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Sample records for generalised magnetic susceptibility

  1. Generalised relativistic Ohm's laws, extended gauge transformations, and magnetic linking

    SciTech Connect

    Pegoraro, F.

    2015-11-15

    Generalisations of the relativistic ideal Ohm's law are presented that include specific dynamical features of the current carrying particles in a plasma. Cases of interest for space and laboratory plasmas are identified where these generalisations allow for the definition of generalised electromagnetic fields that transform under a Lorentz boost in the same way as the real electromagnetic fields and that obey the same set of homogeneous Maxwell's equations.

  2. Magnetic susceptibilities of minerals

    USGS Publications Warehouse

    Rosenblum, Sam; Brownfield, I.K.

    2000-01-01

    Magnetic separation of minerals is a topic that is seldom reported in the literature for two reasons. First, separation data generally are byproducts of other projects; and second, this study requires a large amount of patience and is unusually tedious. Indeed, we suspect that most minerals probably are never investigated for this property. These data are timesaving for mineralogists who concentrate mono-mineralic fractions for chemical analysis, age dating, and for other purposes. The data can certainly be used in the ore-beneficiation industries. In some instances, magnetic-susceptibility data may help in mineral identification, where other information is insufficient. In past studies of magnetic separation of minerals, (Gaudin and Spedden, 1943; Tille and Kirkpatrick, 1956; Rosenblum, 1958; Rubinstein and others, 1958; Flinter, 1959; Hess, 1959; Baker, 1962; Meric and Peyre, 1963; Rojas and others, 1965; and Duchesne, 1966), the emphasis has been on the ferromagnetic and paramagnetic ranges of extraction. For readers interested in the history of magnetic separation of minerals, Krumbein and Pettijohn (1938, p. 344-346) indicated nine references back to 1848. The primary purpose of this paper is to report the magnetic-susceptibility data on as many minerals as possible, similar to tables of hardness, specific gravity, refractive indices, and other basic physical properties of minerals. A secondary purpose is to demonstrate that the total and best extraction ranges are influenced by the chemistry of the minerals. The following notes are offered to help avoid problems in separating a desired mineral concentrate from mixtures of mineral grains.

  3. Magnetic susceptibility, petrofabrics and strain

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham John

    1988-12-01

    Magnetic susceptibility is a non-destructive technique for quantifying the average fabric of a small sample of rock. The interpretation of the magnetic fabric is not always straightforward. However, the principal directions of the magnitude ellipsoid of susceptibility commonly show orientations consistent with the kinematic interpretations of folds, shear zones and other structural features. The directions may correspond with the orientations of strained objects or with the planar-linear mineral orientations. There will usually be multiple mineralogical sources of susceptibility, often involving silicates. If the sources are known, or if the susceptibility can be attributed to a single mineral species, it may be possible to establish a correlation between the strain ellipsoid and the susceptibility ellipsoid. This correlation will be of principal directions in many instances and occasionally there may be a weak correlation of strain magnitudes as well. In other circumstances it may be possible to establish a correlation between changes in susceptibility and the strain. Nevertheless magnetic fabric studies are not routine substitutes for strain analysis. Even where information on strain is not provided, the magnetic fabrics (and subfabrics) yield a measure of the preferred crystallographic orientation or preferred dimensional orientation of the minerals that may be integrated profitably with other petrofabric data. Experimental deformation of certain synthetic aggregates indicates that directions of magnetic susceptibility spin rapidly with advancing strain, especially where the matrix grains undergo crystal-plastic deformation. In certain experiments, simple shear appears to change the intensity of magnetic fabric more effectively than pure shear. Experiments indicate also that the initial anisotropy of a rock-like material is not easily overprinted by deformation whereas field studies are equivocal.

  4. Magnetic susceptibility of topological nodal semimetals

    NASA Astrophysics Data System (ADS)

    Mikitik, G. P.; Sharlai, Yu. V.

    2016-11-01

    Magnetic susceptibility of the topological Weyl, type-II Weyl, Dirac, and line node semimetals is theoretically investigated. Dependences of this susceptibility on the chemical potential, temperature, direction, and magnitude of the magnetic field are found. The obtained results show that magnetic measurements can be very useful in investigating these semimetals. As an example, we calculate magnetic susceptibility of Cd3As2 ,Na3Bi , and Ca3P2 .

  5. Magnetization and magnetic susceptibility of DyH3

    NASA Technical Reports Server (NTRS)

    Flood, D. J.

    1975-01-01

    The magnetization and differential magnetic susceptibility of powdered DyH3 samples are measured at a temperature of 4.2 K in applied magnetic fields ranging up to 9 Teslas. The differential magnetic susceptibility is also investigated in the zero applied field. Magnetization is plotted as a function of field strength, and differential susceptibility is described as a function of both field strength and temperature. A saturation magnetic moment of 5.12 Bohr magnetons per ion is derived from the magnetization data, and the zero-field susceptibility measurements are found to indicate antiferromagnetic ordering below 3.45 K. The susceptibility at 4.2 K is shown to have an inverse-square dependence on field strength for values of not less than 0.3 Tesla.

  6. Magnetic susceptibility of tetragonal titanium dioxide

    USGS Publications Warehouse

    Senftle, F.E.; Pankey, T.; Grant, F.A.

    1960-01-01

    Careful measurements have been made of the magnetic susceptibility of the rutile and anatase crystalline forms of titanium dioxide. The magnetic susceptibility of a single crystal of high-purity rutile was found to be (0.067??0.0015)??10-6 emu per gram, and was temperature-independent from 55??to 372??K. Difficulty was encountered in obtaining a good value of the magnetic susceptibility of anatase because of impurities. However, a value of 0.02??10-6 emu per gram was obtained as a maximum value for anatase powder. A discussion is given for the different values obtained for anatase and rutile. ?? 1960 The American Physical Society.

  7. Magnetization and magnetic susceptibility of DyH3

    NASA Technical Reports Server (NTRS)

    Flood, D. J.

    1974-01-01

    The magnetization and differential magnetic susceptibility of powdered samples of DyH3 have been measured at 4.2 K in applied magnetic fields ranging to 9 Teslas. The differential magnetic susceptibility has also been studied in zero applied field as a function of temperature. The magnetization data are described by an equation of the form M = aB/(1 + bB + cB. The ratio a/b is a measure of the saturation magnetization and gives an effective moment of 5.12 Bohr magnetons per ion. The zero field susceptibility exhibits a maximum at T = 3.45 K, and an inflection point near 2.85 K. The susceptibility at 4.2 K has a 1/B squared dependence on the applied magnetic field for B approximately greater than 0.3 Teslas.

  8. Materials with low DC magnetic susceptibility for sensitive magnetic measurements

    NASA Astrophysics Data System (ADS)

    Khatiwada, R.; Dennis, L.; Kendrick, R.; Khosravi, M.; Peters, M.; Smith, E.; Snow, W. M.

    2016-02-01

    Materials with very low DC magnetic susceptibility have many scientific applications. To our knowledge however, relatively little research has been conducted with the goal to produce a totally nonmagnetic material. This phrase in our case means after spatially averaging over macroscopic volumes, it possesses an average zero DC magnetic susceptibility. We report measurements of the DC magnetic susceptibility of three different types of nonmagnetic materials at room temperature: (I) solutions of paramagnetic salts and diamagnetic liquids, (II) liquid gallium-indium alloys and (III) pressed powder mixtures of tungsten and bismuth. The lowest measured magnetic susceptibility among these candidate materials is in the order of 10-9 cgs volume susceptibility units, about two orders of magnitude smaller than distilled water. In all cases, the measured concentration dependence of the magnetic susceptibility is consistent with that expected for the weighted sum of the susceptibilities of the separate components within experimental error. These results verify the well-known Wiedemann additivity law for the magnetic susceptibility of inert mixtures of materials and thereby realize the ability to produce materials with small but tunable magnetic susceptibility. For our particular scientific application, we are also looking for materials with the largest possible number of neutrons and protons per unit volume. The gallium-indium alloys fabricated and measured in this work possess to our knowledge the smallest ratio of volume magnetic susceptibility to nucleon number density per unit volume for a room temperature liquid, and the tungsten-bismuth pressed powder mixtures possess to our knowledge the smallest ratio of volume magnetic susceptibility to nucleon number density per unit volume for a room temperature solid. This ratio is a figure of merit for a certain class of precision experiments that search for possible exotic spin-dependent forces of Nature.

  9. Absolute method of measuring magnetic susceptibility

    USGS Publications Warehouse

    Thorpe, A.; Senftle, F.E.

    1959-01-01

    An absolute method of standardization and measurement of the magnetic susceptibility of small samples is presented which can be applied to most techniques based on the Faraday method. The fact that the susceptibility is a function of the area under the curve of sample displacement versus distance of the magnet from the sample, offers a simple method of measuring the susceptibility without recourse to a standard sample. Typical results on a few substances are compared with reported values, and an error of less than 2% can be achieved. ?? 1959 The American Institute of Physics.

  10. Sources of magnetic susceptibility in a slate

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham; Mothersill, John; Tarling, Don; Alford, Craig

    1986-01-01

    Magnetic susceptibility and its anisotropy in the Borrowdale Volcanic slates at Kentmere in the English Lake District are attributed largely to preferred orientation of a paramagnetic chlorite of diabantite-ripidolite composition. In units of 10 -6 cgs/g, the principal susceptibilities for the slates are 9.61; 9.42; 8.69 and for the chlorite grains the minimum anisotropy is represented by principal susceptibilities of 11.57; 11.22 and 9.15. Because the magnetic susceptibility is carried by a tightly packed, matrix-forming mineral that has recrystallised during the deformation it is not possible to imagine simple grain rotation as being responsible for the anisotropy of susceptibility.

  11. Magnetic Susceptibility of Collapsed Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Ando, Tsuneya

    2017-02-01

    The orbital magnetic susceptibility is calculated in collapsed carbon nanotubes within an effective-mass scheme for two magnetic-field configurations, perpendicular and parallel to the flattened plane. The response is diamagnetic in both directions and is much larger for the perpendicular configuration, with some rare exceptions. In chiral nanotubes, calculated results show small and almost negligible effects of collapsing except for some modification due to change in the effective magnetic field. In nonchiral zigzag and armchair nanotubes, the susceptibility is strongly modified, depending on relative displacement of two layers in the flattened region.

  12. Magnetic Susceptibility of Wet vs. Dry Sediment and Mass Normalized vs. Volume Normalized Magnetic Susceptibility

    NASA Astrophysics Data System (ADS)

    Kletetschka, G.; Hruba, J.; Nabelek, L.

    2015-12-01

    The measurement of magnetic susceptibility in sediments represents a fast and non-destructive technique that can be used to deduce the concentration of magnetic minerals [1, 2]. Magnetic minerals change their magnetic properties with temperature [3]. Heating (during a fire, laboratory, with the purpose of manufacturing a product, etc.) can modify a number of sediment properties [4, 5]. Heat-induced sediment mineralogical changes may cause irreversible changes in the sediment mineral structure and composition, and they occur at a wide range of temperature [6]. We provided measurements of magnetic susceptibility on samples from the Stara Jimka (SJ) paleo lacustrine site in the Bohemian Forest using magnetic susceptibility meter MS-30. Sediment samples of approximately 0.2 cm thickness were weighed and put into plastic containers. First, measurements of magnetic susceptibility were taken on wet samples. Then the containers were put into the oven and sediment was dried at temperature of 110°C. After drying and cooling to room temperature, measurements of magnetic susceptibility were repeated. Dry samples were also weighed. Comparison of magnetic susceptibility of dry versus wet samples showed higher values of magnetic susceptibility of dry samples. This enhancement was probably caused during oven-drying, when constituents of sediment (mainly clays) underwent heat-induced changes. We also compared volume normalized values of magnetic susceptibility with mass normalized values. Mass normalized magnetic susceptibility was burdened by greater noise. References: [1] QUIJANO, L. et al. 2001. Magnetic Susceptibilty in Topsoils and Bulk Cores of Cultivated Calcisols. [2] DEARING, J. A. 1994. Environmental Magnetic Susceptibility. [3] HANESCH, M. and SCHOLGER, R. 2005. The Influence of Soil Type on the Magnetic Susceptibility Measured throughout Soil Profiles. [4] FARWIG, V. J. et al. 2004. The Effects of Heating on Mineral Magnetic Enhancement of Soils. [5] KLETETSCHKA, G

  13. Magnetic susceptibility of petroleum reservoir fluids

    NASA Astrophysics Data System (ADS)

    Ivakhnenko, Oleksandr P.; Potter, David K.

    A knowledge of the magnetic properties of petroleum reservoir fluids may provide new techniques for improved reservoir characterisation, petroleum exploration and production. However, magnetic information is currently scarce for the vast majority of reservoir fluids. For instance, there is little in the literature concerning basic magnetic susceptibility values of crude oils or formation waters. We have therefore measured the mass magnetic susceptibility ( χm) of several crude oils, refined oil fractions, and formation waters from local and world-wide sites. All the fluids measured were diamagnetic, however there were distinct differences in magnitude between the different fluid types. In particular, χm for the crude oils was more negative than for the formation waters of the same locality. The magnetic susceptibility of the oils appears to be related to their main physical and chemical properties. The results correlated with the density, residue content, API (American Petroleum Institute) gravity, viscosity, sulphur content and metal concentration of the fluids. Light fractions of crude oil were the most diamagnetic. The magnetic measurements potentially allow physical and chemical differences between the fluids to be rapidly characterised. The results suggest other possible applications, such as passive in situ magnetic susceptibility sensors for fluid monitoring (for example, the onset of water breakthrough, or the detection of migrating fines) in reservoirs, which would provide an environmentally friendly alternative to radioactive tracers. The mass magnetic susceptibilities of the fluids in relation to typical reservoir minerals may also play a role in fluid-rock interactions, such as studies of wettability. The χm of crude oil from the various world-wide oil provinces that were tested also showed some differences, possibly reflecting broad physical and chemical features of the geological history of each province.

  14. Separation of magnetic susceptibility components from magnetization curves

    NASA Astrophysics Data System (ADS)

    Kosareva, L.; Nourgaliev, D.; Kuzina, D.; Spassov, S.; Fattakhov, A.

    2014-12-01

    Modern lake sediments are a unique source of information for climate changes, regionally and globally, because all environmental variations are recorded by these sediments with high resolution. The magnetic properties of Chernyshov Bay (Aral Sea) sediments we investigated from core number 4 (N45o57'04.2''; E59o17'14.3'') are taken at far water depth of 9.5 m. The length of the core is 4.16 m. Samples for measurements were taken to plastic sample boxes with internal dimensions 2x2x2 cm. Remanent magnetization curves were measured by coercivity spectrometer for the separate determination of the different contributions to the total bulk magnetic susceptibility. There was measured also magnetic susceptibility using MS2 susceptibility meter. Those operations were done for data comparison between 2 susceptibilities obtained from different equipment. Our goal is to decipher the magnetic susceptibility signal in lake sediments by decomposing the bulk susceptibility signal of a lake sediment sequence into ferromagnetic (χf), dia-/paramagnetic (χp) and superparamagnetic (χsp) components using data from remanent and indused magnetization curves Each of these component has a different origin: paramagnetic minerals are usually attributed to terrigenous sediment input, ferromagnetics are of biogenic origin, and superparamagnetic minerals may be of either biogenic or terrigenous origin. Comparison between susceptibility measurements of MS2-Bartington susceptometer and of the coercivity spectrometer has shown good correlation. The susceptibility values measured in two different equipment are fairly close and indicate thus the reliability the proposed method. In research also has shown water level changes in Aral Sea based on magnetic susceptibility. The work is performed according to the Russian Government Program of Competitive Growth of Kazan Federal University also by RFBR research projects No. 14-05-31376 - а, 14-05-00785- а.

  15. Anisotropy of the magnetic susceptibility of gallium

    USGS Publications Warehouse

    Pankey, T.

    1960-01-01

    The bulk magnetic susceptibilities of single gallium crystals and polycrystalline gallium spheres were measured at 25??C. The following anisotropic diamagnetic susceptibilities were found: a axis (-0.119??0. 001)??10-6 emu/g, b axis (-0.416??0.002)??10 -6 emu/g, and c axis (-0.229??0.001) emu/g. The susceptibility of the polycrystalline spheres, assumed to be the average value for the bulk susceptibility of gallium, was (-0.257??0.003)??10-6 emu/g at 25??C, and (-0.299??0.003)??10-6 emu/g at -196??C. The susceptibility of liquid gallium was (0.0031??0.001) ??10-6 emu/g at 30??C and 100??C. Rotational diagrams of the susceptibilities in the three orthogonal planes of the unit cell were not sinusoidal. The anisotropy in the single crystals was presumably caused by the partial overlap of Brillouin zone boundaries by the Fermi-energy surface. The large change in susceptibility associated with the change in state was attributed to the absence of effective mass influence in the liquid state. ?? 1960 The American Institute of Physics.

  16. Magnetic Susceptibility in the Vertebral Column

    NASA Astrophysics Data System (ADS)

    Schick, F.; Nagele, T.; Lutz, O.; Pfeffer, K.; Giehl, J.

    1994-01-01

    A magnetic resonance method is described which provides good-quality field-mapping images of the spine, although the in vivo signals from red bone marrow of the vertebral bodies exhibit similar fractions of lipid and water protons with their chemical-shift difference of 3.4 ppm. The susceptibilities of bone marrow and intervertebral disks were examined in 20 cadaveric human spines, 9 healthy volunteers, and 9 patients with degenerative disk alterations. The influence of geometrical properties was studied in cylindrical spine phantoms of different size and contents with different susceptibility. The measurements reveal interindividual differences of the susceptibility of the intervertebral disks in healthy subjects. Three out of nine degenerated disks with low signal in T2-weighted spin-echo images showed irregularities of the field distribution within the nucleus pulposus.

  17. Magnetic susceptibility as a biosignature in stromatolites

    NASA Astrophysics Data System (ADS)

    Petryshyn, Victoria A.; Corsetti, Frank A.; Frantz, Carie M.; Lund, Steve P.; Berelson, William M.

    2016-03-01

    Microbialites have long been a focus of study in geobiology because they are macroscopic sedimentary records of the activities of microscopic organisms. However, abiotic processes can result in microbialite-like morphologies. Developing robust tools for substantiating the biogenicity of putative microbialites remains an important challenge. Here, we report a new potential biosignature based on the detrital magnetic mineral component present in nearly all sedimentary rocks. Detrital grains falling onto a hard, abiogenic, chemically precipitated structure would be expected to roll off surfaces at high incline angles. Thus, the distribution of grains in an abiogenic microbialite should exhibit a dependence on the dip angle along laminae. In contrast, a microbialite formed by the active trapping and binding of detrital grains by microorganisms could exhibit a distribution of detrital grains significantly less dependent on the dip angle of the laminae. However, given that most ancient stromatolites are micritic (composed of carbonate mud), tracking detrital grains vs. precipitated carbonate is not straightforward. Recent advances in our ability to measure miniscule magnetic fields open up the possibility to map magnetic susceptibility as a tracer of detrital grains in stromatolites. In abiogenic carbonate precipitation experiments, magnetic susceptibility fell to zero when the growth surface was inclined above 30° (the angle at which grains rolled off). In cyanobacterial mat experiments, even vertically inclined mats held magnetic material. The results indicate that cyanobacterial mats trap and bind small grains more readily than abiogenic carbonate precipitates alone. A variety of stromatolites of known and unknown biogenicity were then analyzed. Tested stromatolites span many different ages (Eocene to Holocene) and depositional environments (hot springs, lakes), and compositional forms (micritic, sparry crusts, etc.). The results were consistent with the laboratory

  18. Nonlinear Susceptibility Magnitude Imaging of Magnetic Nanoparticles.

    PubMed

    Ficko, Bradley W; Giacometti, Paolo; Diamond, Solomon G

    2015-03-15

    This study demonstrates a method for improving the resolution of susceptibility magnitude imaging (SMI) using spatial information that arises from the nonlinear magnetization characteristics of magnetic nanoparticles (mNPs). In this proof-of-concept study of nonlinear SMI, a pair of drive coils and several permanent magnets generate applied magnetic fields and a coil is used as a magnetic field sensor. Sinusoidal alternating current (AC) in the drive coils results in linear mNP magnetization responses at primary frequencies, and nonlinear responses at harmonic frequencies and intermodulation frequencies. The spatial information content of the nonlinear responses is evaluated by reconstructing tomographic images with sequentially increasing voxel counts using the combined linear and nonlinear data. Using the linear data alone it is not possible to accurately reconstruct more than 2 voxels with a pair of drive coils and a single sensor. However, nonlinear SMI is found to accurately reconstruct 12 voxels (R(2) = 0.99, CNR = 84.9) using the same physical configuration. Several time-multiplexing methods are then explored to determine if additional spatial information can be obtained by varying the amplitude, phase and frequency of the applied magnetic fields from the two drive coils. Asynchronous phase modulation, amplitude modulation, intermodulation phase modulation, and frequency modulation all resulted in accurate reconstruction of 6 voxels (R(2) > 0.9) indicating that time multiplexing is a valid approach to further increase the resolution of nonlinear SMI. The spatial information content of nonlinear mNP responses and the potential for resolution enhancement with time multiplexing demonstrate the concept and advantages of nonlinear SMI.

  19. Magnetic Susceptibility Measurement System for Small and Weak Magnetic Substances

    NASA Astrophysics Data System (ADS)

    Grant, Julius Reynard

    In this study a system is constructed which uses a force method for taking magnetic susceptibility measurements of small (< 100 mg) and weak (< 100x 10-6 emu/g) magnetic substances. The system is constructed with several pieces of readily available hardware. Some of the hardware includes a stable frame structure, a CAHN electrobalance, electromagnet, a thermocouple, a power supply, interfaces, and a personal computer. Each of these components is tested individually as well as together with other devices. Since the electrobalance is extremely sensitive the balance must be placed on a stable frame. The completed system is capable of studying the magnetic properties from room temperature to 77 K of a variety of samples. In addition, a novel method is developed to produce hysteresis loops for especially small and weak magnetic samples. Extensive testing is done to ensure the magnetization results obtained on known samples compare with what has been reported. Some of the samples that have been measured are MnO (TN was 122 K), CdSe (magnetic susceptibility was -0.3 x 10-6 emu/g) with iron attached ligands, FexTeyOz type samples with and without nickel, a YBaCuO superconductor, and cells doped with magnetite nanoparticles. The results are compared to measurements made with SQUID magnetometers.

  20. Structural and magnetic properties of multi-core nanoparticles analysed using a generalised numerical inversion method

    PubMed Central

    Bender, P.; Bogart, L. K.; Posth, O.; Szczerba, W.; Rogers, S. E.; Castro, A.; Nilsson, L.; Zeng, L. J.; Sugunan, A.; Sommertune, J.; Fornara, A.; González-Alonso, D.; Barquín, L. Fernández; Johansson, C.

    2017-01-01

    The structural and magnetic properties of magnetic multi-core particles were determined by numerical inversion of small angle scattering and isothermal magnetisation data. The investigated particles consist of iron oxide nanoparticle cores (9 nm) embedded in poly(styrene) spheres (160 nm). A thorough physical characterisation of the particles included transmission electron microscopy, X-ray diffraction and asymmetrical flow field-flow fractionation. Their structure was ultimately disclosed by an indirect Fourier transform of static light scattering, small angle X-ray scattering and small angle neutron scattering data of the colloidal dispersion. The extracted pair distance distribution functions clearly indicated that the cores were mostly accumulated in the outer surface layers of the poly(styrene) spheres. To investigate the magnetic properties, the isothermal magnetisation curves of the multi-core particles (immobilised and dispersed in water) were analysed. The study stands out by applying the same numerical approach to extract the apparent moment distributions of the particles as for the indirect Fourier transform. It could be shown that the main peak of the apparent moment distributions correlated to the expected intrinsic moment distribution of the cores. Additional peaks were observed which signaled deviations of the isothermal magnetisation behavior from the non-interacting case, indicating weak dipolar interactions.

  1. Magnetic Susceptibility Measurements for in Situ Characterization of Lunar Soil

    NASA Technical Reports Server (NTRS)

    Oder, R. R.

    1992-01-01

    Magnetic separation is a viable method for concentration of components of lunar soils and rocks for use as feedstocks for manufacture of metals, oxygen, and for recovery of volatiles such as He-3. Work with lunar materials indicates that immature soils are the best candidates for magnetic beneficiation. The magnetic susceptibility at which selected soil components such as anorthite, ilmenite, or metallic iron are separated is not affected by soil maturity, but the recovery of the concentrated components is. Increasing soil maturity lowers recovery. Mature soils contain significant amounts of glass-encased metallic iron. Magnetic susceptibility, which is sensitive to metallic iron content, can be used to measure soil maturity. The relationship between the ratio of magnetic susceptibility and iron oxide and the conventional maturity parameter, I(sub s)/FeO, ferromagnetic resonant intensity divided by iron oxide content is given. The magnetic susceptibilities were determined using apparatus designed for magnetic separation of the lunar soils.

  2. MR Measurement of Alloy Magnetic Susceptibility: Towards Developing Tissue-Susceptibility Matched Metals

    PubMed Central

    Astary, Garrett W.; Peprah, Marcus K.; Fisher, Charles R.; Stewart, Rachel L.; Carney, Paul R.; Sarntinoranont, Malisa; Meisel, Mark W.; Manuel, Michele V.; Mareci, Thomas H.

    2013-01-01

    Magnetic resonance imaging (MRI) can be used to relate structure to function mapped with high-temporal resolution electrophysiological recordings using metal electrodes. Additionally, MRI may be used to guide the placement of electrodes or conductive cannula in the brain. However, the magnetic susceptibility mismatch between implanted metals and surrounding brain tissue can severely distort MR images and spectra, particularly in high magnetic fields. In this study, we present a modified MR method of characterizing the magnetic susceptibility of materials that can be used to develop biocompatible, metal alloys that match the susceptibility of host tissue in order to eliminate MR distortions proximal to the implant. This method was applied at 4.7 T and 11.1 T to measure the susceptibility of a model solid-solution alloy of Cu and Sn, which is inexpensive but not biocompatible. MR-derived relative susceptibility values of four different compositions of Cu-Sn alloy deviated by less than 3.1% from SQUID magnetometry absolute susceptibility measurements performed up to 7 T. These results demonstrate that the magnetic susceptibility varies linearly with atomic percentage in these solid-solution alloys, but are not simply the weighted average of Cu and Sn magnetic susceptibilities. Therefore susceptibility measurements are necessary when developing susceptibility-matched, solid-solution alloys for the elimination of susceptibility artifacts in MR. This MR method does not require any specialized equipment and is free of geometrical constraints, such as sample shape requirements associated with SQUID magnetometry, so the method can be used at all stages of fabrication to guide the development of a susceptibility matched, biocompatible device. PMID:23727587

  3. MR measurement of alloy magnetic susceptibility: towards developing tissue-susceptibility matched metals.

    PubMed

    Astary, Garrett W; Peprah, Marcus K; Fisher, Charles R; Stewart, Rachel L; Carney, Paul R; Sarntinoranont, Malisa; Meisel, Mark W; Manuel, Michele V; Mareci, Thomas H

    2013-08-01

    Magnetic resonance imaging (MRI) can be used to relate structure to function mapped with high-temporal resolution electrophysiological recordings using metal electrodes. Additionally, MRI may be used to guide the placement of electrodes or conductive cannula in the brain. However, the magnetic susceptibility mismatch between implanted metals and surrounding brain tissue can severely distort MR images and spectra, particularly in high magnetic fields. In this study, we present a modified MR method of characterizing the magnetic susceptibility of materials that can be used to develop biocompatible, metal alloys that match the susceptibility of host tissue in order to eliminate MR distortions proximal to the implant. This method was applied at 4.7T and 11.1T to measure the susceptibility of a model solid-solution alloy of Cu and Sn, which is inexpensive but not biocompatible. MR-derived relative susceptibility values of four different compositions of Cu-Sn alloy deviated by less than 3.1% from SQUID magnetometry absolute susceptibility measurements performed up to 7T. These results demonstrate that the magnetic susceptibility varies linearly with atomic percentage in these solid-solution alloys, but are not simply the weighted average of Cu and Sn magnetic susceptibilities. Therefore susceptibility measurements are necessary when developing susceptibility-matched, solid-solution alloys for the elimination of susceptibility artifacts in MR. This MR method does not require any specialized equipment and is free of geometrical constraints, such as sample shape requirements associated with SQUID magnetometry, so the method can be used at all stages of fabrication to guide the development of a susceptibility matched, biocompatible device.

  4. The influence of soil moisture on magnetic susceptibility measurements

    NASA Astrophysics Data System (ADS)

    Maier, G.; Scholger, R.; Schön, J.

    2006-06-01

    An important methodological question for magnetic susceptibility measurements is if a variation of the soil conductivity, as a result of a change in soil moisture, influences the measured susceptibility values. An answer to this question is essential because an accurate magnetic susceptibility mapping requires a grid of comparable magnetic susceptibility values, which indicate the magnetic iron-mineral contents of the soils. Therefore, in the framework of the MAGPROX project (EU-Project EVK2-CT-1999-00019), the study aims at investigating the influence of soil moisture and the possible correlation between magnetic susceptibility and electric conductivity. This approach was realised by model experiments in the laboratory and a field monitoring experiment, which was performed in an analogical manner as the model. For the laboratory experiment, a plastic tub with a water in- and outflow system and installed lines of electrodes was used. The measurements were carried out with layers of different magnetic material within the experimental sand formation under varying water saturation conditions. For the field experiment, which was carried out from July to December 2003, two test sites were selected. The magnetic susceptibility was measured by means of the recently developed vertical soil profile kappa meter SM400 and a commonly used Bartington MS2D probe. The electric resistivity was recorded using a 4-point light system (laboratory) and a ground conductivity meter EM38 (field). The knowledge of the resistivity of the sand formation enabled an estimation of porosity and water saturation in consideration of the Archie equations. The laboratory experiment results showed a very slight variation of measured magnetic susceptibility under different degrees of moisture, indicating mainly the influence from the diamagnetic contribution of the water volume. A measurement error in connection with the measurement method, for example caused by an interfering effect of soil

  5. Dynamic magnetic susceptibility and electrical detection of ferromagnetic resonance

    NASA Astrophysics Data System (ADS)

    Zhang, Yin; Wang, X. S.; Yuan, H. Y.; Kang, S. S.; Zhang, H. W.; Wang, X. R.

    2017-03-01

    The dynamic magnetic susceptibility of magnetic materials near ferromagnetic resonance (FMR) is very important in interpreting the dc voltage obtained in its electrical detection. Based on the causality principle and the assumption that the usual microwave absorption lineshape of a homogeneous magnetic material around FMR is Lorentzian, the general forms of the dynamic magnetic susceptibility of an arbitrary sample and the corresponding dc voltage lineshapes of its electrical detection were obtained. Our main findings are as follows. (1) The dynamic magnetic susceptibility is not a Polder tensor for a material with an arbitrary magnetic anisotropy. The two off-diagonal matrix elements of the tensor near FMR are not, in general, opposite to each other. However, the linear response coefficient of the magnetization to the total radio frequency (rf) field (the sum of the external and internal rf fields due to precessing magnetization is a quantity which cannot be measured directly) is a Polder tensor. This may explain why the two off-diagonal susceptibility matrix elements were always wrongly assumed to be opposite to each other in almost all analyses. (2) The frequency dependence of dynamic magnetic susceptibility near FMR is fully characterized by six real numbers, while its field dependence is fully characterized by seven real numbers. (3) A recipe of how to determine these numbers by standard microwave absorption measurements for a sample with an arbitrary magnetic anisotropy is proposed. Our results allow one to unambiguously separate the contribution of the anisotropic magnetoresistance to the dc voltage signals from the anomalous Hall effect. With these results, one can reliably extract the information of spin pumping and the inverse spin-Hall effect, and determine the spin-Hall angle. (4) In the case that resonance frequency is not sensitive to the applied static magnetic field, the field dependence of the matrix elements of dynamic magnetic susceptibility, as

  6. Magnetic susceptibility anisotropy outside the central nervous system.

    PubMed

    Dibb, Russell; Xie, Luke; Wei, Hongjiang; Liu, Chunlei

    2017-04-01

    Magnetic-susceptibility-based MRI has made important contributions to the characterization of tissue microstructure, chemical composition, and organ function. This has motivated a number of studies to explore the link between microstructure and susceptibility in organs and tissues throughout the body, including the kidney, heart, and connective tissue. These organs and tissues have anisotropic magnetic susceptibility properties and cellular organizations that are distinct from the lipid organization of myelin in the brain. For instance, anisotropy is traced to the epithelial lipid orientation in the kidney, the myofilament proteins in the heart, and the collagen fibrils in the knee cartilage. The magnetic susceptibility properties of these and other tissues are quantified using specific MRI tools: susceptibility tensor imaging (STI), quantitative susceptibility mapping (QSM), and individual QSM measurements with respect to tubular and filament directions determined from diffusion tensor imaging. These techniques provide complementary and supplementary information to that produced by traditional MRI methods. In the kidney, STI can track tubules in all layers including the cortex, outer medulla, and inner medulla. In the heart, STI detected myofibers throughout the myocardium. QSM in the knee revealed three unique layers in articular cartilage by exploiting the anisotropic susceptibility features of collagen. While QSM and STI are promising tools to study tissue susceptibility, certain technical challenges must be overcome in order to realize routine clinical use. This paper reviews essential experimental findings of susceptibility anisotropy in the body, the underlying mechanisms, and the associated MRI methodologies. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Computed inverse MRI for magnetic susceptibility map reconstruction

    PubMed Central

    Chen, Zikuan; Calhoun, Vince

    2015-01-01

    Objective This paper reports on a computed inverse magnetic resonance imaging (CIMRI) model for reconstructing the magnetic susceptibility source from MRI data using a two-step computational approach. Methods The forward T2*-weighted MRI (T2*MRI) process is decomposed into two steps: 1) from magnetic susceptibility source to fieldmap establishment via magnetization in a main field, and 2) from fieldmap to MR image formation by intravoxel dephasing average. The proposed CIMRI model includes two inverse steps to reverse the T2*MRI procedure: fieldmap calculation from MR phase image and susceptibility source calculation from the fieldmap. The inverse step from fieldmap to susceptibility map is a 3D ill-posed deconvolution problem, which can be solved by three kinds of approaches: Tikhonov-regularized matrix inverse, inverse filtering with a truncated filter, and total variation (TV) iteration. By numerical simulation, we validate the CIMRI model by comparing the reconstructed susceptibility maps for a predefined susceptibility source. Results Numerical simulations of CIMRI show that the split Bregman TV iteration solver can reconstruct the susceptibility map from a MR phase image with high fidelity (spatial correlation≈0.99). The split Bregman TV iteration solver includes noise reduction, edge preservation, and image energy conservation. For applications to brain susceptibility reconstruction, it is important to calibrate the TV iteration program by selecting suitable values of the regularization parameter. Conclusions The proposed CIMRI model can reconstruct the magnetic susceptibility source of T2*MRI by two computational steps: calculating the fieldmap from the phase image and reconstructing the susceptibility map from the fieldmap. The crux of CIMRI lies in an ill-posed 3D deconvolution problem, which can be effectively solved by the split Bregman TV iteration algorithm. PMID:22446372

  8. Anisotropy of magnetic susceptibility: Measurement schemes

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham John; Stupavsky, Mike

    The precision of AMS determination is enhanced by measuring susceptibility in directions with a uniform orientation distribution that include the four body diagonals. Some standard 10.5 cm³ samples with mean susceptibility < 100µSI possess too few “magnetic” grains for reliable petrofabric interpretation whatever the measurement strategy. We should only interpret their AMS if they pass fabric homogeneity tests.

  9. Pyrolytic Graphite Foam: A Passive Magnetic Susceptibility Matching Material

    PubMed Central

    Lee, Gary C.; Goodwill, Patrick W.; Phuong, Kevin; Inglis, Ben A.; Scott, Greig C.; Hargreaves, Brian A.; Li, Lizabeth; Chen, Alex C.; Shah, Rachana N.; Conolly, Steven M.

    2012-01-01

    Purpose To evaluate a novel soft, lightweight cushion that can match the magnetic susceptibility of human tissue. The magnetic susceptibility difference between air and tissue produces field inhomogeneities in the B0 field, which leads to susceptibility artifacts in MR studies. Materials and Methods Pyrolytic graphite (PG) microparticles are uniformly embedded into a foam cushion to reduce or eliminate field inhomogeneities at accessible air and tissue interfaces. 3T MR images and field maps of an air/water/PG foam phantom were acquired. Q measurements on a 4T tuned head coil and pulse sequence heating tests at 3T were also performed. Results The PG foam improved susceptibility matching, reduced the field perturbations in phantoms, does not heat, and is non-conductive. Conclusion The susceptibility matched PG foam is lightweight, safe for patient use, adds no noise or MRI artifacts, is compatible with RF coil arrays, and improves B0 homogeneity, which enables more robust MR studies. PMID:20815067

  10. Relationship between magnetic susceptibility and strain in laboratory experiments

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham; Alford, Craig

    1987-02-01

    Under experimental conditions of 1.5 kbar confining pressure and at a strain-rate of 5 × 10 -6 sec -1 at room temperature the principal directions of magnetic susceptibility of a dry, synthetic, magnetite-bearing sandstone rotate toward principal strain directions. The rotation is faster than that expected from rotation of a line in homogeneous strain. Fluid pressures of 200 or 700 bars do not appear to affect the development of anisotropy of susceptibility. The change in bulk anisotropy shows a power law correlation with strain ratio where the initial susceptibility ellipsoid was nearly coaxial with the bulk strain axes during the experiment. More generally, in those situations, as well as ones in which the initial susceptibility ellipsoid was strongly inclined to the bulk strain axes there exists a common matrix M which relates the initial susceptibility tensor kij, the final susceptibility tensor k' ij and the strain tensor eij: eijk' ij = Mk' ij

  11. MAGNETIC SUSCEPTIBILITIES OF SOME RARE EARTH OXIDES.

    DTIC Science & Technology

    MAGNETIC PROPERTIES), SODIUM COMPOUNDS, MOLYBDATES, GADOLINIUM COMPOUNDS, TERBIUM COMPOUNDS, DYSPROSIUM COMPOUNDS, HOLMIUM COMPOUNDS, EUROPIUM COMPOUNDS...THULIUM COMPOUNDS, YTTERBIUM COMPOUNDS, SAMARIUM COMPOUNDS, GALLIUM COMPOUNDS, OXIDES, SINGLE CRYSTALS, ANISOTROPY, FERROMAGNETISM, ANTIFERROMAGNETISM, NUCLEAR SPINS

  12. Ac magnetic susceptibility study of in vivo nanoparticle biodistribution

    NASA Astrophysics Data System (ADS)

    Gutiérrez, L.; Mejías, R.; Barber, D. F.; Veintemillas-Verdaguer, S.; Serna, C. J.; Lázaro, F. J.; Morales, M. P.

    2011-06-01

    We analysed magnetic nanoparticle biodistribution, before and after cytokine conjugation, in a mouse model by ac susceptibility measurements of the corresponding resected tissues. Mice received repeated intravenous injections of nanoparticle suspension for two weeks and they were euthanized 1 h after the last injection. In general, only 10% of the total injected nanoparticles after multiple exposures were found in tissues. The rest of the particles may probably be metabolized or excreted by the organism. Our findings indicate that the adsorption of interferon to DMSA-coated magnetic nanoparticles changes their biodistribution, reducing the presence of nanoparticles in lungs and therefore their possible toxicity. The specific targeting of the particles to tumour tissues by the use of an external magnetic field has also been studied. Magnetic nanoparticles were observed by transmission electron microscopy in the targeted tissue and quantified by ac magnetic susceptibility.

  13. Magnetic susceptibility of tektites and some other glasses

    USGS Publications Warehouse

    Senftle, F.E.; Thorpe, A.

    1959-01-01

    The magnetic susceptibility at several magnetic field strengths of about thirty tektites from various localities have been measured. The susceptibility ranges from 2 ?? 10-6 to about 7.9 ?? 10-6 e.m.u./g. Tektites from a given locality have similar susceptibilities. The intensity of magnetization of all the tektites measured is zero or very small. For comparison, the same measurements have been made on about thirty obsidians. The magnetic susceptibilities cover approximately the same range, but the intensity of magnetization of the impurity was found to be much higher. By heating the obsidians to 1450??C the intensity of magnetization was reduced to zero. From the above data, it is shown that the tektites must have been heated well above 1400??C, and that essentially all the iron is in solution. On the other hand, the evidence shows that obsidians have not been heated much above this temperature, and that there is a significant amount of undissolved iron in the glass, probably as magnetite. Further, if tektites are extraterrestrial, they probably entered the earth's atmosphere as a glass. ?? 1959.

  14. Core loss and magnetic susceptibility of superparamagnetic Fe nanoparticle assembly

    NASA Astrophysics Data System (ADS)

    Kin, Masane; Kura, Hiroaki; Ogawa, Tomoyuki

    2016-12-01

    Toroidal-shaped high-density Fe nanoparticle assemblies (FNAs) were fabricated by molding different sized Fe nanoparticles (NPs), and the effect of the magnetic behavior of the FNAs on the core loss and the magnetic susceptibility was investigated. An FNA with 4.3 nm diameter Fe NPs exhibits superparamagnetism at room temperature while an FNA with 6.4 nm diameter Fe NPs doesn't exhibit superparamagnetism at room temperature. AC magnetization curves at 1, 10 and 100 kHz were measured to evaluate the core loss of the toroidal-shaped FNAs. Both FNAs exhibited no significant eddy current loss, which suggests that surfactants on the NP surface effectively act to electrically insulate the NPs, and the NPs are not sintered together when the FNAs are molded. The AC magnetization curves had no hysteresis for the FNA with 4.3 nm diameter Fe NPs, i.e., the core loss was minimal for the superparamagnetic FNA. The magnetic susceptibility of the superparamagnetic FNA with 4.3 nm Fe NPs was 12 times higher than that estimated from Langevin theory due to the effect of strong magnetic dipole interaction. These results suggest that the superparamagnetic FNA has potential as a magnetic core material that exhibits low core loss and high magnetic susceptibility, even at high frequency.

  15. Magnetic susceptibility and exchange coupling in the mineral ardennite

    USGS Publications Warehouse

    Thorpe, A.N.; Senftle, F.E.; Donnay, G.

    1969-01-01

    Ardennite, a rare silicate mineral, contains about 19 wt.% manganese. Some of the manganese atoms are in positions which are close enough to allow negative exchange and hence a reduction of the total magnetic susceptibility. It is shown that the susceptibility can be accounted for approximately by the treatment of Earnshaw and Lewis (1958) for S = 5 2 and a Hamiltonian H = -2g??Hb-2JS1??S2. ?? 1969.

