetic paths need not follow the steepest gradient of the free energy function (this should be well-known), and for alloys far from equilibrium the free energy function can be almost useless in describing kinetic behavior. This is why the third result surprised me. (3) In cluster approximations with multiple order parameters, saddle points are common features of free energy functions. Interestingly, kinetic processes stall or change time scale when the kinetic path approaches a state at a saddle point in the free energy function, even though these states exist far from thermodynamic equilibrium. The author calls such a state a ''pseudostable'' (falsely stable) state [6,21,26]. I have also studied these phenomena by more ''exact'' Monte Carlo simulations. The kinetic paths showed features similar to those found in analytical theories. The author found that a microstructure with interfaces arranged in space as a periodic minimal surface is a probably an alloy at a saddle point in its free energy function [21,26,37].

Fultz, Brent

1997-07-17

313

Dependency Ordering of Atomic Observables  

NASA Astrophysics Data System (ADS)

The notion of atomic observable was introduced by S.Gudder for effect test spaces in 1997. In this paper an observable is a ?-homomorphism from the Borel algebra on a line to some logic. Roughly, an observable on a logic is atomic, if it is completely determined by its restriction to one-element subsets of its point spectrum. In particular, every discrete observable is atomic. We study some elementary properties of such observables, and discuss a possible notion of functional dependency between them. Algebraically, a dependency is a certain preorder relation on the set of all atomic observables, which induces an order relation on the set of all maximal orthogonal subsets of the logic. Several properties, as well as characteristics in terms of the underlying logic, of these relations are stated.

C?rulis, J?nis

2015-01-01

314

CONFIDENCE INTERVALS UNDER ORDER RESTRICTIONS  

PubMed Central

In this paper, we consider the problem of constructing confidence intervals (CIs) for G independent normal population means subject to linear ordering constraints. For this problem, CIs based on asymptotic distributions, likelihood ratio tests and bootstraps do not have good properties particularly when some of the population means are close to each other. We propose a new method based on defining intermediate random variables that are related to the original observations and using the CIs of the means of these intermediate random variables to restrict the original CIs from the separate groups. The coverage rates of the intervals are shown to exceed, but be close to, the nominal level for two groups, when the ratio of the variances is assumed known. Simulation studies show that the proposed CIs have coverage rates close to nominal levels with reduced average widths. Data on half-lives of an antibiotic are analyzed to illustrate the method. PMID:24505210

Park, Yongseok; Kalbfleisch, John D.; Taylor, Jeremy M.G.

2013-01-01

315

Order in the Piazzi case.  

PubMed

University Health Services, Inc. petitioned the Superior Court of Richmond County, Georgia, for an order to maintain life support systems for Donna Piazzi, a brain dead patient, to preserve the life of her quickened, nonviable fetus until the point of delivery with a reasonable chance of survival. Robert Piazzi, the husband, requested termination of support. The guardian ad litem of the fetus and David Haddon, the putative father, requested maintenance of support. The Division of Family and Children Services argued that the Court lacked jurisdiction. The Court concluded that, based on case law and on Georgia statutes, only the mother has the right to terminate a quickened, nonviable fetus and that public policy requires the maintenance of life support systems for a brain dead mother as long as there exists a reasonable possibility that the fetus may develop and survive. PMID:11644465

1987-03-01

316

7 CFR 1230.610 - Order.  

Code of Federal Regulations, 2013 CFR

...ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PORK PROMOTION, RESEARCH, AND CONSUMER INFORMATION Procedures...Definitions § 1230.610 Order. The term Order means the Pork Promotion, Research, and Consumer Information...

2013-01-01

317

40 CFR 89.503 - Test orders.  

Code of Federal Regulations, 2010 CFR

...NONROAD COMPRESSION-IGNITION ENGINES Selective Enforcement Auditing § 89.503 Test orders. (a) A test order addressed...may not issue to a manufacturer more Selective Enforcement Auditing (SEA) test orders than an annual limit determined to be...

2010-07-01

318

6 CFR 27.300 - Orders.  

Code of Federal Regulations, 2010 CFR

...Section 27.300 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY CHEMICAL FACILITY ANTI-TERRORISM STANDARDS Orders and Adjudications § 27.300 Orders. (a) Orders Generally. When the Assistant...

2010-01-01

319

7 CFR 1212.15 - Order.  

Code of Federal Regulations, 2010 CFR

...COMMODITIES), DEPARTMENT OF AGRICULTURE HONEY PACKERS AND IMPORTERS RESEARCH, PROMOTION...EDUCATION AND INDUSTRY INFORMATION ORDER Honey Packers and Importers Research, Promotion...1212.15 Order. “Order” means the Honey Packers and Importers Research,...

2010-01-01

320

Deriving Laws from Ordering Relations  

NASA Technical Reports Server (NTRS)

It took much effort in the early days of non-Euclidean geometry to break away from the mindset that all spaces are flat and that two distinct parallel lines do not cross. Up to that point, all that was known was Euclidean geometry, and it was difficult to imagine anything else. We have suffered a similar handicap brought on by the enormous relevance of Boolean algebra to the problems of our age-logic and set theory. Previously, I demonstrated that the algebra of questions is not Boolean, but rather is described by the free distributive algebra. To get to this stage took much effort, as many obstacles-most self-placed-had to be overcome. As Boolean algebras were all I had ever known, it was almost impossible for me to imagine working with an algebra where elements do not have complements. With this realization, it became very clear that the sum and product rules of probability theory at the most basic level had absolutely nothing to do with the Boolean algebra of logical statements. Instead, a measure of degree of inclusion can be invented for many different partially ordered sets, and the sum and product rules fall out of the associativity and distributivity of the algebra. To reinforce this very important idea, this paper will go over how these constructions are made, while focusing on the underlying assumptions. I will derive the sum and product rules for a distributive lattice in general and demonstrate how this leads to probability theory on the Boolean lattice and is related to the calculus of quantum mechanical amplitudes on the partially ordered set of experimental setups. I will also discuss the rules that can be derived from modular lattices and their relevance to the cross-ratio of projective geometry.

Knuth, Kevin H.

2003-01-01

321

The type II superstring to order ? 4  

NASA Astrophysics Data System (ADS)

The Green-Schwarz superstring action in a general type IIA or IIB supergravity background is derived up to fourth order in the Grassmann-odd coordinates ?. This is done by solving the superspace Bianchi identities order by order in ?, to quadratic order for all superfields and to quartic order for the supervielbeins. For a large class of backgrounds it is possible to fix the kappa symmetry in such a way that the action actually terminates at the quartic order in ?.

Wulff, Linus

2013-07-01

322

Multilevel hierarchically ordered artificial biomineral.  

PubMed

Living organisms are known for creating complex organic-inorganic hybrid materials such as bone, teeth, and shells, which possess outstanding functions as compared to their simple mineral forms. This has inspired many attempts to mimic such structures, but has yielded few practical advances. In this study, a multilevel hierarchically ordered artificial biomineral (a composite of hydroxyapatite and gelatine) with favorable nanomechanical properties is reported. A typical optimized HAp/gelatin hybrid material in the perpendicular direction of the HAp c-axis has a modulus of 25.91 + 1.78 GPa and hardness of 0.90 + 0.10 GPa, which well matches that of human cortical bone (modulus 24.3 + 1.4 GPa, hardness 0.69 + 0.05 GPa). The bottom-up crystal constructions (from nano- to micro- to macroscale) of this material are achieved through a hard template approach by the phase transformation from DCP to HAp. The structural biomimetic material shows another way to mimic the complex hierarchical designs of sclerous tissues which have potential value for application in hard tissue engineering. PMID:23847156

Liu, Xiaoguo; Lin, Kaili; Wu, Chengtie; Wang, Yueyue; Zou, Zhaoyong; Chang, Jiang

2014-01-15

323

Advanced ordered intermetallic alloy deployment  

SciTech Connect

The need for high-strength, high-temperature, and light-weight materials for structural applications has generated a great deal of interest in ordered intermetallic alloys, particularly in {gamma}-based titanium aluminides {gamma}-based TiAl alloys offer an attractive mix of low density ({approximately}4g/cm{sup 3}), good creep resistance, and high-temperature strength and oxidation resistance. For rotating or high-speed components. TiAl also has a high damping coefficient which minimizes vibrations and noise. These alloys generally contain two phases. {alpha}{sub 2} (DO{sub 19} structure) and {gamma} (L 1{sub 0}), at temperatures below 1120{degrees}C, the euticoid temperature. The mechanical properties of TiAl-based alloys are sensitive to both alloy compositions and microstructure. Depending on heat-treatment and thermomechanical processing, microstructures with near equiaxed {gamma}, a duplex structure (a mix of the {gamma} and {alpha}{sub 2} phases) can be developed in TiAl alloys containing 45 to 50 at. % Al. The major concern for structural use of TiAl alloys is their low ductility and poor fracture resistance at ambient temperatures. The purpose of this project is to improve the fracture toughness of TiAl-based alloys by controlling alloy composition, microstructure and thermomechanical treatment. This work is expected to lead to the development of TiAl alloys with significantly improved fracture toughness and tensile ductility for structural use.

Liu, C.T.; Maziasz, P.J.; Easton, D.S. [Oak Ridge National Lab., TN (United States)

1997-04-01

324

Liquid crystalline order in mucus  

NASA Technical Reports Server (NTRS)

Mucus plays an exceptionally wide range of important biological roles. It operates as a protective, exchange, and transport medium in the digestive, respiratory, and reproductive systems of humans and other vertebrates. Mucus is a polymer hydrogel. It is secreted as discrete packages (secretory granules) by specialized secretory cells. Mucus hydrogel is stored in a condensed state inside the secretory granules. Depending upon the architecture of their constituent macromolecules and on the composition of the solvent, polymer gels can form liquid crystalline microstructures, with orientational order being exhibited over optically resolvable distances. Individual mucin molecules consist of alternating rigid segments (heavily glycosylated; hydrophilic) and flexible segments (nonglycosylated; hydrophobic). Polymer molecules consisting of rigid units linked by flexible spacers are frequently associated with liquid crystalline behavior, which again raises the possibility that mucus could form anisotropic fluid phases. Suggestions that mucins may be self-associating in dilute solution have previously been challenged on the basis of sedimentation-equilibrium studies performed on mucus in which potential sites of association were competitively blocked with inhibitors. However, the formation of stable liquid crystalline phases does not depend on the existence of inter- or intramolecular associations; these phases can form on the basis of steric considerations alone.

Viney, C.; Huber, A. E.; Verdugo, P.

1993-01-01

325

Repeated Red-Black ordering  

NASA Astrophysics Data System (ADS)

Hereafter, we describe and analyze, from both a theoretical and a numerical point of view, an iterative method for efficiently solving symmetric elliptic problems with possibly discontinuous coefficients. In the following, we use the Preconditioned Conjugate Gradient method to solve the symmetric positive definite linear systems which arise from the finite element discretization of the problems. We focus our interest on sparse and efficient preconditioners. In order to define the preconditioners, we perform two steps: first we reorder the unknowns and then we carry out a (modified) incomplete factorization of the original matrix. We study numerically and theoretically two preconditioners, the second preconditioner corresponding to the one investigated by Brand and Heinemann [2]. We prove convergence results about the Poisson equation with either Dirichlet or periodic boundary conditions. For a meshsizeh, Brand proved that the condition number of the preconditioned system is bounded byO(h-1/2) for Dirichlet boundary conditions. By slightly modifying the preconditioning process, we prove that the condition number is bounded byO(h-1/3).