  16. Anisotropy of magnetic susceptibility: rock composition versus strain

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham

    1987-07-01

    The shape of the susceptibility ellipsoid for a metamorphic tectonite with a strong crystallographic preferred orientation of silicates is strongly influenced by the anisotropy of the most abundant magnetic silicate in the absence of magnetite. Where traces (< 1%) of magnetite are present, inter-specimen variation in the amount of magnetite can override the effects of strain in controlling the shape of the susceptibility ellipsoid.

  17. Magnetic susceptibility fabrics in slates: Structural, mineralogical and lithological influences

    NASA Astrophysics Data System (ADS)

    Borradaile, G.; Sarvas, P.

    1990-02-01

    A single, penetrative tectonic deformation of Archean greywackes, accompanied by low grade metamorphism, generated low-field magnetic susceptibility fabrics that are coaxial with the rock's schistosity although there are multiple sources of magnetic susceptibility. Pre-metamorphic magnetite and the metamorphic minerals pyrrhotite, biotite and chlorite (variety thuringite: daphnite-aphrosiderite) are responsible for the anisotropy of susceptibility. These minerals grew with preferred crystallographic orientations influenced by the prevailing stress regime. On its own, rotation cannot be invoked to explain the alignment of the metamorphic minerals. There are varying proportions of at least two of these minerals in most specimens. For 153 specimens the degree of anisotropy increases as the mean susceptibility increases over the range from 100 to 700 (in units of 10 -6 S.I.)- Theory shows that this is to be expected either due to increasing the traces of strongly oriented ferrimagnetics or due to increasing the proportion of chlorite. In the latter case this simultaneously increased its preferred orientation by closer packing. Stress-influenced crystallization of chlorite rapidly achieves saturation alignment and a limiting magnetic anisotropy although strain may continue to increase. Samples taken through individual graded beds show that the susceptibility ellipsoid varies from oblate in slaty rocks to a neutral shape in sandier rocks. However, its orientation is always structurally controlled, with the minimum susceptibility axis perpendicular to schistosity.

  18. Correlation of strain with anisotropy of magnetic susceptibility (AMS)

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham J.

    1991-01-01

    Existing correlations between strain and anisotropy of low-field magnetic susceptibility (AMS) have been re-assessed using a single parameter to express both anisotropies. The P' parameter ( Hrouda, 1982) shows potential as a powerful single expression of the intensity of strain and of AMS. Previous correlations are improved by use of this parameter. Cautious optimism is justified for correlations between strain and susceptibility in a certain strain window between a lower limit (excluding the incomplete overprint of predeformation anisotropy) and an upper limit (excluding the effects of saturation anisotropy). For successful correlations the influence of stress-controlled recrystallisation should be minimal and the mineralogical sources of susceptibility must predate deformation.

  19. Magnetic susceptibility and isothermal remanent magnetization in human tissues: a study case.

    PubMed

    Sant'Ovaia, H; Marques, G; Santos, A; Gomes, C; Rocha, A

    2015-12-01

    This study evaluated the magnetic properties, magnetic susceptibility and isothermal remanent magnetization (IRM) of tissue samples from the brain, liver, spleen, pancreas, heart and lungs, resected from human corpses, with the aim of identifying the magnetic mineral structures and understanding their possible connection to diseases, professional activity, age and gender of the individual, smoking habits and the environment. The heart was the organ with the highest values of magnetic susceptibility and the pancreas showed the lowest values. No relationship was found between magnetic susceptibility, IRM values and ages of the individuals. However the samples obtained in females showed lower values of magnetic susceptibility than those resected from males. The samples collected from the lungs of smokers have higher values of magnetic susceptibility and IRM indicating the presence of magnetic particles with an anthropic origin. Moreover, the complexity of the magnetic behaviour of these tissues may suggest a contribution of both biogenic and anthropogenic magnetic particles also due to some professional activities. In the brain a heterogeneous distribution of the magnetic susceptibility values was found, which might be related mainly to the diamagnetic behaviour of myelin-rich structures. This study suggests that although the diamagnetic and paramagnetic behaviour is common to all structures, magnetite-type structures are always present in the tissues and hematite-type structures may also contribute to the magnetic signal of the sample. IRM values are only dependent on the presence of magnetite or hematite-type magnetic structures and so this technique seems more suitable to achieve the characterization of biomagnetic structures than magnetic susceptibility.

  20. Using triaxial magnetic fields to create high susceptibility particle composites.

    PubMed

    Martin, James E; Venturini, Eugene; Gulley, Gerald L; Williamson, Jonathan

    2004-02-01

    We report on the use of triaxial magnetic fields to create a variety of isotropic and anisotropic magnetic particle/polymer composites with significantly enhanced magnetic susceptibilities. A triaxial field is a superposition of three orthogonal ac magnetic fields, each generated by a Helmholtz coil in series resonance with a tunable capacitor bank. Field frequencies are in the range of 150-400 Hz. Because both the field amplitudes and frequencies can be varied, a rich variety of structures can be created. Perhaps the most unusual effects occur when either two or three of the field components are heterodyned to give beat frequencies on the order of 1 Hz. This leads to a striking particle dynamics that evolves into surprising structures during resin gelation. These structures are found to have perhaps the highest susceptibility that a particle composite can have. The susceptibility anisotropy of these composites can be controlled over a wide range by judicious adjustment of the relative field amplitudes. These experimental data are supported by large-scale Brownian dynamics simulations of the complex many-body interactions that occur in triaxial magnetic fields. These simulations show that athermal three-dimensional field heterodyning leads to structures with a susceptibility that is as high as that achieved with thermal annealing. Thus with coherent particle motions we can achieve magnetostatic energies that are quite close to the ground state.

  1. Geostatistical Microscale Study of Magnetic Susceptibility in Soil Profile and Magnetic Indicators of Potential Soil Pollution.

    PubMed

    Zawadzki, Jarosław; Fabijańczyk, Piotr; Magiera, Tadeusz; Rachwał, Marzena

    Directional variograms, along the soil profile, can be useful and precise tool that can be used to increase the precision of the assessment of soil pollution. The detail analysis of spatial variability in the soil profile can be also an important part of the standardization of soil magnetometry as a screening method for an assessment of soil pollution related to the dust deposition. The goal of this study was to investigate the correlation between basic parameters of spatial correlations of magnetic susceptibility in the soil profile, such as a range of correlation and a sill, and selected magnetometric indicators of soil pollution. Magnetic indicators were an area under the curve of magnetic susceptibility versus a depth in the soil profile, values of magnetic susceptibility at depths ranging from 1 to 10 cm, and maximum and background values of magnetic susceptibility in the soil profile. These indicators were previously analyzed in the literature. The results showed that a range of correlation of magnetic susceptibility was significantly correlated with magnetic susceptibility measured at depths 1, 2, and 3 cm. It suggests that a range of correlation is a good measure of pollutants' dispersion in the soil profile. The sill of the variogram of magnetic susceptibility was found to be significantly correlated with the area under the curve of plot of magnetic susceptibility that is related to the soil pollution. In consequence, the parameters of microscale spatial variability of magnetic susceptibility in s soil profile are important measures that take into consideration the spatial aspect of s soil pollution.

  2. Variable Temperature Equipment for a Commercial Magnetic Susceptibility Balance

    ERIC Educational Resources Information Center

    Lotz, Albert

    2008-01-01

    Variable temperature equipment for the magnetic susceptibility balance MSB-MK1 of Sherwood Scientific, Ltd., is described. The sample temperature is controlled with streaming air heated by water in a heat exchanger. Whereas the balance as sold commercially can be used only for room temperature measurements, the setup we designed extends the…

  3. Understanding the Magnetic Susceptibility Measurements by Using an Analytical Scale

    ERIC Educational Resources Information Center

    Cano, M. E.; Cordova-Fraga, T.; Sosa, M.; Bernal-Alvarado, J.; Baffa, O.

    2008-01-01

    A description of the measurement procedure, related theory and experimental data analysis of the magnetic susceptibility of materials is given. A short review of previous papers in the line of this subject is presented. This work covers the whole experimental process, in detail, and presents a pragmatic approach for pedagogical sake. (Contains 2…

  4. Calculation of nonlinear magnetic susceptibility tensors for a uniaxial antiferromagnet

    NASA Astrophysics Data System (ADS)

    Lim, Siew-Choo; Osman, Junaidah; Tilley, D. R.

    2000-11-01

    In this paper, we present a derivation of the nonlinear susceptibility tensors for a two-sublattice uniaxial antiferromagnet up to the third-order effects within the standard definition by which the rf magnetization m is defined as a power series expansion in the rf fields h with the susceptibility tensors χ(q) as the coefficients. The starting point is the standard set of torque equations of motion for this problem. A complete set of tensor elements is derived for the case of a single-frequency input wave. Within a circular polarization frame (pnz) expressions are given for the first-order susceptibility, second-harmonic generation, optical rectification, third-harmonic generation and intensity-dependent susceptibility. Some of the coefficients with representative resonance features in the far infrared are illustrated graphically and we conclude with a brief discussion of the implications of the resonance features arising from the calculations and their potential applications.

  5. Accuracy of MRI-based Magnetic Susceptibility Measurements

    NASA Astrophysics Data System (ADS)

    Russek, Stephen; Erdevig, Hannah; Keenan, Kathryn; Stupic, Karl

    Magnetic Resonance Imaging (MRI) is increasingly used to map tissue susceptibility to identify microbleeds associated with brain injury and pathologic iron deposits associated with neurologic diseases such as Parkinson's and Alzheimer's disease. Field distortions with a resolution of a few parts per billion can be measured using MRI phase maps. The field distortion map can be inverted to obtain a quantitative susceptibility map. To determine the accuracy of MRI-based susceptibility measurements, a set of phantoms with paramagnetic salts and nano-iron gels were fabricated. The shapes and orientations of features were varied. Measured susceptibility of 1.0 mM GdCl3 solution in water as a function of temperature agreed well with the theoretical predictions, assuming Gd+3 is spin 7/2. The MRI susceptibility measurements were compared with SQUID magnetometry. The paramagnetic susceptibility sits on top of the much larger diamagnetic susceptibility of water (-9.04 x 10-6), which leads to errors in the SQUID measurements. To extract out the paramagnetic contribution using standard magnetometry, measurements must be made down to low temperature (2K). MRI-based susceptometry is shown to be as or more accurate than standard magnetometry and susceptometry techniques.

  6. Anisotropy of magnetic susceptibility of some metamorphic minerals

    NASA Astrophysics Data System (ADS)

    Borradaile, G.; Keeler, W.; Alford, C.; Sarvas, P.

    1987-09-01

    The anisotropy of susceptibility of metamorphic rocks can be due to paramagnetic rock-forming silicates such as amphiboles, chlorites and micas. It is not always necessary to invoke fabrics of separate grains of iron oxide to explain the anisotropy. Minimum estimates of lattice anisotropies of typical samples of silicates have maximum-to-minimum ratios of 1.1-1.7. Since the magnetic anisotropies of most metamorphic rocks are less than this, these minerals can control the anisotropy of susceptibility because their preferred crystallographic orientations are usually very strong in comparison with the preferred dimensional orientation of magnetite and because they are more abundant than magnetite.

  7. Magnetic susceptibility in three-dimensional nodal semimetals

    NASA Astrophysics Data System (ADS)

    Koshino, Mikito; Hizbullah, Intan Fatimah

    2016-01-01

    We study the magnetic susceptibility in various three-dimensional gapless systems, including Dirac and Weyl semimetals, and a line-node semimetal. The susceptibility is decomposed into the orbital term, the spin term and also the spin-orbit cross term, which is caused by the spin-orbit interaction. We show that the orbital susceptibility logarithmically diverges at the band touching energy in the point-node case, while it exhibits a stronger δ -function singularity in the line node case. The spin-orbit cross term is shown to be paramagnetic in the electron side while diamagnetic in the hole side, in contrast with other two terms which are both even functions in Fermi energy. The spin-orbit cross term in the nodal semimetal is found to be directly related to the chiral surface current induced by the topological surface modes.

  8. Detecting compaction disequilibrium with anisotropy of magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Schwehr, Kurt; Tauxe, Lisa; Driscoll, Neal; Lee, Homa

    2006-11-01

    In clay-rich sediment, microstructures and macrostructures influence how sediments deform when under stress. When lithology is fairly constant, anisotropy of magnetic susceptibility (AMS) can be a simple technique for measuring the relative consolidation state of sediment, which reflects the sediment burial history. AMS can reveal areas of high water content and apparent overconsolidation associated with unconformities where sediment overburden has been removed. Many other methods for testing consolidation and water content are destructive and invasive, whereas AMS provides a nondestructive means to focus on areas for additional geotechnical study. In zones where the magnetic minerals are undergoing diagenesis, AMS should not be used for detecting compaction state. By utilizing AMS in the Santa Barbara Basin, we were able to identify one clear unconformity and eight zones of high water content in three cores. With the addition of susceptibility, anhysteretic remanent magnetization, and isothermal remanent magnetization rock magnetic techniques, we excluded 3 out of 11 zones from being compaction disequilibria. The AMS signals for these three zones are the result of diagenesis, coring deformation, and burrows. In addition, using AMS eigenvectors, we are able to accurately show the direction of maximum compression for the accumulation zone of the Gaviota Slide.

  9. Magnetic susceptibility properties of pesticide contaminated volcanic soil

    NASA Astrophysics Data System (ADS)

    Agustine, Eleonora; Fitriani, Dini; Safiuddin, La Ode; Tamuntuan, Gerald; Bijaksana, Satria

    2013-09-01

    Pesticides, unfortunately, are still widely used in many countries as way to eradicate agricultural pests. As they are being used continuously over a long period of time, they accumulate as residues in soils posing serious threats to the environment. In this study, we study the changes in magnetite-rich volcanic soils that were deliberately contaminated by pesticide. Such changes, in any, would be useful in the detection of pesticide residue in contaminated soils. Two different types of magnetically strong volcanic soil from the area near Lembang, West Java, Indonesia were used in this study where they were contaminated with varying concentrations of pesticide. The samples were then measured for magnetic susceptibility at two different frequencies. The measurements were then repeated after a period of three months. We found a reduction of magnetic susceptibility as well as a reduction in SP (superparamagnetic) grains proportion in contaminated soil. These might be caused by pesticide-induced magnetic dissolution as supported by SEM analyses. However the impact of pesticide concentration as well as exposure time on magnetic dissolution is still inconclusive.

  10. ac susceptibility study of a magnetite magnetic fluid

    NASA Astrophysics Data System (ADS)

    Ayala-Valenzuela, O. E.; Matutes-Aquino, J. A.; Galindo, J. T. Elizalde; Botez, C. E.

    2009-04-01

    Magnetite nanometric powder was synthesized from metal salts using a coprecipitation technique. The powders were used to produce magnetic fluid via a peptization method, with hydrocarbon Isopar M as liquid carrier and oleic acid as surfactant. The complex magnetic susceptibility χ =χ'+iχ″ was measured as a function of temperature T in steps of 2.5 K from 3 to 298 K for frequencies ranging from f =10 to 10 000 Hz. The magnetic fluid real and imaginary components of the ac susceptibility show a prominent maximum at temperatures that increase with the measuring frequency, which is attributed to a spin-glass-like behavior. The peak temperature Tp1 of χ″ depends on f following the Vogel-Fulcher law f =f0 exp[E /kB(Tp1-T0)], where f0 and E are positive constants and T0 is a parameter related to particle interactions. There is another kind of peak temperature, Tp2, in the loss factor tan δ =χ″/χ' which is related to a magnetic aftereffect. The peak temperature Tp2 is far less than Tp1 and shows an Arrhenius-type dependence on f.

  11. Temperature dependence of magnetic susceptibility in the vicinity of martensitic transformation in ferromagnetic shape memory alloys.

    PubMed

    Zablotskii, V; Pérez-Landazábal, J I; Recarte, V; Gómez-Polo, C

    2010-08-11

    Temperature dependences of low-field quasistatic magnetic susceptibility in the vicinity of martensitic transitions in an NiFeGa alloy are studied both by experiment and analytically. Pronounced reversible jumps of the magnetic susceptibility were observed near the martensitic transition temperature. A general description of the temperature dependences of the susceptibility in ferromagnetic austenite and martensite phases and the susceptibility jump at the transition is suggested. As a result, the main factors governing the temperature dependences of the magnetic susceptibility in the magnetic shape memory alloys are revealed. The magnetic susceptibility jump value is found to be related to changes of: (i) magnetic anisotropy; (ii) magnetic domain wall geometrical constraints (those determined by the alignment and size of twin variants) and (iii) mean magnetic domain spacing.

  12. Magnetic resonance and magnetic susceptibility study of vanadium oxide—decylamine nanotubes

    NASA Astrophysics Data System (ADS)

    Panich, Alexander M.; Felner, Israel; Shames, Alexander I.; Lee, Cheol Eui

    2016-11-01

    We report on magnetic susceptibility, 51V NMR and EPR study of multiwall vanadium oxide—decylamine nanotubes. Our measurements reveal the presence of a diamagnetic V5+ and two paramagnetic V4+ ions, respectively. NMR spectra and magnetic susceptibility data estimate the V4+ ions as ˜31%-35% of the entire vanadium ions content. EPR evidences that the paramagnetic V4+ subsystem consists of ˜10% of individual ions (hyperfine structured polycrystalline pattern) and ˜90% of exchange coupled entities (Lorentzian line).

  13. Quantification of magnetic susceptibility in several strains of Bacillus spores: implications for separation and detection.

    PubMed

    Melnik, Kristie; Sun, Jianxin; Fleischman, Aaron; Roy, Shuvo; Zborowski, Maciej; Chalmers, Jeffrey J

    2007-09-01

    Three strains of Bacillus: Bacillus atrophaeus (formally Bacillus globigii), Bacillus thuringiensis, and Bacillus cereus were tested for their intrinsic magnetic susceptibility. All three strains when sporulated demonstrated significant magnetic susceptibility using an instrument referred to as Cell Tracking Velocimetry. Energy dispersive spectroscopy also confirmed the presence of paramagnetic elements, Fe and Mn, in the spore form of the bacteria. It was demonstrated that this magnetic susceptibility is sufficient to separate and deposit these spores on glass slides in a magnetic deposition system. These results indicate the potential to separate spores with intrinsic magnetic susceptibility directly out of water or air samples.

  14. Generalized longitudinal susceptibility for magnetic monopoles in spin ice

    PubMed Central

    Bramwell, Steven T.

    2012-01-01

    The generalized longitudinal susceptibility χ(q,ω) affords a sensitive measure of the spatial and temporal correlations of magnetic monopoles in spin ice. Starting with the monopole model, a mean field expression for χ(q,ω) is derived as well as expressions for the mean square longitudinal field and induction at a point. Monopole motion is shown to be strongly correlated, and both spatial and temporal correlations are controlled by the dimensionless monopole density x which defines the ratio of the magnetization relaxation rate and the monopole hop rate. Thermal effects and spin-lattice relaxation are also considered. The derived equations are applicable in the temperature range where the Wien effect for magnetic monopoles is negligible. They are discussed in the context of existing theories of spin ice and the following experimental techniques: DC and AC magnetization, neutron scattering, neutron spin echo and longitudinal and transverse field μSR. The monopole theory is found to unify diverse experimental results, but several discrepancies between theory and experiment are identified. One of these, concerning the neutron scattering line shape, is explained by means of a phenomenological modification to the theory. PMID:23166378

  15. Spectroscopic AC Susceptibility Imaging (sASI) of Magnetic Nanoparticles.

    PubMed

    Ficko, Bradley W; Nadar, Priyanka M; Diamond, Solomon G

    2015-02-01

    This study demonstrates a method for alternating current (AC) susceptibility imaging (ASI) of magnetic nanoparticles (mNPs) using low cost instrumentation. The ASI method uses AC magnetic susceptibility measurement to create tomographic images using an array of drive coils, compensation coils and fluxgate magnetometers. Using a spectroscopic approach in conjunction with ASI, a series of tomographic images can be created for each frequency measurement and is termed sASI. The advantage of sASI is that mNPs can be simultaneously characterized and imaged in a biological medium. System calibration was performed by fitting the in-phase and out-of-phase susceptibility measurements of an mNP sample with a hydrodynamic diameter of 100 nm to a Brownian relaxation model (R(2) = 0.96). Samples of mNPs with core diameters of 10 and 40 nm and a sample of 100 nm hydrodynamic diameter were prepared in 0.5 ml tubes. Three mNP samples were arranged in a randomized array and then scanned using sASI with six frequencies between 425 and 925 Hz. The sASI scans showed the location and quantity of the mNP samples (R(2) = 0.97). Biological compatibility of the sASI method was demonstrated by scanning mNPs that were injected into a pork sausage. The mNP response in the biological medium was found to correlate with a calibration sample (R(2) = 0.97, p <0.001). These results demonstrate the concept of ASI and advantages of sASI.

  16. Spectroscopic AC susceptibility imaging (sASI) of magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Ficko, Bradley W.; Nadar, Priyanka M.; Diamond, Solomon G.

    2015-02-01

    This study demonstrates a method for alternating current (AC) susceptibility imaging (ASI) of magnetic nanoparticles (mNPs) using low cost instrumentation. The ASI method uses AC magnetic susceptibility measurements to create tomographic images using an array of drive coils, compensation coils and fluxgate magnetometers. Using a spectroscopic approach in conjunction with ASI, a series of tomographic images can be created for each frequency measurement set and is termed sASI. The advantage of sASI is that mNPs can be simultaneously characterized and imaged in a biological medium. System calibration was performed by fitting the in-phase and out-of-phase susceptibility measurements of an mNP sample with a hydrodynamic diameter of 100 nm to a Brownian relaxation model (R2=0.96). Samples of mNPs with core diameters of 10 and 40 nm and a sample of 100 nm hydrodynamic diameter were prepared in 0.5 ml tubes. Three mNP samples were arranged in a randomized array and then scanned using sASI with six frequencies between 425 and 925 Hz. The sASI scans showed the location and quantity of the mNP samples (R2=0.97). Biological compatibility of the sASI method was demonstrated by scanning mNPs that were injected into a pork sausage. The mNP response in the biological medium was found to correlate with a calibration sample (R2=0.97, p<0.001). These results demonstrate the concept of ASI and advantages of sASI.

  17. Idiopathic generalised tremor syndrome in two cats.

    PubMed

    Mauler, Daniela A; Van Soens, Iris; Bhatti, Sofie F; Cornelis, Ine; Martlé, Valentine A; Van Ham, Luc M

    2014-04-01

    Two male neutered domestic shorthair cats were evaluated for generalised tremors. On neurological examination both cats showed whole-body tremors, worsening with stress. A mainly cerebellar disorder was suspected. Blood examination, cerebrospinal fluid analysis and electrophysiological examination of both cats and magnetic resonance imaging of the brain in one cat were normal. Idiopathic generalised tremor syndrome (IGTS) was suspected owing to the exclusion of underlying causes and the clinical similarities with the syndrome in dogs. Treatment as recommended for dogs was initiated and resulted in improvement. This report describes the first cases of IGTS in cats.

  18. Effect of Anti-dots on the Magnetic Susceptibility in a Superconducting Long Prism

    NASA Astrophysics Data System (ADS)

    Aguirre, C. A.; Joya, Miryam R.; Barba-Ortega, J.

    2017-02-01

    The magnetic susceptibility of a long mesoscopic superconducting square prism containing one/two (dot) anti-dots is calculated in the framework of the Ginzburg-Landau theoretical model. This magnetic susceptibility shows jumps at each of the vortex transition fields. We studied the influence of the number, size and geometry of the anti-dots on the magnetic susceptibility in a superconducting sample. We found interesting physical behavior when several kinds of materials filled into the anti-dot are considered.

  19. Magnetic Susceptibility Effects and Lorentz Damping in Diamagnetic Fluids

    NASA Technical Reports Server (NTRS)

    Ramachandran, Narayanan; Leslie, Fred W.

    2000-01-01

    A great number of crystals (semi-conductor and protein) grown in space are plagued by convective motions which contribute to structural flaws. The character of these instabilities is not well understood but is associated with density variations in the presence of residual gravity and g-jitter. Both static and dynamic (rotating or travelling wave) magnetic fields can be used to reduce the effects of convection in materials processing. In semi-conductor melts, due to their relatively high electrical conductivity, the induced Lorentz force can be effectively used to curtail convective effects. In melts/solutions with reduced electrical conductivity, such as aqueous solutions used in solution crystal growth, protein crystal growth and/or model fluid experiments for simulating melt growth, however, the variation of the magnetic susceptibility with temperature and/or concentration can be utilized to better damp fluid convection than the Lorentz force method. This paper presents a comprehensive, comparative numerical study of the relative damping effects using static magnetic fields and gradients in a simple geometry subjected to a thermal gradient. The governing equations are formulated in general terms and then simplified for the numerical calculations. Operational regimes, based on the best damping technique for different melts/solutions are identified based on fluid properties. Comparisons are provided between the numerical results and available results from experiments in surveyed literature.

  20. Promoting and Assessing Mathematical Generalising

    ERIC Educational Resources Information Center

    Hill, Tiffany; Lannin, John; van Garderen, Delinda

    2015-01-01

    Helping students generalise mathematical ideas is an essential component of teaching and learning of mathematics (Lannin, Ellis, Elliott & Zbiek, 2011). However, it can be challenging for primary teachers to assess and promote generalisation. Because generalisation is an essential part of mathematics instruction, the authors highlight the…

  1. Measurement of magnetic susceptibility in pulsed magnetic fields using a proximity detector oscillator.

    PubMed

    Ghannadzadeh, S; Coak, M; Franke, I; Goddard, P A; Singleton, J; Manson, J L

    2011-11-01

    We present a novel susceptometer with a particularly small spatial footprint and no moving parts. The susceptometer is suitable for use in systems with limited space where magnetic measurements may not have been previously possible, such as in pressure cells and rotators, as well as in extremely high pulsed fields. The susceptometer is based on the proximity detector oscillator, which has a broad dynamic resonant frequency range and has so far been used predominantly for transport measurements. We show that for insulating samples, the resonance frequency behavior as a function of field consists of a magnetoresistive and an inductive component, originating, respectively, from the sensor coil and the sample. The response of the coil is modeled, and upon subtraction of the magnetoresistive component the dynamic magnetic susceptibility and magnetization can be extracted. We successfully measure the magnetization of the organic molecular magnets Cu(H(2)O)(5)(VOF(4))(H(2)O) and [Cu(HF(2))(pyz)(2)]BF(4) in pulsed magnetic fields and by comparing the results to that from a traditional extraction susceptometer confirm that the new system can be used to measure and observe magnetic susceptibilities and phase transitions.

  2. Power-law resistivity, magnetic relaxation and ac susceptibility

    SciTech Connect

    Gilchrist, J.; van der Beek, C.J.

    1994-07-01

    The nonlinear diffusion of magnetic flux into a superconducting sample can be studied by measuring the relaxation of the magnetisation after application of a step field or by measuring the ac susceptibility, {chi}{sub 1} and its third harmonic, {chi}{sub 3}, or preferably both methods covering different time scales. Each has been analysed recently for a field-cooled sample of a material whose creep activation energy depends logarithmically on current density, J corresponding to a power-law relation between electric field, E and J. Here, results are compared, using a universal scaling depth. Maximum {chi}{sub 1}{double_prime} {vert_bar}{chi}{sub 3}{vert_bar} and values occur, and also the magnetisation has relaxed to half its initial value when the scaling depth is comparable to the sample half-thickness.

  3. Magnetic Susceptibility Measurements as a Proxy for Hydrocarbon Biodegradation

    NASA Astrophysics Data System (ADS)

    Mewafy, F.; Atekwana, E. A.; Slater, L. D.; Werkema, D.; Revil, A.; Ntarlagiannis, D.; Skold, M.

    2011-12-01

    Magnetic susceptibility (MS) measurements have been commonly used in paleoclimate studies, as a proxy for environmental pollution such as heavy metal contamination, and for delineating zones of oil seeps related to hydrocarbon exploration. Few studies have assessed the use of MS measurements for mapping zones of oil pollution. In this study, we investigated the variation in magnetic susceptibility across a hydrocarbon contaminated site undergoing biodegradation. Our objective was to investigate if MS measurements could be used as a proxy indicator of intrinsic bioremediation linked to the activity of iron reducing bacteria. An improved understanding of the mechanisms generating geophysical signatures associated with microbial enzymatic activity could permit the development of geophysical imaging technologies for long-term, minimally invasive and sustainable monitoring of natural biodegradation at oil spill sites. We used a Bartington MS probe to measure MS data along fifteen boreholes within contaminated (both free phase and dissolved phase hydrocarbon plumes) and clean areas. Our results show the following: (1) an enhanced zone of MS straddling the water table at the contaminated locations, not observed at the clean locations; (2) MS values within the free product plume are higher compared to values within the dissolved product plume; (3) the MS values within the vadoze zone above the free product plume are higher compared to values within the dissolved product plume; 4) the zone of high MS is thicker within the free product plume compared to the dissolved product plume. We suggest that the zone of enhanced MS results from the precipitation of magnetite related to the oxidation of the hydrocarbons coupled to iron reduction. Our data documents a strong correlation between MS and hydrocarbon concentration. We conclude that recognition of these zones of enhanced magnetite formation allows for the application of MS measurements as a: (1) low cost, rapid monitoring

  4. Magnetic susceptibility and magnetic resonance measurements of the moisture content and hydration condition of a magnetic mixture material

    SciTech Connect

    Tsukada, K. Kusaka, T.; Saari, M. M.; Takagi, R.; Sakai, K.; Kiwa, T.; Bito, Y.

    2014-05-07

    We developed a magnetic measurement method to measure the moisture content and hydration condition of mortar as a magnetic mixture material. Mortar is a mixture of Portland cement, sand, and water, and these materials exhibit different magnetic properties. The magnetization–magnetic field curves of these components and of mortars with different moisture contents were measured, using a specially developed high-temperature-superconductor superconducting quantum interference device. Using the differences in magnetic characteristics, the moisture content of mortar was measured at the ferromagnetic saturation region over 250 mT. A correlation between magnetic susceptibility and moisture content was successfully established. After Portland cement and water are mixed, hydration begins. At the early stage of the hydration/gel, magnetization strength increased over time. To investigate the magnetization change, we measured the distribution between bound and free water in the mortar in the early stage by magnetic resonance imaging (MRI). The MRI results suggest that the amount of free water in mortar correlates with the change in magnetic susceptibility.

  5. Controlling the magnetic susceptibility in an artificial elliptical quantum ring by magnetic flux and external Rashba effect

    SciTech Connect

    Omidi, Mahboubeh Faizabadi, Edris

    2015-03-21

    Magnetic susceptibility is investigated in a man-made elliptical quantum ring in the presence of Rashba spin-orbit interactions and the magnetic flux. It is shown that magnetic susceptibility as a function of magnetic flux changes between negative and positive signs periodically. The periodicity of the Aharonov-Bohm oscillations depends on the geometry of the region where magnetic field is applied, the eccentricity, and number of sites in each chain ring (the elliptical ring is composed of chain rings). The magnetic susceptibility sign can be reversed by tuning the Rashba spin-orbit strength as well. Both the magnetic susceptibility strength and sign can be controlled via external spin-orbit interactions, which can be exploited in spintronics and nanoelectronics.

  6. Impact of wastewater application on magnetic susceptibility in Terric Histosol soil

    NASA Astrophysics Data System (ADS)

    Sokołowska, Zofia; Alekseev, Andrey; Skic, Kamil; Brzezińska, Małgorzata

    2016-01-01

    In this work, we attempted to analyse the changes in magnetic susceptibility in Terric Histosol soil irrigated with municipal wastewater in a period of four years. Effects of different plants (poplar and willow), wastewater doses, depths, as well as the concentration of the elements and the total carbon content were tested. The study showed that systematic wastewater irrigation diminished magnetic susceptibility values in the top layer of soil. However, statistical analysis revealed that both doses of wastewater and growing plants did not have a significant impact on the magnetic susceptibility of obtained results. Magnetic susceptibility decreased significantly with the depth, in accordance with higher total carbon and lower content of magnetic particles. High correlation coefficients were found between magnetic susceptibility and Zn, Al2O3, Fe2O3, MnO content, whereas no correlation was observed for Cr, as well as for Pb.

  7. Magnetic Susceptibility Cyclostratigraphy of the Ediacaran Wonoka Formation, South Australia, from a Portable Susceptibility Meter

    NASA Astrophysics Data System (ADS)

    Minguez, D. A.; Kodama, K. P.

    2014-12-01

    We present the results of a rock magnetic cyclostratigraphy of the Ediacaran Wonoka Fm., from the Flinders Ranges, South Australia. The Wonoka Fm. records the Shuram C-isotope excursion, and the results of this study provide an estimate of its duration. Measurements of magnetic susceptibility (MS) were made in the field with a portable susceptibility meter (GF Instruments SM-20) every 0.4 m over 600 m of dominantly carbonate stratigraphic section, with a 100 meter interval of fine sand turbidites. We filter the data series to pass wavelengths shorter than 300 meters (the Rayleigh frequency for our data series) and use Multi Taper Method (MTM) time series analysis to estimate the power spectrum of the series. We fit a red noise model to the MTM spectrum and calculate 99% chi squared confidence limits to identify cycles with statistical significance. Unambiguous spectral peaks rise above the 99% confidence level with wavelengths of 116.9 m, 45.5 m, 23.1 m, 7.0 m, 2.5 m, 1.7 m, 1.3 m, 1.2 m, 0.9 m, and 0.8 m. Haines (1988, Sed. Geo. V 58) recognizes cycles in clastic sediment delivery to the carbonate portions of the Wonoka with an average wavelength of 8 m and hypothesizes a climate driver related to Milankovitch cycles. The 7 m cycle in MS is likely a more precise measure of the same phenomenon. Furthermore, cycles with wavelengths of 24.1 m, 7.0 m, 1.7m, 1.26 m, and 0.9 m exhibit ratios matching modeled durations of long eccentricity (405 kyr), short eccentricity (123 kyr), obliquity (29 kyr), and the 2 periods of precession (19 and 14 kyr) for the late Neoproterozoic. This interpretation yields a duration of 10 Myr for the 600 m we sampled. Assuming a constant sedimentation rate yields an 11.3 Myr estimate for the ~675 m thick Shuram C-isotope excursion. However, uncertainty lies in applying the MTM-based estimate to the turbidite section. Our estimate will be refined and compared with laboratory rock magnetic measurements in an ongoing study of the Wonoka Fm.

  8. Tectonic applications of magnetic susceptibility and its anisotropy

    NASA Astrophysics Data System (ADS)

    Borradaile, G. J.; Henry, B.

    1997-03-01

    Anisotropy of low field magnetic susceptibility (AMS) is a versatile petrofabric tool. For magnetite, AMS primarily defines grain-shape anisotropy; for other minerals, AMS expresses crystallographic control on magnetic properties. Thus, we may infer the orientation-distribution of a dominant mineral from the AMS of a rock. AMS principal directions can record current directions from sediment, flow-directions from magma, finite-strain directions from tectonized rocks and stress-directions from low-strain, low-temperature, neotectonic environments. AMS measurements may reveal some aspects of the strain-path, where carefully selected. For example, we may compare different parts of a heterogeneously strained domain, different minerals in a homogeneously strained site, AMS with schistosity/mineral lineation, and AMS with remanence-anisotropy. Such measurements isolate the orientation-distributions of different minerals, adding a temporal scale to the kinematic sequence. Normally, we can interpret the principal directions of AMS distributions as a physically significant direction, such as a current direction, magmatic flow or finite-strain axis. However, calibrating the AMS ellipsoid shape against the magnitude of the controlling physical process is very difficult. Primarily, this is because the shape of the AMS ellipsoid combines contributions from several minerals whose individual AMS ellipsoids are of different shape. Thus, small variations in the proportions of minerals change the shape of the rock's AMS ellipsoid, even if the alignment process were of constant intensity. In deformed rocks, AMS is more strain-sensitive than calcite twinning or the alignment of calcite or quartz c-axes. Not all AMS fabrics relate to crystallographic or grain alignment. First, displacement fabrics generate AMS where an isotropic matrix of high susceptibility displaces unevenly spaced objects of low susceptibility and suitable scales. Second, AMS location fabrics occur where sub

  9. Unusual hysteresis in the magnetic susceptibility of cubic hexaboride KB6.

    PubMed

    Etourneau, J; Ammar, A; Villesuzanne, A; Villeneuve, G; Chevalier, B; Whangbo, M-H

    2003-07-14

    Electrical resistivity, magnetic susceptibility, and electron paramagnetic resonance measurements were carried out for cubic hexaboride KB(6), which is one electron short of completely filling its conduction band. It is found that KB(6) is not metallic and has localized spins. KB(6) exhibits a highly unusual hysteresis in the magnetic susceptibility below 100 K, which suggests that it undergoes a slow relaxation process.

  10. Approximate relationship of coal bed methane and magnetic characteristics of rock via magnetic susceptibility logging

    NASA Astrophysics Data System (ADS)

    Zhao, Yonghui; Wu, Jiansheng; Zhang, Pingsong; Xiao, Pengfei

    2012-02-01

    In coal bed methane (CBM) exploration, how to improve the accuracy for locating and evaluating the CBM deposits is still a problem due to the rarity of occurrence of CBM. Combined with the distribution of the CBM content in the Huainan coalfield, the approximate relationship between the occurrence of CBM and the magnetic properties of the coal bed and adjacent mudstone have been widely discussed by magnetic logging. Experimental results show that magnetic susceptibility of the coal bed and adjacent mudstone would clearly increase with the CBM content in a coal bed. According to the results of the experiment, the prediction of the CBM content has been accomplished for different coal beds, and the results are consistent with the distribution of the CBM content throughout the whole coalfield. Preliminary data analysis reveals that there is indeed a correlation between the changes of magnetic rock characteristics and the occurrence of the CBM, and this finding may shed some light on the evaluation of CBM.

  11. The influence of radioactive decay on actinide magnetic susceptibility measurements obtained using the Evans method.

    PubMed

    Autillo, Matthieu; Kaden, Peter; Geist, Andreas; Guerin, Laetitia; Moisy, Philippe; Berthon, Claude

    2014-05-14

    In order to explain the higher magnetic susceptibility of some aquo actinide ions than predicted by Hund's rules, the molar magnetic susceptibilities of two americium isotopes ((241)Am and (243)Am) were measured using the Evans method. The results obtained show a growing change in the magnetic susceptibility with α and also a β(-) activity increase in solution. β(-) particle effects appear to be stronger than radicals formed by α particles on the experimental values. The temperature dependence of Am(iii) magnetic susceptibility has been observed but from experiments carried out here, it appears to be difficult to prove whether this effect arises from radicals or β(-). Finally, magnetic susceptibilities of americium recorded in different media (HClO4, HCl, and HNO3) have been compared to alpha and beta emissions' impact.

  12. Some factors affecting an increase in magnetic susceptibility of cement dusts

    NASA Astrophysics Data System (ADS)

    Gołuchowska, Beata J.

    2001-09-01

    The aim of the research was to explain reasons of fluctuation in magnetic susceptibility of cement dusts and the consequences for the environment. The research comprised measurements of magnetic susceptibility and Fe content in dusts, and also in raw materials, additives, fuels, mixtures and clinkers used for cement production. The samples were taken in four cement plants located in Opole Province (southern Poland). In addition to this, the influence of two production methods (dry and wet) on magnetic susceptibility of dusts and some aspects of ferrimagnetic minerals formation in the process of clinker burning were considered. It was proven that magnetic susceptibility of dusts depends on raw materials and fuels but especially on additives used for cement production, method of production and the carbon monoxide content in gases from clinker rotary kilns. Statistically important linear correlations between magnetic susceptibility and Fe suggest that during clinker burning, ferrimagnetic minerals may be formed.

  13. Three-dimensional quantification of susceptibility artifacts from various metals in magnetic resonance images.

    PubMed

    Imai, Haruki; Tanaka, Yoji; Nomura, Naoyuki; Tsutsumi, Yusuke; Doi, Hisashi; Kanno, Zuisei; Ohno, Kikuo; Ono, Takashi; Hanawa, Takao

    2013-09-01

    Susceptibility artifacts generated in magnetic resonance (MR) images were quantitatively evaluated for various metals using a three-dimensional (3-D) artifact rendering to demonstrate the correlation between magnetic susceptibility and artifact volume. Ten metals (stainless steel, Co-Cr alloy, Nb, Ti, Zr, Mo, Al, Sn, Cu and Ag) were prepared, and their magnetic susceptibilities measured using a magnetic balance. Each metal was embedded in a Ni-doped agarose gel phantom and the MR images of the metal-containing phantoms were taken using 1.5 and 3.0 T MR scanners under both fast spin echo and gradient echo conditions. 3-D renderings of the artifacts were constructed from the images and the artifact volumes were calculated for each metal. The artifact volumes of metals decreased with decreasing magnetic susceptibility, with the exception of Ag. Although Sn possesses the lowest absolute magnetic susceptibility (1.8×10(-6)), the artifact volume from Cu (-7.8×10(-6)) was smaller than that of Sn. This is because the magnetic susceptibility of Cu was close to that of the agarose gel phantom (-7.3×10(-6)). Since the difference in magnetic susceptibility between the agarose and Sn is close to that between the agarose and Ag (-17.5×10(-6)), their artifact volumes were almost the same, although they formed artifacts that were reversed in all three dimensions.

  14. Application of broadband alternating current magnetic susceptibility to the characterization of magnetic nanoparticles in natural materials

    NASA Astrophysics Data System (ADS)

    Kodama, Kazuto

    2013-01-01

    A new method is proposed for characterizing magnetic particles by measuring low-field alternating current magnetic susceptibility at a number of frequency steps spanning four orders of magnitude, from 125 Hz to 512 kHz. This method was tested using natural samples with various grain size distributions, including basalt (Kilauea, Hawaii), loess and paleosol (Luochuan, China), tuff (Yucca Mountain, Nevada), granite (Minnesota Valley, Minnesota), and andesite (Sakurajima, Japan). The resulting frequency spectrum of magnetic susceptibility (FSMS) of the basalt, loess/paleosol, and tuff decreases with increasing frequency, but at different rates of decrease. The FSMS of the basalt is characterized by a monotonic decrease with increasing frequency over the entire range. The FSMS of the loess/paleosol and the tuff decreases more markedly than that of the basalt, which agrees with previous results showing that superparamagnetic particles are dominant in such material. Quantitative estimates using FSMSs allow reconstruction of characteristic grain size distributions and clearly identify differences in the distribution of superparamagnetic particles. The multidomain granite sample has no distinct frequency dependence, which is probably due to the smooth displacement of domain walls in the presence of the external field. In contrast, the FSMSs of the andesite samples exhibit maxima over a limited frequency range, between 16 and 128 kHz. This behavior, together with low-temperature measurements, can be accounted for by magnetic resonance of domain walls in the multidomain phenocrysts.

  15. Support Vector Machines and Generalisation in HEP

    NASA Astrophysics Data System (ADS)

    Bethani, A.; Bevan, A. J.; Hays, J.; Stevenson, T. J.

    2016-10-01

    We review the concept of support vector machines (SVMs) and discuss examples of their use. One of the benefits of SVM algorithms, compared with neural networks and decision trees is that they can be less susceptible to over fitting than those other algorithms are to over training. This issue is related to the generalisation of a multivariate algorithm (MVA); a problem that has often been overlooked in particle physics. We discuss cross validation and how this can be used to improve the generalisation of a MVA in the context of High Energy Physics analyses. The examples presented use the Toolkit for Multivariate Analysis (TMVA) based on ROOT and describe our improvements to the SVM functionality and new tools introduced for cross validation within this framework.

  16. Magnetic susceptibility for a two-channel Anderson model

    NASA Astrophysics Data System (ADS)

    Líbero, Valter L.; Ferreira, João V. B.; Oliveira, Luiz N.; Cox, Daniel L.

    2001-03-01

    Non-Fermi-liquid magnetic properties are studied using a generalized two-channel Anderson model suitable for compounds like U_xTh_1-xRu_2Si2 or La_1-xCe_xCu_2.2Si2 in the low concentration regime, for which single-site characteristics of the f-electrons are experimentally evident^1. The model encompasses a spin doublet and two (degenerate) channel doublets as impurity levels, opening two channels in the conduction band, with hybridization strength V1 and V_2. The interleaving Numerical Renormalization Group procedure^2,3 determines the temperature-dependent susceptibility \\chi. For the isotropic case V_1=V2 non-Fermi liquid behavior, \\chi ≈ -ln T, is obtained. This non-trivial fixed-point, however, is unstable against channel anisotropy: for V1 ne V2 normal-Fermi liquid behavior is recovered. 1- Tae-Suk Kim and D. L. Cox, Phys. Rev. Lett. 75, 1622 (1995). 2- S. C. Costa, C. A. Paula, V. L. Líbero and L. N. Oliveira, Phys. Rev. B 55, 30 (1997). 3- J. V. B. Ferreira and V. L. Líbero, Phys. Rev. B 61, 10615 (2000).

  17. AC Magnetic Properties of Large Volume of Water — Susceptibility Measurement in Unshielded Environment

    NASA Astrophysics Data System (ADS)

    Tsukada, Keiji; Kiwa, Toshihiko; Masuda, Yuuki

    2006-10-01

    To investigate the effect of low-frequency magnetic-field exposure of a human body, the low-frequency AC magnetic property of a large volume of water was measured by low-frequency magnetic field exposure (from 50 Hz to 1.2 kHz). The results indicate that the AC magnetic property of water is due to diamagnetism in the low-frequency range. The phase between the main magnetic field and the generated magnetic field remained constant at about 180°. Results were not affected by conductivity or pH. Moreover, the magnetic-field strength from water showed a susceptibility frequency dependence proportional to the frequency above approximately 400 Hz. Because of the incremental effects of susceptibility, the magnetic field from water was measured using a conventional magnetic sensor (magnetic resistive; MR) in an unshielded environment.

  18. Non-Magnetic Factors Affecting Magnetic Susceptibility of the Loess-Paleosol Sequences in the Chinese Loess Plateau

    NASA Astrophysics Data System (ADS)

    Wang, H.; Feng, Z.

    2009-12-01

    Several different proposals have been adopted to explain the linkage between the magnetic susceptibility of loess-paleosol sequences and the associated past climate. First, the intensity of dustfall controlled the variation in the susceptibility. Second, the degree of pedogenesis controlled the variation. A third proposal states that the susceptibility signal is a result of the competing processes between pedogenic enhancement and detrital inheritance. This paper examines the acceptability as the summer monsoon proxy from nonmagnetic perspectives. Several conclusions can be drawn from our data. First, clay translocation within the Last Interglacial paleosol S1 profiles must have moved some of the magnetic minerals downward so that the susceptibility reflects only the post-translocation distribution of the magnetic susceptibility-producing minerals. Second, the best-developed paleosol S1S3 (equivalent to MIS 5e) at most of the sections studied is not well expressed by the magnetic susceptibility because this paleosol developed in underlying coarse loess (L2) and coarse textures tend to lower the susceptibility. Third, carbonate concentration is negatively correlated with the magnetic susceptibility or suppresses the magnetic susceptibility peak when the susceptibility enhancement exceeds the carbonate dilution effect. It should be stressed that the susceptibility signal and its contributors in eolian sequences can be site- and time-dependent within the Chinese Loess Plateau. A stronger eolian component northwestward and a stronger pedogenic component southeastward are the general trends, but the trends can be complicated by those site- and time-dependent factors. Therefore, a more comprehensive model is needed to more precisely address the relationship between the paleoclimate and the proxy.

  19. Quantum renormalizations in anisotropic multisublattice magnets and the modification of magnetic susceptibility under irradiation

    SciTech Connect

    Val’kov, V. V. Shustin, M. S.

    2015-11-15

    The dispersion equation of a strongly anisotropic one-dimensional magnet catena-[Fe{sup II}(ClO{sub 4}){sub 2}(Fe{sup III}(bpca){sub 2})]ClO{sub 4} containing alternating high-spin (HS) (S = 2) and low-spin (LS) (S = 1/2) iron ions is obtained by the diagram technique for Hubbard operators. The analysis of this equation yields six branches in the excitation spectrum of this magnet. It is important that the crystal field for ions with spin S = 2 is described by the Hamiltonian of single-ion easy-plane anisotropy, whose orientation is changed by 90° when passing from one HS iron ion to another. The U(N) transformation technique in the atomic representation is applied to diagonalize a single-ion Hamiltonian with a large number of levels. It is shown that the modulation of the orientation of easy magnetization planes leads to a model of a ferrimagnet with easy-axis anisotropy and to the formation of energy spectrum with a large gap. For HS iron ions, a decrease in the mean value of the spin projection due to quantum fluctuations is calculated. The analysis of the specific features of the spectrum of elementary excitations allows one to establish a correspondence to a generalized Ising model for which the magnetic susceptibility is calculated in a wide range of temperatures by the transfer-matrix method. The introduction of a statistical ensemble that takes into account the presence of chains of different lengths and the presence of iron ions with different spins allows one to describe the experimentally observed modification of the magnetic susceptibility of the magnet under optical irradiation.

  20. Quantum renormalizations in anisotropic multisublattice magnets and the modification of magnetic susceptibility under irradiation

    NASA Astrophysics Data System (ADS)

    Val'kov, V. V.; Shustin, M. S.

    2015-11-01

    The dispersion equation of a strongly anisotropic one-dimensional magnet catena-[FeII(ClO4)2{FeIII(bpca)2}]ClO4 containing alternating high-spin (HS) ( S = 2) and low-spin (LS) ( S = 1/2) iron ions is obtained by the diagram technique for Hubbard operators. The analysis of this equation yields six branches in the excitation spectrum of this magnet. It is important that the crystal field for ions with spin S = 2 is described by the Hamiltonian of single-ion easy-plane anisotropy, whose orientation is changed by 90° when passing from one HS iron ion to another. The U( N) transformation technique in the atomic representation is applied to diagonalize a single-ion Hamiltonian with a large number of levels. It is shown that the modulation of the orientation of easy magnetization planes leads to a model of a ferrimagnet with easy-axis anisotropy and to the formation of energy spectrum with a large gap. For HS iron ions, a decrease in the mean value of the spin projection due to quantum fluctuations is calculated. The analysis of the specific features of the spectrum of elementary excitations allows one to establish a correspondence to a generalized Ising model for which the magnetic susceptibility is calculated in a wide range of temperatures by the transfer-matrix method. The introduction of a statistical ensemble that takes into account the presence of chains of different lengths and the presence of iron ions with different spins allows one to describe the experimentally observed modification of the magnetic susceptibility of the magnet under optical irradiation.

  1. Collaborative Generalisation: Formalisation of Generalisation Knowledge to Orchestrate Different Cartographic Generalisation Processes

    NASA Astrophysics Data System (ADS)

    Touya, Guillaume; Duchêne, Cécile; Ruas, Anne

    Cartographic generalisation seeks to summarise geographical information from a geographic database to produce a less detailed and readable map. This paper deals with the problem of making different automatic generalisation processes collaborate to generalise a complete map. A model to orchestrate the generalisation of different areas (cities, countryside, mountains) by different adapted processes is proposed. It is based on the formalisation of cartographic knowledge and specifications into constraints and rules sets while processes are described to formalise their capabilities. The formalised knowledge relies on generalisation domain ontology. For each available generalisation process, the formalised knowledge is then translated into process parameters by an adapted translator component. The translators allow interoperable triggers and allow the choice of the proper process to apply on each part of the space. Applications with real processes illustrate the usability of the proposed model.

  2. Establishment and implications of a characterization method for magnetic nanoparticle using cell tracking velocimetry and magnetic susceptibility modified solutions.

    PubMed

    Zhang, Huading; Moore, Lee R; Zborowski, Maciej; Williams, P Stephen; Margel, Shlomo; Chalmers, Jeffrey J

    2005-04-01

    Magnetic micro and nanoparticles conjugated to affinity labels have become a significant, commercial reagent. It has been demonstrated that the performance of cell separation systems using magnetic labels is a function of the magnitude of the magnetic force that can be generated through labeling. This magnetic force is proportional to the number of magnetic particles bound to the cell, the magnetic energy gradient, and the particle-field interaction parameter. This particle-field interaction parameter, which is the product of the relative volumetric, magnetic susceptibility and the volume of the micro or nanoparticle, is a fundamental parameter which can be used to characterize the magnetic particles. An experimental technique is presented which measures the volumetric magnetic susceptibility of particles through the use of susceptibility modified solutions and an experimental instrument, Cell Tracking Velocimetry, CTV. Experimental studies were conducted on polystyrene microspheres alone and those bound to four different magnetic nanoparticles. The experimentally determined values of the magnetic susceptibility of the polystyrene microspheres are consistent with values found from literature. Consequently, magnetic susceptibility measurements of these polystyrene microspheres bound with the magnetic nanoparticles combined with particle size measurements using commercial dynamic light scattering instrument allowed estimates of the particle-field interaction parameter to be made for four commercial, magnetic nanoparticles. The value found for MACS beads is close to what is reported from an independent study. The values for MACS beads and Imag beads are found to agree with what is observed from experiments. Finally, an experimental demonstration of the impact that differences in this field interaction parameter has on the labeling of human lymphocytes is presented.

  3. Classification of soil magnetic susceptibility and prediction of metal detector performance: case study of Angola

    NASA Astrophysics Data System (ADS)

    Preetz, Holger; Altfelder, Sven; Hennings, Volker; Igel, Jan

    2009-05-01

    Soil magnetic properties can seriously impede the performance of metal detectors used in landmine clearance operations. For a proper planning of clearance operations pre-existing information on soil magnetic susceptibility can be helpful. In this study we briefly introduce a classification system to assess soil magnetic susceptibilities from geoscientific maps. The classification system is based on susceptibility measurements conducted on archived lateritic soil samples from 15 tropical countries. The system is applied to a soil map of Angola, resulting in a map that depicts soil magnetic susceptibilities as a worst case scenario. An additional layer depicting the surveyed mine affected communities in Angola is added to the map, which demonstrates that a large number of those are located in areas where soil is expected to impede metal detector performance severely.

  4. Magnetic susceptibility variations in Loess sequences and their relationship to astronomical forcing

    NASA Technical Reports Server (NTRS)

    Verosub, Kenneth L.; Singer, Michael J.

    1992-01-01

    The long, well-exposed and often continuous sequences of loess found throughout the world are generally thought to provide an excellent opportunity for studying long-term, large-scale environmental change during the last few million years. In recent years, the most fruitful loess studies have been those involving the deposits of the loess in China. One of the most intriguing results of that work has been the discovery of an apparent correlation between variations in the magnetic susceptibility of the loess sequence and the oxygen isotope record of the deep sea. This correlation implies that magnetic susceptibility variations are being driven by astronomical parameters. However, the basic data have been interpreted in various ways by different authors, most of whom assumed that the magnetic minerals in the loess have not been affected by post-depositional processes. Using a chemical extraction procedure that allows us to separate the contribution of secondary pedogenic magnetic minerals from primary inherited magnetic minerals, we have found that the magnetic susceptibility of the Chinese paleosols is largely due to a pedogenic component which is present to a lesser degree in the loess. We have also found that the smaller inherited component of the magnetic susceptibility is about the same in the paleosols and the loess. These results demonstrate the need for additional study of the processes that create magnetic susceptibility variations in order to interpret properly the role of astronomical forcing in producing these variations.

  5. Correlation of AC Loss Data from Magnetic Susceptibility Measurements with YBCO Film Quality (Postprint)

    DTIC Science & Technology

    2012-02-01

    excimer laser operating at the KrF, 248 nm , wavelength. Substrates included LaAlO3 ( 100 ) and SrTiO3 ( 100 ) single crystal substrates as well as buffered...AFRL-RZ-WP-TP-2012-0100 CORRELATION OF AC LOSS DATA FROM MAGNETIC SUSCEPTIBILITY MEASUREMENTS WITH YBCO FILM QUALITY (POSTPRINT) Paul N...CORRELATION OF AC LOSS DATA FROM MAGNETIC SUSCEPTIBILITY MEASUREMENTS WITH YBCO FILM QUALITY (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT

  6. The magnetic susceptibility on the transverse antiferromagnetic Ising model: Analysis of the reentrant behavior

    NASA Astrophysics Data System (ADS)

    Neto, Minos A.; de Sousa, J. Ricardo; Padilha, Igor T.; Rodriguez Salmon, Octavio D.; Roberto Viana, J.; Dinóla Neto, F.

    2016-06-01

    We study the three-dimensional antiferromagnetic Ising model in both uniform longitudinal (H) and transverse (Ω) magnetic fields by using the effective-field theory (EFT) with finite cluster N = 1 spin (EFT-1). We analyzed the behavior of the magnetic susceptibility to investigate the reentrant phenomena that we have seen in the same phase diagram previously obtained in other papers. Our results shows the presence of two divergences in the susceptibility that indicates the existence of a reentrant behavior.

  7. Microstructure and magnetic susceptibility of as-cast Zr-Mo alloys.

    PubMed

    Suyalatu; Nomura, Naoyuki; Oya, Kei; Tanaka, Yuko; Kondo, Ryota; Doi, Hisashi; Tsutsumi, Yusuke; Hanawa, Takao

    2010-03-01

    The microstructures and magnetic susceptibilities of Zr-Mo alloys were investigated to develop a Zr alloy with a low magnetic susceptibility for magnetic resonance imaging (MRI). The microstructure was evaluated with an X-ray diffractometer (XRD), an optical microscope (OM) and a transmission electron microscope (TEM), and the magnetic susceptibility was measured with a magnetic susceptibility balance. The alpha' phase with acicular structure was dominant in Zr-1Mo alloys, while the omega and beta phases with the equiaxed and relatively flat (no acicular) microstructure was dominant in Zr-3Mo. The mixed microstructural features of Zr-1Mo and Zr-3Mo were observed in Zr-2Mo, which consists of the alpha', omega and beta phases. The beta phase is stabilized when the Mo content exceeds over 3 mass% Mo. As-cast Zr-Mo alloys showed a minimum value of magnetic susceptibility at 3 mass% Mo, and the value abruptly increased up to 10% Mo before remaining stable up to 15 mass% Mo. XRD, OM and TEM revealed that the minimum value of the susceptibility was closely related to the appearance of the athermal omega phase in the beta phase. As the Mo content decreases from 3 mass%, the alpha' phase appears with the omega and beta phases. On the other hand, as the Mo content increases from 3 mass%, the beta phase increases and the omega phase decreases. Thus the appearance of the alpha' and beta phase leads to an increase in magnetic susceptibility. The magnetic susceptibility of as-cast Zr-3Mo alloy was almost one-third that of Ti-6Al-4V, which is commonly used for medical implant devices. Zr-Mo alloys are useful for medical devices used under MRI.

  8. Magnetic field dependent polarizability and electric field dependent diamagnetic susceptibility of a donor in Si

    NASA Astrophysics Data System (ADS)

    Muthukrishnaveni, M.; Srinivasan, N.

    2016-09-01

    The polarizability and diamagnetic susceptibility values of a shallow donor in Si are computed. These values are obtained for the cases bar{E}allel bar{B} and bar{E} bot bar{B}. The anisotropy introduced by these perturbations are properly taken care of in the expressions derived for polarizability and magnetic susceptibility. Our results show that the numerical value of the contribution from electric field to diamagnetic susceptibility is several orders smaller than that of the magnetic field effect. Polarizability values are obtained in a magnetic field by two different methods. The polarizability values decrease as the intensity of magnetic field increases. Using the Clausius-Mossotti relation, the anisotropic values of the refractive indices for different magnetic fields are estimated.

  9. Acute generalised exanthematous pustulosis.

    PubMed

    Fernando, Suran L

    2012-05-01

    Acute generalised exanthematous pustulosis (AGEP) is a severe cutaneous adverse reaction and is caused by drugs in >90% of cases. It is rare, with an incidence of 1-5 patients per million per year. The clinical manifestations are characterised by fever and the rapid appearance of disseminated sterile pustules 3-5 days after the commencement of treatment. It is accompanied by marked neutrophilia. Mucous membranes are not typically involved. The drugs conferring the highest risk of AGEP according to the EuroSCAR study are aminopenicillins, pristinamycin, hydroxychloroquine, antibacterial sulphonamides, terbinafine and diltiazem. The pathogenesis of AGEP involves the initial influx of CD8 cytotoxic T-cells resulting in the apoptosis of keratinocytes and formation of vesicles. Then CXCL-8-producing and granulocyte macrophage-colony stimulating factor-producing CD4 cells enter the epidermis, resulting in neutrophil mediated inflammation and the formation of pustules. As a result, the histology reveals intraepidermal, usually subcorneal, pustules and an accompanying neutrophilic and lymphocytic infiltrate. Epicutaneous patch testing may also support the diagnosis by causing a localised pustular reaction 48-96 h after the offending drug is applied. The condition usually resolves by 15 days after the causative drug is withdrawn but oral corticosteroid therapy may be necessary in some individuals. The mortality rate is up to 5% and mostly occurs in elderly people who have significant comorbidities.

  10. Paleoclimatic forcing of magnetic susceptibility variations in Alaskan loess during the late Quaternary

    SciTech Connect

    Beget, J.E.; Stone, D.B.; Hawkins, D.B. )

    1990-01-01

    Visual matches and statistical tests suggest correlations between marine isotope curves, retrodictive solar insolation at lat 65{degree}N, and magnetic susceptibility profiles through late Quaternary age Alaskan loess sections. The susceptibility changes largely appear to reflect variability in magnetite content due to climatically controlled changes in wind intensity and competence. Magnetic susceptibility profiles through massive loess can provide stratigraphic context for intercalated paleosols and tephras. A prominent paleosol correlated with marine isotope stage 5 occurs several metres above the Old Crow ash in loess sections, indicating that this important tephra is older than suggested by thermoluminescence dates, and may have been deposited ca. 215 {plus minus}25 ka.

  11. Quantitative susceptibility mapping (QSM): Decoding MRI data for a tissue magnetic biomarker.

    PubMed

    Wang, Yi; Liu, Tian

    2015-01-01

    In MRI, the main magnetic field polarizes the electron cloud of a molecule, generating a chemical shift for observer protons within the molecule and a magnetic susceptibility inhomogeneity field for observer protons outside the molecule. The number of water protons surrounding a molecule for detecting its magnetic susceptibility is vastly greater than the number of protons within the molecule for detecting its chemical shift. However, the study of tissue magnetic susceptibility has been hindered by poor molecular specificities of hitherto used methods based on MRI signal phase and T2* contrast, which depend convolutedly on surrounding susceptibility sources. Deconvolution of the MRI signal phase can determine tissue susceptibility but is challenged by the lack of MRI signal in the background and by the zeroes in the dipole kernel. Recently, physically meaningful regularizations, including the Bayesian approach, have been developed to enable accurate quantitative susceptibility mapping (QSM) for studying iron distribution, metabolic oxygen consumption, blood degradation, calcification, demyelination, and other pathophysiological susceptibility changes, as well as contrast agent biodistribution in MRI. This paper attempts to summarize the basic physical concepts and essential algorithmic steps in QSM, to describe clinical and technical issues under active development, and to provide references, codes, and testing data for readers interested in QSM.

  12. Dynamic magnetic susceptibility of systems with long-range magnetic order

    SciTech Connect

    Vannette, Matthew Dano

    2009-01-01

    The utility of the TDR as an instrument in the study of magnetically ordered materials has been expanded beyond the simple demonstration purposes. Results of static applied magnetic field dependent measurements of the dynamic magnetic susceptibility, χ, of various ferromagnetic (FM) and antiferromagnetic (AFM) materials showing a range of transition temperatures (1-800 K) are presented. Data was collected primarily with a tunnel diode resonator (TDR) at different radio-frequencies (~10-30 MHz). In the vicinity of TC local moment ferromagnets show a very sharp, narrow peak in χ which is suppressed in amplitude and shifted to higher temperatures as the static bias field is increased. Unexpectedly, critical scaling analysis fails for these data. It is seen that these data are frequency dependent, however there is no simple method whereby measurement frequency can be changed in a controllable fashion. In contrast, itinerant ferromagnets show a broad maximum in χ well below TC which is suppressed and shifts to lower temperatures as the dc bias field is increased. The data on itinerant ferromagnets is fitted to a semi-phenomenological model that suggests the sample response is dominated by the uncompensated minority spins in the conduction band. Concluding remarks suggest possible scenarios to achieve frequency resolved data using the TDR as well as other fields in which the apparatus may be exploited.

  13. Dynamic magnetic susceptibility of systems with long-range magnetic order

    NASA Astrophysics Data System (ADS)

    Vannette, Matthew Dano

    The utility of the TDR as an instrument in the study of magnetically ordered materials has been expanded beyond the simple demonstration purposes. Results of static applied magnetic field dependent measurements of the dynamic magnetic susceptibility, chi, of various ferromagnetic (FM) and antiferromagnetic (AFM) materials showing a range of transition temperatures (1-800 K) are presented. Data was collected primarily with a tunnel diode resonator (TDR) at different radio-frequencies (~10-30 MHz). In the vicinity of TC local moment ferromagnets show a very sharp, narrow peak in chi which is suppressed in amplitude and shifted to higher temperatures as the static bias field is increased. Unexpectedly, critical scaling analysis fails for these data. It is seen that these data are frequency dependent, however there is no simple method whereby measurement frequency can be changed in a controllable fashion. In contrast, itinerant ferromagnets show a broad maximum in chi well below TC which is suppressed and shifts to lower temperatures as the dc bias field is increased. The data on itinerant ferromagnets is fitted to a semi-phenomenological model that suggests the sample response is dominated by the uncompensated minority spins in the conduction band. Concluding remarks suggest possible scenarios to achieve frequency resolved data using the TDR as well as other fields in which the apparatus may be exploited.

  14. 3D and 4D magnetic susceptibility tomography based on complex MR images

    DOEpatents

    Chen, Zikuan; Calhoun, Vince D

    2014-11-11

    Magnetic susceptibility is the physical property for T2*-weighted magnetic resonance imaging (T2*MRI). The invention relates to methods for reconstructing an internal distribution (3D map) of magnetic susceptibility values, .chi. (x,y,z), of an object, from 3D T2*MRI phase images, by using Computed Inverse Magnetic Resonance Imaging (CIMRI) tomography. The CIMRI technique solves the inverse problem of the 3D convolution by executing a 3D Total Variation (TV) regularized iterative convolution scheme, using a split Bregman iteration algorithm. The reconstruction of .chi. (x,y,z) can be designed for low-pass, band-pass, and high-pass features by using a convolution kernel that is modified from the standard dipole kernel. Multiple reconstructions can be implemented in parallel, and averaging the reconstructions can suppress noise. 4D dynamic magnetic susceptibility tomography can be implemented by reconstructing a 3D susceptibility volume from a 3D phase volume by performing 3D CIMRI magnetic susceptibility tomography at each snapshot time.

  15. Magnetic susceptibility measurement of solid oxygen at pressures up to 3.3 GPa

    NASA Astrophysics Data System (ADS)

    Mito, M.; Yamaguchi, S.; Tsuruda, H.; Deguchi, H.; Ishizuka, M.

    2014-01-01

    The magnetic susceptibility of solid oxygen had long been observed only in the restricted pressure region below 0.8 GPa. We succeeded in extending the pressure region up to 3.3 GPa by clamping condensed oxygen in the sample chamber of a miniature diamond anvil cell and measuring the dc magnetic susceptibility using a superconducting quantum interference device magnetometer. In this experiment, the well-known α-β and β-γ transitions are observed in the phase diagram, suggesting consistency with the previous results of X-ray and Raman studies. In addition, a new magnetic anomaly is observed in the β phase.

  16. Magnetic susceptibility measurement of solid oxygen at pressures up to 3.3 GPa

    SciTech Connect

    Mito, M. Yamaguchi, S.; Tsuruda, H.; Deguchi, H.; Ishizuka, M.

    2014-01-07

    The magnetic susceptibility of solid oxygen had long been observed only in the restricted pressure region below 0.8 GPa. We succeeded in extending the pressure region up to 3.3 GPa by clamping condensed oxygen in the sample chamber of a miniature diamond anvil cell and measuring the dc magnetic susceptibility using a superconducting quantum interference device magnetometer. In this experiment, the well-known α–β and β–γ transitions are observed in the phase diagram, suggesting consistency with the previous results of X-ray and Raman studies. In addition, a new magnetic anomaly is observed in the β phase.

  17. Heterogeneous anisotropic magnetic susceptibility of the myelin-water layers causes local magnetic field perturbations in axons.

    PubMed

    Puwal, Steffan; Roth, Bradley J; Basser, Peter J

    2017-04-01

    One goal of MRI is to determine the myelin water fraction in neural tissue. One approach is to measure the reduction in T2 * arising from microscopic perturbations in the magnetic field caused by heterogeneities in the magnetic susceptibility of myelin. In this paper, analytic expressions for the induced magnetic field distribution are derived within and around an axon, assuming that the myelin susceptibility is anisotropic. Previous models considered the susceptibility to be piecewise continuous, whereas this model considers a sinusoidally varying susceptibility. Many conclusions are common in both models. When the magnetic field is applied perpendicular to the axon, the magnetic field in the intraaxonal space is uniformly perturbed, the magnetic field in the myelin sheath oscillates between the lipid and water layers, and the magnetic field in the extracellular space just outside the myelin sheath is heterogeneous. These field heterogeneities cause the spins to dephase, shortening T2 *. When the magnetic field is applied along the axon, the field is homogeneous within water-filled regions, including between lipid layers. Therefore the spins do not dephase and the magnetic susceptibility has no effect on T2 *. Generally, the response of an axon is given as the superposition of these two contributions. The sinusoidal model uses a different set of approximations compared with the piecewise model, so their common predictions indicate that the models are not too sensitive to the details of the myelin-water distribution. Other predictions, such as the sensitivity to water diffusion between myelin and water layers, may highlight differences between the two approaches. Copyright © 2016 John Wiley & Sons, Ltd.

  18. Quartz helix magnetic susceptibility balance using the Curie-Cheneveau principle

    USGS Publications Warehouse

    Senftle, F.E.; Lee, M.D.; Monkewicz, A.A.; Mayo, J.W.; Pankey, T.

    1958-01-01

    A quartz spring balance is described which can be used to measure the magnetic susceptibility of submilligram amounts of sample. The magnetic field is supplied by a moving permanent magnet, and the susceptibility is determined by the deflection of the spring observed in a measuring microscope. The apparatus is calibrated by a comparison standard (platinum) and results are shown for platinum, nickel aluminate, lead, manganese, and sucrose. A precision of better than 2% can be obtained on submilligram amounts of paramagnetic substances having a magnetic susceptibility of from 1 to 50??10-6 emu/g. On weakly paramagnetic or diamagnetic substances comparable precision can be obtained on less than 10 mg amounts of sample. ?? 1958 The American Institute of Physics.

  19. Quantification of magnetic nanoparticles with broadband measurements of magnetic susceptibility in the frequency domain

    NASA Astrophysics Data System (ADS)

    Kodama, Kazuto; An, Zhisheng; Chang, Hong; Qiang, Xiaoke

    2015-04-01

    Measurement of low-field magnetic susceptibility over a wide band of frequencies spanning four orders of magnitude is a useful method for the assessment of the grain size distribution of ultrafine magnetic particles smaller than the SP/SSD boundary. This method has been applied to a loess/paleosol sequence at Luochuan in the Chinese Loess Plateau. The studied succession consists of sequences from the latest paleosol unit to the upper part of the loess unit, spanning the last glacial-interglacial cycle. Reconstructed grain size distributions (GSDs) consist of volume fractions on the order of 10-24 m3, and the mean GSDs are modal but with distinctive skewness among the loess, the weakly developed paleosol (weak paleosol), and the mature paleosol. This indicates that the mean volume of SP particles in this sequence tends to increase during the transition from the loess to the paleosol. An index, defined as the difference between χ130 at the lowest (130 Hz) and χ500k at the highest (500 kHz) frequencies normalized to χ130, is judged to be a more suitable index than previous frequency dependence parameters for the concentration of SP particles. This index has a strong correlation with χ130, showing a continuous 'growth curve' with the rate of increase being highest for the loess, moderate for the weak paleosol, and saturated for the paleosol. The characteristic curve suggests that smaller SP particles are preferentially formed in the earlier stage of pedogenesis rather than the later phase when even larger particles are formed in the mature paleosol. These results demonstrate that the broad-band-frequency susceptibility measurement will be useful for the quantitative assessment of magnetic nanoparticles in soils and sediments. Additionally, we point out that the measurement in the frequency domain generally requires time and may not be most suitable to routine measurements. We thus propose an alternative manner, the measurement in the time domain that can be

  20. Calculation of susceptibility through multiple orientation sampling (COSMOS): a method for conditioning the inverse problem from measured magnetic field map to susceptibility source image in MRI.

    PubMed

    Liu, Tian; Spincemaille, Pascal; de Rochefort, Ludovic; Kressler, Bryan; Wang, Yi

    2009-01-01

    Magnetic susceptibility differs among tissues based on their contents of iron, calcium, contrast agent, and other molecular compositions. Susceptibility modifies the magnetic field detected in the MR signal phase. The determination of an arbitrary susceptibility distribution from the induced field shifts is a challenging, ill-posed inverse problem. A method called "calculation of susceptibility through multiple orientation sampling" (COSMOS) is proposed to stabilize this inverse problem. The field created by the susceptibility distribution is sampled at multiple orientations with respect to the polarization field, B(0), and the susceptibility map is reconstructed by weighted linear least squares to account for field noise and the signal void region. Numerical simulations and phantom and in vitro imaging validations demonstrated that COSMOS is a stable and precise approach to quantify a susceptibility distribution using MRI.

  1. Probe imaging studies of magnetic susceptibility and permeability for sensitive characterisation of carbonate reservoir rocks

    NASA Astrophysics Data System (ADS)

    Ivakhnenko, Aleksandr; Bigaliyeva, Akmaral; Dubinin, Vladislav

    2016-04-01

    In this study were disclosed the main principals of identifying petrophysical properties of carbonate reservoirs such as porosity, permeability and magnetic susceptibility. While exploring and developing reservoir there are significant diversity of tasks that can be solved by appropriate knowledge of properties which are listed above. Behavior of fluid flow, distribution of hydrocarbons and other various industrial applications can be solved by measuring areal distribution of these petrophysical parameters. The results demonstrate how magnetic probe and hysteresis measurements correlate with petrophysical parameters in carbonate reservoirs. We made experimental measurements and theoretical calculations of how much magnetic susceptibility depends on the porosity of the rocks and analyzed data with graphics. In theoretical model of the carbonate rocks we considered calcite, dolomite, quartz and combinations of calcite and dolomite, calcite and Fe-dolomite, calcite and quartz, calcite and aragonite with increasing concentrations of the dolomite, Fe-dolomite, quartz and aragonite up to 50% with step of 5%. Here we defined dependence of magnetic susceptibility from the porosity: the higher porosity measurements, the less slope of magnetic susceptibility, consequently mass magnetization is higher for diamagnetic and lower for paramagnetic carbonate rocks, but in the both cases magnetic susceptibility tries to reach zero with increasing of the total porosity. Rock measurements demonstrate that reservoir zones of the low diamagnetic magnetic susceptibility are generally correlated with higher permeability and also porosity distribution. However for different carbonate reservoirs we establish different relationships depending on the complexity of their mineralogy and texture. Application of integral understanding in distribution of permeability, porosity and mineral content in heterogeneous carbonates represented by this approach can be useful tool for carbonate reservoir

  2. Homogeneous magnetic susceptibilities of tektites: Implications for extreme homogenization of source material

    NASA Astrophysics Data System (ADS)

    Werner, Tomasz; Borradaile, Graham John

    Low field magnetic susceptibility of 151 tektites from the Australasian strewn field is dominated by paramagnetism of the silicate glass. Ferromagnetic contributions are negligible because the formation of oxides was suppressed during rapid quenching. A few samples from the Central European strewn field show similar properties. Also, susceptibilities calculated from the large number of published geochemical analyses yield similar low susceptibilities. To produce low mass susceptibilities in such a narrow range of 50-100×10 -9 m 3 kg -1, paramagnetic behaviour and negligible remanence, a target source that is both appropriate and widespread over the Earth's surface is required. Modern marine sediments would appear to fill these requirements. The uniformity of the material, and hence its magnetic properties would be enhanced by the thorough mixing of molten terrestrial sedimentary during vaporization and ejection and its subsequent rapid quenching.

  3. Magnetic susceptibility of Inconel alloys 718, 625, and 600 at cryogenic temperatures

    NASA Technical Reports Server (NTRS)

    Goldberg, Ira B.; Mitchell, Michael R.; Murphy, Allan R.; Goldfarb, Ronald B.; Loughran, Robert J.

    1990-01-01

    After a hydrogen fuel bleed valve problem on the Discovery Space Shuttle was traced to the strong magnetization of Inconel 718 in the armature of the linear variable differential transformer near liquid hydrogen temperatures, the ac magnetic susceptibility of three samples of Inconel 718 of slightly different compositions, one sample of Inconel 625, and on sample of Inconel 600 were measured as a function of temperature. Inconel 718 alloys are found to exhibit a spin glass state below 16 K. Inconel 600 exhibits three different magnetic phases, the lowest-temperature state (below 6 K) being somewhat similar to that of Inconel 718. The magnetic states of the Inconel alloys and their magnetic susceptibilities appear to be strongly dependent on the exact composition of the alloy.

  4. Quantitative susceptibility mapping (QSM): Decoding MRI data for a tissue magnetic biomarker

    PubMed Central

    Wang, Yi; Liu, Tian

    2015-01-01

    In MRI, the main magnetic field polarizes the electron cloud of a molecule, generating a chemical shift for observer protons within the molecule and a magnetic susceptibility inhomogeneity field for observer protons outside the molecule. The number of water protons surrounding a molecule for detecting its magnetic susceptibility is vastly greater than the number of protons within the molecule for detecting its chemical shift. However, the study of tissue magnetic susceptibility has been hindered by poor molecular specificities of hitherto used methods based on MRI signal phase and T2* contrast, which depend convolutedly on surrounding susceptibility sources. Deconvolution of the MRI signal phase can determine tissue susceptibility but is challenged by the lack of MRI signal in the background and by the zeroes in the dipole kernel. Recently, physically meaningful regularizations, including the Bayesian approach, have been developed to enable accurate quantitative susceptibility mapping (QSM) for studying iron distribution, metabolic oxygen consumption, blood degradation, calcification, demyelination, and other pathophysiological susceptibility changes, as well as contrast agent biodistribution in MRI. This paper attempts to summarize the basic physical concepts and essential algorithmic steps in QSM, to describe clinical and technical issues under active development, and to provide references, codes, and testing data for readers interested in QSM. Magn Reson Med 73:82–101, 2015. © 2014 The Authors. Magnetic Resonance in Medicine Published by Wiley Periodicals, Inc. on behalf of International Society of Medicine in Resonance. This is an open access article under the terms of the Creative commons Attribution License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited. PMID:25044035

  5. Design of Low Temperature AC Susceptibility Measurement Scheme for Molecular Magnets

    NASA Astrophysics Data System (ADS)

    Korenblit, Simcha; Moon, Byoung; Lee, Yoonseok; Sultan, Reza

    2006-03-01

    AC susceptibility is one of the most important physical properties in many materials such as magnetic materials and superconductors. Although there are many commercial AC susceptibility measurement systems which cover a broad range of temperatures, it is still a daunting task to extend their measurement range into the low millikelvins. We are currently developing a low temperature AC susceptometer for the mK range. As a part of this effort, we have developed a versatile low-cost computer controlled coil-winder to make various types of coils. We have designed primary and secondary coils and wound them using the machine, and performed characterization of the AC susceptometer. In this presentation, I will explain the basics of magnetic susceptibility, its measurement, design considerations for building an AC magnetic susceptometer, and discuss the details of an actual apparatus designed and realized by the authors.

  6. Effect of copper addition on density and magnetic susceptibility of lithium borate glasses

    NASA Astrophysics Data System (ADS)

    Kashif, I.; Soliman, A. A.; Farouk, H.; El-Shorpagy, M.; Sanad, A. M.

    2008-11-01

    Glasses of the (100- x) (Li 2O·2B 2O 3)· x CuO system, where x=0, 5, 10, 15, 20, 25 mol%, were prepared by melt quench technique. The glass samples were studied by magnetic susceptibility, density and infrared (IR) spectroscopic measurements. Molar volumes were estimated from density data. IR spectroscopic and density data show that the copper ions play a network modifier role and some ions as a network former by increasing the copper content in the studied glasses. The magnetic susceptibility data show a variable behavior due to the presence of two types of copper ions, cuprous (Cu +) and cupric (Cu 2+), in all samples.

  7. Sub-micron mapping of GHz magnetic susceptibility using scanning transmission x-ray microscopy

    NASA Astrophysics Data System (ADS)

    Cheng, Cheng; Bailey, William E.

    2012-10-01

    We report submicron imaging (˜0.75 μm resolution) of complex magnetic susceptibility in a micron-size ferromagnetic heterostructure using time-resolved scanning transmission x-ray microscopy. The real and imaginary parts of the susceptibility are extracted from the phase and amplitude of the small-angle (<20°) rotational response of the local magnetization under microwave excitation. Frequency-dependent response patterns were observed in an incompletely saturated bilayer element. The technique is extensible to higher frequencies (to ˜10 GHz), better spatial resolution, and layer-specific measurement.

  8. Comparison between theory and simulations for the magnetization and the susceptibility of polydisperse ferrofluids.

    PubMed

    Szalai, I; Nagy, S; Dietrich, S

    2013-11-20

    The influence of polydispersity on the magnetization of ferrofluids is studied based on a previously published magnetization equation of state (Szalai and Dietrich, 2011 J. Phys.: Condens. Matter 23 326004) and computer simulations. The polydispersity of the particle diameter is described by the gamma distribution function. Canonical ensemble Monte Carlo simulations have been performed in order to test these theoretical results for the initial susceptibility and the magnetization. The results for the magnetic properties of the polydisperse systems turn out to be in quantitative agreement with our present simulation data. In addition, we find good agreement between our theory and experimental data for magnetite-based ferrofluids.

  9. Quantification of cellular properties from external fields and resulting induced velocity: magnetic susceptibility.

    PubMed

    Chalmers, J J; Haam, S; Zhao, Y; McCloskey, K; Moore, L; Zborowski, M; Williams, P S

    1999-09-05

    An experimental technique is discussed in which the magnetic susceptibility of immunomagnetically labeled cells can be determined on a cell-by-cell basis. This technique is based on determining the magnetically induced velocity that an immunomagnetically labeled cell has in a well-defined magnetic energy gradient. This velocity is determined through the use of video recordings of microscopic images of cells moving in the magnetic energy gradient. These video images are then computer digitized and processed using a computer algorithm, cell tracking velocimetry, which allows larger numbers (>10(3)) of cells to be analyzed.

  10. Effects of Size, deGennes and Ginzburg-Landau Parameters on the Magnetic Susceptibility of an Isotropic Superconductor

    NASA Astrophysics Data System (ADS)

    Aguirre, C. A.; González, J. D.; Barba-Ortega, J.

    2016-01-01

    The magnetic signature of a nanoscopic superconductor immersed in a magnetic applied field H_e is calculated numerically. The calculated magnetic susceptibility partial M / partial H_e of a superconducting nanoprism shows discontinuities and a quasiperiodic modulation at the vortex transition fields H_T (fields for which one or several vortices enter/leave the sample). In this contribution, we studied the influence of the sample size, the Ginzburg-Landau parameter κ and the deGennes parameter b on the magnetic susceptibility in a type-II isotropic superconductor. We found distinct signatures of the magnetic susceptibility when superconducting samples of two and three dimensions are considered.

  11. Observation of a Strongly Enhanced Magnetic Susceptibility of Pd in Au-Pd-Au Sandwiches

    NASA Astrophysics Data System (ADS)

    Brodsky, M. B.; Freeman, A. J.

    1980-07-01

    Exceptionally large increases in the magnetic susceptibility (indicating nearly magnetic ordering) of thin films of Pd sandwiched between thicker Au films have been observed at low temperatures-presumably due to the expansion of the Pd average lattice constant by the Au. The large resultant Stoner factors and the modified paramagnon model of Levin and Valls indicate the possibility of observing p-wave superconductivity in Pd structures with reduced proximity effects.

  12. Magnetic susceptibility study of the heavy rare-earth stannate pyrochlores

    NASA Astrophysics Data System (ADS)

    Bondah-Jagalu, V.; Bramwell, S. T.

    2001-11-01

    The series of magnetic rare earth pyrochlore stannates R2Sn2O7 (R = rare earth, except Ce and Pm) have been investigated by powder susceptibility measurements down to T =1.8 K. The results are compared to results for the analogous titanate series, which are well-known frustrated magnets. Unlike the titanates, the whole series can be formed in the cubic pyrochlore structure. Possible experimental advantages of studying the stannates are discussed.