Ciarlet, P.

1994-09-01

326

Fourth order spatial derivative gravity  

SciTech Connect

In this work, we study a modified theory of gravity that contains up to fourth order spatial derivatives as a model for the Horava-Lifshitz gravity. The propagator is evaluated and, as a result, one extra pole is obtained, corresponding to a spin-2 nonrelativistic massless particle, an extra term which jeopardizes renormalizability, besides the unexpected general relativity unmodified propagator. Then unitarity is proved at the tree level, where the general relativity pole has been shown to have no dynamics, remaining only the 2 degrees of freedom of the new pole. Next, the nonrelativistic effective potential is determined from a scattering process of two identical massive gravitationally interacting bosons. In this limit, Newton's potential is obtained, together with a Darwin-like term that comes from the extra nonpole term in the propagator. Regarding renormalizability, this extra term may be harmful by power counting, but it can be eliminated by adjusting the free parameters of the model. This adjustment is in accord with the detailed balance condition suggested in the literature and shows that the way in which extra spatial derivative terms are added is of fundamental importance.

Bemfica, F. S.; Gomes, M. [Instituto de Fisica, Universidade de Sao Paulo Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil)

2011-10-15

327

Diagnosing deconfinement and topological order  

NASA Astrophysics Data System (ADS)

Topological or deconfined phases are characterized by emergent, weakly fluctuating, gauge fields. In condensed matter settings, they inevitably come coupled to excitations that carry the corresponding gauge charges which invalidate the standard diagnostic of deconfinement—the Wilson loop. Inspired by a mapping between symmetric sponges and the deconfined phase of the Z2 gauge theory, we construct a diagnostic for deconfinement that has the interpretation of a line tension. One operator version of this diagnostic turns out to be the Fredenhagen-Marcu order parameter known to lattice gauge theorists and we show that a different version is best suited to condensed matter systems. We discuss generalizations of the diagnostic, use it to establish the existence of finite temperature topological phases in d>=3 dimensions and show that multiplets of the diagnostic are useful in settings with multiple phases, such as U(1) gauge theories with charge q matter. (Additionally, we present an exact reduction of the partition function of the toric code in general dimensions to a well-studied problem.)

Gregor, K.; Huse, David A.; Moessner, R.; Sondhi, S. L.

2011-02-01

328

Interior order expands minerals management  

NASA Astrophysics Data System (ADS)

In a surprise move on May 10, Secretary of the Interior James G. Watt ordered the consolidation of all leasing and resource management functions for the outer continental shelf (OCS) into the Minerals Management Service (MMS). Among those programs shifted to MMS are ‘all functions in direct support of the OCS program’ in the Geologic Division and in the Office of the Assistant Director for Resource Programs of the U.S. Geological Survey (USGS), including oil and gas resources, energy-related hazards, and marine geology investigations. It is unclear whether research associated with the OCS leasing functions will be considered ‘direct support’ and what will happen to the research if it is so considered.Also to be shuttled to MMS are the oil-spill trajectory functions of the Office of Earth Sciences Applications and all the functions of the Office of Policy Analysis relating to the OCS that had been transferred from the Department of Energy as a result of the Interior and Related Agencies Appropriations Act.

Richman, Barbara T.

329

46 CFR Sec. 7 - Job order numbering.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Job order numbering. Sec. 7 Section 7...REPAIR CONTRACT-NSA-LUMPSUMREP Sec. 7 Job order numbering. (a) The NSA-LUMPSUMREP...Contract number shall be inserted in every job order and supplemental job order...

2012-10-01

330

46 CFR Sec. 7 - Job order numbering.  

...2014-10-01 2014-10-01 false Job order numbering. Sec. 7 Section 7...REPAIR CONTRACT-NSA-LUMPSUMREP Sec. 7 Job order numbering. (a) The NSA-LUMPSUMREP...Contract number shall be inserted in every job order and supplemental job order...

2014-10-01

331

46 CFR Sec. 7 - Job order numbering.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Job order numbering. Sec. 7 Section 7...REPAIR CONTRACT-NSA-LUMPSUMREP Sec. 7 Job order numbering. (a) The NSA-LUMPSUMREP...Contract number shall be inserted in every job order and supplemental job order...

2011-10-01

332

46 CFR Sec. 7 - Job order numbering.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Job order numbering. Sec. 7 Section 7...REPAIR CONTRACT-NSA-LUMPSUMREP Sec. 7 Job order numbering. (a) The NSA-LUMPSUMREP...Contract number shall be inserted in every job order and supplemental job order...

2013-10-01

333

46 CFR Sec. 7 - Job order numbering.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Job order numbering. Sec. 7 Section 7...REPAIR CONTRACT-NSA-LUMPSUMREP Sec. 7 Job order numbering. (a) The NSA-LUMPSUMREP...Contract number shall be inserted in every job order and supplemental job order...

2010-10-01

334

GLHEPRO Ordering Instructions April 20, 2009  

E-print Network

is available for $50. The $50 can be credited when you order the full version. The catalog number is shown orders, an extra charge will be added. § Orders from outside US must be made using a credit card, bank, you would simply order one of the three versions below. The catalog numbers are shown in parentheses

335

A fractional order PID tuning algorithm for a class of fractional order plants  

Microsoft Academic Search

Fractional order dynamic model could model various real materials more adequately than integer order ones and provide a more adequate description of many actual dynamical processes. Fractional order controller is naturally suitable for these fractional order models. In this paper, a fractional order PID controller design method is proposed for a class of fractional order system models. Better performance using

Chunna Zhao; Dingyu Xue; YangQuan Chen

2005-01-01

336

48 CFR 552.216-74 - Task-Order and Delivery-Order Ombudsman.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Task-Order and Delivery-Order Ombudsman. 552.216-74...Clauses 552.216-74 Task-Order and Delivery-Order Ombudsman. As prescribed...following clause: Task-Order and Delivery-Order Ombudsman (AUG 2010)...

2012-10-01

337

48 CFR 552.216-74 - Task-Order and Delivery-Order Ombudsman.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Task-Order and Delivery-Order Ombudsman. 552.216-74...Clauses 552.216-74 Task-Order and Delivery-Order Ombudsman. As prescribed...following clause: Task-Order and Delivery-Order Ombudsman (AUG 2010)...

2011-10-01

338

48 CFR 552.216-74 - Task-Order and Delivery-Order Ombudsman.  

...2014-10-01 false Task-Order and Delivery-Order Ombudsman. 552.216-74...Clauses 552.216-74 Task-Order and Delivery-Order Ombudsman. As prescribed...following clause: Task-Order and Delivery-Order Ombudsman (AUG 2010)...

2014-10-01

339

48 CFR 552.216-74 - Task-Order and Delivery-Order Ombudsman.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Task-Order and Delivery-Order Ombudsman. 552.216-74...Clauses 552.216-74 Task-Order and Delivery-Order Ombudsman. As prescribed...following clause: Task-Order and Delivery-Order Ombudsman (AUG 2010)...

2010-10-01

340

48 CFR 552.216-74 - Task-Order and Delivery-Order Ombudsman.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Task-Order and Delivery-Order Ombudsman. 552.216-74...Clauses 552.216-74 Task-Order and Delivery-Order Ombudsman. As prescribed...following clause: Task-Order and Delivery-Order Ombudsman (AUG 2010)...

2013-10-01

341

25 CFR 117.20 - Purchase orders.  

Code of Federal Regulations, 2013 CFR

...ACTIVITIES DEPOSIT AND EXPENDITURE OF INDIVIDUAL FUNDS OF MEMBERS OF THE OSAGE TRIBE OF INDIANS WHO DO NOT HAVE CERTIFICATES OF COMPETENCY § 117.20 Purchase orders. Purchase orders may be issued by the superintendent for expenditures authorized by the...

2013-04-01

342

25 CFR 117.20 - Purchase orders.  

...ACTIVITIES DEPOSIT AND EXPENDITURE OF INDIVIDUAL FUNDS OF MEMBERS OF THE OSAGE TRIBE OF INDIANS WHO DO NOT HAVE CERTIFICATES OF COMPETENCY § 117.20 Purchase orders. Purchase orders may be issued by the superintendent for expenditures authorized by the...

2014-04-01

343

25 CFR 117.20 - Purchase orders.  

Code of Federal Regulations, 2010 CFR

...ACTIVITIES DEPOSIT AND EXPENDITURE OF INDIVIDUAL FUNDS OF MEMBERS OF THE OSAGE TRIBE OF INDIANS WHO DO NOT HAVE CERTIFICATES OF COMPETENCY § 117.20 Purchase orders. Purchase orders may be issued by the superintendent for expenditures authorized by the...

2010-04-01

344

25 CFR 117.20 - Purchase orders.  

Code of Federal Regulations, 2011 CFR

...ACTIVITIES DEPOSIT AND EXPENDITURE OF INDIVIDUAL FUNDS OF MEMBERS OF THE OSAGE TRIBE OF INDIANS WHO DO NOT HAVE CERTIFICATES OF COMPETENCY § 117.20 Purchase orders. Purchase orders may be issued by the superintendent for expenditures authorized by the...

2011-04-01

345

25 CFR 117.20 - Purchase orders.  

Code of Federal Regulations, 2012 CFR

...ACTIVITIES DEPOSIT AND EXPENDITURE OF INDIVIDUAL FUNDS OF MEMBERS OF THE OSAGE TRIBE OF INDIANS WHO DO NOT HAVE CERTIFICATES OF COMPETENCY § 117.20 Purchase orders. Purchase orders may be issued by the superintendent for expenditures authorized by the...

2012-04-01

346

14 CFR 1264.123 - Protective order.  

Code of Federal Regulations, 2011 CFR

... 2010-01-01 true Protective order. 1264.123 Section 1264.123 Aeronautics and Space NATIONAL AERONAUTICS AND...PROGRAM FRAUD CIVIL PENALTIES ACT OF 1986 § 1264.123 Protective order. (a) A party or a...

2011-01-01

347

Ordered Rate Constitutive Theories in Eulerian Description  

E-print Network

law, Carreau-Yasuda model for viscosity, power law, Sutherland law etc. for temperature dependent material coefficients are a subset of the general ordered rate constitutive theories of order n for thermofluids (iii) Maxwell model, Oldroyd-B model...

Nunez, Daniel

2012-12-31

348

The Construction of Ordering-Based Modifiers  

Microsoft Academic Search

Ordering-based modifiers can be particularly useful in fuzzy control and other fields related to fuzzy systems. This paper deals with the construction of such modifiers by means of hull operators with respect to fuzzy orderings.

Ulrich Bodenhofer

1999-01-01

349

Prioritization and control of order picking system  

E-print Network

Order Picking System (OPS) efficiency at a warehouse was studied with the goal of reducing production order lead time to 8 hours. Current material flow system and strategy were studied through interviews with personnel ...

Kanburapa, Prachyathit

2013-01-01

350

78 FR 26784 - David Freeman: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2012-N-0865] David Freeman: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the...

2013-05-08

351

76 FR 69272 - Gayle Rothenberg: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2011-N-0444] Gayle Rothenberg: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the...

2011-11-08

352

76 FR 11789 - Albert Poet: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2010-N-0478] Albert Poet: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the...

2011-03-03

353

75 FR 5332 - Brian Ullom: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2009-N-0420] Brian Ullom: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the act)...