  13. Multifractal magnetic susceptibility distribution models of hydrothermally altered rocks in the Needle Creek Igneous Center of the Absaroka Mountains, Wyoming

    USGS Publications Warehouse

    Gettings, M.E.

    2005-01-01

    Magnetic susceptibility was measured for 700 samples of drill core from thirteen drill holes in the porphyry copper-molybdenum deposit of the Stinkingwater mining district in the Absaroka Mountains, Wyoming. The magnetic susceptibility measurements, chemical analyses, and alteration class provided a database for study of magnetic susceptibility in these altered rocks. The distribution of the magnetic susceptibilities for all samples is multi-modal, with overlapping peaked distributions for samples in the propylitic and phyllic alteration class, a tail of higher susceptibilities for potassic alteration, and an approximately uniform distribution over a narrow range at the highest susceptibilities for unaltered rocks. Samples from all alteration and mineralization classes show susceptibilities across a wide range of values. Samples with secondary (supergene) alteration due to oxidation or enrichment show lower susceptibilities than primary (hypogene) alteration rock. Observed magnetic susceptibility variations and the monolithological character of the host rock suggest that the variations are due to varying degrees of alteration of blocks of rock between fractures that conducted hydrothermal fluids. Alteration of rock from the fractures inward progressively reduces the bulk magnetic susceptibility of the rock. The model introduced in this paper consists of a simulation of the fracture pattern and a simulation of the alteration of the rock between fractures. A multifractal model generated from multiplicative cascades with unequal ratios produces distributions statistically similar to the observed distributions. The reduction in susceptibility in the altered rocks was modelled as a diffusion process operating on the fracture distribution support. The average magnetic susceptibility was then computed for each block. For the purpose of comparing the model results with observation, the simulated magnetic susceptibilities were then averaged over the same interval as the

  14. A Torque Balance Measurement of Anisotropy of the Magnetic Susceptibility in White Matter

    PubMed Central

    van Gelderen, Peter; Mandelkow, Hendrik; de Zwart, Jacco A.; Duyn, Jeff H.

    2014-01-01

    Purpose Recent MRI studies have suggested that the magnetic susceptibility of white matter (WM) in the human brain is anisotropic, providing a new contrast mechanism for the visualization of fiber bundles and allowing the extraction of cellular compartment-specific information. This study provides an independent confirmation and quantification of this anisotropy. Methods Anisotropic magnetic susceptibility results in a torque exerted on WM when placed in a uniform magnetic field, tending to align the WM fibers with the field. To quantify the effect, excised spinal cord samples were placed in a torque balance inside the magnet of a 7 T MRI system and the magnetic torque was measured as function of orientation. Results All tissue samples (n=5) showed orienting effects, confirming the presence of anisotropic susceptibility. Analysis of the magnetic torque resulted in reproducible values for the WM volume anisotropy that ranged from 13.6 to 19.2 ppb. Conclusion The independently determined anisotropy values confirm estimates inferred from MRI experiments and validate the use of anisotropy to extract novel information about brain fiber structure and myelination. PMID:25399830

  15. Obtaining the magnetic susceptibility of the heme complex from DFT calculations

    NASA Astrophysics Data System (ADS)

    Pereira, L. M. O.; Resende, S. M.; Leite Alves, H. W.

    2016-09-01

    Magnetic field interactions with particles, as observed in magnetophoresis, are becoming important tool to understand the nature of the iron role in heme molecular complex, besides other useful applications. Accurate estimations of some macroscopic magnetic properties from quantum mechanical calculations, such as the magnetic susceptibility, can also check the reliability of the heme microscopic models. In this work we report, by using the Stoner criterion, a simple way to obtain the magnetic susceptibility of the heme complex from Density Functional Theory calculations. Some of our calculated structural properties and electronic structure show good agreement with both the available experimental and theoretical data, and the results show that its groundstate is a triplet 3A state. From the obtained results, we have evaluated the exchange interaction energy, J = 0.98 eV, the associated magnetic energy gain, Δ EM =-0.68 eV, and the magnetic susceptibility, χ0=1.73 ×10-6 cm3/mol for the heme alone (with uncompleted Fe ligands). If we consider the heme complex with the two histidine residues (completing the Fe ligands), we have then obtained χ0=5.27 ×10-12 cm3/g, which is in good agreement with experimental magnetophoresis data.

  16. 3D linear inversion of magnetic susceptibility data acquired by frequency domain EMI

    NASA Astrophysics Data System (ADS)

    Thiesson, J.; Tabbagh, A.; Simon, F.-X.; Dabas, M.

    2017-01-01

    Low induction number EMI instruments are able to simultaneously measure a soil's apparent magnetic susceptibility and electrical conductivity. This family of dual measurement instruments is highly useful for the analysis of soils and archeological sites. However, the electromagnetic properties of soils are found to vary over considerably different ranges: whereas their electrical conductivity varies from ≤ 0.1 to ≥ 100 mS/m, their relative magnetic permeability remains within a very small range, between 1.0001 and 1.01 SI. Consequently, although apparent conductivity measurements need to be inverted using non-linear processes, the variations of the apparent magnetic susceptibility can be approximated through the use of linear processes, as in the case of the magnetic prospection technique. Our proposed 3D inversion algorithm starts from apparent susceptibility data sets, acquired using different instruments over a given area. A reference vertical profile is defined by considering the mode of the vertical distributions of both the electrical resistivity and of the magnetic susceptibility. At each point of the mapped area, the reference vertical profile response is subtracted to obtain the apparent susceptibility variation dataset. A 2D horizontal Fourier transform is applied to these variation datasets and to the dipole (impulse) response of each instrument, a (vertical) 1D inversion is performed at each point in the spectral domain, and finally the resulting dataset is inverse transformed to restore the apparent 3D susceptibility variations. It has been shown that when applied to synthetic results, this method is able to correct the apparent deformations of a buried object resulting from the geometry of the instrument, and to restore reliable quantitative susceptibility contrasts. It also allows the thin layer solution, similar to that used in magnetic prospection, to be implemented. When applied to field data it initially delivers a level of contrast

  17. Analysis of the susceptibility of condensed oxygen under high pressures and in strong magnetic fields

    NASA Astrophysics Data System (ADS)

    Kilit Doğan, E.; Yurtseven, H.

    2017-03-01

    The temperature dependence of the magnetic susceptibility is analyzed at some constant pressures by a power-law formula using the experimental data from the literature for the α - β and β - γ transitions in oxygen. A weak discontinuous (nearly continuous) transition occurring from the α to the β phase, becomes more discontinuous (weakly first order) for the β - γ transition as observed experimentally, which can be explained in terms of the critical exponents deduced from our analysis. The magnetic field dependence of the differential susceptibility is also analyzed in this study for the α -O2 at 4.2 K by a power-law formula using the experimental data. λ-type of observed behaviour of the differential susceptibility is discussed in terms of our analysis for the α -O2 .

  18. Anisotropic magnetic susceptibility of erbium and ytterbium in zircon, ZrSiO4

    USGS Publications Warehouse

    Thorpe, A.N.; Briggs, Charles; Tsang, T.; Senftle, F.; Alexander, Corrine

    1977-01-01

    Magnetic susceptibility measurements have been made for both Er- and Yb-doped (1̃03ppm) zircon single crystals with the magnetic field perpendicular and parallel to the [001] axis. Large susceptibility anisotropies were found in both cases. Our observed anisotropies of ZrSiO4: Yb indicate small populations (1̃9%) of Yb ions at the axial (tetragonal) sites, as the susceptibility of ZrSiO4: Yb would be nearly isotropic if the Yb ions only occupied the orthorhombic sites. For Er3+ in orthorhombic sites of zircon, our data indicate that the first excited state is paramagnetic with gx = 9 and gy 5̃ at 20 cm-1 above the ground state (gx 0̃, gy 1̃5). The first excited state is quite similar to the ground states observed for Er3+ in many host lattices. ?? 1977.

  19. Single crystal magnetic structure and susceptibility of CoSe2O5

    DOE PAGES

    Rodriguez, Efrain E.; Cao, Huibo; Haiges, Ralf; ...

    2015-09-08

    The structure of CoSe2O5 consists of one-dimensional ribbons of edge-sharing CoO6 octahedra bound together by polyanionic subunits of Se2O5. Previous work on polycrystalline samples reported a canted antiferromagnetic arrangement of the magnetic moments below the ordering temperature of 8.5 K. Here, we report a single crystal investigation using variable temperature and field magnetic susceptibility and low-temperature neutron diffraction to more precisely characterize the nature of the magnetic ground state of CoSe2O5. Contrary to previous reports, we find that the single crystal magnetic structure shows no canting of the antiferromagnetic ground state, and in the process have identified several field-induced changesmore » to the magnetization. Lastly, we discuss these results in the context of the revised magnetic structure and highlight the importance of crystal growth for the accurate characterization of these properties.« less

  20. Magnetic Susceptibility as a Proxy for Investigating Microbial Mediated Iron Reduction

    EPA Science Inventory

    We investigated magnetic susceptibility (MS) variations in hydrocarbon contaminated sediments. Our objective was to determine if MS can be used as an intrinsic bioremediation indicator due to the activity of iron-reducing bacteria. A contaminated and an uncontaminated core were r...

  1. Improvement of immunoassay detection system by using alternating current magnetic susceptibility.

    PubMed

    Kawabata, R; Mizoguchi, T; Kandori, A

    2016-03-01

    A major goal with this research was to develop a low-cost and highly sensitive immunoassay detection system by using alternating current (AC) magnetic susceptibility. We fabricated an improved prototype of our previously developed immunoassay detection system and evaluated its performance. The prototype continuously moved sample containers by using a magnetically shielded brushless motor, which passes between two anisotropic magneto resistance (AMR) sensors. These sensors detected the magnetic signal in the direction where each sample container passed them. We used the differential signal obtained from each AMR sensor's output to improve the signal-to-noise ratio (SNR) of the magnetic signal measurement. Biotin-conjugated polymer beads with avidin-coated magnetic particles were prepared to examine the calibration curve, which represents the relation between AC magnetic susceptibility change and polymer-bead concentration. For the calibration curve measurement, we, respectively, measured the magnetic signal caused by the magnetic particles by using each AMR sensor installed near the upper or lower part in the lateral position of the passing sample containers. As a result, the SNR of the prototype was 4.5 times better than that of our previous system. Moreover, the data obtained from each AMR sensor installed near the upper part in the lateral position of the passing sample containers exhibited an accurate calibration curve that represented good correlation between AC magnetic susceptibility change and polymer-bead concentration. The conclusion drawn from these findings is that our improved immunoassay detection system will enable a low-cost and highly sensitive immunoassay.

  2. Improvement of immunoassay detection system by using alternating current magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Kawabata, R.; Mizoguchi, T.; Kandori, A.

    2016-03-01

    A major goal with this research was to develop a low-cost and highly sensitive immunoassay detection system by using alternating current (AC) magnetic susceptibility. We fabricated an improved prototype of our previously developed immunoassay detection system and evaluated its performance. The prototype continuously moved sample containers by using a magnetically shielded brushless motor, which passes between two anisotropic magneto resistance (AMR) sensors. These sensors detected the magnetic signal in the direction where each sample container passed them. We used the differential signal obtained from each AMR sensor's output to improve the signal-to-noise ratio (SNR) of the magnetic signal measurement. Biotin-conjugated polymer beads with avidin-coated magnetic particles were prepared to examine the calibration curve, which represents the relation between AC magnetic susceptibility change and polymer-bead concentration. For the calibration curve measurement, we, respectively, measured the magnetic signal caused by the magnetic particles by using each AMR sensor installed near the upper or lower part in the lateral position of the passing sample containers. As a result, the SNR of the prototype was 4.5 times better than that of our previous system. Moreover, the data obtained from each AMR sensor installed near the upper part in the lateral position of the passing sample containers exhibited an accurate calibration curve that represented good correlation between AC magnetic susceptibility change and polymer-bead concentration. The conclusion drawn from these findings is that our improved immunoassay detection system will enable a low-cost and highly sensitive immunoassay.

  3. Estimating the contribution of Brownian and Néel relaxation in a magnetic fluid through dynamic magnetic susceptibility measurements

    NASA Astrophysics Data System (ADS)

    Maldonado-Camargo, L.; Torres-Díaz, I.; Chiu-Lam, A.; Hernández, M.; Rinaldi, C.

    2016-08-01

    We demonstrate how dynamic magnetic susceptibility measurements (DMS) can be used to estimate the relative contributions of Brownian and Néel relaxation to the dynamic magnetic response of a magnetic fluid, a suspension of magnetic nanoparticles. The method applies to suspensions with particles that respond through Brownian or Néel relaxation and for which the characteristic Brownian and Néel relaxation times are widely separated. First, we illustrate this using magnetic fluids consisting of mixtures of particles that relax solely by the Brownian or Néel mechanisms. Then, it is shown how the same approach can be applied to estimate the relative contributions of Brownian and Néel relaxation in a suspension consisting of particles obtained from a single synthesis and whose size distribution straddles the transition from Néel to Brownian relaxation.

  4. Magnetoresistance, susceptibility and magnetization measurements on RNiBC compounds (R = Er, Ho, Dy, Tb, and Gd)

    NASA Astrophysics Data System (ADS)

    Tróchez, J. C.; Sánchez, D. R.; Giordanengo, B.; Fontes, M. B.; Continentino, Múcio; Baggio-Saitovitch, E. M.

    1997-08-01

    We studied magnetic behavior of the RNiBC compounds by magnetic and transport measurements. At low temperatures, each compound has different magnetic structure. Magnetoresistivity data are in good accordance with theory of magnetic elementary interactions, susceptibility reveals the magnetic transition and Curie Weiss behavior and magnetization shows low value of the saturation compared with the free R+3 ion that confirm that crystalline electric field is strong as in the RNi2B2C series.

  5. Impact of grass cover on the magnetic susceptibility measurements for assessing metal contamination in urban topsoil.

    PubMed

    Golden, Nessa; Zhang, Chaosheng; Potito, Aaron P; Gibson, Paul J; Bargary, Norma; Morrison, Liam

    2017-03-02

    In recent decades, magnetic susceptibility monitoring has developed as a useful technique in environmental pollution studies, particularly metal contamination of soil. This study provides the first ever examination of the effects of grass cover on magnetic susceptibility (MS) measurements of underlying urban soils. Magnetic measurements were taken in situ to determine the effects on κ (volume magnetic susceptibility) when the grass layer was present (κ(grass)) and after the grass layer was trimmed down to the root (κ(no grass)). Height of grass was recorded in situ at each grid point. Soil samples (n=185) were collected and measurements of mass specific magnetic susceptibility (χ) were performed in the laboratory and frequency dependence (χfd%) calculated. Metal concentrations (Pb, Cu, Zn and Fe) in the soil samples were determined and a gradiometry survey carried out in situ on a section of the study area. Significant correlations were found between each of the MS measurements and the metal content of the soil at the p<0.01 level. Spatial distribution maps were created using Inverse Distance Weighting (IDW) and Local Indicators of Spatial Association (LISA) to identify common patterns. κ(grass) (ranged from 1.67 to 301.00×10(-5) SI) and κ(no grass) (ranged from 2.08 to 530.67×10(-5) SI) measured in situ are highly correlated [r=0.966, n=194, p<0.01]. The volume susceptibility datasets in the presence and absence of grass coverage share a similar spatial distribution pattern. This study re-evaluates in situ κ monitoring techniques and the results suggest that the removal of grass coverage prior to obtaining in situ κ measurements of urban soil is unnecessary. This layer does not impede the MS sensor from accurately measuring elevated κ in soils, and therefore κ measurements recorded with grass coverage present can be reliably used to identify areas of urban soil metal contamination.

  6. Global Lithospheric Apparent Susceptibility Distribution Converted from Geomagnetic Models by CHAMP and Swarm Satellite Magnetic Measurements

    NASA Astrophysics Data System (ADS)

    Du, Jinsong; Chen, Chao; Xiong, Xiong; Li, Yongdong; Liang, Qing

    2016-04-01

    Recently, because of continually accumulated magnetic measurements by CHAMP satellite and Swarm constellation of three satellites and well developed methodologies and techniques of data processing and geomagnetic field modeling etc., global lithospheric magnetic anomaly field models become more and more reliable. This makes the quantitative interpretation of lithospheric magnetic anomaly field possible for having an insight into large-scale magnetic structures in the crust and uppermost mantle. Many different approaches have been utilized to understand the magnetized sources, such as forward, inversion, statistics, correlation analysis, Euler deconvolution, signal transformations etc. Among all quantitative interpretation methods, the directly converting a magnetic anomaly map into a magnetic susceptibility anomaly map proposed by Arkani-Hamed & Strangway (1985) is, we think, the most fast quantitative interpretation tool for global studies. We just call this method AS85 hereinafter for short. Although Gubbins et al. (2011) provided a formula to directly calculate the apparent magnetic vector distribution, the AS85 method introduced constraints of magnetized direction and thus corresponding results are expected to be more robust especially in world-wide continents. Therefore, in this study, we first improved the AS85 method further considering non-axial dipolar inducing field using formulae by Nolte & Siebert (1987), initial model or priori information for starting coefficients in the apparent susceptibility conversion, hidden longest-wavelength components of lithospheric magnetic field and field contaminations from global oceanic remanent magnetization. Then, we used the vertically integrated susceptibility model by Hemant & Maus (2005) and vertically integrated remanent magnetization model by Masterton et al. (2013) to test the validity of our improved method. Subsequently, we applied the conversion method to geomagnetic field models by CHAMP and Swarm satellite

  7. Can the magnetic susceptibility record of Chinese Red Clay sequence be used for palaeomonsoon reconstructions?

    NASA Astrophysics Data System (ADS)

    Zhao, Guoyong; Han, Yan; Liu, Xiuming; Chang, Liao; Lü, Bin; Chen, Qu; Guo, Xuelian; Yan, Junhui; Yan, Jun

    2016-03-01

    Red Clay underlying the loess-palaeosol sequences on the Chinese Loess Plateau is an eolian deposit. There is a controversy over whether magnetic susceptibility (χ) variations in Red Clay sequence can be used as an indicator of summer palaeomonsoon intensity. This study investigates the magnetic mineralogy, magnetic concentration and magnetic grain size distribution of Jiaxian Red Clay with multimagnetic methods. Our results indicate that the magnetic properties of Jiaxian Red Clay are similar to those of the Quaternary loess-palaeosol sequences, and ultrafine ferrimagnetic grains produced during pedogenesis are responsible for an increase in susceptibility, therefore the χ enhancement mechanism of Red Clay is similar to that of the overlying loess-palaeosol sequences. This paper explores χ variations in the Red Clay sequence through spatial and temporal analysis. The susceptibility variation of six sites along a NNE to SSW transect correlate to palaeoclimatic cycles, so χ can be used to trace the summer palaeomonsoon intensity from a spatial perspective. However, a simple loess-derived calibration function cannot be used to quantitative reconstruct the palaeomonsoon intensity variations thought time. An adjusted calibration function for palaeosols from Red Clay sequence needs to be developed, so that χ can be used to quantitative reconstruct palaeomonsoon intensity. Further study is necessary to develop such a transfer function.

  8. Magnetic susceptibility effects on 13C MAS NMR spectra of carbon materials and graphite.

    PubMed

    Freita, J C; Emmerich, F G; Cernicchiaro, G R; Sampaio, L C; Bonagamba, T J

    2001-01-01

    13C high-resolution solid-state nuclear magnetic resonance (NMR) was employed to study carbon materials prepared through the thermal decomposition of four different organic precursors (rice hulls, endocarp of babassu coconut, peat, and PVC). For heat treatment temperatures (HTTs) above about 600 C, all materials presented 13C NMR spectra composed of a unique resonance line associated with carbon atoms in aromatic planes. With increasing HTT a continuous broadening of this resonance and a diamagnetic shift in its central frequency were verified for all samples. The evolution of the magnitude and anisotropy of the magnetic susceptibility of the heat-treated carbon samples with HTT explains well these findings. It is shown that these results are better understood when a comparison is made with the features of the 13C NMR spectrum of polycrystalline graphite, for which the magnetic susceptibility effect is also present and is much more pronounced.

  9. Magnetization, magnetic susceptibility, effective magnetic moment of Fe{sup 3+} ions in Bi{sub 25}FeO{sub 39} ferrite

    SciTech Connect

    Zatsiupa, A.A.; Bashkirov, L.A.; Troyanchuk, I.O.; Petrov, G.S.; Galyas, A.I.; Lobanovsky, L.S.; Truhanov, S.V.

    2014-04-01

    Magnetic susceptibility for ferrite Bi{sub 25}FeO{sub 39} is measured at 5–950 K in the magnetic field of 0.86 T. It is shown that Bi{sub 25}FeO{sub 39} is paramagnetic in the temperature range 5−950 K. The saturation magnetization is equal to 5.04μ{sub B} per formula unit at 5 K in a magnetic field of 10 T. It is found that at 5−300 K the effective magnetic moment of Fe{sup 3+} ions in Bi{sub 25}FeO{sub 39} is equal to 5.82μ{sub B}. - Graphical abstract: The dependence of the magnetization (n, μ{sub B}) on the magnetic field for one formula unit of Bi{sub 25}FeO{sub 39} at 5 K. - Highlights: • Magnetic susceptibility for Bi{sub 25}FeO{sub 39} is measured at 5–950 K in the magnetic field of 0.86 T. • It is shown that Bi{sub 25}FeO{sub 39} is paramagnetic in the temperature range 5−950 K. • The saturation magnetization is equal to 5.04μ{sub B} per formula unit at 5 K in a magnetic field of 10 T.

  10. Effects of phase constitution on magnetic susceptibility and mechanical properties of Zr-rich Zr-Mo alloys.

    PubMed

    Suyalatu; Kondo, Ryota; Tsutsumi, Yusuke; Doi, Hisashi; Nomura, Naoyuki; Hanawa, Takao

    2011-12-01

    The effects of the microstructures and phases of Zr-rich Mo alloys on their magnetic susceptibilities and mechanical properties were investigated in order to develop a Zr alloy with low magnetic susceptibility for use in magnetic resonance imaging (MRI). The magnetic susceptibility was measured with a magnetic susceptibility balance, while mechanical properties were evaluated by a tensile test. The microstructure was evaluated with an X-ray diffractometer, an optical microscope, and a transmission electron microscope. Evaluation of the microstructures revealed that the α' phase was the dominant form at less than 2% Mo content in the as-cast alloy. The ω phase was formed in as-cast Zr-3Mo but disappeared with aging at 973 K. Magnetic susceptibility was reflected in the phase constitution: the susceptibility showed a local minimum at Zr-(0.5-1)Mo with mostly α' phase and a minimum at Zr-3Mo with mostly β and ω phases. The magnetic susceptibility of as-cast Zr-3Mo increased at 973 K due to disappearance of the ω phase. However, the susceptibility was still as low as that of as-cast Zr-1Mo. The ultimate tensile strength of α'-based Zr-Mo alloys was tailored from 674 to 970 MPa, and the corresponding elongation varied from 11.1% to 2.9%. Because Zr-Mo alloys containing ω phase were found, through tensile tests, to be brittle this phase should be avoided, irrespective of the low magnetic susceptibility, in order to maintain mechanical reliability. Elongation of the Zr-3Mo alloy was dramatically improved when the phase constitution was changed to α and β phases by aging at 973 K for 86.4 ks. The magnetic susceptibilities of the α'-based Zr-Mo alloys are one-third those of Ti-6Al-4V and Ti-6Al-7Nb, and thus these Zr alloys are useful for medical devices under MRI.

  11. Effect of molecule-particle binding on the reduction in the mixed-frequency alternating current magnetic susceptibility of magnetic bio-reagents

    NASA Astrophysics Data System (ADS)

    Yang, C. C.; Yang, S. Y.; Chen, H. H.; Weng, W. L.; Horng, H. E.; Chieh, J. J.; Hong, C. Y.; Yang, H. C.

    2012-07-01

    By specifically bio-functionalizing magnetic nanoparticles, magnetic nanoparticles are able to label target bio-molecules. This property can be applied to quantitatively detect molecules invitro by measuring the related magnetic signals of nanoparticles bound with target molecules. One of the magnetic signals is the reduction in the mixed-frequency ac magnetic susceptibility of suspended magnetic nanoparticles due to the molecule-particle association. Many experimental results show empirically that the molecular-concentration dependent reduction in ac magnetic susceptibility follows the logistic function. In this study, it has been demonstrated that the logistic behavior is originated from the growth of particle sizes due to the molecule-particle association. The analytic relationship between the growth of particle sizes and the reduction in ac magnetic susceptibility is developed.

  12. Cross-language treatment generalisation

    PubMed Central

    Goral, Mira; Levy, Erika S.; Kastl, Rebecca

    2009-01-01

    Background Recent investigations of language gains following treatment in bilingual individuals with chronic aphasia appear to confirm early reports that not only the treated language but also the non-treated language(s) benefit from treatment. The evidence, however, is still suggestive, and the variables that may mitigate generalisation across languages warrant further investigation. Aims We set out to examine cross-language generalisation of language treatment in a trilingual speaker with mild chronic aphasia. Methods & Procedures Language treatment was administered in English, the participant’s second language (L2). The first treatment block focused on morphosyntactic skills and the second on language production rate. Measurements were collected in the treated language (English, L2) as well as the two non-treated languages: Hebrew (the participant’s first language, L1) and French (the participant’s third language, L3). Outcomes & Results The participant showed improvement in his production of selected morphosyntactic elements, such as pronoun gender agreement, in the treated language (L2) as well as in the non-treated French (L3) following the treatment block that focused on morphosyntactic skills. Speech rate also improved in English (L2) and French (L3) following that treatment block. No changes were observed in Hebrew, the participant’s L1. Conclusions Selective cross-language generalisation of treatment benefit was found for morphosyntactic abilities from the participant’s second language to his third language. PMID:20221311

  13. Anisotropy of the Magnetic Susceptibility of the Alnö alkaline and carbonatite igneous complex

    NASA Astrophysics Data System (ADS)

    Andersson, M.; Almqvist, B.; Malehmir, A.; Troll, V. R.; Snowball, I.; Lougheed, B.

    2013-12-01

    The Alnö igneous complex in central Sweden is one of the largest (radius ~2.5 km) of the few well-known alkaline and carbonatite ring-intrusions in the world. The lithologies span from alkaline silicate rocks (nepheline syenite, ijolite, and pyroxenite) to a range of carbonatite dykes (e.g. sövite) with variable composition. The depth extent, dip, and dip direction of the alkaline and carbonatite rocks have been inferred from surface geological mapping, and a dome-shaped magma chamber with the roof at ~2 km below the palaeosurface was inferred to have supplied steeply dipping radial dykes and (shallowly dipping) cone sheets. Recent high-resolution reflection seismic profiles and gravity and ground magnetic measurements suggest, in turn, a saucer-shaped magma chamber at ~3 km depth below present day land surface. To provide further insight into the internal flow mechanics of these dykes and into their emplacement mechanisms, we have measured the anisotropy of magnetic susceptibility (AMS). About 250 samples from 119 oriented cores were collected with a handheld drilling machine from 26 localities within the Alnö complex. Prior to preparation of discrete samples for AMS, the cores were measured for their density and for ultrasonic P- and S-wave velocities. Most of the sampling locations lie on a transect through the intrusion. Three locations have been sampled in detail, to determine the variation of AMS within individual carbonatite dykes. The AMS of samples were measured in low-field, using a KLY-2 Kappabridge. Bulk magnetic susceptibility ranges from 3.01e-5 to 2.50e-1 SI, and correlates with lithology. The sövites have the widest range of susceptibility (average 4.32e-2, with a range from 3.01e-5 to 2.50e-1 SI), whereas fenites have the lowest average susceptibility (average 2.06e-3, with a range from 9.86e-5 to 1.47e-2 SI); nepheline-syenite, ijolite and pyroxenite have susceptibilities between these two end member lithologies. Sövite consists mainly of

  14. Investigation of roadside pollution in Aliaga Industrial Zone (Izmir/Turkey) by using magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Timur, Emre

    2014-05-01

    Pollution of soils is significantly reducing environmental quality and affecting human health. As a condition for effective protection and remediation actions, the screening and detection of soil and sediment pollution has become increasingly important. The pollutants of most cases are usually heavy metals, organic contaminants and agricultural applications such as chemical fertilizers, pestisides and hormones. The aim of this study is to trace the distribution and concentration of contaminants in soils along roads carrying both appreciably high and low traffic along three roads around Aliaga industrial zone. Magnetic susceptibility (Bartington MS2E) is used for pollution mapping in the field. The distribution of the susceptibility values represents contaminated areas strongly influenced by traffic frequency, roadside topography, vegetation and meteorological conditions. It was determined that approximately 5 m along both sides of Canakkale-Izmir highway, which has a very high traffic density (250 car/min), shows very high susceptibility values in comparison with the rest of the profile. This value reduced to 2.4 m and 0.7 m along two side roads, which are 300 and 1100 m away from the highway. Also these roads were having traffic densities of 47 cars/min and 3 cars/min respectively. The measurements were repeated in summer and winter seasons in order to observe possible climate effects. Also soil samples were collected at 2 stations in both sides of the roads to compare the heavy metal content with the background values. According to geochemical data Fe-oxides are found to be responsible for the high values of magnetic susceptibility. It was determined that magnetic susceptibility is a rapid and cheap method for investigating potentially contaminated areas.

  15. Demonstrating and Measuring Relative Molar Magnetic Susceptibility Using a Neodymium Magnet

    ERIC Educational Resources Information Center

    Malerich, Charles; Ruff, Patricia K.; Bird, Aubrey

    2004-01-01

    An easy-to-see method for demonstrating and measuring the magnetic force between paramagnetic substance and a rare earth magnet is presented. The readily available trapezoid-shaped neodymium magnet and a low cost, easy-to-set-up, portable apparatus are used in the experiments.

  16. Metal-insulator transitions and magnetic susceptibility in doped cuprate compounds

    NASA Astrophysics Data System (ADS)

    Dzhumanov, S.; Kurbanov, U. T.; Khudayberdiev, Z. S.; Hafizov, A. R.

    2016-11-01

    Results are presented from a theoretical study of the possibility of hole carrier localization and metal-insulator transitions which show up in the temperature dependences of the magnetic susceptibility χ(T) of doped copper-oxide (cuprate) compounds. The criteria for metal-insulator transitions owing to strong hole-lattice interactions and the formation of very narrow polaron bands in these materials with reduced doping level x are analyzed. It is shown that these kinds of metal-insulator transitions occur in underdoped La2-xSrxCuO4 and YBa2Cu3O6+x cuprates (i.e., for x ranging from 0.04 to 0.12). The characteristic temperature dependences χ(T) of the HTSC cuprates are found for different doping levels. These results are in good agreement with experimental data on metal-insulator transitions and the magnetic susceptibility of the HTSC cuprates.

  17. Anisotropy of complex magnetic susceptibility as an indicator of strain and petrofabric in rocks bearing sulphides

    NASA Astrophysics Data System (ADS)

    Borradaile, G. J.; Puumala, M.; Stupavsky, M.

    1992-02-01

    A new method, anisotropy of complex magnetic susceptibility (ACMS), for determining the petrofabric of specimens with conductive minerals is developed. The method uses the same induction coil equipment and techniques that can be used for the measurement of the anisotropy of magnetic susceptibility (AMS). However, a higher (100 kHz) operating frequency emphasizes the electrical conductivity response and thus yields a measure of the anisotropy of electrical conductivity of the specimen. The method was tested on variably deformed plasticine samples containing aluminium fabric markers and on synthetic aggregates of pyrrhotite and talc-pyrrhotite mixtures deformed triaxially at a confining pressure of 200 MPa (2 kbar) by up to 35% homogeneous shortening. ACMS successfully defines the petrofabric and permits prediction of the principal directions of finite strain. The intensity of AMS and, to a lesser extent, of ACMS correlate with the strain ratio in these simple, coaxial, flattening plane strain experimental deformations on selected materials.

  18. Magnetic susceptibility measurements as proxy method to monitor soil pollution: development of experimental protocols for field surveys.

    PubMed

    D'Emilio, Mariagrazia; Chianese, Domenico; Coppola, Rosa; Macchiato, Maria; Ragosta, Maria

    2007-02-01

    In the framework of the development of new methods for measuring and monitoring soil pollution, this paper deals with the use of magnetic methodologies to monitor the heavy metals presence in soils. In particular it shows a procedure for collecting magnetic susceptibility measurements in order to interpret them as proxy variable for monitoring heavy metals in soils. Magnetic measurements are carried out using a magnetic susceptibility meter with two different probes for in situ field surveys. The experimental procedure is divided in two parts. In the first part we carry out laboratory tests aimed to evaluate, for both the probes, the effective investigation depth for soil, the measurement reproducibility under different conditions, and the influence of water content. We complete this part comparing in situ measurements obtained by means of two probes with different characteristics. In the second part we carry out tests to evaluate the relationships between heavy metal levels and magnetic susceptibility values of soil samples. We investigate the variability of the magnetic susceptibility measurements contaminating different soil samples with well known concentration of heavy metals. Moreover we study the correlation between magnetic susceptibility values and metal concentrations, determined by means of AAS, in soil samples collected during a field survey. Results suggest that a careful check of the experimental procedure play a crucial role for using magnetic susceptibility measurements for heavy metals in situ monitoring. This is very helpful both for improving the quality of data and for making simpler data interpretation.

  19. On the origin of magnetic a.c. susceptibility non-SRT anomalies in intermetallic compounds

    SciTech Connect

    Bartolome, J.; Garcia, L.M.; Lazaro, F.J.; Grincourt, Y.; Fuente, L.G. de la; Francisco, C. de; Munoz, J.M.; Fruchart, D.

    1994-03-01

    The anomaly detected in the magnetic a.c. susceptibility of many intermetallic compounds between 100 and 300 K, and in particular in Nd{sub 2}Fe{sub 14}B at 220 K, has been induced in a controlled manner by thermal annealing. The anomaly has been interpreted in terms of thermal activated processes of defects imposing their dynamical behavior on the domain walls coupled to them, thus solving the controversy on its origin.

  20. Magnetic susceptibility oscillation in neutron stars with the hadron-quark transition

    SciTech Connect

    Jiang, W. Z.; Van Giai, N.

    2006-11-02

    We analyze the de Hass-van Alphen (HVA) oscillation of magnetic susceptibility in the nuetron star matter using an analytic relativistic expression obtained before, showing that the oscillation frequency is proportional to the squared chemical potential and the reciprocal of the field, and is independent of the temperature. The numerical results for the HVA oscillation are also shown. A superposition of the HVA oscillations changes the oscillation properties drastically if the color deconfinement occurs at high densities.

  1. Magnetic susceptibility as a simple tracer for fluvial sediment source ascription during storm events.

    PubMed

    Rowntree, Kate M; van der Waal, Bennie W; Pulley, Simon

    2016-12-07

    Sediment tracing using a single tracer, low frequency magnetic susceptibility (Xlf), was used to apportion suspended sediment to geologically defined source areas and to interpret sediment source changes during flood events in the degraded catchment of the Vuvu River, a headwater tributary of the Mzimbubu River, South Africa. The method was tested as a simple tool for use by catchment managers concerned with controlling erosion. The geology of the 58 km(2) catchment comprises two distinct formations: basalt in the upper catchment with a characteristically high magnetic susceptibility and shales with a low magnetic susceptibility in the lower catchment. Application of an unmixing model incorporating a Monte Carlo uncertainty analysis showed that Xlf provided a means to assign the proportion of each geological province contributing to the river's sediment load. Grab water samples were collected at ten-minute intervals during flood events for subsequent analysis of suspended sediment concentration and the magnetic susceptibility of the filtered sediment. Two floods are presented in detail, the first represents a significant event at the start of the wet season (max. discharge 32 m(3) s(-1)); the second was a smaller flood (max discharge 14 m(3) s(-1)) that occurred a month later. Suspended sediment concentrations during the twelve monitored events showed a characteristic decline over the wet season. The main source of suspended sediment was shown to be from the mudstones in the lower catchment, which contributed 86% of the total measured load. The sediment dynamics during the two floods monitored in detail were quite different from each other. In the first the sediment concentration was high (11 g L(-1)), peaking after the flood peak. The Xlf value increased during the event, indicating that contribution to the sediment load from basalt in the upper catchment increased during the recession limb. In the second, smaller flood the sediment peak (6 g L(-1

  2. Magnetic susceptibility, specific heat and magnetic structure of CuNi{sub 2}(PO{sub 4}){sub 2}

    SciTech Connect

    Escobal, Jaione; Pizarro, Jose L.; Mesa, Jose L. . E-mail: joseluis.mesa@ehu.es; Larranaga, Aitor; Fernandez, Jesus Rodriguez; Arriortua, Maria I.; Rojo, Teofilo

    2006-10-15

    CuNi{sub 2}(PO{sub 4}){sub 2} phosphate has been synthesized by the ceramic method at 800 deg. C in air. The crystal structure consists of a three-dimensional skeleton constructed from MO{sub 4} (M{sup II} =Cu and Ni) planar squares and M{sub 2}O{sub 8} dimers with square pyramidal geometry, which are interconnected by (PO{sub 4}){sup 3-} oxoanions with tetrahedral geometry. The magnetic behavior has been studied on powdered sample by using susceptibility, specific heat and neutron diffraction data. The bimetallic copper(II)-nickel(II) orthophosphate exhibits a three-dimensional magnetic ordering at, approximately, 29.8 K. However, its complex crystal structure hampers any parametrization of the J-exchange parameter. The specific heat measurements exhibit a three-dimensional magnetic ordering ({lambda}-type) peak at 29.5 K. The magnetic structure of this phosphate shows ferromagnetic interactions inside the Ni{sub 2}O{sub 8} dimers, whereas the sublattice of Cu(II) ions presents antiferromagnetic couplings along the y-axis. The change of the sign in the magnetic unit-cell, due to the [1/2, 0, 1/2] propagation vector determines a purely antiferromagnetic structure. - Graphical abstract: Magnetic structure of CuNi2(PO4)2.

  3. Strain analysis in quartzites with negative magnetic susceptibility using AMS and EBSD data

    NASA Astrophysics Data System (ADS)

    Rajendraprasad Renjith, A.; Mamtani, Manish A.

    2016-04-01

    This study is being done with the objective of trying to understand whether the anisotropy of magnetic susceptibility (AMS) data can provide information about strain in quartzites with negative magnetic susceptibility. For this, nine quartzite samples have been collected from Rengali Province (located in the eastern part of India) with bulk magnetic susceptibility between -13.6 x 10-6 SI units and -3.06 x 10-6 SI units. Since these rocks did not show any visible foliation or lineation, AMS analysis was performed using KLY-4S Kappabridge and the orientation of three principal axes of the AMS ellipsoid (K1>K2>K3) were determined. Thin sections were prepared parallel to the K1K3 plane of the AMS ellipsoid (plane parallel to lineation and perpendicular to foliation), which is equivalent to the XZ plane of the strain ellipsoid. SEM based electron backscatter diffraction (EBSD) analysis, shape preferred orientation (SPO) analysis and strain analysis were carried out in these sections. Recently, Renjith et al. (2016) used the same samples to establish that the AMS in quartzites gives information about the SPO and not the CPO. To further evaluate the robustness of AMS in strain analysis, the authors have integrated the degree of magnetic anisotropy (Pj - a measure of the eccentricity of AMS ellipsoid; Tarling and Hrouda, 1993) with the intensity of SPO (κ ; Piazolo and Passchier, 2002), and the strain (E - calculated using AMOCADO; Gerik and Kruhl, 2009) from the same samples from Rengali. EBSD data were used as the basis for the above calculations. Whilst the orientation of long axis of quartz grains from EBSD statistical data was used to calculate κ , the grain boundary map generated from EBSD analysis was used as the basis to determine strain (E). It is found that the sample with minimum Pj also has a minimum κ and E, and vice-versa. Hence it is concluded that one-to-one correlation exists between the degree of magnetic anisotropy, strain and intensity of SPO in

  4. Ferromagnetic ordering in NpAl2: Magnetic susceptibility and 27Al nuclear magnetic resonance

    NASA Astrophysics Data System (ADS)

    Martel, L.; Griveau, J.-C.; Eloirdi, R.; Selfslag, C.; Colineau, E.; Caciuffo, R.

    2015-08-01

    We report on the magnetic properties of the neptunium based ferromagnetic compound NpAl2. We used magnetization measurements and 27Al NMR spectroscopy to access magnetic features related to the paramagnetic and ordered states (TC=56 K). While very precise DC SQUID magnetization measurements confirm ferromagnetic ordering, they show a relatively small hysteresis loop at 5 K reduced with a coercive field HCo~3000 Oe. The variable offset cumulative spectra (VOCS) acquired in the paramagnetic state show a high sensitivity of the 27Al nuclei spectral parameters (Knight shifts and line broadening) to the ferromagnetic ordering, even at room temperature.

  5. Low-frequency low-field magnetic susceptibility of ferritin and hemosiderin.

    PubMed

    Allen, P D; St Pierre, T G; Chua-anusorn, W; Ström, V; Rao, K V

    2000-02-21

    Low-frequency low-field magnetic susceptibility measurements were made on four samples of mammalian tissue iron oxide deposits. The samples comprised: (1) horse spleen ferritin; (2) dugong liver hemosiderin; (3) thalassemic human spleen ferritin; and (4) crude thalassemic human spleen hemosiderin. These samples were chosen because Mössbauer spectroscopic measurements on the samples indicated that they exemplified the variation in magnetic and mineral structure found in mammalian tissue iron oxide deposits. The AC-magnetic susceptometry yielded information on the magnetization kinetics of the four samples indicating samples 1, 2, and 3 to be superparamagnetic with values of around 10(11) s(-1) for the pre-exponential frequency factor in the Néel-Arrhenius equation and values for characteristic magnetic anisotropy energy barriers in the range 250-400 K. Sample 4 was indicated to be paramagnetic at all temperatures above 1.3 K. The AC-magnetic susceptometry data also indicated a larger magnetic anisotropy energy distribution in the dugong liver sample compared with samples 1 and 3 in agreement with previous Mössbauer spectroscopic data on these samples. At temperatures below 200 K, samples 1-3 exhibited Curie-Weiss law behavior, indicating weak particle-particle interactions tending to favor antiparallel alignment of the particle magnetic moments. These interactions were strongest for the dugong liver hemosiderin, possibly reflecting the smaller separation between mineral particles in this sample. This is the first magnetic susceptometry study of hemosiderin iron deposits and demonstrates that the AC-magnetic susceptometry technique is a fast and informative method of studying such tissue iron oxide deposits.

  6. Magnetic susceptibility of hcp iron and the seismic anisotropy of Earth's inner core

    NASA Astrophysics Data System (ADS)

    Grechnev, G. E.; Ahuja, R.; Eriksson, O.

    2003-08-01

    The seismic anisotropy of the Earth’s core is believed to be due to a preferred orientation of hexagonal close packed (hcp) iron crystals that constitute the dominating element in the inner core. In this connection, the magnetic properties of the hcp iron in an external magnetic field are very interesting and are studied here by employing an ab initio full-potential linear muffin tin orbital method. By this means the magnetic susceptibility χ of hcp iron and its anisotropy energy for pressures and temperatures corresponding to the Earth’s inner core conditions have been evaluated in the framework of the local spin density approximation. The accuracy of this method has been validated by calculating the anisotropic susceptibility of paramagnetic transition metals that form in the hcp crystal structure at ambient conditions. Our calculations demonstrate that for hcp iron the anisotropy of χ is dependent on the c/a ratio. In conjunction with recent data on the c/a ratio and elastic constants of hcp iron, the magnetic anisotropy can explain the seismic anisotropy of the Earth’s inner core.

  7. Magnetic susceptibility and the spatial variability of heavy metals in soils developed on basalt

    NASA Astrophysics Data System (ADS)

    Cervi, Eduardo Cimino; da Costa, Antonio Carlos Saraiva; de Souza Junior, Ivan Granemann

    2014-12-01

    Topsoil magnetic susceptibility (κ) is a fast and convenient method used to detect potentially polluted areas by heavy metals. Topsoil measurements are carried out in situ with Bartington MS2D loop sensor, designed to measure the magnetic susceptibility of top 10 cm of soil and detect 90% of the total signal from a depth of 6 cm. However, soils developed on basalt are difficult to assess due to their large amounts of ferrimagnetic minerals. The aim of this study was evaluate the applicability of κ to discriminate anthropogenic/lithogenic environments characterized by different parent materials in the city of Maringá/Brazil. In this paper, topsoil susceptibility (κ) was measured in 66 urban soils using a Bartington MS2D loop sensor. To investigate the magnetic background levels, samples of a Rhodic Ferralsol profile were measured using a laboratory MS2B sensor. X-ray diffractometry (XRD) analysis was carried out to verify the mineralogical composition of the different lithology. Cu, Fe, Ni, Mn, Pb and Zn concentrations were measured in 29 topsoil samples. The κ values ranged from 316 × 10- 5 SI in a sandstone region to 6,945 × 10- 5 SI in soils developed on basalt. The χfd values of urban topsoil varied from 2% to 11.3%. Lower values of κ and χfd in the sandstone region indicated that the lithogenic contribution is of primary significance. Significant positive correlations between κ and Cu, Fe and Mn are related to the parent material, enriched in iron oxides, as verified by XRD. The background values (mean of 4,235 × 10- 8 m3 kg- 1) were higher in subsoil, suggesting the inexistence of anthropogenic pollution. The topsoil susceptibility was efficient for distinguish different lithogenic environments. Although anthropogenic pollution in soils developed on basalt is difficult to assess due to the high natural background, our results suggest that heavy metal contents are not related to the human activity.

  8. Characterization of tissue magnetic susceptibility-induced distortions for MRIgRT

    SciTech Connect

    Stanescu, T.; Wachowicz, K.; Jaffray, D. A.

    2012-12-15

    Purpose: MR image geometric integrity is one of the building blocks of MRI-guided radiotherapy. In particular, tissue magnetic susceptibility-induced effects are patient-dependent and their behavior is difficult to assess and predict. In this study, the authors investigated in detail the characteristics of susceptibility ({chi}) distortions in the context of MRIgRT, including the case of two common MR-linac system configurations. Methods: The magnetic field distortions were numerically simulated for several imaging parameters and anatomical sites, i.e., brain, lung, pelvis (with air pockets), and prostate. The simulation process consisted of (a) segmentation of patient CT data into susceptibility relevant anatomical volumes (i.e., soft-tissue, bone and air/lung), (b) conversion of CT data into susceptibility masks by assigning bulk {chi} values to the structures defined at (a), (c) numerical computations of the local magnetic fields by using a finite difference algorithm, and (d) generation of the geometric distortion maps from the magnetic field distributions. For each patient anatomy, the distortions were quantified at the interfaces of anatomical structures with significantly different {chi} values. The analysis was performed for two specific orientations of the external main magnetic field (B{sub 0}) characteristic to the MR-linac systems, specifically along the z-axis for a bore MR scanner and in the (x,y)-plane for a biplanner magnet. The magnetic field local perturbations were reported in ppm. The metrics used to quantify the geometric distortions were the maximum, mean, and range of distortions. The numerical simulation algorithm was validated using phantom data measurements. Results: Susceptibility-induced distortions were determined for both quadratic and patient specific geometries. The numerical simulations showed a good agreement with the experimental data. The measurements were acquired at 1.5 and 3 T and with an encoding gradient varying between 3

  9. Magnetic susceptibility and relation to initial 87Sr/86Sr for granitoids of the central Sierra Nevada, California

    USGS Publications Warehouse

    Bateman, P.C.; Dodge, F.C.W.; Kistler, R.W.

    1991-01-01

    Measurement of the magnetic susceptibility of more than 6000 samples of granitic rock from the Mariposa 1?? by 2?? quadrangle, which crosses the central part of the Sierra Nevada batholith between 37?? and 38??N latitude, shows that magnetic susceptibility values are above 10-2 SI units in the east and central parts of the batholith and drop abruptly to less than 10-3 SI units in the western foothills. In a narrow transitional zone, intermediate values (10-3 to 10-2) prevail. Magnetic susceptibility appears to decrease slightly westward within the zones of both high and low values. Magnetic susceptibility in plutonic rocks is chiefly a function of the abundance of magnetite, which depends, in turn, on the total iron content of the rocks and their oxidation ratio. Correlations of magnetic susceptibility with initial 87Sr/86Sr suggest that oxidation ratios have been inherited from the source regions for the magmas from which the rocks crystallized. Reduction of Fe3+ to Fe2+ by organic carbon or other reducing substances may also have affected magnetic susceptibility. -from Authors

  10. 150 000 Years of Loess Deposition in Interior Alaska as Told by Magnetic Susceptibility

    NASA Astrophysics Data System (ADS)

    Jensen, B. J. L.; Evans, M. E.; Froese, D. G.; Kravchinsky, V. A.

    2015-12-01

    The Halfway House loess deposit in interior Alaska contains a well-studied and complex paleomagnetic and paleoenvironmental record. Unfortunately, a lack of chronologic control has made it difficult to interpret the results of these studies. Detailed reexamination of stratigraphy, paleomagnetics and tephrostratigraphy reveals a relatively complete marine isotope stage (MIS) 6 to Holocene record constrained by the Old Crow (124 ± 10 ka), VT (106 ± 10 ka), Sheep Creek-Klondike (ca. 80 ka), Dominion Creek (77 ± 8 ka) and Dawson (ca. 30.2 cal ka BP) tephras. Two well-developed paleosols are shown to have formed during Marine Isotope Stages (MIS) 5e and 5a, while MIS 5c and 5b are either poorly represented or absent. A magnetic excursion is identified as the post-Blake excursion (94.1 ± 7.8 ka) and provides independent age control while adding to an increasing body of evidence that Alaskan loess is a detailed recorder of variations of the Earth's magnetic field over time. High-resolution magnetic susceptibility profiles placed into this new chronostratigraphic framework help refine loess deposition models for the interior of Alaska, while providing a means to correlate to previous magnetic studies at this site. The profiles support the hypothesis that wind-intensity is the main variable controlling fluctuations in susceptibility, with the highest susceptibility during peak glacial times and the lowest values in paleosols representing interglacials. However, the correlation of the susceptibility record to global marine d18O records is complicated by highly variable accumulation rates. We find the lowest rates of accumulation during peak warm and cold stages, while abrupt increases are associated with periods of transition between marine isotope stages, represented by intermediate susceptibility values. Previous accumulation models for Alaska have emphasized the role of surface roughness as an important variable controlling loess accumulation. However our results

  11. AC susceptibility as a tool to probe the dipolar interaction in magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Landi, Gabriel T.; Arantes, Fabiana R.; Cornejo, Daniel R.; Bakuzis, Andris F.; Andreu, Irene; Natividad, Eva

    2017-01-01

    The dipolar interaction is known to substantially affect the properties of magnetic nanoparticles. This is particularly important when the particles are kept in a fluid suspension or packed within nano-carriers. In addition to its usual long-range nature, in these cases the dipolar interaction may also induce the formation of clusters of particles, thereby strongly modifying their magnetic anisotropies. In this paper we show how AC susceptibility may be used to obtain information regarding the influence of the dipolar interaction in a sample. We develop a model which includes both aspects of the dipolar interaction and may be fitted directly to the susceptibility data. The usual long-range nature of the interaction is implemented using a mean-field approximation, whereas the particle-particle aggregation is modeled using a distribution of anisotropy constants. The model is then applied to two samples studied at different concentrations. One consists of spherical magnetite nanoparticles dispersed in oil and the other of cubic magnetite nanoparticles embedded on polymeric nanospheres. We also introduce a simple technique to address the presence of the dipolar interaction in a given sample, based on the height of the AC susceptibility peaks for different driving frequencies.

  12. Single crystal magnetic structure and susceptibility of CoSe{sub 2}O{sub 5}

    SciTech Connect

    Rodriguez, Efrain E.; Cao, Huibo; Haiges, Ralf; Melot, Brent C.

    2016-04-15

    The structure of CoSe{sub 2}O{sub 5} consists of one-dimensional ribbons of edge-sharing CoO{sub 6} octahedra bound together by polyanionic subunits of Se{sub 2}O{sub 5}. Previous work on polycrystalline samples reported a canted antiferromagnetic arrangement of the magnetic moments below the ordering temperature of 8.5 K. Here, we report a single crystal investigation using variable temperature and field magnetic susceptibility and low-temperature neutron diffraction to more precisely characterize the nature of the magnetic ground state of CoSe{sub 2}O{sub 5}. Contrary to previous reports, we find that the single crystal magnetic structure shows no canting of the antiferromagnetic ground state, and in the process have identified several field-induced changes to the magnetization. We discuss these results in the context of the revised magnetic structure and highlight the importance of crystal growth for the accurate characterization of these properties.

  13. An adapted Coffey model for studying susceptibility losses in interacting magnetic nanoparticles

    PubMed Central

    Osaci, Mihaela

    2015-01-01

    Summary Background: Nanoparticles can be used in biomedical applications, such as contrast agents for magnetic resonance imaging, in tumor therapy or against cardiovascular diseases. Single-domain nanoparticles dissipate heat through susceptibility losses in two modes: Néel relaxation and Brownian relaxation. Results: Since a consistent theory for the Néel relaxation time that is applicable to systems of interacting nanoparticles has not yet been developed, we adapted the Coffey theoretical model for the Néel relaxation time in external magnetic fields in order to consider local dipolar magnetic fields. Then, we obtained the effective relaxation time. The effective relaxation time is further used for obtaining values of specific loss power (SLP) through linear response theory (LRT). A comparative analysis between our model and the discrete orientation model, more often used in literature, and a comparison with experimental data from literature have been carried out, in order to choose the optimal magnetic parameters of a nanoparticle system. Conclusion: In this way, we can study effects of the nanoparticle concentration on SLP in an acceptable range of frequencies and amplitudes of external magnetic fields for biomedical applications, especially for tumor therapy by magnetic hyperthermia. PMID:26665090

  14. Frequency dependence of the absorption component of the magnetic susceptibility in superconducting Y1Ba2Cu3O7

    NASA Astrophysics Data System (ADS)

    Ducharme, S.; Durny, R.; Hautala, J.; Symko, O. G.; Taylor, P. C.

    Measurements of an apparent magnetic-field-dependent absorption (imaginary part of the a.c. magnetic susceptibility) in superconducting Y1Ba2Cu3O7 ceramics and crystals are reported. The absorption, which is observed over a wide range of frequencies but only when the material is below the superconducting transition temperature, is characterized by a narrow (about 30 Gauss FWHM at 6 MHz) peak and a wide (greater than 10 kG) feature, both of which are maximum at zero magnetic field. The absorption strength varies approximately as one over the square root of the frequency. The unusual magnetic-field-dependent peaks in the magnetic susceptibility are inherent in single grains and therefore do not originate from intergrain Josephson currents or multigrain (i.e., percolative) loops. The susceptibility peaks must be due to bulk behavior, interactions at grain surfaces, intragrain current loops, or intragrain Josephson junctions.

  15. The utilisation of magnetic susceptibility as a vector toward mineralisation in common rock and ore forming minerals.

    NASA Astrophysics Data System (ADS)

    English, Matthew; Raub, Tim

    2015-04-01

    Aeromagnetic and ground magnetic surveys of mineral deposits and prospective terrain are a fundamental technique used in mining and economic geology. Inversion of survey data to source parameters (i.e., identification of ore zones) is often simplified by assuming a single, canonical or 'average' value for the magnetic susceptibility of each mappable unit. In some mineral deposits, canonical magnetic susceptibility values for several dominant ore and accessory minerals will be used to calculate mineral concentrations, 3-D distributions, etc. In general, magnetic susceptibility is widely recognised by economic geologists as a fundamental, easily-measured tool used to better understand the prospectivity of ore deposits. Despite this, the quantitative application of magnetic susceptibility, in context of detailed ore petrology, is still a developing field yet one with great potential. In order to assess to what extent, and in which systems, magnetic susceptibility is a vector toward mineralisation, we present aspects of an extensive database of single crystal and ore mineral aggregate samples. This reveals trends and magnitudes for several important rock-forming and ore-associated minerals during alteration, paragenesis, and enrichment. For example, current literature canonical values show that the magnetic susceptibility for pure quartz is strongly diamagnetic but ranges between -1.78x10-5 and -1.00x10-5 (k, vol. SI). However, metamorphic bull quartz and chrysoprase are commonly paramagnetic, with common values for chrysoprase as high as 2.11x10-3. In contrast, measurements from rose quartz samples are lower than those described for pure quartz with modal measurements as low as -2.08x10-5. Measurements for rock crystal quartz form a distribution best described by the canonical diamagnetic value of -1.40x10-5. Modelling should take into account that rock crystal quartz is rarely the best petrological analogue at deposit-scale or in a quartzose terrain. The difference

  16. Young Australian Indigenous Students' Growing Pattern Generalisations: The Role of Gesture When Generalising

    ERIC Educational Resources Information Center

    Miller, Jodie

    2014-01-01

    This paper explores how young Indigenous students' (Year 2 and 3) generalise growing patterns. Piagetian clinical interviews were conducted to determine how students articulated growing pattern generalisations. Two case studies are presented displaying how students used gesture to support and articulate their generalisations of growing patterns.…

  17. EPR and magnetic susceptibility investigation of iron-zinc-phosphate glass ceramics

    SciTech Connect

    Popa, A.; Stefan, R.; Bosca, M.; Dan, V.; Pop, V.; Pascuta, P.

    2013-11-13

    (Fe{sub 2}O{sub 3}){sub x}⋅(P{sub 2}O{sub 5}){sub 40}⋅(ZnO){sub 60−x} glass ceramics containing different concentrations of Fe{sub 2}O{sub 3} ranging from 1 to 20 mol% were obtained by heat treatment of glass samples at 650 °C for 2 h. The structural and magnetic properties of these glass ceramics were investigated by means of electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. The EPR spectra of the studied samples revealed absorptions centered at g ≈ 2.0 and 4.3. The compositional variations of the intensity and line width of these absorption lines was interpreted in terms of the variation in Fe{sup 3+} and Fe{sup 2+} ions concentration in the glass ceramics as well as the interaction between the iron ions. The magnetic susceptibility data evidenced the presence of both Fe{sup 3+} and Fe{sup 2+} ions, with their relative content depending on the Fe{sub 2}O{sub 3} concentration. Dipolar and superexchange interactions involving iron ions were revealed depending on the iron content of the sample.

  18. Design and development of novel MRI compatible zirconium- ruthenium alloys with ultralow magnetic susceptibility.

    PubMed

    Li, H F; Zhou, F Y; Li, L; Zheng, Y F

    2016-04-19

    In the present study, novel MRI compatible zirconium-ruthenium alloys with ultralow magnetic susceptibility were developed for biomedical and therapeutic devices under MRI diagnostics environments. The results demonstrated that alloying with ruthenium into pure zirconium would significantly increase the strength and hardness properties. The corrosion resistance of zirconium-ruthenium alloys increased significantly. High cell viability could be found and healthy cell morphology observed when culturing MG 63 osteoblast-like cells and L-929 fibroblast cells with zirconium-ruthenium alloys, whereas the hemolysis rates of zirconium-ruthenium alloys are <1%, much lower than 5%, the safe value for biomaterials according to ISO 10993-4 standard. Compared with conventional biomedical 316L stainless steel, Co-Cr alloys and Ti-based alloys, the magnetic susceptibilities of the zirconium-ruthenium alloys (1.25 × 10(-6) cm(3)·g(-1)-1.29 × 10(-6) cm(3)·g(-1) for zirconium-ruthenium alloys) are ultralow, about one-third that of Ti-based alloys (Ti-6Al-4V, ~3.5 × 10(-6) cm(3)·g(-1), CP Ti and Ti-6Al-7Nb, ~3.0 × 10(-6) cm(3)·g(-1)), and one-sixth that of Co-Cr alloys (Co-Cr-Mo, ~7.7 × 10(-6) cm(3)·g(-1)). Among the Zr-Ru alloy series, Zr-1Ru demonstrates enhanced mechanical properties, excellent corrosion resistance and cell viability with lowest magnetic susceptibility, and thus is the optimal Zr-Ru alloy system as therapeutic devices under MRI diagnostics environments.

  19. Design and development of novel MRI compatible zirconium- ruthenium alloys with ultralow magnetic susceptibility

    PubMed Central

    Li, H.F.; Zhou, F.Y.; Li, L.; Zheng, Y.F.

    2016-01-01

    In the present study, novel MRI compatible zirconium-ruthenium alloys with ultralow magnetic susceptibility were developed for biomedical and therapeutic devices under MRI diagnostics environments. The results demonstrated that alloying with ruthenium into pure zirconium would significantly increase the strength and hardness properties. The corrosion resistance of zirconium-ruthenium alloys increased significantly. High cell viability could be found and healthy cell morphology observed when culturing MG 63 osteoblast-like cells and L-929 fibroblast cells with zirconium-ruthenium alloys, whereas the hemolysis rates of zirconium-ruthenium alloys are <1%, much lower than 5%, the safe value for biomaterials according to ISO 10993-4 standard. Compared with conventional biomedical 316L stainless steel, Co–Cr alloys and Ti-based alloys, the magnetic susceptibilities of the zirconium-ruthenium alloys (1.25 × 10−6 cm3·g−1–1.29 × 10−6 cm3·g−1 for zirconium-ruthenium alloys) are ultralow, about one-third that of Ti-based alloys (Ti–6Al–4V, ~3.5 × 10−6 cm3·g−1, CP Ti and Ti–6Al–7Nb, ~3.0 × 10−6 cm3·g−1), and one-sixth that of Co–Cr alloys (Co–Cr–Mo, ~7.7 × 10−6 cm3·g−1). Among the Zr–Ru alloy series, Zr–1Ru demonstrates enhanced mechanical properties, excellent corrosion resistance and cell viability with lowest magnetic susceptibility, and thus is the optimal Zr–Ru alloy system as therapeutic devices under MRI diagnostics environments. PMID:27090955

  20. Design and development of novel MRI compatible zirconium- ruthenium alloys with ultralow magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Li, H. F.; Zhou, F. Y.; Li, L.; Zheng, Y. F.

    2016-04-01

    In the present study, novel MRI compatible zirconium-ruthenium alloys with ultralow magnetic susceptibility were developed for biomedical and therapeutic devices under MRI diagnostics environments. The results demonstrated that alloying with ruthenium into pure zirconium would significantly increase the strength and hardness properties. The corrosion resistance of zirconium-ruthenium alloys increased significantly. High cell viability could be found and healthy cell morphology observed when culturing MG 63 osteoblast-like cells and L-929 fibroblast cells with zirconium-ruthenium alloys, whereas the hemolysis rates of zirconium-ruthenium alloys are <1%, much lower than 5%, the safe value for biomaterials according to ISO 10993-4 standard. Compared with conventional biomedical 316L stainless steel, Co–Cr alloys and Ti-based alloys, the magnetic susceptibilities of the zirconium-ruthenium alloys (1.25 × 10‑6 cm3·g‑1–1.29 × 10‑6 cm3·g‑1 for zirconium-ruthenium alloys) are ultralow, about one-third that of Ti-based alloys (Ti–6Al–4V, ~3.5 × 10‑6 cm3·g‑1, CP Ti and Ti–6Al–7Nb, ~3.0 × 10‑6 cm3·g‑1), and one-sixth that of Co–Cr alloys (Co–Cr–Mo, ~7.7 × 10‑6 cm3·g‑1). Among the Zr–Ru alloy series, Zr–1Ru demonstrates enhanced mechanical properties, excellent corrosion resistance and cell viability with lowest magnetic susceptibility, and thus is the optimal Zr–Ru alloy system as therapeutic devices under MRI diagnostics environments.

  1. Self-assembled magnetic bead biosensor for measuring bacterial growth and antimicrobial susceptibility testing.

    PubMed

    Kinnunen, Paivo; McNaughton, Brandon H; Albertson, Theodore; Sinn, Irene; Mofakham, Sima; Elbez, Remy; Newton, Duane W; Hunt, Alan; Kopelman, Raoul

    2012-08-20

    Bacterial antibiotic resistance is one of the major concerns of modern healthcare worldwide, and the development of rapid, growth-based, antimicrobial susceptibility tests is key for addressing it. The cover image shows a self-assembled asynchronous magnetic bead rotation (AMBR) biosensor developed for rapid detection of bacterial growth. Using the biosensors, the minimum inhibitory concentration of a clinical E. coli isolate can be measured within two hours, where currently tests take 6-24 hours. A 16-well prototype is also constructed for simple and robust observation of the self-assembled AMBR biosensors.

  2. Technique for magnetic susceptibility determination in the highly doped semiconductors by electron spin resonance

    SciTech Connect

    Veinger, A. I.; Zabrodskii, A. G.; Tisnek, T. V.; Goloshchapov, S. I.; Semenikhin, P. V.

    2014-08-20

    A method for determining the magnetic susceptibility in the highly doped semiconductors is considered. It is suitable for the semiconductors near the metal - insulator transition when the conductivity changes very quickly with the temperature and the resonance line form distorts. A procedure that is based on double integration of the positive part of the derivative of the absorption line having a Dyson shape and takes into account the depth of the skin layer is described. Analysis is made for the example of arsenic-doped germanium samples at a rather high concentration corresponding to the insulator-metal phase transition.

  3. Magnetic susceptibility, artifact volume in MRI, and tensile properties of swaged Zr-Ag composites for biomedical applications.

    PubMed

    Imai, Haruki; Tanaka, Yoji; Nomura, Naoyuki; Doi, Hisashi; Tsutsumi, Yusuke; Ono, Takashi; Hanawa, Takao

    2017-02-01

    Zr-Ag composites were fabricated to decrease the magnetic susceptibility by compensating for the magnetic susceptibility of their components. The Zr-Ag composites with a different Zr-Ag ratio were swaged, and their magnetic susceptibility, artifact volume, and mechanical properties were evaluated by magnetic balance, three-dimensional (3-D) artifact rendering, and a tensile test, respectively. These properties were correlated with the volume fraction of Ag using the linear rule of mixture. We successfully obtained the swaged Zr-Ag composites up to the reduction ratio of 96% for Zr-4, 16, 36, 64Ag and 86% for Zr-81Ag. However, the volume fraction of Ag after swaging tended to be lower than that before swaging, especially for Ag-rich Zr-Ag composites. The magnetic susceptibility of the composites linearly decreased with the increasing volume fraction of Ag. No artifact could be estimated with the Ag volume fraction in the range from 93.7% to 95.4% in three conditions. Young's modulus, ultimate tensile strength (UTS), and 0.2% yield strength of Zr-Ag composites showed slightly lower values compared to the estimated values using a linear rule of mixture. The decrease in magnetic susceptibility of Zr and Ag by alloying or combining would contribute to the decrease of the Ag fraction, leading to the improvement of mechanical properties.

  4. Supersymmetric backgrounds and generalised special holonomy

    NASA Astrophysics Data System (ADS)

    Coimbra, André; Strickland-Constable, Charles; Waldram, Daniel

    2016-06-01

    We define intrinsic torsion in generalised geometry and use it to introduce a new notion of generalised special holonomy. We then consider generic warped supersymmetric flux compactifications of M theory and Type II of the form {{{R}}}D-{1,1}× M. Using the language of {E}d(d)× {{{R}}}+ generalised geometry, we show that, for D≥slant 4, preserving minimal supersymmetry is equivalent to the manifold M having generalised special holonomy and list the relevant holonomy groups. We conjecture that this result extends to backgrounds preserving any number of supersymmetries. As a prime example, we consider { N }=1 in D = 4. The corresponding generalised special holonomy group is {SU}(7), giving the natural M theory extension to the notion of a G 2 manifold, and, for Type II backgrounds, reformulating the pure spinor {SU}(3)× {SU}(3) conditions as an integrable structure.

  5. Influence of the angle between cleavage and bedding on the anisotropy of magnetic susceptibility and the degree of phyllosilicate preferred orientation

    NASA Astrophysics Data System (ADS)

    Debacker, T. N.; Sintubin, M.

    2003-04-01

    Due to the common scarcity of strain markers and the often fine-grained lithologies, performing strain analyses in slate belts may be difficult. As an alternative, one may use methods such as phyllosilicate preferred orientation (X-ray pole figure goniometry) and anisotropy of magnetic susceptibility (AMS). However, a large number of factors influence the results of these analytical methods. One of the factors is the angle between cleavage and bedding. The study area is the Brabant Massif, a single-phase deformed, low-grade slate belt in N-Belgium consisting of a steep Cambrian core surrounded by Ordovician-Silurian sequences. In the southern part of the Cambrian core, the transition between steeply plunging folds, considered typical for the steep core, and gently plunging folds, considered characteristic for the peripheral Ordovician-Silurian sequences, occurs in homogeneous mudstones of the Lower Cambrian Oisquercq Formation. In these deposits mica and chlorite show a similar degree of preferred orientation. Mica is always aligned along the cleavage, whereas chlorite is aligned along the bedding. Clear intersection pole figure patterns characterise samples with large cleavage/bedding angles, whereas flattening fabrics only become apparent for samples with small cleavage/bedding angles. For both mica and chlorite, the degree of preferred orientation is higher for samples with small cleavage/bedding angles. The magnetic fabric shows prolate susceptibility ellipsoids for samples with large cleavage/bedding angles and oblate susceptibility ellipsoids for samples with small cleavage/bedding angles (cf. Housen et al., 1993). The short axis of the susceptibility ellipsoid is generally oriented perpendicular to bedding, occasionally perpendicular to cleavage or with an intermediate orientation. The long axis of the susceptibility ellipsoid is always parallel to the cleavage/bedding intersection. The shape parameter T shows an almost linear relationship with respect to

  6. RECONSTRUCTING PALEO-SMT POSITIONS ON THE CASCADIA MARGIN USING MAGNETIC SUSCEPTIBILITY

    SciTech Connect

    Johnson, Joel; Phillips, Stephen

    2014-09-30

    Magnetic susceptibility (κ) is a mixed signal in marine sediments, representing primary depositional and secondary diagenetic processes. Production of hydrogen sulfide via anaerobic oxidation of methane (AOM) at the sulfate-methane transition (SMT) and organoclastic sulfate reduction above the SMT can result in the dissolution of iron oxides, altering κ in sediments in methane gas and gas hydrate bearing regions. We investigated records of κ on the Cascadia margin (ODP Sites 1249 and 1252; IODP Site 1325) using a Zr/Rb heavy mineral proxy from XRF core scanning to identify intervals of primary detrital magnetic susceptibility and intervals and predict intervals affected by magnetite dissolutions. We also measured total sulfur content, grain size distributions, total organic carbon (TOC) content, and magnetic mineral assemblage. The upper 100 m of Site 1252 contains a short interval of κ driven by primary magnetite, with multiple intervals (> 90 m total) of decreased κ correlated with elevated sulfur content, consistent with dissolution of magnetite and re-precipitation of pyrite. In the upper 90 m of Site 1249, κ is almost entirely altered by diagenetic processes, with much of the low κ explained by a high degree of pyritization, and some intervals affected by the precipitation of magnetic iron sulfides. At Site 1325, κ between 0-20 and 51-73 mbsf represents primary mineralogy, and in the interval 24-51 mbsf, κ may be reduced due to pyritization. This integrated approach allows for a prediction of primary κ and the amount of κ loss at each site when compared to actual κ measurements. In the case of magnetite dissolution and full pyritization, these drawdowns in κ are supported by sulfur measurements, and the exposure times of magnetite to hydrogen sulfide can be modeled. The presence of methane and methane hydrates at these sites, as well as large variations in TOC content, suggest that the past migration rates of the SMT and variation in sulfate

  7. [Heavy Metals Accmultio in the Caofeidian Reclamation Soils: Indicated by Soil Magnetic Susceptibility].

    PubMed

    Xue, Yong; Zhou, Qian; Li, Yuan; Zhang, Hai-bo; Hu, Xue-feng; Luo, Yong-ming

    2016-04-15

    The environmental magnetism method has been widely applied to identify soil heavy metal pollution, which is characterized by simplicity, efficiency, non-destructivity and sensitivity. The present study used magnetic susceptibility to assess the accumulation of heavy metals in soils of the Caofeidian industrial zone which is a typical reclamation area in northern China. The study area was divided into three sub-zones based on the function, including industrial zone, living zone, natural tidal flat and wetland. A total of 35 topsoil samples (0-10 cm) and 3 soil profiles were collected from the three sub-zones. Magnetic susceptibility (X(lf)), iron oxide (Fe2O3) contents and heavy metals contents (Cr, Ni, Cu, Zn, As, Pb, Mn and V) of the samples were analyzed. The results showed that X(lf) values and heavy metals contents exhibited higher spatial variability in the top soil of the industrial zone, indicating the severe impacts of industrial activities. In the soil profiles of the industrial and living zones, all heavy metals were enriched to different degrees in the upper layer (0-20 cm). However, there was no significant change of heavy metal contents in the soil profiles of tidal flat which was far from the industrial area. The X(lf) value was significantly (P < 0.01) positively correlated with the contents of Fe2O3, Ni, Cu, As and V in the industrial top soil. This indicated that X(lf) could be used as an indicator for heavy metal accumulation in the industrial zone. However, the X(lf) value was not suitable to be an indicator to show the heavy metal accumulation in the soils of living zone and natural tidal flat. This might be associated with the different sources of magnetic materials among the different sub-zones and the special characteristics of the soils in the tidal flat and wetland.

  8. Exploiting the Temperature Dependence of Magnetic Susceptibility to Control Convection in Fundamental Studies of Solidification Phenomena

    NASA Technical Reports Server (NTRS)

    Seybert, C. D.; Evans, J. W.; Leslie, Fred; Jones, W. K., Jr.

    2000-01-01

    It is well known that convection is a dominant mass transport mechanism when materials are solidified on Earth's surface. This convection is caused by gradients in density (and therefore gravitational force) that are brought about by gradients in temperature, composition or both. Diffusion of solute is therefore dwarfed by convection and the study of fundamental parameters, such as dendrite tip shape and growth velocity in the absence of convection is nearly impossible. Significant experimental work has therefore been carried out in orbiting laboratories with the intent of minimizing convection by minimizing gravity. One of the best known experiments of this kind is the Isothermal Dendritic Growth Experiment (IDGE), supported by NASA. Naturally such experiments are costly and one objective of the present investigation is to develop an experimental method whereby convection can be- halted, in solidification and other experiments, on the surface. A second objective is to use the method to minimize convection resulting from the residual accelerations suffered by experiments in microgravity. The method to be used to minimize convection relies on the dependence of the magnetic susceptibility of a fluid on temperature or composition (whichever is driving convection). All materials experience a force when placed in a magnetic field gradient. The direction and magnitude of that force depend on the magnetic susceptibility of the material. Consequently the force will vary if the susceptibility varies with temperature or composition. With a magnetic field gradient in the right direction (typically upward) and of the right magnitude, this variation in the magnetic force can be made to exactly cancel the variation in the gravitational force. Expressed another way, normal buoyancy is exactly countered by a "magnetic buoyancy". To demonstrate the principle, a solution of MnC12 in water has been used. First the variation of the susceptibility of this paramagnetic solution with

  9. Magnetic resonance susceptibility weighted imaging in neurosurgery: current applications and future perspectives.

    PubMed

    Di Ieva, Antonio; Lam, Timothy; Alcaide-Leon, Paula; Bharatha, Aditya; Montanera, Walter; Cusimano, Michael D

    2015-12-01

    Susceptibility weighted imaging (SWI) is a relatively new imaging technique. Its high sensitivity to hemorrhagic components and ability to depict microvasculature by means of susceptibility effects within the veins allow for the accurate detection, grading, and monitoring of brain tumors. This imaging modality can also detect changes in blood flow to monitor stroke recovery and reveal specific subtypes of vascular malformations. In addition, small punctate lesions can be demonstrated with SWI, suggesting diffuse axonal injury, and the location of these lesions can help predict neurological outcome in patients. This imaging technique is also beneficial for applications in functional neurosurgery given its ability to clearly depict and differentiate deep midbrain nuclei and close submillimeter veins, both of which are necessary for presurgical planning of deep brain stimulation. By exploiting the magnetic susceptibilities of substances within the body, such as deoxyhemoglobin, calcium, and iron, SWI can clearly visualize the vasculature and hemorrhagic components even without the use of contrast agents. The high sensitivity of SWI relative to other imaging techniques in showing tumor vasculature and microhemorrhages suggests that it is an effective imaging modality that provides additional information not shown using conventional MRI. Despite SWI's clinical advantages, its implementation in MRI protocols is still far from consistent in clinical usage. To develop a deeper appreciation for SWI, the authors here review the clinical applications in 4 major fields of neurosurgery: neurooncology, vascular neurosurgery, neurotraumatology, and functional neurosurgery. Finally, they address the limitations of and future perspectives on SWI in neurosurgery.

  10. Magnetic Susceptibility of Ancient and Modern Potsherds Using a Fast, Cheap and Portable Probe

    NASA Astrophysics Data System (ADS)

    Glover, P. W.

    2009-05-01

    It has been estimated that there exist over 100 million ancient potsherds in various collections worldwide, many of which have never been studied and for which the provenance is ambiguous or unknown. Indeed, many collections are extremely badly catalogued or completely mixed-up. We have been using a novel portable probe to measure the magnetic susceptibility and electrical conductivity of potsherds in the hope that this fast, cheap and portable measurement can provide data that will help to sort similar looking potsherds into sets in a manner which may help to define their provenance. The probe, which resembles a firearm, uses the Hall effect to make a non-destructive measurement on the potsherd. The probe is attached to an Dell Axim X51 PDA, which runs software that allows the measurement to be carried out and logged. Each measurement, which is made by pressing a button on the gun, takes only a few seconds. We have made measurements on three suites of ancient potsherds as well as a suite of modern potsherds that were created by using a garden centre and a hammer! In each case a set of 5 stacked measurements were taken on the inside and outside faces of the potsherd in two perpendicular directions. Potsherds which were either (i) so flat that the inside and outside could not be distinguished, (ii) so curved (radius of curvature less than 5 cm) that the probe tip could not approach the surface sufficiently closely, or (iii) smaller than the probe tip, were excluded from the suite of measurements. Each suite contained over 50 measureable potsherds. All measurements were completed within one day. In this pilot study we found that (1) each suite was represented by a normal distribution of magnetic susceptibility values, (2) the four different suites could be distinguished statistically on the basis of their magnetic susceptibility measurements, but (3) the distinction was not sufficiently powerful to separate all potsherds (i.e., there was a significant overlap of the

  11. Magnetic susceptibilities of liquid Cr-Au, Mn-Au and Fe-Au alloys

    SciTech Connect

    Ohno, S.; Shimakura, H.; Tahara, S.; Okada, T.

    2015-08-17

    The magnetic susceptibility of liquid Cr-Au, Mn-Au, Fe-Au and Cu-Au alloys was investigated as a function of temperature and composition. Liquid Cr{sub 1-c}Au{sub c} with 0.5 ≤ c and Mn{sub 1-c}Au{sub c} with 0.3≤c obeyed the Curie-Weiss law with regard to their dependence of χ on temperature. The magnetic susceptibilities of liquid Fe-Au alloys also exhibited Curie-Weiss behavior with a reasonable value for the effective number of Bohr magneton. On the Au-rich side, the composition dependence of χ for liquid TM-Au (TM=Cr, Mn, Fe) alloys increased rapidly with increasing TM content, respectively. Additionally, the composition dependences of χ for liquid Cr-Au, Mn-Au, and Fe-Au alloys had maxima at compositions of 50 at% Cr, 70 at% Mn, and 85 at% Fe, respectively. We compared the composition dependences of χ{sub 3d} due to 3d electrons for liquid binary TM-M (M=Au, Al, Si, Sb), and investigated the relationship between χ{sub 3d} and E{sub F} in liquid binary TM-M alloys at a composition of 50 at% TM.

  12. Noncontact technique for measuring the electrical resistivity and magnetic susceptibility of electrostatically levitated materials.

    PubMed

    Rustan, G E; Spyrison, N S; Kreyssig, A; Prozorov, R; Goldman, A I

    2012-10-01

    We describe the development of a new method for measuring the electrical resistivity and magnetic susceptibility of high temperature liquids and solids. The technique combines a tunnel diode oscillator with an electrostatic levitation furnace to perform noncontact measurements on spherical samples 2-3 mm in diameter. The tank circuit of the oscillator is inductively coupled to the sample, and measurements of the oscillator frequency as a function of sample temperature can be translated into changes in the sample's electrical resistivity and magnetic susceptibility. Particular emphasis is given on the need to improve the positional stability of the levitated samples, as well as the need to stabilize the temperature of the measurement coil. To demonstrate the validity of the technique, measurements have been performed on solid spheres of pure zirconium and low-carbon steel. In the case of zirconium, while absolute values of the resistivity were not determined, the temperature dependence of the resistivity was measured over the range of 640-1770 K and found to be in good agreement with literature data. In the case of low-carbon steel, the ferromagnetic-paramagnetic transition was clearly observable and, when combined with thermal data, appears to occur simultaneously with the solid-solid structural transition.

  13. Geophysical monitoring of simulated graves with resistivity, magnetic susceptibility, conductivity and GPR in Colombia, South America.

    PubMed

    Molina, Carlos Martin; Pringle, Jamie K; Saumett, Miguel; Evans, Gethin T

    2016-04-01

    In most Latin American countries there are significant numbers of both missing people and forced disappearances, ∼71,000 Colombia alone. Successful detection of buried human remains by forensic search teams can be difficult in varying terrain and climates. Three clandestine burials were simulated at two different depths commonly encountered in Latin America. In order to gain critical knowledge of optimum geophysical detection techniques, burials were monitored using: ground penetrating radar, magnetic susceptibility, bulk ground conductivity and electrical resistivity up to twenty-two months post-burial. Radar survey results showed good detection of modern 1/2 clothed pig cadavers throughout the survey period on 2D profiles, with the 250MHz antennae judged optimal. Both skeletonised and decapitated and burnt human remains were poorly imaged on 2D profiles with loss in signal continuity observed throughout the survey period. Horizontal radar time slices showed good anomalies observed over targets, but these decreased in amplitude over the post-burial time. These were judged due to detecting disturbed grave soil rather than just the buried targets. Magnetic susceptibility and electrical resistivity were successful at target detection in contrast to bulk ground conductivity surveys which were unsuccessful. Deeper burials were all harder to image than shallower ones. Forensic geophysical surveys should be undertaken at suspected burial sites.

  14. Strain, anisotropy of anhysteretic remanence, and anisotropy of magnetic susceptibility in a slaty tuff

    NASA Astrophysics Data System (ADS)

    Nakamura, Norihiro; Borradaile, Graham J.

    2001-10-01

    Finite strain data for the Borrowdale slaty tuffs compare variably with the anisotropy of magnetic susceptibility (AMS) and anisotropy of anhysteretic remanent magnetization (AARM). Finite strain, determined from lapilli-rims, shows that slaty cleavage was formed by coaxial flattening with X: Y: Z in the ratio 1.74:1.21 and 0.48. AARM was measured in different coercivity windows to isolate contributions from magnetite of different grain sizes: (a) 0-3 mT for multi-domain (MD), (b) 3-15 mT for pseudo-single-domain (PSD) and (c) 15-60 mT for single-domain (SD). AMS combines petrofabric contributions from silicates as well as magnetite. Magnetite grains may grow, recrystalize or rearrange domains after or during metamorphism and postdate or overlap with the silicate's fabric evolution. AMS foliation, defined by paramagnetic chlorites, is parallel to slaty cleavage. AARM foliation for SD magnetites is offset clockwise from AMS foliation, which may reflect late crystallization or domain-rearrangement of magnetites in response to a latter noncoaxial increment. AMS fabric-shape consistently corresponds to strain ellipsoids and indicates that the strain-induced AMS fabric is susceptible to the change of oblateness rather than strain intensity. Furthermore, investigation of the different AARM subfabrics and finite strain shows that only SD magnetite's AARM correlates with finite strain, and weakly at that.

  15. Thermomagnetic behavior of magnetic susceptibility - heating rate and sample size effects

    NASA Astrophysics Data System (ADS)

    Jordanova, Diana; Jordanova, Neli

    2015-12-01

    Thermomagnetic analysis of magnetic susceptibility k(T) was carried out for a number of natural powder materials from soils, baked clay and anthropogenic dust samples using fast (11oC/min) and slow (6.5oC/min) heating rates available in the furnace of Kappabridge KLY2 (Agico). Based on the additional data for mineralogy, grain size and magnetic properties of the studied samples, behaviour of k(T) cycles and the observed differences in the curves for fast and slow heating rate are interpreted in terms of mineralogical transformations and Curie temperatures (Tc). The effect of different sample size is also explored, using large volume and small volume of powder material. It is found that soil samples show enhanced information on mineralogical transformations and appearance of new strongly magnetic phases when using fast heating rate and large sample size. This approach moves the transformation at higher temperature, but enhances the amplitude of the signal of newly created phase. Large sample size gives prevalence of the local micro- environment, created by evolving gases, released during transformations. The example from archeological brick reveals the effect of different sample sizes on the observed Curie temperatures on heating and cooling curves, when the magnetic carrier is substituted magnetite (Mn0.2Fe2.70O4). Large sample size leads to bigger differences in Tcs on heating and cooling, while small sample size results in similar Tcs for both heating rates.