2010-02-02

354

76 FR 12971 - Anastasios Pappas: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...Anastasios Pappas: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the...

2011-03-09

355

78 FR 14304 - Adrian Vela: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2012-N-0777] Adrian Vela: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the...

2013-03-05

356

75 FR 17927 - Kevin Xu: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2009-N-0286] Kevin Xu: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the act)...

2010-04-08

357

75 FR 49497 - John Bonnes: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2010-N-0305] John Bonnes: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (the act)...

2010-08-13

358

46 CFR 5.567 - Order.  

Code of Federal Regulations, 2010 CFR

...revocation . (b) The order is directed against all credentials or endorsements, except that in cases of negligence or professional incompetence, the order is made applicable to specific credentials or endorsements. If the...

2010-10-01

359

40 CFR 91.604 - Test orders.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Selective Enforcement Auditing Regulations § 91.604 Test orders. (a) A test order addressed to the manufacturer is required for any testing...

2010-07-01

360

Tunable fractional-order Fourier transformer  

SciTech Connect

A fractional two-dimensional Fourier transformer whose orders are tuned by means of optical quadrupoles is described. It is shown that in the optical scheme considered, the Fourier-transform order a element of [0,1] in one of the mutually orthogonal planes corresponds to the transform order (2-a) in another plane, i.e., to inversion and inverse Fourier transform of the order a. (laser modes and beams)

Malyutin, A A [A.M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2006-01-31

361

Source of second order chromaticity in RHIC  

SciTech Connect

In this note we will answer the following questions: (1) what is the source of second order chromaticities in RHIC? (2) what is the dependence of second order chromaticity on the on-momentum {beta}-beat? (3) what is the dependence of second order chromaticity on {beta}* at IP6 and IP8? To answer these questions, we use the perturbation theory to numerically calculate the contributions of each quadrupole and sextupole to the first, second, and third order chromaticities.

Luo, Y.; Gu, X.; Fischer, W.; Trbojevic, D.

2011-01-01

362

Field-Induced Magnetostructural Transitions in Antiferromagnetic Fe1+ y Te1- x S x  

NASA Astrophysics Data System (ADS)

Transport and structural properties of Fe1+ y Te1- x S x were studied in pulsed magnetic fields. Application of high magnetic fields induces first order transitions showing positive magnetoresistance effects in the antiferromagnetic phase. Polarizing microscope images taken at high magnetic fields revealed the concomitant melting of the orbital order. These results indicate the importance of crossed coupling between spin and lattice or orbital degrees of freedom in this compound.

Tokunaga, M.; Kihara, T.; Mizuguchi, Y.; Takano, Y.

2013-03-01

363

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

Microsoft Academic Search

The quadrupolarity of carbon dioxide has been studied with higher level ab initio methods. Carbon dioxide exhibits {? + ?} quadrupolarity in all directions and an explanation is provided of the origin of the sign of the diagonal elements Qii. The quadrupole moment tensor has been computed using restricted Hartree–Fock theory, second-order Møller–Plesset perturbation theory and quadratic configuration interaction theory.

R. Glaser; Z. Wu; M. Lewis

2000-01-01

364

Spontaneous ordering of nanostructures on crystal surfaces  

Microsoft Academic Search

A review is given of theoretical concepts and experimental results on spontaneous formation of periodically ordered nanometer-scale structures on crystal surfaces. Thermodynamic theory is reviewed for various classes of spontaneously ordered nanostructures, namely, for periodically faceted surfaces, for periodic surface structures of planar domains, and for ordered arrays of three-dimensional coherently strained islands. All these structures are described as equilibrium

Vitaliy A. Shchukin; Dieter Bimberg

1999-01-01

365

Discovering Injective Episodes with General Partial Orders  

Microsoft Academic Search

Frequent episode discovery is a popular framework for temporal pattern discovery in event streams. An episode is a partially ordered set of nodes with each node associated with an event type. Currently algorithms exist for episode discovery only when the associated partial order is total order (serial episode) or trivial (parallel episode). In this paper, we propose efficient algorithms for

Avinash Achar; Srivatsan Laxman; Raajay Viswanathan; P. S. Sastry

2012-01-01

366

Higher-order closures and cloud parameterizations  

E-print Network

Higher-order closures and cloud parameterizations Jean-Christophe Golaz National Research Council Sciences University of Wisconsin --- Milwaukee #12;Outline · What is higher-order closure? · Historical we prognose cloud fraction? · Sample results · Conclusions #12;What is higher-order closure

367

An Analysis of Second-Order Autoshaping  

ERIC Educational Resources Information Center

Three mechanisms can explain second-order conditioning: (1) The second-order conditioned stimulus (CS2) could activate a representation of the first-order conditioned stimulus (CS1), thereby provoking the conditioned response (CR); The CS2 could enter into an excitatory association with either (2) the representation governing the CR, or (3) with a…

Ward-Robinson, Jasper

2004-01-01

368

Spontaneous order: Michael Polanyi and Friedrich Hayek  

Microsoft Academic Search

This paper compares Hayek and Polanyi on spontaneous social order. Although Hayek is widely believed to have first both coined the name and explicated the idea of ‘spontaneous order’, it is in fact Michael Polanyi who did so. Numerous differences emerge between the two thinkers. The characterisation of spontaneous order in Hayek, for example, involves different types of freedom to

Struan Jacobs

2000-01-01

369

Synchronization of fractional order chaotic systems  

E-print Network

The chaotic dynamics of fractional order systems begin to attract much attentions in recent years. In this brief report, we study the master-slave synchronization of fractional order chaotic systems. It is shown that fractional order chaotic systems can also be synchronized.

Chunguang Li; Xiaofeng Liao; Juebang Yu

2004-10-19

370

Control of Fractional-Order Chua's System  

E-print Network

This paper deals with feedback control of fractional-order Chua's system. The fractional-order Chua's system with total order less than three which exhibit chaos as well as other nonlinear behavior and theory for control of chaotic systems using sampled data are presented. Numerical experimental example is shown to verify the theoretical results.

I. Petras

2000-08-22

371

Chaos in a fractional order Chua's system  

Microsoft Academic Search

This brief studies the effects of fractional dynamics in chaotic systems. In particular, Chua's system is modified to include fractional order elements. By varying the total system order incrementally from 3.6 to 3.7, it is demonstrated that systems of “order” less than three can exhibit chaos as well as other nonlinear behavior. This effectively forces a clarification of the definition

Tom T. Hartley; Carl F. Lorenzo; Helen Killory Qammer

1995-01-01

372

Synchronization of fractional order chaotic systems  

Microsoft Academic Search

The chaotic dynamics of fractional order systems began to attract much attention in recent years. In this Brief Report, we study the master-slave synchronization of fractional order chaotic systems. It is shown that fractional order chaotic systems can also be synchronized.

Chunguang Li; Xiaofeng Liao; Juebang Yu

2003-01-01

373

Fractional order Fourier transform and Fourier optics  

Microsoft Academic Search

The electromagnetic field transfer from a spherical emitter to a spherical receiver is expressed through a fractional order Fourier transform. Given an emitter and a receiver, the order of the fractional transform is calculated as a function of their distance and their radii of curvature. The continuity of fractional Fourier transforms with respect to their orders corresponds to the continuity

Pierre Pellat-Finet; Georges Bonnet

1994-01-01

374

Order in Number, Monograph No. 3.  

ERIC Educational Resources Information Center

This monograph attempts to provide the teacher with examples, techniques, and tips for developing order in number. Topics covered include pre-number order and classification; beginning number activities; number lines; the 100-square counting chart; ordering the integers; fractional numbers; and games, counting rhymes, and other activities. A…

Beardsley, Leeh M.

375

20 CFR 655.121 - Job orders.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Job orders. 655.121 Section 655.121... Prefiling Procedures § 655.121 Job orders. (a) Area of intended employment...Certification, the employer must submit a job order, Form ETA-790, to the SWA...

2011-04-01

376

20 CFR 655.121 - Job orders.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Job orders. 655.121 Section 655.121... Prefiling Procedures § 655.121 Job orders. (a) Area of intended employment...Certification, the employer must submit a job order, Form ETA-790, to the SWA...

2010-04-01

377

20 CFR 655.121 - Job orders.  

...2014-04-01 2014-04-01 false Job orders. 655.121 Section 655.121... Prefiling Procedures § 655.121 Job orders. (a) Area of intended employment...Certification, the employer must submit a job order, Form ETA-790, to the SWA...

2014-04-01

378

20 CFR 655.121 - Job orders.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Job orders. 655.121 Section 655.121... Prefiling Procedures § 655.121 Job orders. (a) Area of intended employment...Certification, the employer must submit a job order, Form ETA-790, to the SWA...

2012-04-01

379

20 CFR 655.121 - Job orders.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Job orders. 655.121 Section 655.121... Prefiling Procedures § 655.121 Job orders. (a) Area of intended employment...Certification, the employer must submit a job order, Form ETA-790, to the SWA...

2013-04-01

380

Abel's Theorem Simplifies Reduction of Order  

ERIC Educational Resources Information Center

We give an alternative to the standard method of reduction or order, in which one uses one solution of a homogeneous, linear, second order differential equation to find a second, linearly independent solution. Our method, based on Abel's Theorem, is shorter, less complex and extends to higher order equations.

Green, William R.

2011-01-01

381

On perfect order subsets in finite groups  

Microsoft Academic Search

If $G$ is a finite group and $x\\\\in G$ then the set of all elements of $G$ having the same order as $x$ is called {\\\\em an order subset of $G$ determined by $x$} (see [2]). We say that $G$ is a {\\\\em group with perfect order subsets} or briefly, $G$ is a {\\\\em $POS$-group} if the number of elements

Nguyen Trong Tuan; Bui Xuan Hai

2010-01-01

382

Weak ordering—a new definition  

Microsoft Academic Search

A memory model for a shared memory, multiprocessor commonly and often implicitly assumed by programmers is that of sequential consistency. This model guarantees that all memory accesses will appear to execute atomically and in program order. An alternative model, weak ordering, offers greater performance potential. Weak ordering was first defined by Dubois, Scheurich and Briggs in terms of a set

Sarita V. Adve; Mark D. Hill

1990-01-01

383

Ordered Choices and Heterogeneity in Attribute Processing  

Microsoft Academic Search

A growing number of empirical studies involve the assessment of influences on a choice amongst ordered discrete alternatives. Ordered logit and probit models are well known, including extensions to accommodate random parameters and heteroscedasticity in unobserved variance. This paper extends the ordered choice random parameter model to permit random parameterisation of thresholds and decomposition to establish observed sources of systematic

William H. Greene; David A. Hensher

2010-01-01

384

Extended-range order in glasses  

SciTech Connect

A new type of order is identified in complex glasses, characterized by diffraction peaks at values of the wave vector below those typical of intermediate-range order. Combined neutron and anomalous x-ray diffraction studies of one glass exhibiting this behavior, vitreous rubidium germanate, indicate it to be associated with chemical ordering of the two cations with respect to each other.

Ellison, A.J.G.; Price, D.L.; Saboungi, M.L. [Argonne National Lab., IL (United States); Egami, T.; Hu, Rui-Zhong [Pennsylvania Univ., Philadelphia, PA (United States); Howells, W.S. [Rutherford Appleton Lab., Chilton (United Kingdom)

1994-03-01

385

DIPLOMA ORDER Office of the Registrar  

E-print Network

DIPLOMA ORDER Office of the Registrar The University of Texas at Dallas orders diplomas at least once each month. The fee for ordering an additional or replacement diploma is $10.00. There is an additional $25.00 fee for diplomas mailed to addresses outside the United States. If paying by check or money

O'Toole, Alice J.