  16. Influence of dipolar interactions on the magnetic susceptibility spectra of ferrofluids

    NASA Astrophysics Data System (ADS)

    Sindt, Julien O.; Camp, Philip J.; Kantorovich, Sofia S.; Elfimova, Ekaterina A.; Ivanov, Alexey O.

    2016-06-01

    The frequency-dependent magnetic susceptibility of a ferrofluid is calculated under the assumption that the constituent particles undergo Brownian relaxation only. Brownian-dynamics simulations are carried out in order to test the predictions of a recent theory [A. O. Ivanov, V. S. Zverev, and S. S. Kantorovich, Soft Matter 12, 3507 (2016), 10.1039/C5SM02679B] that includes the effects of interparticle dipole-dipole interactions. The theory is based on the so-called modified mean-field approach and possesses the following important characteristics: in the low-concentration, noninteracting regime, it gives the correct single-particle Debye-theory results; it yields the exact leading-order results in the zero-frequency limit; it includes particle polydispersity correctly from the outset; and it is based on firm theoretical foundations allowing, in principle, systematic extensions to treat stronger interactions and/or higher concentrations. The theory and simulations are compared in the case of a model monodisperse ferrofluid, where the effects of interactions are predicted to be more pronounced than in a polydisperse ferrofluid. The susceptibility spectra are analyzed in detail in terms of the low-frequency behavior, the position of the peak in the imaginary (out-of-phase) part, and the characteristic decay time of the magnetization autocorrelation function. It is demonstrated that the theory correctly predicts the trends in all of these properties with increasing concentration and dipolar coupling constant, the product of which is proportional to the Langevin susceptibility χL. The theory is in quantitative agreement with the simulation results as long as χL≲1 .

  17. Uncertainty of spatial distributions of soil magnetic susceptibility in areas of different type of land cover and anthropogenic pressure

    NASA Astrophysics Data System (ADS)

    Zawadzki, Jaroslaw; Fabijańczyk, Piotr

    2016-04-01

    There is still a high interest in the improvement of soil magnetometry procedures that would increase its accuracy. Soil magnetometry is usually used as a fast screening method that is used to assess the degree of soil pollution. As the magnetometric measurements do not provide the exact information about the concentration of elements in soil, it is very important to determine the uncertainty of the spatial distributions of soil magnetic susceptibility. The goal of this study was to analyze and present geostatistical methods of assessing the uncertainty of spatial distribution of soil magnetic susceptibility in areas of different land cover and anthropogenic pressure. In particular, spatial distributions of magnetic susceptibility measured on the soil surface using a MS2D Bartington device were calculated using indicator methods that make it possible to calculate the probability of exceeding the critical levels of soil magnetic susceptibility. Measurements were performed in areas located in the Upper Silesian Industrial Area in Poland, and in Norway. In these areas soil magnetic susceptibility was measured on the soil surface using a MS2D Bartington device. Additionally, soil samples were taken in order to perform chemical measurements that included the determination of a concentration of selected elements. Acknowledgment The research leading to these results has received funding from the Polish-Norwegian Research Programme operated by the National Centre for Research and Development underthe Norwegian Financial Mechanism 2009-2014 in the frame of Project IMPACT - Contract No Pol-Nor/199338/45/2013.

  18. Magnetic fabric of selected loess/paleosol sections as studied by AMS, anisotropy of frequency-dependent susceptibility and anisotropy of out-of-phase susceptibility

    NASA Astrophysics Data System (ADS)

    Chadima, M.; Hrouda, F.; Jezek, J.

    2015-12-01

    The preferred orientation of magnetic minerals in loess/paleosol sequencies can be studied through the anisotropy of magnetic susceptibility (AMS), which can be above all employed in the investigation of the dynamics of the eolian deposition including the changes in paleowind directions. In addition, it can be used in the indication of the post-depositional magnetic fabric re-working, or in tracing the magnetic fabric changes during pedogenesis. Recently developed techniques using anisotropy of frequency-dependent susceptibility (fdAMS) and anisotropy of out-of-phase susceptibility (opAMS) can assess the magnetic sub-fabrics of viscous particles on transition between SP and SSD. The width of the particle size interval investigated by the fdAMS is controlled by the operating frequencies used and their differences. In case of opAMS, the interval is always narrower than that in fdAMS and depends also on the operating frequency used. In three loess/paleosol sequences investigated in the Czech Republic, the degrees of AMS, fdAMS, and opAMS are significantly lower in paleosols than in loess horizons. This indicates that the preferred orientation of magnetic particles created during pedogenesis is much weaker than that of the particles deposited during loess formation. In addition, the degrees of fdAMS and opAMS are much higher than that of AMS. This may indicate strong anisotropy of viscous magnetic particles, because the fdAMS and opAMS are primarily controlled by them. The degree of AMS of the whole rock is low due to compensation effects of SP and SSD particles, whose grain anisotropies are anti-coaxial. The principal directions of AMS, fdAMS, and opAMS are mostly roughly co-axial suggesting more or less identical origins of magnetic sub-fabrics according to grain size. Less frequently, the principal directions of fdAMS or opAMS differ from those of AMS probably indicating post-depositional effects on particular grain-size classes. The fdAMS and opAMS show as powerful

  19. Magnetic AC susceptibility study of the cobalt segregation process in melt-spun Cu-Co alloys

    NASA Astrophysics Data System (ADS)

    López, A.; Lázaro, F. J.; von Helmolt, R.; García-Palacios, J. L.; Wecker, J.; Cerva, H.

    1998-08-01

    Temperature and frequency-dependent AC susceptibility has been used to characterize Cu 90Co 10 melt-spun ribbons, about 15 μm thick, in order to see to what extent this technique yields information about the segregation of cobalt in this alloy. The interpretation of the results includes, as a prerequisite, a transmission electron microscopy (TEM) characterization and makes use of previous field-dependent magnetization data on the same samples. Due to their different dynamical magnetic properties, the large intergrain precipitates, the small intragrain aggregates and the remaining Cu-Co solid solution, previously detected in these alloys, are independently observed by AC susceptibility as ferromagnetic, superparamagnetic and spin-glass species. Contrary to other, mostly local, microstructural characterization techniques of use with nanostructured materials, the AC susceptibility yields information about the whole sample. Furthermore, unlike the measurement of the temperature-dependent magnetization which is the magnetic technique mostly used until now, the results are basically independent of the thermal history. The correlation between microstructure and magnetic properties is illustrated by a scheme which includes magnetization, AC susceptibility and TEM data.

  20. Temperature-dependency of Magnetic Susceptibility U Advantages and Limits For Magneto-mineralogical Studies

    NASA Astrophysics Data System (ADS)

    Kontny, A.

    Low-field magnetic susceptibility measurements in the temperature range U192 to 700 C (k(T)) are a widely applied method used for the identification of magnetic phases and characteristic magnetic phase transitions. One of the advantages of this method is the precise determination of titanomagnetite composition independently from grain size. However, the interpretations of k(T)-curves often are discussed controversially because other effects like grain size or the occurrence of more than one magnetic phase complicate the courses. Case studies from the titanomagnetite and titanohe- matite solid solution series including pure magnetite and hematite will be presented and variations in chemical composition, alteration and grain size will be discussed in relation to their geological significance. (1) In subaerially extruded basaltic lava differences in the low-temperature legs of the k(T) curves indicate variations in the degree of high-temperature (deuteric) oxidation of titanomagnetite. This alteration to magnetite-rich titanomagnetite is accompanied by a grain size reduction, which can be correlated with the development of a susceptibility peak at about U160 C. Fur- ther oxidation transforms the titanomagnetite into titanohematite which again results in a characteristic k(T) behavior at low temperatures with a decrease in k with in- creasing temperature (2) Hydrothermal alteration from magnetite to hematite creates a hematite phase that cannot be seen in k(T)-curves. However, hematite that is grown in sediments, can be identified by its Tc. Therefore it is assumed that crystallinity of magnetic phases seems to play a significant role to explain a different behaviour. (3) Submarine basalts rapidly quenched from high temperatures often show wide anti- clines in the k(T)-curves which can be correlated with a range of chemical composition and grain sizes, including small amounts of pure magnetite. This feature is commonly attributed to low-temperature alteration of single

  1. Three-dimensional analysis of magnetic susceptibility in areas with different type of land use

    NASA Astrophysics Data System (ADS)

    Zawadzki, Jarosław; Fabijańczyk, Piotr

    2015-04-01

    The knowledge of the type of semivariance and its parameters such as nugget-effect, range of correlation and sill, that quantitatively characterize spatial variability of a studied environmental phenomenon, can be essential for both measurements planning and analysis of results. In particular this is the truth in the case of magnetometric measurements of soil pollution. Field magnetometry is internationally recognized as valuable, convenient and affordable tool for soil pollution screening and assessment. However, this geophysical method usually requires support of detailed statistical and geostatistical analyses. The goal of this study was to evaluate the parameters of spatial variability of soil magnetic susceptibility depending on the terrain usage. To do so, several types of study area were specially selected: forest, arable field and urban park. Some of the study areas were neighboring to each other, in order to ensure that the anthropogenic pressure was the same at each site. In order to analyze soil magnetic susceptibility in 3-dimensional space, measurements were performed on the soil surface and in soil profile, using the MS2D and MS2C Bartington instruments, respectively. MS2D measurements were performed using quasi-regular grids, and at each sample point 10 single MS2D readings were carried out in the circle with the diameter of about 2 meters. MS2C measurements were performed using soil cores collected in the field, down to the depth of about 30cm. Such approach combines the advantages of both types of measurements and allows to get deeper insight into the distribution of soil pollution. As the first step of the analysis, the semivariances of magnetic susceptibility were calculated and thoroughly modeled for all different forms of land use, on the basis of only the MS2D measurements. Then, the MS2D and MS2C measurements were jointed into one three-dimensional data set, and were used together to calculate and model the semivariances. Finally, the

  2. Magnetic susceptibility and hardness of Au-xPt-yNb alloys for biomedical applications.

    PubMed

    Uyama, Emi; Inui, Shihoko; Hamada, Kenichi; Honda, Eiichi; Asaoka, Kenzo

    2013-09-01

    Metal devices in the human body induce serious metal artifacts in magnetic resonance imaging (MRI). Metals artifacts are mainly caused by a volume magnetic susceptibility (χv) mismatch between a metal device and human tissue. In this research, Au-xPt-yNb alloys were developed for fabricating MRI artifact-free biomedical metal devices. The magnetic properties, hardness and phase constitutions of these alloys were investigated. The Au-xPt-8Nb alloys showed satisfactory χv values. Heat treatments did not clearly change the χv values for Au-xPt-8Nb alloys. The Vickers hardness (HV) of these two alloys was much higher than that of high-Pt alloys; moreover, aging at 700°C increased the HV values of these two alloys. A dual phase structure consisting of face-centered cubic α1 and α2 phases was observed and aging at 700°C promoted phase separation. The Au-5Pt-8Nb and Au-10Pt-8Nb alloys showed satisfactory χv values and high hardness and are thus suggested as candidates for MRI artifact-free alloys for biomedical applications.

  3. A Method for Whole Brain Ex Vivo Magnetic Resonance Imaging with Minimal Susceptibility Artifacts

    PubMed Central

    Shatil, Anwar S.; Matsuda, Kant M.; Figley, Chase R.

    2016-01-01

    Magnetic resonance imaging (MRI) is a non-destructive technique that is capable of localizing pathologies and assessing other anatomical features (e.g., tissue volume, microstructure, and white matter connectivity) in postmortem, ex vivo human brains. However, when brains are removed from the skull and cerebrospinal fluid (i.e., their normal in vivo magnetic environment), air bubbles and air–tissue interfaces typically cause magnetic susceptibility artifacts that severely degrade the quality of ex vivo MRI data. In this report, we describe a relatively simple and cost-effective experimental setup for acquiring artifact-free ex vivo brain images using a clinical MRI system with standard hardware. In particular, we outline the necessary steps, from collecting an ex vivo human brain to the MRI scanner setup, and have also described changing the formalin (as might be necessary in longitudinal postmortem studies). Finally, we share some representative ex vivo MRI images that have been acquired using the proposed setup in order to demonstrate the efficacy of this approach. We hope that this protocol will provide both clinicians and researchers with a straight-forward and cost-effective solution for acquiring ex vivo MRI data from whole postmortem human brains. PMID:27965620

  4. Ac-susceptibility investigations of superspin blocking and freezing in interacting magnetic nanoparticle ensembles

    NASA Astrophysics Data System (ADS)

    Botez, Cristian E.; Morris, Joshua L.

    2016-03-01

    We have investigated the effect of dipolar interactions on the superspin blocking and freezing of 9 nm average size Fe3O4 magnetic nanoparticle ensembles. Our dynamic susceptibility data reveals a two-regime behavior of the blocking temperature, T B, upon diluting a Fe3O4/hexane magnetic fluid. As the nanoparticle volume ratio, Φ, is reduced from an as-prepared reference Φ = 1 to Φ = 1/96, the blocking temperature decreases from 46.1 K to 34.2 K, but higher values reenter upon further diluting the magnetic fluid to Φ = 1/384 (where T B = 42.5 K). We found evidence that cooling below T B within the higher concentration range (Φ > 1/48) leads to the collective freezing of the superspins, whereas individual superspin blocking occurs in the presence of weaker interactions (Φ < 1/96). The unexpected increase of the blocking temperature with the decrease of the inter-particle interactions observed at low nanoparticle concentrations is well described by the Mørup-Tronc model.

  5. Low temperature magnetic susceptibility behavior of the Neuschwanstein EL6 meteorite and mineral daubreelite (FeCr2S4)

    NASA Astrophysics Data System (ADS)

    Kohout, T.; Kletetschka, G.; Lehtinen, M.; Pesonen, L. J.; Wasilewski, P. J.

    2006-12-01

    Neuschwanstein meteorite (enstatite chondrite EL-6) fall occurred on April 6, 2002 close to Neuschwanstein castle in Bavaria, Germany. Total three meteorite bodies were found on the fall site. Two fragments coming from a 1750g body found on July 14, 2002 were obtained to the Division of Geophysics, University of Helsinki. The low temperature magnetic properties were investigated using KLY-3 and KLY-4 kappabridges equipped with low temperature control unit. During the low-temperature susceptibility measurements an unknown kink feature was observed at ~150 K on all measured samples. The closest known magnetic transition is the curie temperature Tc ~170 K of synthetic FeCr2S4 mentioned in Müller et al., 2006. FeCr2S4 is naturally present in enstatite chondrites and iron meteorites in the form of mineral daubreelite and was reported to be present in the Neuschwanstein meteorite in Zipfel and Dreibus, 2003. The extensive study of magnetic susceptibility of Neuschwanstein meteorite and daubreelite extract form Coahuila iron meteorite (hexahedrite, II A) was conducted in order to investigate the low temperature magnetic susceptibility of those materials and its field and frequency dependence. The results indicate Tc of natural daubreelite extract from Coahuila meteorite to be ~160 K what is slightly lower than the Tc of synthetic FeCr2S4 reported in Müller et al., 2006. The magnetic susceptibility of natural daubreelite from Coahuila meteorite and of ~150 K feature in Neuschwanstein meteorite show no field dependence of magnetic susceptibility. Due to the similarity in the low temperature magnetic susceptibility behaviour of Neuschwanstein meteorite and daubreelite extract from Coahuila meteorite we link the Neuschwanstein ~150 K feature to the Tc of daubreelite present in this meteorite. The 10 K difference of the Tc of daubreelite in Neuschwanstein and Coahuila meteorites can be attributed to the presence of impurities or structural deformations in the daubreelite

  6. Generalised Eisenhart lift of the Toda chain

    SciTech Connect

    Cariglia, Marco; Gibbons, Gary

    2014-02-15

    The Toda chain of nearest neighbour interacting particles on a line can be described both in terms of geodesic motion on a manifold with one extra dimension, the Eisenhart lift, or in terms of geodesic motion in a symmetric space with several extra dimensions. We examine the relationship between these two realisations and discover that the symmetric space is a generalised, multi-particle Eisenhart lift of the original problem that reduces to the standard Eisenhart lift. Such generalised Eisenhart lift acts as an inverse Kaluza-Klein reduction, promoting coupling constants to momenta in higher dimension. In particular, isometries of the generalised lift metric correspond to energy preserving transformations that mix coordinates and coupling constants. A by-product of the analysis is that the lift of the Toda Lax pair can be used to construct higher rank Killing tensors for both the standard and generalised lift metrics.

  7. Effect of electron-electron interaction on the magnetic moment and susceptibility of a parabolic GaAs quantum dot

    NASA Astrophysics Data System (ADS)

    Boda, Aalu; Kumar, D. Sanjeev; Sankar, I. V.; Chatterjee, Ashok

    2016-11-01

    The problem of a parabolically confined two-dimensional semiconductor GaAs quantum dot with two interacting electrons in the presence of an external magnetic field and the spin-Zeeman interaction is studied using a method of numerical diagonalization. The energy spectrum is calculated as a function of the magnetic field. The magnetic moment (M) and the magnetic susceptibility (χ) show zero temperature diamagnetic peaks due to the exchange induced singlet-triplet transitions. The position and the number of these peaks depend both on the confinement strength of the quantum dot and the strength of the electron-electron interaction (β) .

  8. Magnetic susceptibility measurements on ancient and modern potsherds using a fast, cheap and portable probe

    NASA Astrophysics Data System (ADS)

    Glover, P. W. J.

    2009-04-01

    It has been estimated that there exist over 100 million ancient potsherds in various collections worldwide, many of which have never been studied and for which the provenance is ambiguous or unknown. Indeed, many collections are extremely badly catalogued or completely mixed-up. We have been using a novel portable probe to measure the magnetic susceptibility and electrical conductivity of potsherds in the hope that this fast, cheap and portable measurement can provide data that will help to sort similar looking potsherds into sets in a manner which may help to define their provenance. The probe, which resembles a firearm, uses the Hall effect to make a non-destructive measurement on the potsherd. The probe is attached to an Dell Axim X51 PDA, which runs software that allows the measurement to be carried out and logged. Each measurement, which is made by pressing a button on the gun, takes only a few seconds. We have made measurements on three suites of ancient potsherds as well as a suite of modern potsherds that were created by using a garden centre and a hammer! In each case a set of 5 stacked measurements were taken on the inside and outside faces of the potsherd in two perpendicular directions. Potsherds which were either (i) so flat that the inside and outside could not be distinguished, (ii) so curved (radius of curvature less than 5 cm) that the probe tip could not approach the surface sufficiently closely, or (iii) smaller than the probe tip, were excluded from the suite of measurements. Each suite contained over 50 measureable potsherds. All measurements were completed within one day. In this pilot study we found that (1) each suite was represented by a normal distribution of magnestic susceptibility values, (2) the four different suites could be distinguished statistically on the basis of their magnetic susceptibilty measurements, but (3) the distinction was not sufficiently powerful to separate all potsherds (i.e., there was a significant overlap of the

  9. Magnetism in Complex Oxides Probed by Magnetocaloric Effect and Transverse Susceptibility

    NASA Astrophysics Data System (ADS)

    Bingham, Nicholas S.

    Magnetic oxides exhibit rich complexity in their fundamental physical properties determined by the intricate interplay between structural, electronic and magnetic degrees of freedom. The common themes that are often present in these systems are the phase coexistence, strong magnetostructural coupling, and possible spin frustration induced by lattice geometry. While a complete understanding of the ground state magnetic properties and cooperative phenomena in this class of compounds is key to manipulating their functionality for applications, it remains among the most challenging problems facing condensed-matter physics today. To address these outstanding issues, it is essential to employ experimental methods that allow for detailed investigations of the temperature and magnetic field response of the different phases. In this PhD dissertation, I will demonstrate the relatively unconventional experimental methods of magnetocaloric effect (MCE) and radio-frequency transverse susceptibility (TS) as powerful probes of multiple magnetic transitions, glassy phenomena, and ground state magnetic properties in a large class of complex magnetic oxides, including La0.7Ca0.3- xSrxMnO3 (x = 0, 0.05, 0.1, 0.2 and 0.25), Pr0.5Sr0.5MnO3, Pr1-xSrxCoO 3 (x = 0.3, 0.35, 0.4 and 0.5), La5/8- xPrxCa3/8MnO3 (x = 0.275 and 0.375), and Ca3Co2O 6. First, the influences of strain and grain boundaries, via chemical substitution and reduced dimensionality, were studied via MCE in La0.7Ca 0.3-xSrxMnO 3. Polycrystalline, single crystalline, and thin-film La0.7Ca 0.3-xSrxMnO 3 samples show a paramagnetic to ferromagnetic transition at a wide variety of temperatures as well as an observed change in the fundamental nature of the transition (i.e. first-order magnetic transition to second order magnetic transition) that is dependent on the chemical concentration and dimensionality. Systematic TS and MCE experiments on Pr0.5Sr0.5MnO 3 and Pr0.5Sr0.5CoO3 have uncovered the different nature of low

  10. Electronic heat capacity and magnetic susceptibility of ferromagnetic silicene sheet under strain

    NASA Astrophysics Data System (ADS)

    Yarmohammadi, Mohsen

    2017-01-01

    The electronic heat capacity (EHC) and magnetic susceptibility (MS) of the two-dimensional material ferromagnetic graphene's silicon analog, silicene, are investigated by the strain-induced and the applied electric field within the Green's function technique and the Kane-Mele Hamiltonian. Dirac cone approximation has been performed to investigate the system under strain along the zigzag (ZZ) direction. The main attention is focused on the effects of external static electric field in the presence of strain on EHC and MS of a ferromagnetic silicene sheet. In the presence of strain, carriers have a larger effective mass and transport decreases. As a result, the temperature dependence of EHC and MS gives a critical strain around 10%. Furthermore, electric field breaks the reflection symmetry of the structure and a transition to the topological insulator for strained ferromagnetic silicene has occurred when the electric field is increased. In this phase, EHC and MS have weird behaviors with temperature.

  11. Magnetic susceptibility as a proxy for investigating microbially mediated iron reduction

    USGS Publications Warehouse

    Mewafy, F.M.; Atekwana, E.A.; Werkema, D.D.; Slater, L.D.; Ntarlagiannis, D.; Revil, A.; Skold, M.; Delin, G.N.

    2011-01-01

    We investigated magnetic susceptibility (MS) variations in hydrocarbon contaminated sediments. Our objective was to determine if MS can be used as an intrinsic bioremediation indicator due to the activity of iron-reducing bacteria. A contaminated and an uncontaminated core were retrieved from a site contaminated with crude oil near Bemidji, Minnesota and subsampled for MS measurements. The contaminated core revealed enriched MS zones within the hydrocarbon smear zone, which is related to iron-reduction coupled to oxidation of hydrocarbon compounds and the vadose zone, which is coincident with a zone of methane depletion suggesting aerobic or anaerobic oxidation of methane is coupled to iron-reduction. The latter has significant implications for methane cycling. We conclude that MS can serve as a proxy for intrinsic bioremediation due to the activity of iron-reducing bacteria iron-reducing bacteria and for the application of geophysics to iron cycling studies. ?? 2011 by the American Geophysical Union.

  12. Magnetic susceptibility as a proxy for investigating microbially mediated iron reduction

    NASA Astrophysics Data System (ADS)

    Mewafy, Farag M.; Atekwana, Estella A.; Werkema, D. Dale, Jr.; Slater, Lee D.; Ntarlagiannis, Dimitrios; Revil, André; Skold, Magnus; Delin, Geoffrey N.

    2011-11-01

    We investigated magnetic susceptibility (MS) variations in hydrocarbon contaminated sediments. Our objective was to determine if MS can be used as an intrinsic bioremediation indicator due to the activity of iron-reducing bacteria. A contaminated and an uncontaminated core were retrieved from a site contaminated with crude oil near Bemidji, Minnesota and subsampled for MS measurements. The contaminated core revealed enriched MS zones within the hydrocarbon smear zone, which is related to iron-reduction coupled to oxidation of hydrocarbon compounds and the vadose zone, which is coincident with a zone of methane depletion suggesting aerobic or anaerobic oxidation of methane is coupled to iron-reduction. The latter has significant implications for methane cycling. We conclude that MS can serve as a proxy for intrinsic bioremediation due to the activity of iron-reducing bacteria iron-reducing bacteria and for the application of geophysics to iron cycling studies.

  13. Magnetic susceptibility and heat capacity of graphene in two-band Harrison model

    NASA Astrophysics Data System (ADS)

    Mousavi, Hamze; Bagheri, Mehran; Khodadadi, Jabbar

    2015-11-01

    Using a two-band tight-binding Harrison model and Green's function technique, the influences of both localized σ and delocalized π electrons on the density of states, the Pauli paramagnetic susceptibility, and the heat capacity of a graphene sheet are investigated. We witness an extension in the bandwidth and an increase in the number of Van-Hove singularities as well. As a notable point, besides the magnetic nature which includes diamagnetism in graphene-based nanosystems, a paramagnetic behavior associated with the itinerant π electrons could be occurred. Further, we report a Schottky anomaly in the heat capacity. This study asserts that the contribution of both σ and π electrons play dominant roles in the mentioned physical quantities.

  14. Magnetic susceptibility data for some exposed bedrock in the western conterminous United States

    USGS Publications Warehouse

    Gettings, Mark E.; Bultman, Mark W.

    2014-01-01

    In-place rock magnetic susceptibility measurements for 746 sites in the western conterminous United States are reported in a database. Of these 746 sites, 408 sites are in the Silverton Caldera area of the San Juan Mountains of southwestern Colorado. Of the 408 sites in the Silverton Caldera area, 106 sites are underground. The remaining 338 sites outside the Silverton Caldera area were on outcropping rock, are distributed from southern Arizona to northwestern Wyoming, and include data from California, Nevada, Utah, Colorado, and New Mexico. Rock-density measurements are included for some sites. These data have been collected by various U.S. Geological Survey studies from 1991 through 2012 and are intended to help improve geophysical modeling of the Earth’s crust in the Western United States. A map-based graphical user interface is included to facilitate use of the data.

  15. Noncontact technique for measuring the electrical resistivity and magnetic susceptibility of electrostatically levitated melts

    NASA Astrophysics Data System (ADS)

    Rustan, G. E.; Spyrison, N. S.; Kreyssig, A.; Prozorov, R.; Goldman, A. I.

    2012-02-01

    Over the last two decades the popularity of levitation methods for studying equilibrium and supercooled melts has increased steadily. Measurements of density, viscosity, surface tension, and atomic structure have become well established. In contrast, measurements of electrical resistivity and magnetic susceptibility of levitated melts have been very limited. To fill this void, we have combined the tunnel diode oscillator (TDO) technique with electrostatic levitation (ESL) to perform inductively coupled measurements on levitated melts. A description of the basic operating principles of the TDO and ESL will be given, as well as a description of the implementation and performance characteristics of this technique. Preliminary measurements of electrical resistivity in the solid and liquid state will be presented for samples of Zr, Si, and Ge, as well as the measurements of ferromagnetic transitions in Fe and Co based alloys.

  16. Automated Generalisation Within NMAs in 2016

    NASA Astrophysics Data System (ADS)

    Stoter, Jantien; van Altena, Vincent; Post, Marc; Burghardt, Dirk; Duchêne, Cecile

    2016-06-01

    Producing maps and geo-data at different scales is traditionally one of the main tasks of National (and regional) Mapping Agencies (NMAs). The derivation of low-scale maps (i.e. with less detail) from large-scale maps (with more detail), i.e. generalisation, used to be a manual task of cartographers. With the need for more up-to-date data as well as the development of automated generalisation solutions in both research and industry, NMAs are implementing automated generalisation production lines. To exchange experiences and identify remaining issues, a workshop was organised end 2015 by the Commission on Generalisation and Multirepresentation of the International Cartographic Association and the Commission on Modelling and Processing of the European Spatial Data Research. This paper reports about the workshop outcomes. It shows that, most NMAs have implemented a certain form of automation in their workflows, varying from generalisation of certain features while still maintaining a manual workflow; semiautomated editing and generalisation to a fully automated procedure.

  17. Preparation, Magnetic Susceptibility, and Specific Heat on Interlanthanide Perovskites {ital AB}O

    SciTech Connect

    Ito, Kentaro; Tezuka, Keitaro; Hinatsu, Yukio

    2001-02-15

    The interlanthanide perovskites LaHoO{sub 3}, LaErO{sub 3}, LaTmO{sub 3}, LaYbO{sub 3}, LaLuO{sub 3}, CeTmO{sub 3}, CeYbO{sub 3}, CeLuO{sub 3}, PrYbO{sub 3}, and PrLuO{sub 3} were prepared by the coprecipitation method. Their magnetic susceptibility measurements were carried out in the temperature range between 1.8 and 300 K, and it was found that LaYbO{sub 3}, CeYbO{sub 3}, and PrYbO{sub 3} had antiferromagnetic ordering with a weak ferromagnetism at 2.7 K. LaErO{sub 3} also showed antiferromagnetic ordering at 2.4 K. Specific heat measurements for LaErO{sub 3} and LaYbO{sub 3} showed the {lambda}-type anomaly at 2.4 and 2.7 K, respectively, which is in good agreement with the susceptibility measurements.

  18. Iron core formation in horse spleen ferritin: magnetic susceptibility, pH, and compositional studies.

    PubMed

    Hilty, S; Webb, B; Frankel, R B; Watt, G D

    1994-11-15

    Horse spleen ferritin (HoSF) reconstituted with small iron cores ranging in size from 8 to 500 iron atoms was studied by magnetic susceptibility and pH measurements to determine when the added Fe3+ begins to aggregate and form antiferromagnetically coupled clusters and also to determine the hydrolytic state of the iron at low iron loading. The Evans NMR magnetic susceptibility measurements showed that at iron loadings as low as 8 Fe3+/HoSF, at least half of the added iron atoms were involved in antiferromagnetic exchange interactions and the other half were present as isolated iron atoms with S = 5/2. As the core size increased to about 24 iron atoms, the antiferromagnetic exchange interactions among the iron atoms increased until reaching the limiting value of 3.8 Bohr magnetons per iron atom, the value present in holo HoSF. HoSF containing eight or more Fe3+ to which eight Fe2+ were added showed that the Fe2+ ions were at sites remote from the Fe3+ and that the resulting HoSF consisted of individual, noninteracting Fe2+ and the partially aggregated Fe3+. pH measurements for core reduction showed that Fe(OH)3 was initially present at all iron loadings but that in the absence of iron chelators the reduced iron core is partially hydrolyzed. Proton induced x-ray emission spectroscopy showed that Cl- is transported into the iron core during reduction, forming a stable chlorohydroxy Fe(II) mineral phase.

  19. Diffeomorphic susceptibility artifact correction of diffusion-weighted magnetic resonance images

    NASA Astrophysics Data System (ADS)

    Ruthotto, L.; Kugel, H.; Olesch, J.; Fischer, B.; Modersitzki, J.; Burger, M.; Wolters, C. H.

    2012-09-01

    Diffusion-weighted magnetic resonance imaging is a key investigation technique in modern neuroscience. In clinical settings, diffusion-weighted imaging and its extension to diffusion tensor imaging (DTI) are usually performed applying the technique of echo-planar imaging (EPI). EPI is the commonly available ultrafast acquisition technique for single-shot acquisition with spatial encoding in a Cartesian system. A drawback of these sequences is their high sensitivity against small perturbations of the magnetic field, caused, e.g., by differences in magnetic susceptibility of soft tissue, bone and air. The resulting magnetic field inhomogeneities thus cause geometrical distortions and intensity modulations in diffusion-weighted images. This complicates the fusion with anatomical T1- or T2-weighted MR images obtained with conventional spin- or gradient-echo images and negligible distortion. In order to limit the degradation of diffusion-weighted MR data, we present here a variational approach based on a reference scan pair with reversed polarity of the phase- and frequency-encoding gradients and hence reversed distortion. The key novelty is a tailored nonlinear regularization functional to obtain smooth and diffeomorphic transformations. We incorporate the physical distortion model into a variational image registration framework and derive an accurate and fast correction algorithm. We evaluate the applicability of our approach to distorted DTI brain scans of six healthy volunteers. For all datasets, the automatic correction algorithm considerably reduced the image degradation. We show that, after correction, fusion with T1- or T2-weighted images can be obtained by a simple rigid registration. Furthermore, we demonstrate the improvement due to the novel regularization scheme. Most importantly, we show that it provides meaningful, i.e. diffeomorphic, geometric transformations, independent of the actual choice of the regularization parameters.

  20. Effect of Low-Frequency AC Magnetic Susceptibility and Magnetic Properties of CoFeB/MgO/CoFeB Magnetic Tunnel Junctions

    PubMed Central

    Chen, Yuan-Tsung; Lin, Sung-Hao; Sheu, Tzer-Shin

    2014-01-01

    In this investigation, the low-frequency alternate-current (AC) magnetic susceptibility (χac) and hysteresis loop of various MgO thickness in CoFeB/MgO/CoFeB magnetic tunneling junction (MTJ) determined coercivity (Hc) and magnetization (Ms) and correlated that with χac maxima. The multilayer films were sputtered onto glass substrates and the thickness of intermediate barrier MgO layer was varied from 6 to 15 Å. An experiment was also performed to examine the variation of the highest χac and maximum phase angle (θmax) at the optimal resonance frequency (fres), at which the spin sensitivity is maximal. The results reveal that χac falls as the frequency increases due to the relationship between magnetization and thickness of the barrier layer. The maximum χac is at 10 Hz that is related to the maximal spin sensitivity and that this corresponds to a MgO layer of 11 Å. This result also suggests that the spin sensitivity is related to both highest χac and maximum phase angle. The corresponding maximum of χac is related to high exchange coupling. High coercivity and saturation magnetization contribute to high exchange-coupling χac strength.

  1. Skill Generalisation in Teaching Spelling to Children with Learning Difficulties

    ERIC Educational Resources Information Center

    Kohnen, Saskia; Nickels, Lyndsey; Coltheart, Max

    2010-01-01

    A central focus in remedial teaching is the generalisation of responses to contexts in which a student has never been explicitly instructed. Remarkably little is known about how and when generalisation occurs. In this article we examine generalisation effects in the context of spelling. Three areas are discussed: generalisation between spelling…

  2. Nonlinear susceptibility of a quantum spin glass under uniform transverse and random longitudinal magnetic fields

    NASA Astrophysics Data System (ADS)

    Magalhaes, S. G.; Morais, C. V.; Zimmer, F. M.; Lazo, M. J.; Nobre, F. D.

    2017-02-01

    The interplay between quantum fluctuations and disorder is investigated in a quantum spin-glass model, in the presence of a uniform transverse field Γ , as well as of a longitudinal random field hi, which follows a Gaussian distribution characterized by a width proportional to Δ . The interactions are infinite-ranged, and the model is studied through the replica formalism, within a one-step replica-symmetry-breaking procedure; in addition, the dependence of the Almeida-Thouless eigenvalue λAT (replicon) on the applied fields is analyzed. This study is motivated by experimental investigations on the LiHoxY1 -xF4 compound, where the application of a transverse magnetic field yields rather intriguing effects, particularly related to the behavior of the nonlinear magnetic susceptibility χ3, which have led to a considerable experimental and theoretical debate. We have analyzed two physically distinct situations, namely, Δ and Γ considered as independent, as well as these two quantities related, as proposed recently by some authors. In both cases, a spin-glass phase transition is found at a temperature Tf, with such phase being characterized by a nontrivial ergodicity breaking; moreover, Tf decreases by increasing Γ towards a quantum critical point at zero temperature. The situation where Δ and Γ are related [Δ ≡Δ (Γ )] appears to reproduce better the experimental observations on the LiHoxY1 -xF4 compound, with the theoretical results coinciding qualitatively with measurements of the nonlinear susceptibility χ3. In this later case, by increasing Γ gradually, χ3 becomes progressively rounded, presenting a maximum at a temperature T* (T*>Tf ), with both the amplitude of the maximum and the value of T* decreasing gradually. Moreover, we also show that the random field is the main responsible for the smearing of the nonlinear susceptibility, acting significantly inside the paramagnetic phase, leading to two regimes delimited by the temperature T*, one for Tf

  3. The initial magnetic susceptibility of polydisperse ferrofluids: A comparison between experiment and theory over a wide range of concentration

    NASA Astrophysics Data System (ADS)

    Solovyova, Anna Y.; Goldina, Olga A.; Ivanov, Alexey O.; Lebedev, Aleksandr V.; Elfimova, Ekaterina A.

    2016-08-01

    Temperature dependencies of the static initial magnetic susceptibility for ferrofluids at various concentrations are studied using experiment and statistical-mechanical theories. Magnetic susceptibility measurements are carried out for twelve samples of magnetite-based fluids stabilized with oleic acid over a wide range of temperatures (210 K ≲T ≲ 390 K); all samples have the same granulometric composition but different volume ferroparticle concentrations (0.2 ≲ φ ≲ 0.5). Experimental results are analyzed using three theories: the second-order modified mean-field theory (MMF2) [A. O. Ivanov and O. B. Kuznetsova, Phys. Rev. E 64, 41405 (2001)]; its correction for polydisperse ferrofluids arising from Mayer-type cluster expansion and taking into account the first terms of the polydisperse second virial coefficient [A. O. Ivanov and E. A. Elfimova, J. Magn. Magn. Mater 374, 327 (2015)]; and a new theory based on MMF2 combined with the first terms of the polydisperse second and third virial contributions to susceptibility. It turns out that the applicability of each theory depends on the experimental sample density. If twelve ferrofluid samples are split into three groups of strong, moderate, and low concentrated fluids, the temperature dependences of the initial magnetic susceptibility in each group are very precisely described by one of the three theories mentioned above. The determination of a universal formula predicting a ferrofluid susceptibility over a broad range of concentrations and temperatures remains as a challenge.

  4. Petrophysical Characterization of Stony Meteorites Using Low Field Magnetic Susceptibility: Initial Results From Anisotropy Measurements

    NASA Astrophysics Data System (ADS)

    Smith, D. L.; Ernst, R. E.; Herd, R. K.; Claire, S.

    2004-05-01

    Low field magnetic susceptibility represents a fast, systematic and non-destructive technique of meteorite classification [1-4]. We previously reported measurements of bulk susceptibility, and its frequency dependence, along with a `proxy' measure of anisotropy, on 204 specimens from 108 different meteorites in the National Meteorite Collection of Canada [5,6]. Measurements were performed on a Sapphire Instruments Model 2B. Bulk susceptibility values followed expected trends, governed by metal content, with values increasing from LL, to L, to H, to E chondrites. Frequency dependence (19000 vs 825 Hz) was greatest in H and C chondrites. Aubrites (AUB) and Howardites (HOW) had the lowest. Anisotropy of magnetic susceptibility (AMS) was measured using a `proxy' approach: the mean value determined from a series of random sample orientations was compared with repeated measurements in one orientation. AUB, E chondrites and Martian SNCs had the largest inferred anisotropies, while LL and C chondrites had the lowest. Here we report initial results from a follow-up study. Quantitative measurements of the AMS were made on 67 stony meteorite specimens. AMS measurements [3,5,6,7,8,9] can provide information on the physical fabric of the meteorite, and may relate to its deformational history. Samples measured show significant degrees of anisotropy ranging from 1-50 % for an individual specimen (in parentheses is the number of specimens used in the class mean): AUB (5), Acapulcoites (1) and E chondrites (10) display the largest degrees of anisotropy, 40±11 (1 standard deviation), 34, and 24±10, respectively. These classes are followed by Diogenite (1) 20, H (13) 14±7 and L (10) 13±6 chondrites, Brachinite (1) 11, Ureilite (2) 8, Eucrite (4) 7±4, C chondrites (14) 6±3, and Rumurutiite (1) 4. These results match a similar trend based on the `proxy' method [5,6]: AUB and E chondrites were found to have the highest inferred anisotropies followed by tightly grouped H and L

  5. A comparative quantitative analysis of magnetic susceptibility artifacts in echo planar and PROPELLER diffusion-weighted images

    NASA Astrophysics Data System (ADS)

    Cho, Jae-Hwan; Lee, Hae-Kag; Yang, Han-Joon; Lee, Gui-Won; Park, Yong-Soon; Chung, Woon-Kwan

    2013-01-01

    In this study, the authors investigated whether periodically-rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) diffusion-weighted imaging (DWI) can remove magnetic susceptibility artifacts and compared apparent diffusion coefficient (ADC) values for PROPELLER DWI and the common echo planar (EP) DWI. Twenty patients that underwent brain MRI with a metal dental implant were selected. A 3.0T MR scanner was then used to obtain EP DWI, PROPELLER DWI, and corresponding apparent diffusion coefficient (ADC) maps for a b-value of 0 and 1,000 s/mm2. The frequencies of magnetic susceptibility artifacts in four parts of the brain (bilateral temporal lobes, pons, and orbit) were selected. In the ADC maps, we measured the ADC values of both sides of the temporal lobe and the pons. According to the study results, the frequency of magnetic susceptibility artifacts in PROPELLER DW images was lower than it was in EP DW images. In ADC maps, the ADC values of the bilateral temporal lobes and the pons were all higher in PROPELLER ADC maps than in EP ADC maps. Our findings show that when a high-field MRI machine is used, magnetic susceptibility artifacts can distort anatomical structures and produce high-intensity signals. Furthermore, our findings suggest that in many cases, PROPELLER DWI would be helpful in terms of achieving a correct diagnosis.

  6. Anisotropy of magnetic susceptibility of Eolian sediments in Altun Shan: implications for Altyn Tagh Fault tectonics since Pleistocene

    NASA Astrophysics Data System (ADS)

    Zhang, R.

    2015-12-01

    Ancient windblown (eolian) dust, such as in Chinese Loess Plateau (CLP), are treasured for understanding the evolution of aridity and influence by Plateau(mountain)uplift on climate change. Anisotropy of magnetic susceptibility (AMS) is an effective tool in tracking atmospheric direction under weak to moderate speed currents to reconstruct the paleomonsoon model was studied in recent years. Whilst it is sometimes directly or indirectly associated with the effects of tectonic process and developed as a results of burial diagenesis process for these eolian sediments. Here we firstly investigated AMS in a Red clay sequence (eolian deposits during Miocene to Pliocene) accumulated in the margin of Altun Mountains, which has the similar mineral content as that in CLP. The average north-west orientations of minimum magnetic susceptibility (Kmin) axes is tilting towards the active Althy Tagh Fault direction and the average direction of intermediate magnetic susceptibility (Kint) axes is close to be vertical and compacted by the gravity as a second force. The average maximum magnetic susceptibility (Kmax) is perpendicular to either tectonic or gravity directions. Considering there is no obvious metamorphic effects and plastic deformation of particles, we attribute these two stresses determined the transition of petrofabrics from the deposition to tectonics, by the intensified Pleistocene activity of Altyn Tagh Fault.

  7. Using magnetic susceptibility to discriminate between soil moisture regimes in selected loess and loess-like soils in northern Iran

    NASA Astrophysics Data System (ADS)

    Valaee, Morteza; Ayoubi, Shamsollah; Khormali, Farhad; Lu, Sheng Gao; Karimzadeh, Hamid Reza

    2016-04-01

    This study used discriminant analysis to determine the efficacy of magnetic measures for discriminating between four soil moisture regimes in northern Iran. The study area was located on loess deposits and loess-like soils containing similar parent material. Four soil moisture regimes including aridic, xeric, udic, and aquic were selected. A total of 25 soil profiles were drug from each regime and composite soil samples were collected within the moisture control section. A set of magnetic measures including magnetic susceptibility at low (χlf) and high (χhf) frequencies, frequency-dependent magnetic susceptibility (χfd), saturation isothermal remnant magnetization (SIRM), and isothermal remnant magnetization (IRM100 mT, IRM 20 mT) were measured in the laboratory. Dithionite citrate bicarbonate (Fed) and acid oxalate (Feo) contents of all soil samples were also determined. The lowest and highest χlf and χhf were observed in aquic and udic moisture regimes, respectively. A similar trend was obtained for Fed and Fed-Feo. The significant positive correlation between Fed and SIRM (r = 0.60; P < 0.01) suggested the formation of stable single domains (SSD) due to pedogenic processes. The results of discriminant analysis indicated that a combination of magnetic measures could successfully discriminate between the selected moisture regimes in the study area (average accuracy = 80%). It can thus be concluded that magnetic measures could be applied as a powerful indicator for differentiation of soil moisture regimes in the study area.

  8. Asteroid impact vs. Deccan eruptions: The origin of low magnetic susceptibility beds below the Cretaceous-Paleogene boundary revisited

    NASA Astrophysics Data System (ADS)

    Abrajevitch, Alexandra; Font, Eric; Florindo, Fabio; Roberts, Andrew P.

    2015-11-01

    The respective roles of an asteroid impact and Deccan Traps eruptions in biotic changes at the Cretaceous-Paleogene (K-Pg) boundary are still debated. In many shallow marine sediments from around the world, the K-Pg boundary is marked by a distinct clay layer that is often underlain by a several decimeter-thick low susceptibility zone. A previous study of the Gubbio section, Italy (Lowrie et al., 1990), attributed low magnetization intensity in this interval to post-depositional dissolution of ferrimagnetic minerals. Dissolution was thought to be a consequence of downward infiltration of reducing waters that resulted from rapid accumulation of organic matter produced by mass extinctions after the K-Pg event. We compare the magnetic properties of sediments from the Gubbio section with those of the Bidart section in southern France. The two sections are similar in their carbonate lithology and the presence of a boundary clay and low susceptibility zone. When compared to background Cretaceous sediments, the low susceptibility zone in both sections is marked by an absence of biogenic magnetite, a decrease in total ferrimagnetic mineral content, and a preferential loss of magnetite with respect to hematite - features that are consistent with reductive dissolution. However, unlike the Gubbio section, where the low susceptibility zone starts immediately below the boundary clay, the low susceptibility zone and the clay layer at Bidart are separated by a ∼4-cm carbonate interval that contains abundant biogenic magnetite. Such separation casts doubt on a causal link between the impact and sediment bleaching. More likely, the low susceptibility layer marks a different environmental event that preceded the impact. An episode of increased atmospheric and oceanic acidity associated with Deccan Traps volcanism that occurred well before the K-Pg impact is argued here to account for the distinct magnetic properties of the low susceptibility intervals.

  9. Soil magnetic susceptibility reflects soil moisture regimes and the adaptability of tree species to these regimes

    USGS Publications Warehouse

    Wang, J.-S.; Grimley, D.A.; Xu, C.; Dawson, J.O.

    2008-01-01

    Flooded, saturated or poorly drained soils are frequently anaerobic, leading to dissolution of the strongly magnetic minerals, magnetite and maghemite, and a corresponding decrease in soil magnetic susceptibility (MS). In this study of five temperate deciduous forests in east-central Illinois, USA, mean surface soil MS was significantly higher adjacent to upland tree species (31 ?? 10-5 SI) than adjacent to floodplain or lowland tree species (17 ?? 10-5 SI), when comparing regional soils with similar parent material of loessal silt. Although the sites differ in average soil MS for each tree species, the relative order of soil MS means for associated tree species at different locations is similar. Lowland tree species, Celtis occidentalis L., Ulmus americana L., Acer saccharinum L., Carya laciniosa (Michx. f.) Loud., and Fraxinus pennsylvanica Marsh. were associated with the lowest measured soil MS mean values overall and at each site. Tree species' flood tolerance rankings increased significantly, as soil MS values declined, the published rankings having significant correlations with soil MS values for the same species groups. The three published classifications of tree species' flood tolerance were significantly correlated with associated soil MS values at all sites, but most strongly at Allerton Park, the site with the widest range of soil drainage classes and MS values. Using soil MS measurements in forests with soil parent material containing similar initial levels of strongly magnetic minerals can provide a simple, rapid and quantitative method to classify soils according to hydric regimes, including dry conditions, and associated plant composition. Soil MS values thus have the capacity to quantify the continuum of hydric tolerances of tree species and guide tree species selection for reforestation. ?? 2007 Elsevier B.V. All rights reserved.

  10. Constraints on deformation of the Southern Andes since the Cretaceous from anisotropy of magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Maffione, Marco; Hernandez-Moreno, Catalina; Ghiglione, Matias C.; Speranza, Fabio; van Hinsbergen, Douwe J. J.; Lodolo, Emanuele

    2015-12-01

    The southernmost segment of the Andean Cordillera underwent a complex deformation history characterized by alternation of contractional, extensional, and strike-slip tectonics. Key elements of southern Andean deformation that remain poorly constrained, include the origin of the orogenic bend known as the Patagonian Orocline (here renamed as Patagonian Arc), and the exhumation mechanism of an upper amphibolite facies metamorphic complex currently exposed in Cordillera Darwin. Here, we present results of anisotropy of magnetic susceptibility (AMS) from 22 sites in Upper Cretaceous to upper Eocene sedimentary rocks within the internal structural domain of the Magallanes fold-and-thrust belt in Tierra del Fuego (Argentina). AMS parameters from most sites reveal a weak tectonic overprint of the original magnetic fabric, which was likely acquired upon layer-parallel shortening soon after sedimentation. Magnetic lineation from 17 sites is interpreted to have formed during compressive tectonic phases associated to a continuous N-S contraction. Our data, combined with the existing AMS database from adjacent areas, show that the Early Cretaceous-late Oligocene tectonic phases in the Southern Andes yielded continuous contraction, variable from E-W in the Patagonian Andes to N-S in the Fuegian Andes, which defined a radial strain field. A direct implication is that the exhumation of the Cordillera Darwin metamorphic complex occurred under compressive, rather than extensional or strike-slip tectonics, as alternatively proposed. If we agree with recent works considering the curved Magallanes fold-and-thrust belt as a primary arc (i.e., no relative vertical-axis rotation of the limbs occurs during its formation), then other mechanisms different from oroclinal bending should be invoked to explain the documented radial strain field. We tentatively propose a kinematic model in which reactivation of variably oriented Jurassic faults at the South American continental margin controlled

  11. Motion robust magnetic susceptibility and field inhomogeneity estimation using regularized image restoration techniques for fMRI.

    PubMed

    Yeo, Desmond Teck Beng; Fessler, Jeffrey A; Kim, Boklye

    2008-01-01

    In functional MRI, head motion may cause dynamic nonlinear field-inhomogeneity changes, especially with large out-of-plane rotations. This may lead to dynamic geometric distortion or blurring in the time series, which may reduce activation detection accuracy. The use of image registration to estimate dynamic field inhomogeneity maps from a static field map is not sufficient in the presence of such rotations. This paper introduces a retrospective approach to estimate magnetic susceptibility induced field maps of an object in motion, given a static susceptibility induced field map and the associated object motion parameters. It estimates a susceptibility map from a static field map using regularized image restoration techniques, and applies rigid body motion to the former. The dynamic field map is then computed using susceptibility voxel convolution. The method addresses field map changes due to out-of-plane rotations during time series acquisition and does not involve real time field map acquisitions.

  12. 1D magnetic interactions in Cu(II) oxovanadium phosphates (VPO), magnetic susceptibility, DFT, and single-crystal EPR.

    PubMed

    Venegas-Yazigi, Diego; Spodine, Evgenia; Saldias, Marianela; Vega, Andrés; Paredes-García, Verónica; Calvo, Rafael; de Santana, Ricardo Costa

    2015-04-20

    We report the crystal face indexing and molecular spatial orientation, magnetic properties, electron paramagnetic resonance (EPR) spectra, and density functional theory (DFT) calculations of two previously reported oxovanadium phosphates functionalized with Cu(II) complexes, namely, [Cu(bipy)(VO2)(PO4)]n (1) and [{Cu(phen)}2(VO2(H2O)2)(H2PO4)2 (PO4)]n (2), where bipy = 2,2'-bipyridine and phen = 1,10-phenanthroline, obtained by a new synthetic route allowing the growth of single crystals appropriate for the EPR measurements. Compounds 1 and 2 crystallize in the triclinic group P1̅ and in the orthorhombic Pccn group, respectively, containing dinuclear copper units connected by two -O-P-O- bridges in 1 and by a single -O-P-O- bridge in 2, further connected through -O-P-O-V-O- bridges. We emphasize in our work the structural aspects related to the chemical paths that determine the magnetic properties. Magnetic susceptibility data indicate bulk antiferromagnetism for both compounds, allowing to calculate J = -43.0 cm(-1) (dCu-Cu = 5.07 Å; J defined as Hex(i,j) = -J Si·Sj), considering dinuclear units for 1, and J = -1.44 cm(-1) (dCu-Cu = 3.47 Å) using the molecular field approximation for 2. The single-crystal EPR study allows evaluation of the g matrices, which provide a better understanding of the electronic structure. The absence of structure of the EPR spectra arising from the dinuclear character of the compounds allows estimation of weak additional exchange couplings |J'| > 0.3 cm(-1) for 1 (dCu-Cu = 5.54 Å) and a smaller value of |J'| ≥ 0.15 cm(-1) for 2 (dCu-Cu = 6.59 Å). DFT calculations allow evaluating two different exchange couplings for each compound, specifically, J = -36.60 cm(-1) (dCu-Cu = 5.07 Å) and J' = 0.20 cm(-1) (dCu-Cu =5.54 Å) for 1 and J = -1.10 cm(-1) (dCu-Cu =3.47 Å) and J' = 0.01 cm(-1) (dCu-Cu = 6.59 Å) for 2, this last value being in the range of the uncertainties of the calculations. Thus, these values are in good agreement

  13. The generalised Sylvester matrix equations over the generalised bisymmetric and skew-symmetric matrices

    NASA Astrophysics Data System (ADS)

    Dehghan, Mehdi; Hajarian, Masoud

    2012-08-01

    A matrix P is called a symmetric orthogonal if P = P T = P -1. A matrix X is said to be a generalised bisymmetric with respect to P if X = X T = PXP. It is obvious that any symmetric matrix is also a generalised bisymmetric matrix with respect to I (identity matrix). By extending the idea of the Jacobi and the Gauss-Seidel iterations, this article proposes two new iterative methods, respectively, for computing the generalised bisymmetric (containing symmetric solution as a special case) and skew-symmetric solutions of the generalised Sylvester matrix equation ? (including Sylvester and Lyapunov matrix equations as special cases) which is encountered in many systems and control applications. When the generalised Sylvester matrix equation has a unique generalised bisymmetric (skew-symmetric) solution, the first (second) iterative method converges to the generalised bisymmetric (skew-symmetric) solution of this matrix equation for any initial generalised bisymmetric (skew-symmetric) matrix. Finally, some numerical results are given to illustrate the effect of the theoretical results.

  14. Measuring the magnetic-field-dependent chemical potential of a low-density three-dimensional electron gas in n -GaAs and extracting its magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Roy Choudhury, Aditya N.; Venkataraman, V.

    2016-01-01

    We report the magnetic-field-dependent shift of the electron chemical potential in bulk, n -type GaAs at room temperature. A transient voltage of ˜100 μ V was measured across a Au-Al2O3 -GaAs metal-oxide-semiconductor capacitor in a pulsed magnetic field of ˜6 T . Several spurious voltages larger than the signal that had plagued earlier researchers performing similar experiments were carefully eliminated. The itinerant magnetic susceptibility of GaAs is extracted from the experimentally measured data for four different doping densities, including one as low as 5 ×1015cm-3 . Though the susceptibility in GaAs is dominated by Landau-Peierls diamagnetism, the experimental technique demonstrated can be a powerful tool for extracting the total free carrier magnetization of any electron system. The method is also virtually independent of the carrier concentration and is expected to work better in the nondegenerate limit. Such experiments had been successfully performed in two-dimensional electron gases at cryogenic temperatures. However, an unambiguous report on having observed this effect in any three-dimensional electron gas has been lacking. We highlight the 50 year old literature of various trials and discuss the key details of our experiment that were essential for its success. The technique can be used to unambiguously yield only the itinerant part of the magnetic susceptibility of complex materials such as magnetic semiconductors and hexaborides, and thus shed light on the origin of ferromagnetism in such systems.

  15. Mössbauer spectroscopy, magnetization, magnetic susceptibility, and low temperature heat capacity of α-Na2NpO4

    NASA Astrophysics Data System (ADS)

    Smith, Anna L.; Hen, Amir; Magnani, Nicola; Sanchez, Jean-Pierre; Colineau, Eric; Griveau, Jean-Christophe; Raison, Philippe E.; Caciuffo, Roberto; Konings, Rudy J. M.; Cheetham, Anthony K.

    2016-03-01

    The physical and chemical properties at low temperatures of hexavalent disodium neptunate α-Na2NpO4 are investigated for the first time in this work using Mössbauer spectroscopy, magnetization, magnetic susceptibility, and heat capacity measurements. The Np(VI) valence state is confirmed by the isomer shift value of the Mössbauer spectra, and the local structural environment around the neptunium cation is related to the fitted quadrupole coupling constant and asymmetry parameters. Moreover, magnetic hyperfine splitting is reported below 12.5 K, which could indicate magnetic ordering at this temperature. This interpretation is further substantiated by the existence of a λ-peak at 12.5 K in the heat capacity curve, which is shifted to lower temperatures with the application of a magnetic field, suggesting antiferromagnetic ordering. However, the absence of any anomaly in the magnetization and magnetic susceptibility data shows that the observed transition is more intricate. In addition, the heat capacity measurements suggest the existence of a Schottky-type anomaly above 15 K associated with a low-lying electronic doublet found about 60 cm-1 above the ground state doublet. The possibility of a quadrupolar transition associated with a ground state pseudoquartet is thereafter discussed. The present results finally bring new insights into the complex magnetic and electronic peculiarities of α-Na2NpO4.

  16. Magnetic susceptibility of Dirac fermions, Bi-Sb alloys, interacting Bloch fermions, dilute nonmagnetic alloys, and Kondo alloys

    NASA Astrophysics Data System (ADS)

    Buot, Felix A.; Otadoy, Roland E. S.; Rivero, Karla B.

    2017-03-01

    Wide ranging interest in Dirac Hamiltonian is due to the emergence of novel materials, namely, graphene, topological insulators and superconductors, the newly-discovered Weyl semimetals, and still actively-sought after Majorana fermions in real materials. We give a brief review of the relativistic Dirac quantum mechanics and its impact in the developments of modern physics. The quantum band dynamics of Dirac Hamiltonian is crucial in resolving the giant diamagnetism of bismuth and Bi-Sb alloys. Quantitative agreement of the theory with the experiments on Bi-Sb alloys has been achieved, and physically meaningful contributions to the diamagnetism has been identified. We also treat relativistic Dirac fermion as an interband dynamics in uniform magnetic fields. For the interacting Bloch electrons, the role of translation symmetry for calculating the magnetic susceptibility avoids any approximation to second order in the field. The expressions for magnetic susceptibility of dilute nonmagnetic alloys give a firm theoretical foundation of the empirical formulas used in fitting experimental results. The unified treatment of all the above calculations is based on the lattice Weyl-Wigner formulation of discrete phase-space quantum mechanics. For completeness, the magnetic susceptibility of Kondo alloys is also given since Dirac fermions in conduction band and magnetic impurities exhibit Kondo effect.

  17. Magnetic susceptibility of the South African Agouron scientific drillcores quantifies iron and sulfur alteration relevant to geochemical oxygenation proxies

    NASA Astrophysics Data System (ADS)

    Raub, T. D.; Nayak, P. M.; Tikoo, S. M.; Johnson, J. E.; Peek, S.; Fischer, W. W.; Kirschvink, J. L.

    2010-12-01

    Various geochemical characteristics of sedimentary iron- and sulfur-bearing minerals motivate early- to late-oxygenation hypotheses from South African and Australian scientific drillcores. Most intervals of these drillcores appear to be remagnetized (in some cases multiple times); and ~2.0 Ga magnetic sulfide crystallization is particularly pervasive in carbonaceous siltstones of the ca. 2.7-2.2 Ga Griqualand margin of Kaapvaal craton. Robust interpretation of trace element abundances suggesting “whiffs” to “pervasive” levels of late Archean oxygen depends upon systematics of presumed depositional iron speciation; so multiple iron- and sulfur-mineral-altering events affecting existing drillcore records call straightforward interpretations into question. We report ca. 10,000 magnetic susceptibility measurements and associated detailed rock-magnetic results from all lithologies of Archean basinal and slope facies in drillcores GKP and GKF and relatively younger and shallower facies in Paleoproterozoic drillcores GEC and GTF. Specific carbonaceous siltstone and carbonate intervals are less-altered as revealed by coherent and relatively low magnetic susceptibilities: geochemical and biomarker interpretations based upon data from these intervals should be preferred to those from others. Magnetic susceptibility tracks subtle facies variation in drillcore GTF diamictite and suggests highly-structured Paleoproterozoic glacioeustatic sequence architecture consistent with assignment of Makganyene glaciation and its associated geochemical signature to a ca. 2.2 Ga “Snowball Earth” ice age.

  18. A method for the integration of satellite vegetation activities observations and magnetic susceptibility measurements for monitoring heavy metals in soil.

    PubMed

    D'Emilio, Mariagrazia; Macchiato, Maria; Ragosta, Maria; Simoniello, Tiziana

    2012-11-30

    We present a procedure for monitoring heavy metals in soil based on the integration of satellite and ground-based techniques, tested in an area affected by high anthropogenic pressure. High resolution multispectral satellite data were elaborated to obtain information on vegetation status. Magnetic susceptibility measurements of soils were collected as proxy variable for monitoring heavy metal presence. Chemical analyses of heavy metals were used for supporting and validating the integrated monitoring procedure. Magnetic and chemical measurements were organized in a GIS environment to be overlapped to satellite-based elaborations and to analyze the pattern distribution. Results show the presence of correlation between anomalies in vegetation activity and soil characteristics. The relationship between the distribution of normalized difference vegetation index anomalies and magnetic susceptibility values provides hints for adopting the integrated procedure as preliminary screening to minimize monitoring efforts and costs by supporting the planning activities of field campaigns.

  19. Anisotropy of out-of-phase magnetic susceptibility of rocks as a tool for direct determination of magnetic sub-fabrics of some minerals: An introductory study

    NASA Astrophysics Data System (ADS)

    Hrouda, František; Chadima, Martin; Ježek, Josef; Pokorný, Jiří

    2016-10-01

    The magnetic susceptibility measured in alternating field can in general be resolved into a component that is in-phase with the applied field and a component that is out-of-phase. While in non-conductive diamagnetic, paramagnetic and many ferromagnetic materials the phase is effectively zero, in some ferromagnetic minerals, such as pyrrhotite, hematite, titanomagnetite or small magnetically viscous grains of magnetite, it is clearly non-zero. The anisotropy of out-of-phase susceptibility (opAMS) can then be used as a tool for the direct determination of the magnetic sub-fabrics of the minerals with non-zero phase. The error in determination of out-of-phase susceptibility non-linearly increases with decreasing phase angle. This may result in imprecise determination of the opAMS in specimens with very low phase angle. The degree of opAMS is higher than that of ipAMS, which may in contrast result in slightly increasing precision n the opAMS determination. It is highly recommended to inspect the results of the statistical tests of each specimen and to exclude the specimens whose opAMS is determined with insufficient precision from further processing. In rocks, whose magnetism is dominated by the mineral with non-zero out-of-phase susceptibility, the principal directions of the opAMS and ipAMS are virtually coaxial, while the degree of opAMS is higher than that of ipAMS. In some specific cases, the opAMS provides us with similar data to those provided by anisotropies of low-field dependent susceptibility and frequency-dependent susceptibility. The advantage of the opAMS compared to the other two anisotropies is its simultaneous measurement with the ipAMS during one measuring process, while the other two anisotropies require the AMS measurements in several fields or at least at two operating frequencies.

  20. Anisotropy of out-of-phase magnetic susceptibility of rocks as a tool for direct determination of magnetic subfabrics of some minerals: an introductory study

    NASA Astrophysics Data System (ADS)

    Hrouda, František; Chadima, Martin; Ježek, Josef; Pokorný, Jiří

    2017-01-01

    The magnetic susceptibility measured in alternating field can in general be resolved into a component that is in-phase with the applied field and a component that is out-of-phase. While in non-conductive diamagnetic, paramagnetic and many ferromagnetic materials the phase is effectively zero, in some ferromagnetic minerals, such as pyrrhotite, hematite, titanomagnetite or small magnetically viscous grains of magnetite, it is clearly non-zero. The anisotropy of out-of-phase susceptibility (opAMS) can then be used as a tool for the direct determination of the magnetic subfabrics of the minerals with non-zero phase. The error in determination of out-of-phase susceptibility non-linearly increases with decreasing phase angle. This may result in imprecise determination of the opAMS in specimens with very low phase angle. The degree of opAMS is higher than that of ipAMS, which may in contrast result in slightly increasing precision n the opAMS determination. It is highly recommended to inspect the results of the statistical tests of each specimen and to exclude the specimens whose opAMS is determined with insufficient precision from further processing. In rocks, whose magnetism is dominated by the mineral with non-zero out-of-phase susceptibility, the principal directions of the opAMS and ipAMS are virtually coaxial, while the degree of opAMS is higher than that of ipAMS. In some specific cases, the opAMS provides us with similar data to those provided by anisotropies of low-field dependent susceptibility and frequency-dependent susceptibility. The advantage of the opAMS compared to the other two anisotropies is its simultaneous measurement with the ipAMS during one measuring process, while the other two anisotropies require the AMS measurements in several fields or at least at two operating frequencies.

  1. Comparison of optomagnetic and AC susceptibility readouts in a magnetic nanoparticle agglutination assay for detection of C-reactive protein.

    PubMed

    Fock, Jeppe; Parmvi, Mattias; Strömberg, Mattias; Svedlindh, Peter; Donolato, Marco; Hansen, Mikkel Fougt

    2017-02-15

    There is an increasing need to develop biosensor methods that are highly sensitive and that can be combined with low-cost consumables. The use of magnetic nanoparticles (MNPs) is attractive because their detection is compatible with low-cost disposables and because application of a magnetic field can be used to accelerate assay kinetics. We present the first study and comparison of the performance of magnetic susceptibility measurements and a newly proposed optomagnetic method. For the comparison we use the C-reactive protein (CRP) induced agglutination of identical samples of 100nm MNPs conjugated with CRP antibodies. Both methods detect agglutination as a shift to lower frequencies in measurements of the dynamics in response to an applied oscillating magnetic field. The magnetic susceptibility method probes the magnetic response whereas the optomagnetic technique probes the modulation of laser light transmitted through the sample. The two techniques provided highly correlated results upon agglutination when they measure the decrease of the signal from the individual MNPs (turn-off detection strategy), whereas the techniques provided different results, strongly depending on the read-out frequency, when detecting the signal due to MNP agglomerates (turn-on detection strategy). These observations are considered to be caused by differences in the volume-dependence of the magnetic and optical signals from agglomerates. The highest signal from agglomerates was found in the optomagnetic signal at low frequencies.

  2. Spatial variability of soil magnetic susceptibility in an agricultural field located in Eastern Ukraine

    NASA Astrophysics Data System (ADS)

    Menshov, Oleksandr; Pereira, Paulo; Kruglov, Oleksandr

    2015-04-01

    Magnetic susceptibility (MS) have been used to characterize soil properties. It gives an indirect information about heavy metals content and degree of human impacts on soil contamination derived from atmospheric pollution (Girault et al., 2011). This method is inexpensive in relation to chemical analysis and very useful to track soil pollution, since several toxic components deposited on soil surface are rich in particulates produced by oxidation processes (Boyko et al., 2004; Morton-Bernea et al., 2009). Thus, identify the spatial distribution of MS is of major importance, since can give an indirect information of high metals content (Dankoub et al., 2012). This allows also to distinguish the pedogenic and technogenic origin magnetic signal. For example Ukraine chernozems contain fine-grained oxidized magnetite and maghemite of pedogenic origin formed by weathering of the parent material (Jeleńska et al., 2004). However, to a correct understanding of variables distribution, the identification of the most accurate interpolation method is fundamental for a better interpretation of map information (Pereira et al., 2013). The objective of this work is to study the spatial variability of soil MS in an agricultural fields located in the Tcherkascy Tishki area (50.11°N, 36.43 °E, 162 m a.s.l), Ukraine. Soil MS was measured in 77 sampling points in a north facing slope. To estimate the best interpolation method, several interpolation methods were tested, as inverse distance to a weight (IDW) with the power of 1,2,3,4 and 5, Local Polynomial (LP) with the power of 1 and 2, Global Polynomial (GP), radial basis functions - spline with tension (SPT), completely regularized spline (CRS), multiquatratic (MTQ), inverse multiquatratic (IMTQ), and thin plate spline (TPS) - and some geostatistical methods as, ordinary kriging (OK), Simple Kriging (SK) and Universal Kriging (UK), used in previous works (Pereira et al., 2014). On average, the soil MS of the studied plot had 686

  3. Diagenetic Control Of The Magnetic Susceptibility Variations In Core MD98-2172 In The Eastern Timor Sea

    NASA Astrophysics Data System (ADS)

    Li, H.; Zhang, S.; Bai, L.; Fang, N.

    2008-12-01

    Detailed mineral magnetic measurements, integrated with grain-size distribution and X-ray diffraction (XRD) analyses, were made on the marine sediments of Core MD98-2172, retrieved from the Eastern Timor Sea. Values of magnetic susceptibility of this core drop sharply down-core since the depth of ~3.85 m and get to very low at ~5.35 m. But both results of XRD and grain-size distribution show no sudden change of the terrigenous input through the whole core. Mineral magnetic results indicate that the depth of ~3.85 m below the sediment/water interface may be an oxic/anoxic boundary and the sediments below ~3.85 m have been greatly subjected to the reductive diagenesis, while the sediments of the top ~3.85 m are seldom affected. The magnetic properties of the top 3.85-m sediments are dominated by pseudo-single domain (PSD) magnetite, and its content and grain size show little down-core variations. While the magnetic mineral assemblages that have survived in the sediments below ~3.85 m may record different stages of the reductive diagenesis: (1) the sediments from the 3.85-5.35 m interval are at the stage of iron oxide reduction; PSD magnetite is the major magnetic contributor, but it becomes less abundant and coarser down-core; (2) the sediments below ~5.35 m are at the stage of sulphate reduction; ferrimagnetic minerals almost vanish and paramagnetic minerals contribute to the susceptibility down-core variations, including pyrite as evidenced by high-temperature magnetic susceptibility measurements. However, the susceptibility variations below ~5.35 m of Core MD98-2172 show obvious periodicity, despite the intense effect of reductive diagenesis. Furthermore, the susceptibility down-core variations are coincident with the fluctuations of the amounts of fine detrital particles (<8 μm), which may mainly come from the advection of the Indonesia Throughflow and/or the river input from the Timor Island. Therefore, for Core MD98-2172, the susceptibility variations below ~5

  4. Diagenetic control of magnetic susceptibility variation in Core MD98-2172 from the Eastern Timor Sea

    NASA Astrophysics Data System (ADS)

    Li, Haiyan; Zhang, Shihong; Bai, Lingyan; Fang, Nianqiao

    2010-11-01

    Detailed mineral magnetic measurements, integrated with grain-size distribution and X-ray diffraction (XRD) analyses, were made on the marine sediments of Core MD98-2172, retrieved from the Eastern Timor Sea. Values of magnetic susceptibility in this core drop sharply down-core from ˜3.85 m deep below sediment/water interface and are very low at ˜5.35 m. However, both XRD and grain-size distribution results show no sudden change in terrigenous input during sedimentation. Mineral magnetic results indicate that the depth of ˜3.85 m may be an oxic/anoxic boundary. Therefore, the sediments below ˜3.85 m have been subjected to intense reductive diagenesis, whereas the sediments above ˜3.85 m are seldom affected. The magnetic properties of the sediments shallower than 3.85 m are dominated by pseudo-single domain (PSD) magnetite, with little down-core variation in its content and grain size. Below ˜3.85 m, the magnetic mineral assemblages that have survived in the sediments may record different stages of the reductive diagenesis: (1) the sediments from the 3.85-5.35 m interval are at the stage of iron oxide reduction; PSD magnetite is the major magnetic contributor, but it becomes less abundant and coarser down-core; (2) the sediments below ˜5.35 m are at the stage of sulphate reduction; ferrimagnetic minerals almost vanish and paramagnetic minerals contribute to down-core susceptibility variations, including pyrite as evidenced by high-temperature magnetic susceptibility measurements. However, the susceptibility variations below ˜5.35 m of Core MD98-2172 show obvious periodicity, despite the intense effect of reductive diagenesis. Furthermore, the down-core susceptibility variations are coincident with fluctuations in the quantity of fine detrital particles (<8 μm), which may come mainly from the advection of the Indonesia Throughflow (ITF) and/or river input from Timor. Therefore, for Core MD98-2172, susceptibility variation below ˜5.35 m, which potentially

  5. The anisotropy of magnetic susceptibility of uniaxial superparamagnetic particles: Consequences for its interpretation in magnetite and maghemite bearing rocks

    NASA Astrophysics Data System (ADS)

    Lanci, Luca; Zanella, Elena

    2016-01-01

    A simple model that provides a quantitative description of the magnetic susceptibility of superparamagnetic to stable single-domain uniaxial magnetic particles can be built in the framework of the theory of stochastic resonance. This model expands that of Mullins and Tile (1973) for superparamagnetic grains by considering the dependence of superparamagnetic susceptibility on the particle orientation and thus describes the anisotropy of magnetic susceptibility (AMS) of ensembles of superparamagnetic as well as single-domain particles. The theory predicts that on the contrary of stable single domain, the maximum anisotropy of superparamagnetic particles is parallel to their easy axis and shows that the AMS of ensembles of uniaxial particle is strongly dependent on the distribution of particle grain size, coercivity, measurement temperature, and frequency. It also explains why the inverse AMS pattern expected for stable single-domain particles is rarely observed in natural samples. We use examples of well-characterized obsidian specimens to show that, as predicted by the theory, in the presence of significant superparamagnetic contributions, the maximum susceptibility axis of AMS is directed along the preferential direction of particles easy axis.

  6. Diagnostic accuracy of susceptibility-weighted magnetic resonance imaging for the evaluation of pineal gland calcification

    PubMed Central

    Böker, Sarah M.; Bender, Yvonne Y.; Diederichs, Gerd; Fallenberg, Eva M.; Wagner, Moritz; Hamm, Bernd; Makowski, Marcus R.

    2017-01-01

    Objectives To determine the diagnostic performance of susceptibility-weighted magnetic resonance imaging (SWMR) for the detection of pineal gland calcifications (PGC) compared to conventional magnetic resonance imaging (MRI) sequences, using computed tomography (CT) as a reference standard. Methods 384 patients who received a 1.5 Tesla MRI scan including SWMR sequences and a CT scan of the brain between January 2014 and October 2016 were retrospectively evaluated. 346 patients were included in the analysis, of which 214 showed PGC on CT scans. To assess correlation between imaging modalities, the maximum calcification diameter was used. Sensitivity and specificity and intra- and interobserver reliability were calculated for SWMR and conventional MRI sequences. Results SWMR reached a sensitivity of 95% (95% CI: 91%-97%) and a specificity of 96% (95% CI: 91%-99%) for the detection of PGC, whereas conventional MRI achieved a sensitivity of 43% (95% CI: 36%-50%) and a specificity of 96% (95% CI: 91%-99%). Detection rates for calcifications in SWMR and conventional MRI differed significantly (95% versus 43%, p<0.001). Diameter measurements between SWMR and CT showed a close correlation (R2 = 0.85, p<0.001) with a slight but not significant overestimation of size (SWMR: 6.5 mm ± 2.5; CT: 5.9 mm ± 2.4, p = 0.02). Interobserver-agreement for diameter measurements was excellent on SWMR (ICC = 0.984, p < 0.0001). Conclusions Combining SWMR magnitude and phase information enables the accurate detection of PGC and offers a better diagnostic performance than conventional MRI with CT as a reference standard. PMID:28278291

  7. Impacts of geology and land use on magnetic susceptibility and selected heavy metals in surface soils of Mashhad plain, northeastern Iran

    NASA Astrophysics Data System (ADS)

    Karimi, Alireza; Haghnia, Gholam Hosain; Ayoubi, Shamsollah; Safari, Tayebeh

    2017-03-01

    Magnetic susceptibility is a fast, inexpensive and reliable technique for estimating and monitoring the anthropogenic contamination of soil with heavy metals. However, it is essential to determine the factors affecting magnetic susceptibility before applying this technique to environmental studies. The objectives of this study were to investigate i) the effect of parent materials and land use on the magnetic susceptibility and concentrations of Fe, Ni, Pb and Zn, and ii) capability of magnetic susceptibility as an indicator of anthropogenic heavy metals contamination of soil in Mashhad plain, northeastern Iran. One hundred seventy-eight composite surface soil samples (0-10 cm) were taken. The aqua-regia extractable concentrations of Fe, Ni, Zn and Pb were determined by atomic absorption spectroscopy. Magnetic susceptibility at low and high frequency (χlf and χhf) were measured and frequency dependent susceptibility (χfd) was calculated. The average concentrations of Fe, Ni, Pb and Zn were 22,812, 61.4, 74.1 and 31.6 mg kg- 1, respectively. The highest contents of Pb (69.1 mg kg- 1) and Zn (149 mg kg- 1) were observed in urban area. The highest concentration of Ni was 41,538 mg kg- 1 observed in the soils developed from ultramafic rocks. Magnetic susceptibility varied from 20.3 on marly sediments to 311.8 × 10- 8 m3 kg- 1 on ultramafic rocks. A positive strong correlation (Pvalue < 0.01, r = 0.88) was obtained between Ni and χlf. There were no significant relationships between Zn and Pb with χlf, therefore it seems that magnetic susceptibility has not been affected significantly by anthropogenic activities which enhanced Pb and Zn concentrations in urban soils. The results indicated that magnetic susceptibility was mainly controlled by Ni containing minerals with lithogenic origin. Therefore, in the soils studied, magnetic susceptibility could not be employed as indicator of anthropogenic contamination of soil with heavy metals.

  8. Susceptibility investigation of the nanoparticle coating-layer effect on the particle interaction in biocompatible magnetic fluids

    NASA Astrophysics Data System (ADS)

    Morais, P. C.; Santos, J. G.; Silveira, L. B.; Gansau, C.; Buske, N.; Nunes, W. C.; Sinnecker, J. P.

    2004-05-01

    AC susceptibility was used to investigate the effect of the surface-coating layer in two biocompatible, magnetite-based, magnetic fluid samples. Dextran and dimercaptosuccinic acid (DMSA) were the surface coating species. The temperature and frequency dependence of the peak susceptibility was discussed using the Vogel-Fulcher relation, from which the typical energy barrier (temperature correction) values of 1340±20 K (70±3 K) and 1230±30 K (86±5 K) were obtained for the dextran- and DMSA-coated nanoparticles, respectively.

  9. Magnetic susceptibility as an indicator to paleo-environmental pollution in an urban lagoon near Istanbul city

    NASA Astrophysics Data System (ADS)

    Alpar, Bedri; Unlu, Selma; Altinok, Yildiz; Ongen, Sinan

    2014-05-01

    For assessing anthropogenic pollution, magnetic susceptibility profiles and accompanying data were measured along three short cores recovered at the southern part of an urban lagoon; Kucukcekmece, Istanbul, Turkey. This marine inlet, connected to the Sea of Marmara by a very narrow channel, was used as a drinking water reservoir 40-50 years ago before it was contaminated by municipal, agricultural and industrial activities, mainly carried by three streams feeding the lagoon. The magnetic signals decrease gradually from the lake bottom towards the core base showing some characteristic anomalies. These signatures were tested as an environmental magnetic parameter against the lithological diversity (silici-clastic, total organic matter and carbonate), metal enrichments with larger variations (Pb, Mn, Zn, Ni, Co, Cr, U and Al) and probable hydrocarbon contamination. Mineral assemblage was determined by a computer driven X-ray diffractometer. The heavy metal concentrations and total petroleum hydrocarbons (TPH) were measured by ICP-MS and UVF spectrometry, respectively. Magnetic susceptibility shows slightly higher values in interlayers containing higher silici-clastic material and organic content which may suggest first-order changes in the relative supplies of terrigenous and biogenic materials. On the basis of cluster analyses, enhanced magnetic signals could be correlated with the elevated concentrations of Co, Zn, U, Pb and TPH along the cores. The Pb concentrations at the upper parts of the cores were higher than the "Severe Effect Level" and could pose a potential risk for living organisms. Greater amounts of organic carbon tend to accumulate in muddy sediments. In fact, there are a few studies reporting some relationship between enhanced magnetic signals and organic contamination mainly due to petroleum aromatic hydrocarbons. In conclusion, the magnetic susceptibility changes in sedimentary depositional environments could be used as a rapid and cost

  10. Pauli magnetic susceptibility of bilayer graphene and hexagonal boron-nitride

    NASA Astrophysics Data System (ADS)

    Mousavi, Hamze; Jalilvand, Samira; Kurdestany, Jamshid Moradi

    2016-12-01

    We study the contribution of s and p orbitals on the Pauli magnetic susceptibility (PMS) and density of state (DOS) of the following three structures (1) bilayer graphene (2) bilayer boron-nitride (BN) and (3) bilayer graphene-BN within a two-band tight-binding Harrison Hamiltonian and the Green's function technique. It is shown that in all three cases, the contribution of s and px or py orbitals have no states around the Fermi level, while for bilayer graphene and graphene-BN the total DOS and DOS of pz orbital appear to be a linear function around this level. We show explicitly that for bilayer BN the contribution of pz orbital does not have states around the Fermi level, because of ionization energy difference between the boron (B) and nitrogen (N) atoms. We find that the bandwidth of s, px or py is more extension than case of pz orbital as a result of the Van-Hove singularities in the DOS. This leads to consideration of the PMS in two, low and high temperature, regions.

  11. Anisotropic Change in the Magnetic Susceptibility of a Dynamic Single Crystal of a Cobalt(II) Complex.

    PubMed

    Yao, Zi-Shuo; Wu, Shu-Qi; Kitagawa, Yasutaka; Su, Sheng-Qun; Huang, You-Gui; Li, Guo-Ling; Ni, Zhong-Hai; Nojiri, Hiroyuki; Shiota, Yoshihito; Yoshizawa, Kazunari; Kang, Soonchul; Kanegawa, Shinji; Sato, Osamu

    2017-01-16

    Atypically anisotropic and large changes in magnetic susceptibility, along with a change in crystalline shape, were observed in a Co(II) complex at near room temperature. This was achieved by combining oxalate molecules, acting as rotor, and a Co(II) ion with unquenched orbital angular momentum. A thermally controlled 90° rotation of the oxalate counter anion triggered a symmetry-breaking ferroelastic phase transition, accompanied by contraction-expansion behavior (ca. 4.5 %) along the long axis of a rod-like single crystal. The molecular rotation induced a minute variation in the coordination geometry around the Co(II) ion, resulting in an abrupt decrease and a remarkable increase in magnetic susceptibility along the direction perpendicular and parallel to the long axis of the crystal, respectively. Theoretical calculations suggested that such an unusual anisotropic change in magnetic susceptibility was due to a substantial reorientation of magnetic anisotropy induced by slight disruption in the ideal D3 coordination environment of the complex cation.

  12. Magnetic susceptibility measurements as proxy method to monitor soil pollution: the case study of S. Nicola di Melfi.

    PubMed

    D'Emilio, Mariagrazia; Caggiano, Rosa; Coppola, Rosa; Macchiato, Maria; Ragosta, Maria

    2010-10-01

    The development of in situ, cheep, noninvasive, and fast strategies for soil monitoring is a crucial task for environmental research. In this paper, we present the results of three field surveys carried out in an industrial area of Southern Italy: S. Nicola di Melfi. The monitoring procedure is based on soil magnetic susceptibility measurements carried out by means of experimental protocols that our research group developed during the last years. This field surveys is supported by both geological characterization of the area and analytical determinations of metal concentrations in soils. Magnetic studies were carried out not only in situ but also in laboratory. Results show that, taking into account the influence due to the geomorphologic difference, soil magnetic susceptibility is an optimal indicator of the anthropogenic impact. So, our monitoring strategy discloses that the combined use of magnetic susceptibility measurements and soil geomorphology information may be used as a useful tool for the temporal monitoring of pollution evolution and for a fast screening of polluted zones.