386

The role of order in distributed programs  

NASA Technical Reports Server (NTRS)

The role of order in building distributed systems is discussed. It is the belief that a principle of event ordering underlies the wide range of operating systems mechanisms that were put forward for building robust distributed software. Stated concisely, this principle achieves correct distributed behavior by ordering classes of distributed events that conflict with one another. By focusing on order, simplified descriptions can be obtained and convincingly correct solutions to problems that might otherwise have looked extremely complex. Moreover, it is observed that there are a limited number of ways to obtain order, and that the choice made impacts greatly on performance.

Birman, Kenneth P.; Marzullo, Keith

1989-01-01

387

Why is order flow so persistent?  

E-print Network

Equity order flow is persistent in the sense that buy orders tend to be followed by buy orders and sell orders tend to be followed by sell orders. For equity order flow this persistence is extremely long-ranged, with positive correlations spanning thousands of orders, over time intervals of up to several days. Such persistence in supply and demand is economically important because it influences the market impact as a function of both time and size and because it indicates that the market is in a sense out of equilibrium. Persistence can be caused by two types of behavior: (1) Order splitting, in which a single investor repeatedly places an order of the same sign, or (2) herding, in which different investors place orders of the same sign. We develop a method to decompose the autocorrelation function into splitting and herding components and apply this to order flow data from the London Stock Exchange containing exchange membership identifiers. Members typically act as brokers for other investors, so that it is...

Toth, Bence; Lillo, Fabrizio; Farmer, J Doyne

2011-01-01

388

Binocular Combination of Second-Order Stimuli  

PubMed Central

Phase information is a fundamental aspect of visual stimuli. However, the nature of the binocular combination of stimuli defined by modulations in contrast, so-called second-order stimuli, is presently not clear. To address this issue, we measured binocular combination for first- (luminance modulated) and second-order (contrast modulated) stimuli using a binocular phase combination paradigm in seven normal adults. We found that the binocular perceived phase of second-order gratings depends on the interocular signal ratio as has been previously shown for their first order counterparts; the interocular signal ratios when the two eyes were balanced was close to 1 in both first- and second-order phase combinations. However, second-order combination is more linear than previously found for first-order combination. Furthermore, binocular combination of second-order stimuli was similar regardless of whether the carriers in the two eyes were correlated, anti-correlated, or uncorrelated. This suggests that, in normal adults, the binocular phase combination of second-order stimuli occurs after the monocular extracting of the second-order modulations. The sensory balance associated with this second-order combination can be obtained from binocular phase combination measurements. PMID:24404180

Zhou, Jiawei; Liu, Rong; Zhou, Yifeng; Hess, Robert F.

2014-01-01

389

First-order inflation. [in cosmology  

NASA Technical Reports Server (NTRS)

In the original proposal, inflation occurred in the process of a strongly first-order phase transition. This model was soon demonstrated to be fatally flawed. Subsequent models for inflation involved phase transitions that were second-order, or perhaps weakly first-order; some even involved no phase transition at all. Recently the possibility of inflation during a strongly first-order phase transition has been revived. In this paper, some models for first-order inflation are discussed, and unique signatures that result if inflation is realized in a first-order transition are emphasized. Some of the history of inflation is reviewed to demonstrate how first-order inflation differs from other models.

Kolb, Edward W.

1991-01-01

390

Solid-state molecular rotors with perdeuterated stators: mechanistic insights from biphenylene rotational dynamics in ordered and disordered crystal forms.  

PubMed

Samples of 4,4'-bis(3,3,3-tri-d(5)-phenylpropynyl)biphenyl 2, 9,10-bis(3,3,3-tri-d(5)-phenylpropynyl)anthracene 3, 1,4-bis(3,3,3-tri-d(5)-phenylpropynyl)naphthalene 4, and 4,4'-bis(3,3,3-tri-d(5)-phenylpropynyl)-1,1'-binaphthyl 5 were prepared via a Sonogashira coupling of 3,3,3-tri-d(5)-phenylpropyne 7 and the appropriate aryl dibromide. Single crystal X-ray diffraction structures were obtained for an o-xylene clathrate of 2 and for solvent-free crystals of 3. All four molecular rotors were characterized by CPMAS (13)C NMR experiments with varying contact times in order to determine whether the carbon signals of the central rotator group could be selectively enhanced and studied without interference or overlap of signals from the deuterated stator, which is insensitive to the {(1)H}-(13)C cross-polarization method. It was shown that the (13)C signals of the natural abundance rotator group can be selectively observed with short contact times (ca. 50 micros) without interference from other (13)C signals in the molecule. Variable-temperature CPMAS (13)C NMR studies with a crystalline o-xylene solvate of biphenylene rotor 2 suggested a 2-fold flipping process in the fast exchange regime, even at temperatures as low as 199 K (-74 degrees C). Indirect support for this was obtained by studies carried out with a disordered, solvent-free solid, obtained by fast precipitation from hexanes and dichloromethane, which displayed slower dynamics within the same temperature range with an activation energy of 8.7 kcal/mol and a pre-exponential factor of 4.9 x 10(9) s(-1). Confirmation of an exchange process in the megahertz regime for the crystalline solvate was obtained by variable-temperature quadrupolar echo (2)H NMR data acquired with samples prepared with a deuterated biphenylene rotator and a natural abundance stator. Although rotational exchange occurs in the solvated samples with a slightly lower barrier of 7.4 kcal/mol, the main difference with the precipitated solid comes from the pre-exponential factor, which is nearly 3 orders of magnitude greater with a value of 2.5 x 10(12) s(-1). On the basis of these differences, we speculate that efficient rotational motion in the solvated crystals may take advantage of long-range lattice vibrations that couple with molecular modes and that the lack of long-range order may be responsible for the low pre-exponential factor observed in the disordered crystals. PMID:20232842

O'Brien, Zachary J; Karlen, Steven D; Khan, Saeed; Garcia-Garibay, Miguel A

2010-04-16

391

Sixth order electron and muon (g-2)\\/2 from second order vacuum polarization insertion  

Microsoft Academic Search

We complete the analytic evaluation of sixth order contributions to electron and muon anomalous magnetic moments coming from second order vacuum polarization insertions into all the fourth order graphs. On leave from Istituto di Fisica dell'Università, Bologna.

Riccardo Barbieri; E. Remiddi

1974-01-01

392

78 FR 42787 - Anneri Izurieta; Conviction Reversal; Final Order Withdrawing Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...Final Order Withdrawing Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The U.S. Food and Drug Administration (FDA) is issuing an order, under the Federal Food, Drug, and Cosmetic Act (the...

2013-07-17

393

78 FR 42787 - Yuri Izurieta; Conviction Reversal; Final Order Withdrawing Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...Final Order Withdrawing Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The U.S. Food and Drug Administration (FDA) is issuing an order, under the Federal Food, Drug, and Cosmetic Act (the...

2013-07-17

394

Monte Carlo computer simulation of order-order kinetics in the L12-ordered Ni3Al binary system  

Microsoft Academic Search

The results of previous extensive experiments on gamma'-Ni3Al systems are interpreted and explained by means of Monte Carlo computer simulations based on the Glauber algorithm for vacancy mechanism of atomic migration in a superstructure. The complex character of the experimental ``order-order'' relaxation curves, as well as the theoretically predicted effect of vacancy ordering have been perfectly reproduced and analyzed in

P. Oramus; R. Kozubski; V. Pierron-Bohnes; M. C. Cadeville; W. Pfeiler

2001-01-01

395

Renormalization methods for higher order differential equations  

NASA Astrophysics Data System (ADS)

We adapt methodology of statistical mechanics and quantum field theory to approximate solutions to an arbitrary order ordinary differential equation boundary value problem by a second-order equation. In particular, we study equations involving the derivative of a double-well potential such as u? - ?u3 or -?u + 2u3. Using momentum (Fourier) space variables we average over short length scales and demonstrate that the higher order derivatives can be neglected within the first cumulant approximation, once length is properly renormalized, yielding an approximation to solutions of the higher order equation from the second order. The results are confirmed using numerical computations. Additional numerics confirm that the main role of the higher order derivatives is in rescaling the length.

Caginalp, Gunduz; Esenturk, Emre

2014-08-01

396

Variable-order fuzzy fractional PID controller.  

PubMed

In this paper, a new tuning method of variable-order fractional fuzzy PID controller (VOFFLC) is proposed for a class of fractional-order and integer-order control plants. Fuzzy logic control (FLC) could easily deal with parameter variations of control system, but the fractional-order parameters are unable to change through this way and it has confined the effectiveness of FLC. Therefore, an attempt is made in this paper to allow all the five parameters of fractional-order PID controller vary along with the transformation of system structure as the outputs of FLC, and the influence of fractional orders ? and ? on control systems has been investigated to make the fuzzy rules for VOFFLC. Four simulation results of different plants are shown to verify the availability of the proposed control strategy. PMID:25440947

Liu, Lu; Pan, Feng; Xue, Dingyu

2014-10-29

397

Time-fractional diffusion of distributed order  

E-print Network

The partial differential equation of Gaussian diffusion is generalized by using the time-fractional derivative of distributed order between 0 and 1, in both the Riemann-Liouville (R-L) and the Caputo (C) sense. For a general distribution of time orders we provide the fundamental solution, that is still a probability density, in terms of an integral of Laplace type. The kernel depends on the type of the assumed fractional derivative except for the single order case where the two approaches turn to be equivalent. We consider with some detail two cases of order distribution: the double-order and the uniformly distributed order. For these cases we exhibit plots of the corresponding fundamental solutions and their variance, pointing out the remarkable difference between the two approaches for small and large times.

Francesco Mainardi; Antonio Mura; Gianni Pagnini; Rudolf Gorenflo

2007-09-30

398

First-Order Ordinary Differential Equations  

Microsoft Academic Search

\\u000a First-order ordinary differential equations have some rather special properties, which result for the most part because they\\u000a can only contain a limited number of terms. In fact, all linear first-order ordinary differential equations can easily be\\u000a solved. This is in contrast to higher-order ordinary differential equations that become much more difficult to solve when,\\u000a for example, they contain variable coefficients.

Bill Goodwine

399

An overview of task order 10  

SciTech Connect

Task Order 10 formalizes a collaboration in high explosive pulsed power (HEPP) experiments between LANL and VNIIEF. The focus is the VNIIEF disk explosive magnetic generator (DEMG) technology. The task order outlines a sequence of tasks and deliverables culminating in an experiment which takes place in the US utilizing US explosives and a Russian DEMG. This talk summarizes task order 10. It gives a brief history and present status in terms of the proposed high pressure EOS experiment (ALT-3).

Rousculp, Christopher L [Los Alamos National Laboratory

2011-01-12

400

Two-dimensional order and disorder thermofields  

SciTech Connect

The main objective of this paper was to obtain the two-dimensional order and disorder thermal operators using the Thermofield Bosonization formalism. We show that the general property of the two-dimensional world according with the bosonized Fermi field at zero temperature can be constructed as a product of an order and a disorder variables which satisfy a dual field algebra holds at finite temperature. The general correlation functions of the order and disorder thermofields are obtained.

Belvedere, L. V. [Instituto de Fisica - Universidade Federal Fluminense, Av. Litora circumflex nea S/N, Boa Viagem Niteroi, CEP 24210-340 Rio de Janeiro (Brazil)

2006-11-15

401

Reduced-Order Models for MEMS Applications  

Microsoft Academic Search

We review the development of reduced-order models for MEMS devices. Based on their implementation procedures, we classify these reduced-order models into two broad categories: node and domain methods. Node methods use lower-order approximations of the system matrices found by evaluating the system equations at each node in the discretization mesh. Domain-based methods rely on modal analysis and the Galerkin method

ALI H. NAYFEH; MOHAMMAD I. YOUNIS; EIHAB M. ABDEL-RAHMAN

2005-01-01

402

Econometric models of limit-order executions  

Microsoft Academic Search

We develop and estimate an econometric model of limit-order execution times using survival analysis and actual limit-order data. We estimate versions for time-to-first-fill and time-to-completion for both buy and sell limit orders, and incorporate the effects of explanatory variables such as the limit price, limit size, bid\\/offer spread, and market volatility. Execution times are very sensitive to the limit price,

Andrew W. Lo; A. Craig MacKinlay; June Zhang

2002-01-01

403

Marketing Milk Under Federal Orders in Texas.  

E-print Network

ITIN 959 JULY 1960 llarketinff Milk un er Federal Orders in Texas order ZAIm includes Beckman county, Oklahoma. 3Also includes eight counties in Oklahoma. TEXAS AGRICULTURAL EXPERIMENT STATION R. D. LEWIS, DIRECTOR. COLLEGE STATION, TEXAS... SUMMARY Some Texas dairy farmers have been market- ing milk under federal orders since October 1951. In December 1959, 5,270, or 68 percent of Texas producers sold milk under the seven federal or- ders. In 1959 these producers marketed more than 1...

Stelly, Randall

1960-01-01

404

The Twelve Soil Orders - Soil Taxonomy  

NSDL National Science Digital Library

This University of Idaho website discusses the twelve orders of soils, and provides images that illustrate the distribution, properties, and use of the soil orders. It provides general information on each of the twelve orders with a description, a U.S. map showing soil locations, and pictures of the soil type. A Global Distribution Map indicates locations of each soil type throughout the world.

405

EHV high-phase-order power transmission  

SciTech Connect

This report is divided into the following topics: benefits of high phase order, EHV high phase order alternatives to UHV 3 phase transmission, mechanical design of high phase order structures, transmission line economics, economics of line terminals, combined economics of lines and stations, single pole switching, neutral shift, rate of rise of recovery voltage on circuit breakers, gradient unbalance due to ground plane, insulation design of HPO systems, line optimization results, and sample line impedances. (DLC)

Douglass, D.A.; Kallaur, E.; Stewart, J.R.

1983-09-01

406

Elementary excitations in uranium dioxide: Unravelling the tangle  

NASA Astrophysics Data System (ADS)

In solids with d- and f-electrons, under certain conditions the orbitals align to form an ordered structure. Collective excitations breaking this arrangement can take the form of oscillations of electric quadrupoles, the so-called quadrupolar waves. These represent a propagating pattern of charge densities implying a modulation of quadrupolar moments. Quadrupolar waves constitute a major component of the dynamics of uranium dioxide in its magneto-quadrupolar ordered phase. Together with spin-waves and phonons, these produce a very complex spectrum of elementary excitations having hybrid character over most of the Brillouin zone. Although neutron scattering spectra only reveal the tip of the iceberg of this spectrum, its complete and detailed modelling is needed to understand such experiments. Distinct roles of Jahn-Teller and superexchange mechanisms as sources of quadrupolar interactions can be clearly identified by such modelling. xml:lang="fr"

Santini, Paolo

2014-08-01

407

CCII based fractional filters of different orders  

PubMed Central

This paper aims to generalize the design of continuous-time filters to the fractional domain with different orders and validates the theoretical results with two different CCII based filters. In particular, the proposed study introduces the generalized formulas for the previous fractional-order analysis of equal orders. The fractional-order filters enhance the design flexibility and prove that the integer-order performance is a very narrow subset from the fractional-order behavior due to the extra degrees of freedom. The general fundamentals of these filters are presented by calculating the maximum and minimum frequencies, the half power frequency and the right phase frequency which are considered a critical issue for the filter design. Different numerical solutions for the generalized fractional order low pass filters with two different fractional order elements are introduced and verified by the circuit simulations of two fractional-order filters: Kerwin–Huelsman–Newcomb (KHN) and Tow-Tomas CCII-based filters, showing great matching.

Soltan, Ahmed; Radwan, Ahmed G.; Soliman, Ahmed M.

2013-01-01

408

Distributed order fractional sub-diffusion  

E-print Network

A distributed order fractional diffusion equation is considered. Distributed order derivatives are fractional derivatives that have been integrated over the order of the derivative within a given range. In this paper sub-diffusive cases are considered. That is, the order of the time derivative ranges from zero to one. The equation is solved for Dirichlet, Neumann, and Cauchy boundary conditions. The time dependence for each of the three cases is found to be a functional of the diffusion parameter. This functional is shown to have decay properties. Upper and lower bounds are computed for the functional. Examples are also worked out for comparative decay rates.

Mark Naber

2003-11-25

409

Reduction of fourth order ordinary differential equations to second and third order Lie linearizable forms  

NASA Astrophysics Data System (ADS)

Meleshko presented a new method for reducing third order autonomous ordinary differential equations (ODEs) to Lie linearizable second order ODEs. We extended his work by reducing fourth order autonomous ODEs to second and third order linearizable ODEs and then applying the Ibragimov and Meleshko linearization test for the obtained ODEs. The application of the algorithm to several ODEs is also presented.

Dutt, Hina M.; Qadir, Asghar

2014-08-01

410

Robust stability region of fractional order PI controller for fractional order interval plant  

Microsoft Academic Search

In this article, by using the fractional order PI controller, we propose a simple and effective method to compute the robust stability region for the fractional order linear time-invariant plant with interval type uncertainties in both fractional orders and relevant coefficients. The presented method is based on decomposing the fractional order interval plant into several vertex plants using the lower

Taonian Liang; Jianjun Chen; Huihuang Zhao

2012-01-01

411

TO SUBMIT ORDER, Click on link below and enter numbers for access. ORDER FACULTY REGALIA  

E-print Network

departmental credit card by calling our office at 970.663.2668. Payment will be processed prior to orderTO SUBMIT ORDER, Click on link below and enter numbers for access. ORDER FACULTY REGALIA Customer Number: 05000206002 Order Number: 3201933 Using the drop down menu, find your name, click on it then hit

412

SECOND{ORDER AND HIGHER{ORDER PERTURBATIONS OF TRAVEL TIME IN ISOTROPIC AND ANISOTROPIC MEDIA  

E-print Network

SECOND{ORDER AND HIGHER{ORDER PERTURBATIONS OF TRAVEL TIME IN ISOTROPIC AND ANISOTROPIC MEDIA Lud derivatives of travel time with respect to model parameters are re- ferred to as perturbations. Explicit equations for the second{order and higher{order perturbations of travel time in both isotropic

Cerveny, Vlastislav

413

Fractional-order system identification based on continuous order-distributions  

Microsoft Academic Search

Abstract This paper discusses the identi cation of fractional- and integer-order systems using the concept of continuous order- distribution. Based on the ability to de ne systems using continuous order-distributions, it is shown that frequency domain system identi cation can be performed. Least-squares techniques are applied to discretized order-distributions. Methods are presented for properly discretizing the order-distribution. ? 2003 Published

Tom T. Hartley; Carl F. Lorenzo

2003-01-01

414

Revised October 2008 Business Card Order Form  

E-print Network

Revised October 2008 Business Card Order Form Please fill out the following information as how it should appear on the business card: * Indicates a required field. * First and Last Name) Peace River - Liard (Fort St. John) South Central (Quesnel) Tape Sample Business Card Here Order

Northern British Columbia, University of

415

Low-order IIR filter bank design  

Microsoft Academic Search

The advantage of IIR filters over FIR ones is that the former require a much lower order to obtain the desired response specifications. However, the existing deterministic techniques for IIR filter bank design based on heuristic usually lead to too high order IIR filters and thus cannot be practically used. In this paper, we propose new method to solve the

H. D. Tuan; T. T. Son; T. Q. Nguyen

2003-01-01

416

An Approximate Theory of Order in Alloys  

Microsoft Academic Search

Short-range order parameters alphai are defined to express the interaction of a given atom in an alloy with the atoms of the ith shell of atoms surrounding it. From simple thermodynamic reasoning, involving a certain degree of approximation, equations relating the alphai with energy terms and the temperature are derived. Equations for the long-range order parameter, S, are obtained by

J. M. Cowley

1950-01-01

417

Fractional-order diffusion-wave equation  

Microsoft Academic Search

The fractional-order diffusion-wave equation is an evolution equation of order ? ? (0, 2] which continues to the diffusion equation when ? ? 1 and to the wave equation when ? ? 2. We prove some properties of its solution and give some examples. We define a new fractional calculus (negative-direction fractional calculus) and study some of its properties. We

Ahmed M. A. El-Sayed

1996-01-01

418

Design of fractional order digital FIR differentiators  

Microsoft Academic Search

In this paper, the design of a fractional order FIR differentiator is investigated. First, the fractional derivative of the power function is defined. Then, the impulse response of the fractional order differentiator is obtained by solving linear equations of the Vandermonde form. Finally, one example is used to demonstrate that the fractional derivatives of digital signals are easily computed by

Chien-Cheng Tseng

2001-01-01

419

Identification of Fractional-Order Dynamical Systems  

Microsoft Academic Search

This contribution deals with identification of fractional-order dynamical systems. We consider systems whose mathematical description is a three-member differential equation in which the orders of derivatives can be real numbers. We give a discretization method and a numerical solution of differential equations of this type. An experimental method of identification is given which is based on evaluation of transfer characteristics.

L. Dorcak; V. Lesko; I. Kostial

2002-01-01

420

High order curvature Adaptive Optics revisited  

Microsoft Academic Search

High dynamic range imaging is defined as the search for very faint objects around bright ones. This pushes requirements on every aspect of telescope and instrument design. Coronography (lyot and phase), high order adaptive optics, apodised pupils may all have a role to play in this endeavor. High order adaptive optics systems have conventionnaly been thought of as Shack-Hartman\\/piezostack devices

Olivier Lai

2002-01-01

421

78 FR 13068 - Richard Stowell: Debarment Order  

Federal Register 2010, 2011, 2012, 2013

...FDA-2012-N-0714] Richard Stowell: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION...SUMMARY: The U.S. Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and Cosmetic Act (FD&C...

2013-02-26

422

Few Fractional Order Derivatives and Their Computations  

ERIC Educational Resources Information Center

This work presents an introductory development of fractional order derivatives and their computations. Historical development of fractional calculus is discussed. This paper presents how to obtain computational results of fractional order derivatives for some elementary functions. Computational results are illustrated in tabular and graphical…

Bhatta, D. D.

2007-01-01

423

High Order Strong Stability Preserving Time Discretizations  

Microsoft Academic Search

Strong stability preserving (SSP) high order time discretizations were developed to ensure nonlinear stability properties necessary in the numerical solution of hyperbolic par- tial differential equations with discontinuous solutions. SSP methods preserve the strong sta- bility properties---in any norm, seminorm or convex functional---of the spatial discretization coupled with first order Euler time stepping. This paper describes the development of SSP

Sigal Gottlieb; David I. Ketcheson; Chi-Wang Shu

2009-01-01

424

Texas Union Pizza Order Form ROOM RESERVED ______________________________________________________  

E-print Network

#12;#12;Texas Union Pizza Order Form ROOM RESERVED: ________________________________________________________________________________________________ ________________________________________________________________________________________________ ________________________________________________________________________________________________ ________________________________________________________________________________________________ ________________________________________________________________________________________________ ________________________________________________________________________________________________ ________________________________________________________________________________________________ ________________________________________________________________________________________________ Pick-up All orders are to be picked up at the Texas Union Hospitality Center desk in the south end West with the Texas Union Policies and Procedures. I understand that I will be held responsible for any debts incurred

Jefferys, William

425

Science Orders Systems and Operations Manual.  

ERIC Educational Resources Information Center

This manual describes the implementation and operation of SCIENCE ORDERS, an online orders management system used by the Science and Technology Department of Newman Library at Virginia Polytechnic Institute and State University. Operational since January 1985, the system is implemented using the SPIRES database management system and is used to (1)…

Kriz, Harry M.

426

First order common knowledge logics Frank Wolter  

E-print Network

(believes) ''' and ``it is common knowledge among the agents in M that ''', respectively. PropositionalFirst order common knowledge logics Frank Wolter Institut f¨ur Informatik, Universit¨at Leipzig #12; Abstract In this paper we investigate first order common knowledge logics; i.e., modal epistemic

Wolter, Frank

427

Exploring Partial Order of European Countries  

ERIC Educational Resources Information Center

Partial Order Theory has been recently more and more employed in applied science to overcome the intrinsic disadvantage hidden in aggregation, if a multiple attribute system is available. Despite its numerous positive features, there are many practical cases where the interpretation of the partial order can be rather troublesome. In these cases…

Annoni, Paola; Bruggemann, Rainer

2009-01-01

428

Ordered Diagnosis c Springer-Verlag  

E-print Network

be used to perform diagnosis [21,3]. Rules in the fault model specify cause-effect relationshipsOrdered Diagnosis c Springer-Verlag Davy Van Nieuwenborgh and Dirk Vermeir Dept. of Computer fault model, between the various knowledge sources. It turns out that the seman- tics for ordered logic

Vermeir, Dirk

429

Seismic imaging using higher order statistics  

E-print Network

the resulting algorithm is a cross-correlation (second order statistics) operation whose region of support is limited to the bandwidth of the source signal. This is not the case for non-vanishing higher order cumulates where the support region can be extended...

Srinivasan, Karthik

2012-06-07

430

Fuzzy Multiple Ordering Criteria for Examination Timetabling  

E-print Network

Fuzzy Multiple Ordering Criteria for Examination Timetabling Hishammuddin Asmuni, Edmund K. Burke exams by simultaneously considering two ordering criteria using a fuzzy expert system is presented enroll- ment are considered. The fuzzy weight of an exam is used to represent how dif- ficult

Aickelin, Uwe

431

Nematic Ordered Cellulose: Its Structure and Properties  

Microsoft Academic Search

The authors developed a unique form of ?-glucan association, “nematic ordered cellulose” (NOC) that is molecularly ordered, yet noncrystalline. NOC has unique characteristics; in particular, its surface properties provide with a function of tracks or scaffolds for regulated movements and fiber production of Acetobacter xylinum (=Gluconacetobacter xylinus), which produces cellulose ribbon-like nanofibers with 40–60 nm in width and moves due

Tetsuo Kondo

432

Pedophilia, Sexual Orientation, and Birth Order  

Microsoft Academic Search

This study extended research on birth order and erotic preferences by examining birth order in a sample of pedophiles. Charts of 338 pedophiles, assessed from 1980–1994 in the Behavioural Sexology Department of the Clarke Institute of Psychiatry in Toronto, were reviewed for family–demographic information. In total, 170 (57 heterosexual pedophiles, 68 homosexual pedophiles, and 45 bisexual pedophiles) of these men

Anthony F. Bogaert; Scott Bezeau; Michael Kuban; Ray Blanchard

1997-01-01

433

40 CFR 90.503 - Test orders.  

Code of Federal Regulations, 2010 CFR

...SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Selective Enforcement Auditing § 90.503 Test orders. (a) The Administrator shall...shall not issue to a manufacturer more Selective Enforcement Auditing (SEA) test orders than an annual limit determined by...

2010-07-01

434

A. METHOD OF PAYMENT: B. ORDERING  

E-print Network

Ground Shipping FREE within Continental US $ Name: Address: Address: Address: Phone No: Email: D. MAILING: Vanderbilt University Attn: Lynn Davies/PALS ORDERS PMB 228 (Peabody ) Phone: (615) 343-4782 110 Magnolia payable to VANDERBILT UNIVERSITY. Payment by purchase order is expected within 45 days of shipment. We do

Palmeri, Thomas

435

A. METHOD OF PAYMENT: B. ORDERING  

E-print Network

: Phone No: Email: D. MAILING: Vanderbilt University Attn: Lynn Davies/PALS ORDERS PMB 228 (Peabody ) Phone: (615) 343-4782 110 Magnolia Circle, Suite 418 Fax: (615) 936-5803 Nashville, TN 37203-5701 E or CHECKS payable to VANDERBILT UNIVERSITY. Payment by purchase order is expected within 45 days of shipment

Palmeri, Thomas

436

Higher-Order Neural Networks Recognize Patterns  

NASA Technical Reports Server (NTRS)

Networks of higher order have enhanced capabilities to distinguish between different two-dimensional patterns and to recognize those patterns. Also enhanced capabilities to "learn" patterns to be recognized: "trained" with far fewer examples and, therefore, in less time than necessary to train comparable first-order neural networks.

Reid, Max B.; Spirkovska, Lilly; Ochoa, Ellen

1996-01-01

437

Axiomatizing first order consequences in dependence logic  

E-print Network

Axiomatizing first order consequences in dependence logic Juha Kontinen Jouko V¨a¨an¨anen May 18, 2012 Abstract Dependence logic, introduced in [8], cannot be axiomatized. However, first-order consequences of dependence logic sentences can be axiomatized, and this is what we shall do in this paper. We

Väänänen, Jouko

438

A New Approach to an Old Order.  

ERIC Educational Resources Information Center

Explains the difficulties middle school students face in algebra regarding the order of operations. Describes a more visual approach to teaching the order of operations so that students can better solve complex problems and be better prepared for the rigors of algebra. (YDS)

Rambhia, Sanjay

2002-01-01

439

Birth Order, Family Size and Educational Attainment  

ERIC Educational Resources Information Center

This paper investigates the effect of family size and birth order on educational attainment. An instrumental variables approach is used to identify the effect of family size. Instruments for the number of children are twins at last birth and the sex mix of the first two children. The effect of birth order is identified, by examining the relation…

de Haan, Monique

2010-01-01

440

Higher-order elastics and elastic hulls  

NASA Astrophysics Data System (ADS)

By higher-order elastics we mean solutions of the problem to minimize integrals of quadratic forms of curvatures of multidimensional curves. Differential equations of second-order elastics (minimizing a quadratic form of the curvature and torsion of the curve) are obtained. Surfaces minimizing integrals of the squared Gaussian curvature are found.

Osipov, Yu. S.; Zelikin, M. I.

2012-04-01

441

A Note on Canonical Word Order  

ERIC Educational Resources Information Center

In this brief report, we summarize the results of an experiment on the interpretation of English word order patterns by adult Korean- and Japanese-speaking second language learners. Our results suggest that a direct relationship between a construction's word order and the structure of the corresponding event has a greater facilitative effect on…

O'Grady, William; Yamashita, Yoshie; Lee, Sun-Young

2005-01-01

442

Constraints on topological order in Mott Insulators  

E-print Network

We point out certain symmetry induced constraints on topological order in Mott Insulators (quantum magnets with an odd number of spin $\\tfrac{1}{2}$ per unit cell). We show, for example, that the double semion topological order is incompatible with time reversal and translation symmetry in Mott insulators. This sharpens the Hastings-Oshikawa-Lieb-Schultz-Mattis theorem for 2D quantum magnets, which guarantees that a fully symmetric gapped Mott insulator must be topologically ordered, but is silent on which topological order is permitted. An application of our result is the Kagome lattice quantum antiferromagnet where recent numerical calculations of entanglement entropy indicate a ground state compatible with either toric code or double semion topological order. Our result rules out the latter possibility.

Michael P. Zaletel; Ashvin Vishwanath

2014-10-10

443

Verbal medication orders in the OR.  

PubMed

Medication errors are the fourth most commonly reported sentinel event, and changes in practice are needed to provide a safe environment for patients in the OR. Existing measures for preventing medication errors in the OR have focused on labeling medication containers on and off the sterile field. Very little attention, however, has been given to the potential for errors caused by verbal orders in the OR or to developing processes to prevent such errors. Simple solutions for improving the safety of verbal medication orders include instituting a read-back system in which verbal orders are written on a dry-erase board and verified by the ordering physician, requesting clarification of questionable orders, and reducing distractions in the OR. PMID:17931542

Hendrickson, Thomas

2007-10-01

444

Arbitrary order permanent Cartesian multipolar electrostatic interactions.  

PubMed

Recently, there has been a concerted effort to implement advanced classical potential energy surfaces by adding higher order multipoles to fixed point charge electrostatics in a bid to increase the accuracy of simulations of condensed phase systems. One major hurdle is the unwieldy nature of the expressions which in part has limited developers mostly to including only dipoles and quadrupoles. In this paper, we present a generalization of the Cartesian formulation of electrostatic multipolar interactions that enables the specification of an arbitrary order of multipoles. Specifically, we derive formulas for arbitrary order implementation of the particle mesh Ewald method and give a closed form formula for the stress tensor in the reciprocal space. In addition, we provide recurrence relations for common electrostatic potentials employed in molecular simulations, which allows for the generalization to arbitrary order and guarantees a computational cost that scales as O(p(3)) for Cartesian multipole interactions of order p. PMID:25612699

Boateng, H A; Todorov, I T

2015-01-21

445

Order in Gravitation Potentially Linked to Evolution  

NASA Astrophysics Data System (ADS)

Darwin, in the concluding remark of his text, On the Origin of Species (1859), referred to ``the fixed law of gravity'', which implies an assumption that the gravitational constant and the Newtonian the inverse square logic are potentially fixed. Therefore, they cannot influence evolution. My substantiation of the Dirac's Large Number Hypothesis (LNH) (In version 1 of http://www.arXiv.org/pdf/physics/0210040) predicting the decreasing value of gravitational constant theorizes that all coupling constants are increasing with time. This is also backed by the recent observations. Consequently, it is logical that the orderly increase of coupling constants imparts an orderly influence on mutations assumed uninfluenced otherwise. This orderly influence is unidirectional, clearly in the direction of increasing intelligence, looking at the evolutionary history, whether or not in the sense of a religion. On the horizon, I see that the order in gravitation is linked to the order in entropy as well.

Goradia, Shantilal

2006-04-01

446

Finding Higher Order Differentials of MISTY1  

NASA Astrophysics Data System (ADS)

MISTY1 is a 64-bit block cipher that has provable security against differential and linear cryptanalysis. MISTY1 is one of the algorithms selected in the European NESSIE project, and it is recommended for Japanese e-Government ciphers by the CRYPTREC project. In this paper, we report on 12th order differentials in 3-round MISTY1 with FL functions and 44th order differentials in 4-round MISTY1 with FL functions both previously unknown. We also report that both data complexity and computational complexity of higher order differential attacks on 6-round MISTY1 with FL functions and 7-round MISTY1 with FL functions using the 46th order differential can be reduced to as much as 1/22 of the previous values by using multiple 44th order differentials simultaneously.

Tsunoo, Yukiyasu; Saito, Teruo; Kawabata, Takeshi; Nakagawa, Hirokatsu

447

Odd orders in Shor's factoring algorithm  

NASA Astrophysics Data System (ADS)

Shor's factoring algorithm (SFA) finds the prime factors of a number, $N=p_1 p_2$, exponentially faster than the best known classical algorithm. Responsible for the speed-up is a subroutine called the quantum order finding algorithm (QOFA) which calculates the order -- the smallest integer, $r$, satisfying $a^r \\mod N =1$, where $a$ is a randomly chosen integer coprime to $N$ (meaning their greatest common divisor is one, $\\gcd(a, N) =1$). Given $r$, and with probability not less than $1/2$, the factors are given by $p_1 = \\gcd (a^{\\frac{r}{2}} - 1, N)$ and $p_2 = \\gcd (a^{\\frac{r}{2}} + 1, N)$. For odd $r$ it is assumed the factors cannot be found (since $a^{\\frac{r}{2}}$ is not generally integer) and the QOFA is relaunched with a different value of $a$. But a recent paper [E. Martin-Lopez: Nat Photon {\\bf 6}, 773 (2012)] noted that the factors can sometimes be found from odd orders if the coprime is square. This raises the question of improving SFA's success probability by considering odd orders. We show that an improvement is possible, though it is small. We present two techniques for retrieving the order from apparently useless runs of the QOFA: not discarding odd orders; and looking out for new order finding relations in the case of failure. In terms of efficiency, using our techniques is equivalent to avoiding square coprimes and disregarding odd orders, which is simpler in practice. Even still, our techniques may be useful in the near future, while demonstrations are restricted to factoring small numbers. The most convincing demonstrations of the QOFA are those that return a non-power-of-two order, making odd orders that lead to the factors attractive to experimentalists.

Lawson, Thomas

2015-01-01

448

Fourth order difference methods for hyperbolic IBVP's  

NASA Technical Reports Server (NTRS)

Fourth order difference approximations of initial-boundary value problems for hyperbolic partial differential equations are considered. We use the method of lines approach with both explicit and compact implicit difference operators in space. The explicit operator satisfies an energy estimate leading to strict stability. For the implicit operator we develop boundary conditions and give a complete proof of strong stability using the Laplace transform technique. We also present numerical experiments for the linear advection equation and Burgers' equation with discontinuities in the solution or in its derivative. The first equation is used for modeling contact discontinuities in fluid dynamics, the second one for modeling shocks and rarefaction waves. The time discretization is done with a third order Runge-Kutta TVD method. For solutions with discontinuities in the solution itself we add a filter based on second order viscosity. In case of the non-linear Burger's equation we use a flux splitting technique that results in an energy estimate for certain different approximations, in which case also an entropy condition is fulfilled. In particular we shall demonstrate that the unsplit conservative form produces a non-physical shock instead of the physically correct rarefaction wave. In the numerical experiments we compare our fourth order methods with a standard second order one and with a third order TVD-method. The results show that the fourth order methods are the only ones that give good results for all the considered test problems.

Gustafsson, Bertil; Olsson, Pelle

1994-01-01

449

Specific RNA binding to ordered phospholipid bilayers  

PubMed Central

We have studied RNA binding to vesicles bounded by ordered and disordered phospholipid membranes. A positive correlation exists between bilayer order and RNA affinity. In particular, structure-dependent RNA binding appears for rafted (liquid-ordered) domains in sphingomyelin-cholesterol-1,2-dioleoyl-sn-glycero-3-phosphocholine vesicles. Binding to more highly ordered gel phase membranes is stronger, but much less RNA structure-dependent. All modes of RNA-membrane association seem to be electrostatic and headgroup directed. Fluorometry on 1,2-dimyristoyl-sn-glycero-3-phosphocholine liposomes indicates that bound RNA broadens the gel-fluid melting transition, and reduces lipid headgroup order, as detected via fluorometric measurement of intramembrane electric fields. RNA preference for rafted lipid was visualized and confirmed using multiple fluorophores that allow fluorescence and fluorescence resonance energy transfer microscopy on RNA molecules closely associated with ordered lipid patches within giant vesicles. Accordingly, both RNA structure and membrane order could modulate biological RNA–membrane interactions. PMID:16641318

Janas, Tadeusz; Janas, Teresa; Yarus, Michael

2006-01-01

450

Enhanced Icosahedral Order in Supercooled Liquid Iron  

NASA Astrophysics Data System (ADS)

As part of a study of metallic glass-forming ability, we perform first-principles molecular dynamics simulations of supercooled liquid Iron. Analyzing the results according to the icosahedral order parameter W6, we find that Iron exhibits enhanced icosahedral order compared with supercooled Copper and compared with dense random packing. Voronoi analysis confirms the enhanced order is in the form of 13-atom icosahedral clusters as well as characteristic Frank-Kasper type disclinated icosahedra. Upon further cooling the sample crystallizes to a BCC lattice, with the icosahedra clustering to form a novel point defect.

Ganesh, P.; Widom, Mike

2007-03-01

451

5 Dice: Order of Operations Game  

NSDL National Science Digital Library

This math app intended for upper elementary students using the addition and subtraction level and middle school students using all four operations helps players practice their order of operations. This interactive game encourages students to use higher order thinking to use the five numbers and given operations to solve the "target" number by working backwards given the answer but not the equation. The best feature about this math game is that teachers are able to receive immediate feedback of their studentsâ progress through email. Students do not have to provide an email address in order to play.

Holladay, Josh

2013-01-31

452

Generalized higher-order nonlinear energy operators.  

PubMed

We extend and generalize the Teager-Kaiser [in Proceedings of IEEE International Conference on Acoustics, Speech, and Signal Processing (1993), Vol. 3, p. 149] and the higher-order differential energy operators [IEEE Signal Process. Lett.2, 152 (1995)] to a large class of operators called higher-order energy operators. We show that for AM-FM signal demodulation, the introduced partial derivative orders have to satisfy certain conditions. These operators are parameterized for local processing of AM-FM signals. The operators are illustrated using synthetic signals and a real signal from light scanning interferometry. PMID:18059924

Salzenstein, Fabien; Boudraa, Abdel-Ouahab; Cexus, Jean-Christophe

2007-12-01

453

Roughness in Lattice Ordered Effect Algebras  

PubMed Central

Many authors have studied roughness on various algebraic systems. In this paper, we consider a lattice ordered effect algebra and discuss its roughness in this context. Moreover, we introduce the notions of the interior and the closure of a subset and give some of their properties in effect algebras. Finally, we use a Riesz ideal induced congruence and define a function e(a, b) in a lattice ordered effect algebra E and build a relationship between it and congruence classes. Then we study some properties about approximation of lattice ordered effect algebras. PMID:25170523

Xin, Xiao Long; Hua, Xiu Juan; Zhu, Xi

2014-01-01

454

Word Order Variables in Patzun Kaqchikel  

E-print Network

is marked with the prefix y- or n-, while the completive aspect is marked with the prefix x- as shown in (5). (5) a. yiin y-at-in-tz’eet rat I incom-2sA-1sE-see you “I see you.” b. rjah... with the previous analysis of word orders in (Patzicia) Kaqchikel by Broadwell (2000).2 In Patzun Kaqchikel, in intransitive clauses, either SV word order or VS word order is possible in statements and questions. (1) a. ri n-tz...

Kim, Sok-Ju

2011-10-03

455

A Dynamic-Order Fractional Dynamic System  

E-print Network

Multi-system interaction is an important and difficult problem in physics. Motivated by the experimental result of an electronic circuit element "Fractor", we introduce the concept of dynamic-order fractional dynamic system, in which the differential-order of a fractional dynamic system is determined by the output signal of another dynamic system. The new concept offers a comprehensive explanation of physical mechanism of multi-system interaction. The properties and potential applications of dynamic-order fractional dynamic systems are further explored with the analysis of anomalous relaxation and diffusion processes.

HongGuang Sun; Hu Sheng; YangQuan Chen; Wen Chen; ZhongBo Yu

2013-04-09

456

Thermal Conductivity of Ordered Molecular Water  

SciTech Connect

We use molecular dynamics simulation to investigate thermal transport characteristics of water with various degree of orientational and translational order induced by the application of an electric field. We observe that orientational ordering of the water dipole moments has a minor effect on the thermal conductivity. However, electric-field induced crystallization and associated translational order results in approximately a 3-fold increase of thermal conductivity with respect to the base water, i.e., to values comparable with those characterizing ice crystal structures.

W Evans; J Fish; P Keblinski

2006-02-16

457

Magnetic fields from second-order interactions  

E-print Network

It is well known that when two types of perturbations interact in cosmological perturbation theory, the interaction may lead to the generation of a third type. In this article we discuss the generation of magnetic fields from such interactions. We determine conditions under which the interaction of a first-order magnetic field with a first-order scalar-or vector-, or tensor-perturbations would lead to the generation of second order magnetic field. The analysis is done in a covariant-index-free approach, but could be done in the standard covariant indexed-approach.

Bob Osano

2014-03-21

458

Make Your Own (Order of Operations)  

NSDL National Science Digital Library

To give them practice with order of operations, students make up and solve their own order of operations problems. This activity can be done two ways. 1. Students get into groups of two or three and make up about 3 different type of order of operations problems and then solve each of them. 2. Each student finds a partner, creates their own question, and trades it with their partner for them to try. Then they grade each other's work. Either way, they get extra practice, hopefully catch their mistakes with some help from another student, and take a more active approach to problem solving.

2010-01-01

459

Ordered mesoporous metal oxides: synthesis and applications.  

PubMed

Great progress has been made in the preparation and application of ordered mesoporous metal oxides during the past decade. However, the applications of these novel and interesting materials have not been reviewed comprehensively in the literature. In the current review we first describe different methods for the preparation of ordered mesoporous metal oxides; we then review their applications in energy conversion and storage, catalysis, sensing, adsorption and separation. The correlations between the textural properties of ordered mesoporous metal oxides and their specific performance are highlighted in different examples, including the rate of Li intercalation, sensing, and the magnetic properties. These results demonstrate that the mesoporosity has a direct impact on the properties and potential applications of such materials. Although the scope of the current review is limited to ordered mesoporous metal oxides, we believe that the information may be useful for those working in a number of fields. PMID:22653082

Ren, Yu; Ma, Zhen; Bruce, Peter G

2012-07-21

460

5 CFR 2638.402 - Corrective orders.  

Code of Federal Regulations, 2011 CFR

...orders. 2638.402 Section 2638.402 Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Correction of Executive Branch...

2011-01-01

461

5 CFR 2638.402 - Corrective orders.  

Code of Federal Regulations, 2013 CFR

...orders. 2638.402 Section 2638.402 Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Correction of Executive Branch...

2013-01-01

462

5 CFR 2638.402 - Corrective orders.  

...orders. 2638.402 Section 2638.402 Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Correction of Executive Branch...

2014-01-01

463

5 CFR 2638.402 - Corrective orders.  

Code of Federal Regulations, 2012 CFR

...orders. 2638.402 Section 2638.402 Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Correction of Executive Branch...

2012-01-01

464

5 CFR 2638.402 - Corrective orders.  

Code of Federal Regulations, 2010 CFR

...orders. 2638.402 Section 2638.402 Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Correction of Executive Branch...

2010-01-01

465

45 CFR 32.6 - Withholding order.  

Code of Federal Regulations, 2010 CFR

...to Employer & Important Notice to Employer,” an SF-329B “Wage Garnishment Order,” an SF-329C “Wage Garnishment Worksheet,” and an SF-329D “Employer Certification,” to the debtor's employer within 30 days after the debtor fails to...

2010-10-01

466

45 CFR 32.6 - Withholding order.  

Code of Federal Regulations, 2012 CFR

...to Employer & Important Notice to Employer,” an SF-329B “Wage Garnishment Order,” an SF-329C “Wage Garnishment Worksheet,” and an SF-329D “Employer Certification,” to the debtor's employer within 30 days after the debtor fails to...

2012-10-01

467

21 CFR 1301.46 - Final order.  

Code of Federal Regulations, 2011 CFR

...Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE REGISTRATION OF MANUFACTURERS, DISTRIBUTORS, AND DISPENSERS OF CONTROLLED SUBSTANCES Hearings § 1301.46 Final order. As soon as practicable after the presiding...

2011-04-01

468

21 CFR 1301.46 - Final order.  

Code of Federal Regulations, 2010 CFR

...Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE REGISTRATION OF MANUFACTURERS, DISTRIBUTORS, AND DISPENSERS OF CONTROLLED SUBSTANCES Hearings § 1301.46 Final order. As soon as practicable after the presiding...

2010-04-01

469

21 CFR 1301.46 - Final order.  

...Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE REGISTRATION OF MANUFACTURERS, DISTRIBUTORS, AND DISPENSERS OF CONTROLLED SUBSTANCES Hearings § 1301.46 Final order. As soon as practicable after the presiding...

2014-04-01

470

21 CFR 1301.46 - Final order.  

Code of Federal Regulations, 2012 CFR

...Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE REGISTRATION OF MANUFACTURERS, DISTRIBUTORS, AND DISPENSERS OF CONTROLLED SUBSTANCES Hearings § 1301.46 Final order. As soon as practicable after the presiding...

2012-04-01

471

21 CFR 1301.46 - Final order.  

Code of Federal Regulations, 2013 CFR

...Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE REGISTRATION OF MANUFACTURERS, DISTRIBUTORS, AND DISPENSERS OF CONTROLLED SUBSTANCES Hearings § 1301.46 Final order. As soon as practicable after the presiding...

2013-04-01

472

Theoretical study on high order interior tomography  

PubMed Central

In this paper, we study a new type of high order interior problems characterized by high order differential phase shift measurement. This problem is encountered in local x-ray phase-contrast tomography. Here we extend our previous theoretical framework from interior CT to interior differential phase-contrast tomography, and establish the solution uniqueness in this context. We employ the analytic continuation method and high order total variation minimization which we developed in our previous work for interior CT, and prove that an image in a region of interest (ROI) can be uniquely reconstructed from truncated high order differential projection data if the image is known a priori in a sub-region of the ROI or the image is piecewise polynomial in the ROI. Preliminary numerical experiments support the theoretical finding. PMID:23324783

Yang, Jiansheng; Cong, Wenxiang; Jiang, Ming; Wang, Ge

2013-01-01

473

High-order beam optics: An overview  

SciTech Connect

Beam-transport codes have been around for as long as thirty years and high-order codes, second-order at least, for close to twenty years. Before this period of design-code development, there was considerable high-order treatment, but it was almost entirely analytical. History has a way of repeating itself, and the current excitement in the field of high-order optics is based on the application of Lie algebra and the so-called differential algebra to beam-transport codes, both of which are highly analytical in foundation. Some of the main design tools available today will be described, giving a little of their history, and will conclude by trying to convey some of the excitement in the field through a brief description of Lie and differential algebra. 30 refs., 7 figs.

Heighway, E.A.

1988-01-01

474

The structure of rotating polytropes (Second order)  

NASA Astrophysics Data System (ADS)

The structural equations for the inner and outer regions of a rotating polytrope (as used in stellar-structure models) are reformulated to include second-order terms in the perturbation parameter alpha and solved by extending the method of Monaghan and Roxburgh (1965), as used in the first order by Singh and Singh (1982). A critical configuration at which the centrifugal force balances gravity at the equator is defined, and numerical results for parameter values of interest in astrophysics are presented in tables. Comparison of the results for alpha, xi(e), and xi(p) with those of James (1964) and Singh and Singh (1982) shows that the improvement introduced by the use of the second-order method is small, and continued modeling based on the first-order values is recommended.

Singh, G. R.; Singh, M.

1984-11-01

475

25 CFR 213.29 - Division orders.  

Code of Federal Regulations, 2013 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF RESTRICTED LANDS OF MEMBERS OF FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING Rents and Royalties § 213.29 Division orders. (a) Lessees may...

2013-04-01

476

25 CFR 213.29 - Division orders.  

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF RESTRICTED LANDS OF MEMBERS OF FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING Rents and Royalties § 213.29 Division orders. (a) Lessees may...

2014-04-01

477

25 CFR 213.29 - Division orders.  

Code of Federal Regulations, 2010 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF RESTRICTED LANDS OF MEMBERS OF FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING Rents and Royalties § 213.29 Division orders. (a) Lessees may...

2010-04-01

478

25 CFR 213.29 - Division orders.  

Code of Federal Regulations, 2011 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF RESTRICTED LANDS OF MEMBERS OF FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING Rents and Royalties § 213.29 Division orders. (a) Lessees may...

2011-04-01

479

25 CFR 213.29 - Division orders.  

Code of Federal Regulations, 2012 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF RESTRICTED LANDS OF MEMBERS OF FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING Rents and Royalties § 213.29 Division orders. (a) Lessees may...

2012-04-01

480

49 CFR 190.219 - Consent order.  

Code of Federal Regulations, 2010 CFR

...Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED...steps and of all right to seek judicial review or otherwise challenge or contest the validity of that order; (3) An...

2010-10-01

481

High order accurate solutions of viscous problems  

NASA Technical Reports Server (NTRS)

We consider a fourth order extension to MacCormack's scheme. The original extension was fourth order only for the inviscid terms but was second order for the viscous terms. We show how to modify the viscous terms so that the scheme is uniformly fourth order in the spatial derivatives. Applications are given to some boundary layer flows. In addition, for applications to shear flows the effect of the outflow boundary conditions are very important. We compare the accuracy of several of these different boundary conditions for both boundary layer and shear flows. Stretching at the outflow usually increases the oscillations in the numerical solution but the addition of a filtered sponge layer (with or without stretching) reduces such oscillations. The oscillations are generated by insufficient resolution of the shear layer. When the shear layer is sufficiently resolved then oscillations are not generated and there is less of a need for a nonreflecting boundary condition.

Hayder, M. Ehtesham; Turkel, Eli

1993-01-01

482

76 FR 766 - Amtrak Emergency Routing Orders  

Federal Register 2010, 2011, 2012, 2013

...application of the National Railroad Passenger Corporation (Amtrak...owned and operated by freight railroads, which are subject to the...closed as the result of a derailment, unscheduled maintenance...to issue orders requiring railroads to make their facilities...

2011-01-06

483

30 CFR 843.11 - Cessation orders.  

Code of Federal Regulations, 2010 CFR

...exploration or surface coal mining and reclamation operations...description of the portion of the coal exploration or surface coal mining and reclamation operation to...The order shall remain in effect until the condition,...

2010-07-01

484

30 CFR 843.11 - Cessation orders.  

Code of Federal Regulations, 2011 CFR

...exploration or surface coal mining and reclamation operations...description of the portion of the coal exploration or surface coal mining and reclamation operation to...The order shall remain in effect until the condition,...

2011-07-01

485

45 CFR 672.10 - Default order.  

Code of Federal Regulations, 2012 CFR

...Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ENFORCEMENT AND HEARING PROCEDURES § 672.10...showing the grounds for the order, conclusions regarding all material issues of law or discretion, and the penalty which is...

2012-10-01

486

45 CFR 672.10 - Default order.  

Code of Federal Regulations, 2011 CFR

...Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ENFORCEMENT AND HEARING PROCEDURES § 672.10...showing the grounds for the order, conclusions regarding all material issues of law or discretion, and the penalty which is...

2011-10-01

487

45 CFR 672.10 - Default order.  

...Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ENFORCEMENT AND HEARING PROCEDURES § 672.10...showing the grounds for the order, conclusions regarding all material issues of law or discretion, and the penalty which is...

2014-10-01

488

45 CFR 672.10 - Default order.  

Code of Federal Regulations, 2013 CFR

...Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ENFORCEMENT AND HEARING PROCEDURES § 672.10...showing the grounds for the order, conclusions regarding all material issues of law or discretion, and the penalty which is...

2013-10-01

489

78 FR 58995 - Order Denying Export Privileges  

Federal Register 2010, 2011, 2012, 2013

...Denying Export Privileges In the Matter of: Iman Kazerani, 153 Orient Way, Rutherford...District Court, District of New Jersey, Iman Kazerani (``Kazerani'') was convicted...hereby Ordered I. Until January 30, 2018, Iman Kazerani, with a last known address...

2013-09-25

490

49 CFR 190.239 - Safety orders.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Safety orders. 190.239 Section 190... PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY PIPELINE SAFETY PROGRAMS AND...

2010-10-01

491

High order Lagrangian velocity statistics in turbulence.  

PubMed

We report measurements of the Lagrangian velocity structure functions of orders 1 through 10 in a high Reynolds number (Taylor microscale Reynolds numbers of up to R(lambda) = 815 ) turbulence experiment. Passive tracer particles are tracked optically in three dimensions and in time, and velocities are calculated from the particle tracks. The structure function anomalous scaling exponents are measured both directly and using extended self-similarity and are found to be more intermittent than their Eulerian counterparts. Classical Kolmogorov inertial range scaling is also found for all structure function orders at times that trend downward as the order increases. The temporal shift of this classical scaling behavior is observed to saturate as the structure function order increases at times shorter than the Kolmogorov time scale. PMID:16486587

Xu, Haitao; Bourgoin, Mickaël; Ouellette, Nicholas T; Bodenschatz, Eberhard

2006-01-20

492

50 CFR 300.97 - Inseason orders.  

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2014-10-01

493

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2013 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2013-10-01

494

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2011 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2011-10-01

495

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2012 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2012-10-01

496

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2010 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2010-10-01

497

36 CFR 261.50 - Orders.  

Code of Federal Regulations, 2013 CFR

...Orders. (a) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake Tahoe...thereof. (b) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake...

2013-07-01

498

36 CFR 261.50 - Orders.  

Code of Federal Regulations, 2012 CFR

...Orders. (a) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake Tahoe...thereof. (b) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake...

2012-07-01

499

36 CFR 261.50 - Orders.  

Code of Federal Regulations, 2011 CFR

...Orders. (a) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake Tahoe...thereof. (b) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake...

2011-07-01

500

36 CFR 261.50 - Orders.  

Code of Federal Regulations, 2010 CFR

...Orders. (a) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake Tahoe...thereof. (b) The Chief, each Regional Forester, each Experiment Station Director, the Administrator of the Lake...

2010-07-01