  13. Magnetothermal Convection of Water with the Presence or Absence of a Magnetic Force Acting on the Susceptibility Gradient

    PubMed Central

    Maki, Syou

    2016-01-01

    Heat transfer of magnetothermal convection with the presence or absence of the magnetic force acting on the susceptibility gradient (fsc) was examined by three-dimensional numerical computations. Thermal convection of water enclosed in a shallow cylindrical vessel (diameter over vessel height = 6.0) with the Rayleigh-Benard model was adopted as the model, under the conditions of Prandtl number 6.0 and Ra number 7000, respectively. The momentum equations of convection were nondimensionalized, which involved the term of fsc and the term of magnetic force acting on the magnetic field gradient (fb). All the computations resulted in axisymmetric steady rolls. The values of the averaged Nu, the averaged velocity components U, V, and W, and the isothermal distributions and flow patterns were almost completely the same, regardless of the presence or absence of the term of fsc. As a result, we found that the effect of fsc was extremely small, although much previous research emphasized the effect with paramagnetic solutions under an unsteady state. The magnitude of fsc depends not only on magnetic conditions (magnitudes of magnetic susceptibility and magnetic flux density), but also on the thermal properties of the solution (thermal conductivity, thermal diffusivity, and viscosity). Therefore the effect of fb becomes dominant on the magnetothermal convection. Active control over the density gradient with temperature will be required to advance heat transfer with the effect of fsc. PMID:27606823

  14. Susceptibility of CoFeB/AlOx/Co Magnetic Tunnel Junctions to Low-Frequency Alternating Current

    PubMed Central

    Chen, Yuan-Tsung; Chang, Zu-Gao

    2013-01-01

    This investigation studies CoFeB/AlOx/Co magnetic tunneling junction (MTJ) in the magnetic field of a low-frequency alternating current, for various thicknesses of the barrier layer AlOx. The low-frequency alternate-current magnetic susceptibility (χac) and phase angle (θ) of the CoFeB/AlOx/Co MTJ are determined using an χac analyzer. The driving frequency ranges from 10 to 25,000 Hz. These multilayered MTJs are deposited on a silicon substrate using a DC and RF magnetron sputtering system. Barrier layer thicknesses are 22, 26, and 30 Å. The X-ray diffraction patterns (XRD) include a main peak at 2θ = 44.7° from hexagonal close-packed (HCP) Co with a highly (0002) textured structure, with AlOx and CoFeB as amorphous phases. The full width at half maximum (FWHM) of the Co(0002) peak, decreases as the AlOx thickness increases; revealing that the Co layer becomes more crystalline with increasing thickness. χac result demonstrates that the optimal resonance frequency (fres) that maximizes the χac value is 500 Hz. As the frequency increases to 1000 Hz, the susceptibility decreases rapidly. However, when the frequency increases over 1000 Hz, the susceptibility sharply declines, and almost closes to zero. The experimental results reveal that the mean optimal susceptibility is 1.87 at an AlOx barrier layer thickness of 30 Å because the Co(0002) texture induces magneto-anisotropy, which improves the indirect CoFeB and Co spin exchange-coupling strength and the χac value. The results concerning magnetism indicate that the magnetic characteristics are related to the crystallinity of Co.

  15. Model calculation of the static magnetic susceptibility in light rare earth metallic systems

    NASA Astrophysics Data System (ADS)

    Hammoud, Y.; Parlebas, J. C.

    1991-05-01

    Using the impurity Anderson model in the large N_f approximation, where N_f is the orbital and spin degeneracy of the f level, we calculate the zero temperature static paramagnetic susceptibility of light rare earth metallic systems. The calculation is performed for large values of the Coulomb U_ff electron-electron interactions with respect of the V hybridization of f1 and f2 configurations with the conduction states (i.e. f0 configuration) : we only keep the leading terms in a development in successive powers of 1/U_ff and V. Our numerical results on the magnetic susceptibility start from a simple analytic expression and are discussed in terms of the f level position, the hybridization V, the shape and filling of the conduction band and also the finite U_ff effects. Finally we present calculated curves for the susceptibility versus V in connection with the αγ transition of cerium and utilizing the same parameters as those used previously to obtain core level LIII absorption spectra : also in the case of the susceptibility, the hybridization appears to be an important parameter to describe the phase change from γ to α cerium. Nous utilisons le modèle d'Anderson à une impureté dans l'approximation des grands N_f où N_f est la dégénérescence d'orbitale et de spin du niveau f et nous calculons alors la susceptibilité paramagnétique statique (à température nulle) dans les systèmes métalliques de terres rares légères. Nous effectuons notre calcul pour des valeurs de l'interaction de Coulomb U_ff grandes par rapport à l'hybridation V des configurations f1 et f2 avec les états de conduction (c.-à-d. la configuration f0): nous ne retenons que les termes les plus imporatnts dans un développement en puissances successives de 1/U_ff et V. Ensuite nous discutons nos résultats numériques à partir d'une forme analytique simple obtenue pour la susceptibilité magnétique en fonction de la position du niveau f, de l'hybridation V, de la forme et du

  16. Detection of the pedogenic magnetic fraction in volcanic soils developed on basalts using frequency-dependent magnetic susceptibility: comparison of two instruments

    NASA Astrophysics Data System (ADS)

    Grison, Hana; Petrovsky, Eduard; Kapicka, Ales; Hanzlikova, Hana

    2017-01-01

    SUMMARYIn studies of the <span class="hlt">magnetic</span> properties of soils, the frequency-dependent <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> percentage (χFD%) is often used for the identification of ultrafine <span class="hlt">magnetically</span> superparamagnetic/stable single-domain (SP/SSD) particles. This parameter is commonly used as an indicator for increased pedogenesis. In strongly <span class="hlt">magnetic</span> soils, the SP/SSD <span class="hlt">magnetic</span> signal (mostly bio-pedogenic) may be masked by lithological signals; making pedogenesis hard to detect. In this study we compare results for the detection of ultrafine SP/SSD <span class="hlt">magnetic</span> particles in andic soils using two instruments: a Bartington MS2B dual-frequency meter and an AGICO Kappabridge MFK1-FA. In particular, the study focuses on the effect of pedogenesis by investigating the relationship between specific soil <span class="hlt">magnetic</span> and chemical properties (soil organic carbon and pHH2O). The values of χFD% obtained with the MS2B varied from 2.4 to 5.9%, and mass-specific <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (χLF) from 283 to 1688 × 10-8 m3 kg-1, while values of χFD% and χLF obtained with the MFK1-FA varied from 2.7 to 8.2% and from 299 to 1859 × 10-8 m3 kg-1, respectively. Our results suggest that the detection of the SP/SSD <span class="hlt">magnetic</span> fraction can be accomplished by comparing relative trends of χFD% along the soil profile. Moreover, the discrimination between bio-pedogenic and lithogenic <span class="hlt">magnetic</span> contributions in the SP/SSD fraction is possible by comparing the χFD% and χLF data determined in the fine earth (<2 mm) and the coarse fraction (4-10 mm) samples down the soil profile.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JMMM..418..169K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JMMM..418..169K"><span><span class="hlt">Magnetization</span> and <span class="hlt">susceptibility</span> of a parabolic InAs quantum dot with electron-electron and spin-orbit interactions in the presence of a <span class="hlt">magnetic</span> field at finite temperature</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kumar, D. Sanjeev; Mukhopadhyay, Soma; Chatterjee, Ashok</p> <p>2016-11-01</p> <p>The <span class="hlt">magnetization</span> and <span class="hlt">susceptibility</span> of a two-electron parabolic quantum dot are studied in the presence of electron-electron and spin-orbit interactions as a function of <span class="hlt">magnetic</span> field and temperature. The spin-orbit interactions are treated by a unitary transformation and an exactly soluble parabolic interaction model is considered to mimic the electron-electron interaction. The theory is finally applied to an InAs quantum dot. <span class="hlt">Magnetization</span> and <span class="hlt">susceptibility</span> are calculated using canonical ensemble approach. Our results show that Temperature has no effect on <span class="hlt">magnetization</span> and <span class="hlt">susceptibility</span> in the diamagnetic regime whereas electron-electron interaction reduces them. The temperature however reduces the height of the paramagnetic peak. The Rashba spin-orbit interaction is shown to shift the paramagnetic peak towards higher <span class="hlt">magnetic</span> fields whereas the Dresselhaus spin-orbit interaction shifts it to the lower <span class="hlt">magnetic</span> field side. Spin-orbit interaction has no effect on <span class="hlt">magnetization</span> and <span class="hlt">susceptibility</span> at larger temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhLB..767..278L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhLB..767..278L"><span>Hyperscaling violating solutions in <span class="hlt">generalised</span> EMD theory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Li</p> <p>2017-04-01</p> <p>This short note is devoted to deriving scaling but hyperscaling violating solutions in a <span class="hlt">generalised</span> Einstein-Maxwell-Dilaton theory with an arbitrary number of scalars and vectors. We obtain analytic solutions in some special case and discuss the physical constraints on the allowed parameter range in order to have a well-defined holographic ground-state solution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SedG..351...80D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SedG..351...80D"><span>Stratigraphic correlations in mid- to late-Proterozoic carbonates of the Democratic Republic of Congo using <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Delpomdor, Franck R. A.; Devleeschouwer, Xavier; Spassov, Simo; Préat, Alain R.</p> <p>2017-04-01</p> <p>In this paper, we have tested the application of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements in Cu-Ag-Zn-Pb-(Fe)-mineralized carbonates of the BIe subgroup (Democratic Republic of Congo) as an efficient tool for regional and global high-resolution stratigraphic correlations in the Neoproterozoic marine carbonates. To achieve this goal, we integrate the low-field <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (XLF) data with facies analyses, geochemistry and isotope stratigraphy. The microfacies analyses of two cores, Tshinyama#S70 and Kafuku#15, drilled in the early Neoproterozoic carbonates of the Mbuji-Mayi Supergroup reveal a deep carbonate ramp setting associated with a microbial/stromatolitic mid-ramp environment. High-resolution stratigraphic correlations using <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and C-isotope curves established for both cores, 190 km apart, suggest a sedimentary hiatus at the base of the Tshinyama#S70 succession. C-O and Sr isotopes and Sr/Ca and Fe abundances show that a diagenetic meteoric overprint affected the series of the Tshinyama#S70 core and a thermal effect related to mineralizing fluids affected the Kafuku#15 core carbonates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22413482','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22413482"><span>Detection of microcalcifications by characteristic <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> effects using MR phase image cross-correlation analysis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Baheza, Richard A.; Welch, E. Brian; Gochberg, Daniel F.; Sanders, Melinda; Harvey, Sara; Gore, John C.; Yankeelov, Thomas E.</p> <p>2015-03-15</p> <p>Purpose: To develop and evaluate a new method for detecting calcium deposits using their characteristic <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> effects on <span class="hlt">magnetic</span> resonance (MR) images at high fields and demonstrate its potential in practice for detecting breast microcalcifications. Methods: Characteristic dipole signatures of calcium deposits were detected in <span class="hlt">magnetic</span> resonance phase images by computing the cross-correlation between the acquired data and a library of templates containing simulated phase patterns of spherical deposits. The influence of signal-to-noise ratio and various other MR parameters on the results were assessed using simulations and validated experimentally. The method was tested experimentally for detection of calcium fragments within gel phantoms and calcium-like inhomogeneities within chicken tissue at 7 T with optimized MR acquisition parameters. The method was also evaluated for detection of simulated microcalcifications, modeled from biopsy samples of malignant breast cancer, inserted in silico into breast <span class="hlt">magnetic</span> resonance imaging (MRIs) of healthy subjects at 7 T. For both assessments of calcium fragments in phantoms and biopsy-based simulated microcalcifications in breast MRIs, receiver operator characteristic curve analyses were performed to determine the cross-correlation index cutoff, for achieving optimal sensitivity and specificity, and the area under the curve (AUC), for measuring the method’s performance. Results: The method detected calcium fragments with sizes of 0.14–0.79 mm, 1 mm calcium-like deposits, and simulated microcalcifications with sizes of 0.4–1.0 mm in images with voxel sizes between (0.2 mm){sup 3} and (0.6 mm){sup 3}. In images acquired at 7 T with voxel sizes of (0.2 mm){sup 3}–(0.4 mm){sup 3}, calcium fragments (size 0.3–0.4 mm) were detected with a sensitivity, specificity, and AUC of 78%–90%, 51%–68%, and 0.77%–0.88%, respectively. In images acquired with a human 7 T scanner, acquisition times below 12</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGP21A3645S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGP21A3645S"><span>Paleomagnetism and Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> study of the Miocene Jack Springs Tuff (Nevada, USA)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shields, S.; Petronis, M. S.; Pluhar, C. J.; Gordon, L.</p> <p>2014-12-01</p> <p>The mid-Miocene Jack Springs Tuff (JST) outcrops across the western Mina Deflection accommodation zone, west-central Nevada and into eastern California. Previously, the source location for the JST was unknown, yet recent studies northwest of Mono Lake, CA have identified a relatively un-rotated structural block in which to reference the paleomagnetic data. Although new studies have indicated that this block may be rotated up to 13º, we argue that the probable source area is located near the Bodie Hills, CA. At this site, the paleomagnetic reference direction is D = 353°, I = 43°, α95 = 7.7° (Carlson et al, 2013). Based on these data, the JST can be used to measure absolute vertical-axis rotation as well as enable reconstruction of the paleo-topography using the corrected anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) data. A total of 19 sites were sampled to constrain Cenozoic to recent vertical axis rotation within the region and AMS experiments were conducted to determine the flow direction of the JST. Curie point estimates indicate that the JST ranges in titanium concentration from 0.042 to 1.10, indicating a low to moderate titanomagnetite phase (Akimoto, 1962). Demagnetization experiments reveal mean destructive fields of the NRM ranging between 15mT and 40mT suggesting that both multi-domain to pseudo-single domain grains are the dominant ferromagnetic phases that carry the remanence and AMS fabric. Preliminary paleomagnetic data yield stable single component demagnetization behavior for most sites that, after structural correction, indicate clockwise vertical axis rotation ranging from +20°± 10° to +60°± 11° between multiple fault blocks. The uncorrected AMS data yield oblate <span class="hlt">magnetic</span> fabrics that can be used to infer the transport direction, source region, and paleovalley geometry of the JST. These data are tentatively interpreted to indicate west to east transport of the JST across the Mono Basin region into the Mina Deflection that was erupted and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70033068','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70033068"><span>Soil <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>: A quantitative proxy of soil drainage for use in ecological restoration</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Grimley, D.A.; Wang, J.-S.; Liebert, D.A.; Dawson, J.O.</p> <p>2008-01-01</p> <p>Flooded, saturated, or poorly drained soils are commonly anaerobic, leading to microbially induced magnetite/maghemite dissolution and decreased soil <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS). Thus, MS is considerably higher in well-drained soils (MS typically 40-80 ?? 10-5 standard international [SI]) compared to poorly drained soils (MS typically 10-25 ?? 10-5 SI) in Illinois, other soil-forming factors being equal. Following calibration to standard soil probings, MS values can be used to rapidly and precisely delineate hydric from nonhydric soils in areas with relatively uniform parent material. Furthermore, soil MS has a moderate to strong association with individual tree species' distribution across soil moisture regimes, correlating inversely with independently reported rankings of a tree species' flood tolerance. Soil MS mapping can thus provide a simple, rapid, and quantitative means for precisely guiding reforestation with respect to plant species' adaptations to soil drainage classes. For instance, in native woodlands of east-central Illinois, Quercus alba , Prunus serotina, and Liriodendron tulipifera predominantly occur in moderately well-drained soils (MS 40-60 ?? 10-5 SI), whereas Acer saccharinum, Carya laciniosa, and Fraxinus pennsylvanica predominantly occur in poorly drained soils (MS <20 ?? 10-5 SI). Using a similar method, an MS contour map was used to guide restoration of mesic, wet mesic, and wet prairie species to pre-settlement distributions at Meadowbrook Park (Urbana, IL, U.S.A.). Through use of soil MS maps calibrated to soil drainage class and native vegetation occurrence, restoration efforts can be conducted more successfully and species distributions more accurately reconstructed at the microecosystem level. ?? 2008 Society for Ecological Restoration International.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SedG..230...77L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SedG..230...77L"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> variations and provenance of surface sediments in the South China Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Jianguo; Chen, Zhong; Chen, Muhong; Yan, Wen; Xiang, Rong; Tang, Xianzan</p> <p>2010-10-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (MS) and grain sizes of surface sediments are measured to characterize sediment sources and their distribution in the South China Sea (SCS). Distribution characteristics of MS of bulk samples (MSB), fine-grained fraction (MSF) and coarse-grained fraction (MSC) are examined to explore the factors affecting MS values in sediment transport and deposition processes. Affected by dilution of quartz and carbonate abundance, MSC is not suitable for tracing sediment sources in the region. Instead, MSF provides a good parameter for tracking transport and deposition of complex and coarse-grained sediments such as those from Luzon Island volcanics and from the Pearl and Mekong Rivers, which often have high MSF values showing a decreasing trend with water depth on the continental shelf (water depth < 200 m). To the west of Luzon Island, Kuroshio intrusion into the SCS is the predominant factor for sediment transport after high MSF volcanic materials from the Luzon Island are discharged into the sea. Sediments from the Pearl River are transported southwestward under the China coastal current and then deposited between the Pearl River mouth and Hainan Island. To the southwest of Taiwan Island in the northeastern SCS, where sediments are mainly derived from Taiwan Island and/or the Yangtze River, both the Kuroshio intrusion and the China coastal current are significant in determining sediment transport and deposition. In the south, most of high MSF sediments from the Mekong River are transported eastward under the influence of northeastward currents in summer after entering the sea and then deposited on the northern Sunda Shelf.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18984068','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18984068"><span><span class="hlt">Magnetic</span> resonance imaging method based on <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> effects to estimate bubble size in alveolar products: application to bread dough during proving.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>De Guio, François; Musse, Maja; Benoit-Cattin, Hugues; Lucas, Tiphaine; Davenel, Armel</p> <p>2009-05-01</p> <p><span class="hlt">Magnetic</span> resonance imaging has proven its potential application in bread dough and gas cell monitoring studies, and dynamic processes such as dough proving and baking can be monitored. However, undesirable <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> effects often affect quantification studies, especially at high fields. A new low-field method is presented based on local assessment of porosity in spin-echo imaging, local characterization of signal loss in gradient-echo imaging and prediction of relaxation times by simulation to estimate bubble radii in bread dough during proving. Maps of radii showed different regions of dough constituting networks which evolved during proving. Mean radius and bubble distribution were assessed during proving.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JSG....27.1750E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JSG....27.1750E"><span>Deformation regime variations in an arcuate transpressional orogen (Ribeira belt, SE Brazil) imaged by anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> in granulites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Egydio-Silva, Marcos; Vauchez, Alain; Raposo, Maria Irene B.; Bascou, Jérôme; Uhlein, Alexandre</p> <p>2005-10-01</p> <p>The Ribeira belt of southeastern Brazil displays an arcuate shape, with a structural trend that varies from ˜NS in the northern domain to ENE-WSW in the southern domain. This curvature is accompanied by a transition from contraction-dominated to transcurrent-dominated tectonics. The transition in deformation regime is accommodated in the central domain of the belt where granulitic rocks dominate and mineral-stretching lineations are commonly concealed by metamorphic recrystallization. We present anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) data from 664 samples from 62 sites in high-temperature gneisses, granulites and migmatites of the transitional, central domain of the belt, with the aim of investigating: (1) how well AMS allows one to map the mineral-stretching lineation and foliations in domains displaying a complex kinematic framework and (2) to investigate the kinematic pattern at the transition between the thrusting dominated and a wrench-faulting dominated orogenic segments. The mean <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> is 7.54×10 -3 SI. The degree of anisotropy varies from 1.32 up to 4.31, with an average value of 1.53. The shape parameter T is generally >0 meaning that the AMS ellipsoid is dominantly oblate. <span class="hlt">Magnetic</span> lineations and foliations form a consistent pattern correlated with the modification of the structural characteristics observed along the Ribeira belt. In the southern wrench-fault-dominated domain, the <span class="hlt">magnetic</span> lineation is subhorizontal, parallel to the trend of the steeply dipping <span class="hlt">magnetic</span> foliation. This correlation with the fabric observed in mylonites suggests that the <span class="hlt">magnetic</span> fabric is a valid proxy of the tectonic fabric in granulites. Results from the northern domain show that it comprises two sub-domains both displaying a ˜NS-trending <span class="hlt">magnetic</span> foliation. Eastward, over a broad area, the <span class="hlt">magnetic</span> foliation is consistently steeply dipping and bears a shallowly to moderately plunging <span class="hlt">magnetic</span> lineation. Westward, the dip of the foliation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6217E..01D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6217E..01D"><span>Time-domain response of a metal detector to a target buried in soil with frequency-dependent <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Das, Y.</p> <p>2006-05-01</p> <p>The work reported in this paper is a part of on-going studies to clarify how and to what extent soil electromagnetic properties affect the performance of induction metal detectors widely used in humanitarian demining. This paper studies the specific case of the time-domain response of a small metallic sphere buried in a non-conducting soil half-space with frequency-dependent complex <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>. The sphere is chosen as a simple prototype for the small metal parts in low-metal landmines, while soil with dispersive <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> is a good model for some soils that are known to adversely affect the performance of metal detectors. The included analysis and computations extend previous work which has been done mostly in the frequency domain. Approximate theoretical expressions for weakly <span class="hlt">magnetic</span> soils are found to fit the experimental data very well, which allowed the estimation of soil model parameters, albeit in an ad hoc manner. Soil signal is found to exceed target signal (due to an aluminum sphere of radius 0.0127 m) in many cases, even for the weakly <span class="hlt">magnetic</span> Cambodian laterite used in the experiments. How deep a buried target is detected depends on many other factors in addition to the relative strength of soil and target signals. A general statement cannot thus be made regarding detectability of a target in soil based on the presented results. However, computational results complemented with experimental data extend the understanding of the effect that soil has on metal detectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhA...49s5201G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhA...49s5201G"><span>Quantum mechanics of a <span class="hlt">generalised</span> rigid body</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gripaios, Ben; Sutherland, Dave</p> <p>2016-05-01</p> <p>We consider the quantum version of Arnold’s <span class="hlt">generalisation</span> of a rigid body in classical mechanics. Thus, we quantise the motion on an arbitrary Lie group manifold of a particle whose classical trajectories correspond to the geodesics of any one-sided-invariant metric. We show how the derivation of the spectrum of energy eigenstates can be simplified by making use of automorphisms of the Lie algebra and (for groups of type I) by methods of harmonic analysis. We show how the method can be extended to cosets, <span class="hlt">generalising</span> the linear rigid rotor. As examples, we consider all connected and simply connected Lie groups up to dimension 3. This includes the universal cover of the archetypical rigid body, along with a number of new exactly solvable models. We also discuss a possible application to the topical problem of quantising a perfect fluid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22572334','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22572334"><span>Sequential experimental design based <span class="hlt">generalised</span> ANOVA</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chakraborty, Souvik Chowdhury, Rajib</p> <p>2016-07-15</p> <p>Over the last decade, surrogate modelling technique has gained wide popularity in the field of uncertainty quantification, optimization, model exploration and sensitivity analysis. This approach relies on experimental design to generate training points and regression/interpolation for generating the surrogate. In this work, it is argued that conventional experimental design may render a surrogate model inefficient. In order to address this issue, this paper presents a novel distribution adaptive sequential experimental design (DA-SED). The proposed DA-SED has been coupled with a variant of <span class="hlt">generalised</span> analysis of variance (G-ANOVA), developed by representing the component function using the <span class="hlt">generalised</span> polynomial chaos expansion. Moreover, <span class="hlt">generalised</span> analytical expressions for calculating the first two statistical moments of the response, which are utilized in predicting the probability of failure, have also been developed. The proposed approach has been utilized in predicting probability of failure of three structural mechanics problems. It is observed that the proposed approach yields accurate and computationally efficient estimate of the failure probability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JCoPh.317...15C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JCoPh.317...15C"><span>Sequential experimental design based <span class="hlt">generalised</span> ANOVA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chakraborty, Souvik; Chowdhury, Rajib</p> <p>2016-07-01</p> <p>Over the last decade, surrogate modelling technique has gained wide popularity in the field of uncertainty quantification, optimization, model exploration and sensitivity analysis. This approach relies on experimental design to generate training points and regression/interpolation for generating the surrogate. In this work, it is argued that conventional experimental design may render a surrogate model inefficient. In order to address this issue, this paper presents a novel distribution adaptive sequential experimental design (DA-SED). The proposed DA-SED has been coupled with a variant of <span class="hlt">generalised</span> analysis of variance (G-ANOVA), developed by representing the component function using the <span class="hlt">generalised</span> polynomial chaos expansion. Moreover, <span class="hlt">generalised</span> analytical expressions for calculating the first two statistical moments of the response, which are utilized in predicting the probability of failure, have also been developed. The proposed approach has been utilized in predicting probability of failure of three structural mechanics problems. It is observed that the proposed approach yields accurate and computationally efficient estimate of the failure probability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1335307','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1335307"><span>Single crystal <span class="hlt">magnetic</span> structure and <span class="hlt">susceptibility</span> of CoSe<sub>2</sub>O<sub>5</sub></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rodriguez, Efrain E.; Cao, Huibo; Haiges, Ralf; Melot, Brent C.</p> <p>2015-09-08</p> <p>The structure of CoSe<sub>2</sub>O<sub>5</sub> consists of one-dimensional ribbons of edge-sharing CoO<sub>6</sub> octahedra bound together by polyanionic subunits of Se<sub>2</sub>O<sub>5</sub>. Previous work on polycrystalline samples reported a canted antiferromagnetic arrangement of the <span class="hlt">magnetic</span> moments below the ordering temperature of 8.5 K. Here, we report a single crystal investigation using variable temperature and field <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and low-temperature neutron diffraction to more precisely characterize the nature of the <span class="hlt">magnetic</span> ground state of CoSe<sub>2</sub>O<sub>5</sub>. Contrary to previous reports, we find that the single crystal <span class="hlt">magnetic</span> structure shows no canting of the antiferromagnetic ground state, and in the process have identified several field-induced changes to the <span class="hlt">magnetization</span>. Lastly, we discuss these results in the context of the revised <span class="hlt">magnetic</span> structure and highlight the importance of crystal growth for the accurate characterization of these properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMGP23A..05W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMGP23A..05W"><span>The Latitudinal Gradient of Rainfall, Mineralogy, Albedo and <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> in West Africa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, E. R.; Balsam, W.; Schaaf, C.; Yang, X.; Zhang, Q.; Ji, J.; Rossman, G.; Garimella, S.; Oldfield, F.; Lyons, J. R.; Ellwood, B.; Hartman, H.; Hicks, E.; Mansot, J. L.; Cesaire, T.; Thomas, P.</p> <p>2008-12-01</p> <p>In order to investigate the effect of climate on soil and surface sediment properties we examined four transects around the Sahara Desert. The transects were located in Mali, Niger, Benin, Togo, Egypt and Morocco and, with the exception of Egypt, each crossed a significant climatological rainfall gradient. The Egyptian transect was designed to characterize one of the driest portions of the Sahara Desert. Our study included laboratory measurements of mineralogy (XRD), elemental composition (XRF), grain size, optical reflectance (lab), <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS)and remanences. In addition, albedo was determined from the MODIS satellite imagery from space. Many of our laboratory measurements exhibited variations with the rainfall gradient. Iron oxides (hematite and goethite), kaolinite, Al2O3, and TiO2 increased with increasing rainfall whereas SiO2, illite, and grain size decreased with increasing rainfall. Both laboratory-determined reflectivity and satellite-determine albedo decreased as rainfall increased. In part, this decrease in reflectivity/albedo with increasing rainfall appears to be the result of hematite, the dominant coloring agent for the soil in this region and the origin of the 'red' Sahel. The physical interpretation of these results centers on rainfall as a long-term leaching agent of surface material, and the control of physical properties by specific mineralogy. SiO2 is highly reflective and iron oxides are strongly absorptive in the visible range. The solubility of SiO2 in rainwater is orders of magnitude larger than all the iron oxides, with hematite the least soluble. It has long been recognized that leaching by rainfall produces dark red laterite in the near-surface oxidizing environment, a prominent geological feature throughout the high rainfall belt of West Africa. Laterite beds represent simultaneous enrichments of all iron oxides and a reduction in SiO2 by leaching. In the Sahara desert where rainfall is minimal (<10 mm/yr), SiO2 is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5359224','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5359224"><span>Dynamic <span class="hlt">Susceptibility</span> Contrast <span class="hlt">Magnetic</span> Resonance Imaging Protocol of the Normal Canine Brain</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Stadler, Krystina L.; Pease, Anthony P.; Ballegeer, Elizabeth A.</p> <p>2017-01-01</p> <p>Perfusion <span class="hlt">magnetic</span> resonance imaging (MRI), specifically dynamic <span class="hlt">susceptibility</span> MRI (DSC-MRI) is routinely performed as a supplement to conventional MRI in human medicine for patients with intracranial neoplasia and cerebrovascular events. There is minimal data on the use of DSC-MRI in veterinary patients and a DSC-MRI protocol in the veterinary patient has not been described. Sixteen normal dogs, 6 years or older were recruited for this study. The sample population included 11 large dogs (>11 kg) and 5 small dogs (<11 kg). DSC-MRI was performed on a 1.5-T MRI using an adjusted protocol inherent to the MRI. Contrast media was injected using an automatic power injector. Injections were made after five MR measurements were obtained. Following image acquisition, an arterial input function (AIF) graph mapping the transit time of contrast within the cerebral arteries was generated. The manually selected time points along this graph were used to compute perfusion maps. A dose and rate of 0.1 mmol/kg gadolinium-based contrast media at 3 ml/s followed by 10 ml saline flush at 3 ml/s was used in all dogs greater than 11 kg. In all dogs >11 kg, a useable AIF and perfusion map was generated. One dog less than 11 kg received the same contrast dose and rate. In this patient, the protocol did not generate a useable AIF. The remainder of the dogs less than 11 kg followed a protocol of 0.2 mmol/kg gadolinium-based contrast media at 1.5 ml/s with a 10 ml saline flush at 1.5 ml/s. A useable AIF and perfusion map was generated in the remaining dogs <11 kg using the higher contrast dose and slower rate protocol. This study establishes a contrast dose and administration rate for canine DSC-MRI imaging that is different in dogs greater than 11 kg compared to dogs less than 11 kg. These protocols may be used for future applications to evaluate hemodynamic disturbances in canine intracranial pathology. PMID:28377923</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28377923','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28377923"><span>Dynamic <span class="hlt">Susceptibility</span> Contrast <span class="hlt">Magnetic</span> Resonance Imaging Protocol of the Normal Canine Brain.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stadler, Krystina L; Pease, Anthony P; Ballegeer, Elizabeth A</p> <p>2017-01-01</p> <p>Perfusion <span class="hlt">magnetic</span> resonance imaging (MRI), specifically dynamic <span class="hlt">susceptibility</span> MRI (DSC-MRI) is routinely performed as a supplement to conventional MRI in human medicine for patients with intracranial neoplasia and cerebrovascular events. There is minimal data on the use of DSC-MRI in veterinary patients and a DSC-MRI protocol in the veterinary patient has not been described. Sixteen normal dogs, 6 years or older were recruited for this study. The sample population included 11 large dogs (>11 kg) and 5 small dogs (<11 kg). DSC-MRI was performed on a 1.5-T MRI using an adjusted protocol inherent to the MRI. Contrast media was injected using an automatic power injector. Injections were made after five MR measurements were obtained. Following image acquisition, an arterial input function (AIF) graph mapping the transit time of contrast within the cerebral arteries was generated. The manually selected time points along this graph were used to compute perfusion maps. A dose and rate of 0.1 mmol/kg gadolinium-based contrast media at 3 ml/s followed by 10 ml saline flush at 3 ml/s was used in all dogs greater than 11 kg. In all dogs >11 kg, a useable AIF and perfusion map was generated. One dog less than 11 kg received the same contrast dose and rate. In this patient, the protocol did not generate a useable AIF. The remainder of the dogs less than 11 kg followed a protocol of 0.2 mmol/kg gadolinium-based contrast media at 1.5 ml/s with a 10 ml saline flush at 1.5 ml/s. A useable AIF and perfusion map was generated in the remaining dogs <11 kg using the higher contrast dose and slower rate protocol. This study establishes a contrast dose and administration rate for canine DSC-MRI imaging that is different in dogs greater than 11 kg compared to dogs less than 11 kg. These protocols may be used for future applications to evaluate hemodynamic disturbances in canine intracranial pathology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22342939','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22342939"><span>[<span class="hlt">Susceptibility</span> weighted <span class="hlt">magnetic</span> resonance sequences "SWAN, SWI and VenoBOLD": technical aspects and clinical applications].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hodel, J; Rodallec, M; Gerber, S; Blanc, R; Maraval, A; Caron, S; Tyvaert, L; Zuber, M; Zins, M</p> <p>2012-05-01</p> <p><span class="hlt">Susceptibility</span>-weighted MR sequences, T2 star weighted angiography (SWAN, General Electric), <span class="hlt">Susceptibility</span> weighted imaging (SWI, Siemens) and venous blood oxygen level dependant (VenoBOLD, Philips) are 3D spoiled gradient-echo sequence that provide a high sensitivity for the detection of blood degradation products, calcifications, and iron deposits. For all these sequences, an appropriate echo time allows for the visualization of <span class="hlt">susceptibility</span> differences between adjacent tissues. However, each of these sequences presents a specific technical background. The purpose of this review was to describe 1/the technical aspects of SWAN, VenoBOLD and SWI sequences, 2/the differences observed in term of contrast within the images, 3/the key imaging findings in neuroimaging using <span class="hlt">susceptibility</span>-weighted MR sequences.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JSG....34...54B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JSG....34...54B"><span>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) and diamagnetic fabrics in the Durness Limestone, NW Scotland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borradaile, G. J.; Almqvist, B. S. G.; Geneviciene, I.</p> <p>2012-01-01</p> <p>AMS fabrics in the Durness limestone show principal axes with orientations that are counterintuitive to, but symmetrical, with the regional tectonic axes ( X, Y, Z) where X is the stretching axis and Z is the shortening axis. In the field, cleavage ( XY) is nearly NS and nearly vertical. Low-field <span class="hlt">susceptibility</span> measurements of 57 cores with positive bulk <span class="hlt">susceptibility</span> (κ > 0) have a nearly vertical maximum <span class="hlt">susceptibility</span> (κ MAx) that is similarly oriented to the regional extension axis ( X) but with intermediate <span class="hlt">susceptibility</span> approximately parallel to the regional EW shortening axis. We explain this fabric as the blending of an oblate subhorizontal bedding with a north-south feeble tectonic AMS fabric, parallel to the regional N-S vertical cleavage. The 79 diamagnetic ( κ < 0) cores reveal a similar AMS fabric when the orientations of the maximum and minimum axes are exchanged to produce a paramagnetic-compatible fabric.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.4657B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.4657B"><span>Case Study Of Spatial <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> Screening Within The Urban Area Of Tuebingen, SW Germany, As A Proxy For Poly-cyclic Aromatic Hydrocarbon Contamination</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blaha, U.; Steidle, D. K.; Hoffmann, V.; Appel, E.; Grathwohl, P.</p> <p></p> <p>In situ <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> screening was performed in the southern part of Tübin- gen city, SW Germany. The main purpose of this case study was to prove the applica- bility of in situ <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements on soils in a variably polluted and densely populated urban environment. Road and rail traffic, house heating and small-scale industry are regarded as the sources of air-borne pollutants in Tübingen city. The impact of any kind of anthropogenic input on soils was studied taking into account specific areas in the city and the topography. A topographical dependence of in situ <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> as well as Shot spotsT of strongly increased values & cedil;were observed. More detailed investigation on selected spots, measuring the suscepti- bility on vertical soil profiles in the laboratory, provided information about the origin of the recorded <span class="hlt">magnetic</span> signal. Rock <span class="hlt">magnetic</span> measurements provided additional in- formation about the origin of mineral phases in the soils. PAH (Poly-cyclic Aromatic Hydrocarbon) analyses on selected soil samples revealed a direct link to the observed <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> indicating that <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> might be a proxy for PAH contamination in soils.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930022691&hterms=Wais&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DWais','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930022691&hterms=Wais&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DWais"><span>Lithology and chronology of ice-sheet fluctuations (<span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of cores from the western Ross Sea)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jennings, Anne E.</p> <p>1993-01-01</p> <p>The goals of the marine geology part of WAIS include reconstructing the chronology and areal extent of ice-sheet fluctuations and understanding the climatic and oceanographic influences on ice-sheet history. As an initial step toward attaining these goals, down-core volume <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS) logs of piston cores from three N-S transects in the western Ross Sea are compared. The core transects are within separate petrographic provinces based on analyses of till composition. The provinces are thought to reflect the previous locations of ice streams on the shelf during the last glaciation. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> is a function of <span class="hlt">magnetic</span> mineral composition, sediment texture, and sediment density. It is applied in the western Ross Sea for two purposes: (1) to determine whether MS data differentiates the three transects (i.e., flow lines), and thus can be used to make paleodrainage reconstructions of the late Wisconsinan ice sheet; and (2) to determine whether the MS data can aid in distinguishing basal till diamictons from diamictons of glacial-marine origin and thus, aid paleoenvironmental interpretations. A comparison of the combined data of cores in each transect is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18181645','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18181645"><span>Preparation of bovine serum albumin surface-imprinted submicrometer particles with <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> through core-shell miniemulsion polymerization.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tan, Chau Jin; Chua, Hong Gap; Ker, Kwee Hong; Tong, Yen Wah</p> <p>2008-02-01</p> <p>Molecular imprinting is a state-of-the-art technique for preparing mimics of natural, biological receptors. Nevertheless, the imprinting of macromolecules like proteins remains a challenge due to their bulkiness and sensitivity to denaturation. In this work, a surface imprinting strategy based on covalently immobilized template molecules was adopted for protein imprinting. Bovine serum albumin (BSA) surface-imprinted submicrometer particles (500-600 nm) with <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> were prepared through a two-stage core-shell miniemulsion polymerization system using methyl methacrylate and ethylene glycol dimethacrylate as functional and cross-linking monomers, respectively. The particles possessed a novel red blood cell-like structure and exhibited a very favorable recognition property toward the template BSA molecules in aqueous medium. In a two-protein system, the particles had shown a very high specific recognition of the template proteins over the nontemplate proteins. The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> was imparted through the successful encapsulation of Fe3O4 nanoparticles. Their superparamagnetic nature increases their potential applications in the fields such as <span class="hlt">magnetic</span> bioseparation, cell labeling, and bioimaging. In addition, the importance of template immobilization for successful protein imprinting had also been illustrated to demonstrate the potential of this approach as a general methodology for protein imprinting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760014990','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760014990"><span><span class="hlt">Magnetization</span> and <span class="hlt">magnetic</span> <span class="hlt">susceptibilities</span> of GdH3, HoH3, ErH3 and YbH3</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Flood, D. J.</p> <p>1976-01-01</p> <p>The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of powdered samples of HoH3, ErH3, GdH3 and YbH3 have been measured in the temperature range from 4.2 to 1.2 K. Two broad, local maxima are observed in the variation of chi versus T for GdH3, with maxima in (delta chi delta T) versus T at 1.8 K and 3.3 K. The inverse <span class="hlt">susceptibilities</span> for HoH3 and ErH3 both obey a Curies-Weiss law over a limited range (4.2 to 2.6K and 4.2 to 2 K respectively) with values for the Weiss constant of -4.25 K and -1.11 K, and effective moments of 8.6 and 7.7 Bohr magnetons respectively. The <span class="hlt">susceptibility</span> of YbH3 is independent of temperature over the range investigated. High-field <span class="hlt">magnetization</span> measurements yield extrapolated saturation moments of 7.0 + or - 0.25 Bohr magnetons/ion for GdH3, 6.1 + or - 0.2 Bohr magnetons/ion for HoH3 and 3.74 + or - 0.11 Bohr magnetons/ion for ErH3. In addition, ErH3 exhibits a van Vleck paramagnetism in the high field region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Tectp.656..175I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Tectp.656..175I"><span>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> in diamagnetic limestones reveals deflection of the strain field near the Dead Sea Fault, northern Israel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Issachar, R.; Levi, T.; Marco, S.; Weinberger, R.</p> <p>2015-08-01</p> <p>To exploit the potential of anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) as a tool to estimate the strain field around major faults, we measured the AMS of calcite-bearing diamagnetic rocks that crop out next to the Dead Sea Fault (DSF) in northern Israel. Through integrated <span class="hlt">magnetic</span> and geochemical methods we found that the rocks are almost pure calcite rocks and therefore the <span class="hlt">magnetic</span> fabric is primarily controlled by preferred crystallographic orientation (PCO) with the minimum principal AMS axes (k3) parallel to calcite c-axes. We applied a separation procedure in several samples with high Fe content in order to calculate the AMS anisotropy parameters and compare them to pure diamagnetic rocks. AARM, thermo-<span class="hlt">susceptibility</span> curves and IRM were used to characterize the <span class="hlt">magnetic</span> phases. We found that for Fe content below 500 ppm the AMS is mostly controlled by the diamagnetic phase and showed that differences in the degree of anisotropy P' up to 3% (P' = 1.005 to 1.023) and in anisotropy difference Δk (up to ~ 0.25 × 10- 6 SI) in diamagnetic rocks are related to differences of strain magnitudes. The spatial distribution of the <span class="hlt">magnetic</span> fabrics indicates ~ N-S maximum shortening parallel to the strike of the Hula Western Border fault (HWBF), one of the main strands of the DSF in northern Israel. The anisotropy parameters suggest that the strain magnitudes increase eastward with the proximity to the HWBF. These results suggest that the strain field near the HWBF is locally deflected as a consequence of the DSF activity. In light of the "fault weakness" model and geological setting of the study area, we suggest that the area accommodates dominant transtension during the Pleistocene. The present study demonstrates the useful application of AMS measurements in "iron-free" limestones as recorders of the strain field near plate boundaries.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUSMMA11B..03M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUSMMA11B..03M"><span>Measurement of Meteorite Density, Porosity and <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span>: Fast, Non- destructive, Non-contaminating and Very Informative</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Macke, R. J.; Britt, D. T.; Consolmagno, G. J.</p> <p>2009-05-01</p> <p>The development of the "glass bead" method [1] for measuring bulk density, coupled with other fast, non- destructive and non-contaminating methods for measuring grain density and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, has enabled broad surveys of large meteorite collections. We have employed these methods extensively on meteorites in numerous collections, including those at the Vatican, the American Museum of Natural History (New York), the National Museum of Natural History (Washington, DC), Texas Christian University, University of New Mexico, and Arizona State University. We present here a summary of some of the findings to date. Using the glass bead method, the meteorite is placed into a container which is then filled entirely with small (sub- millimeter) glass beads. The beads behave collectively as an Archimedean fluid, flowing around the sample to fill the empty space in the container. Through mass measurement, the volume displaced by the sample can be determined. Grain density is determined via helium ideal-gas pycnometry. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> is determined using a commercially available hand-held device [2]. Among notable findings to date, grain density and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> together can distinguish H, L and LL ordinary chondrite falls into clearly distinct groupings [3]. On the other hand, enstatite chondrites of EH and EL subgroups are indistinguishable in these properties, indicating that EH and EL do not differ significantly in iron content [4]. Carbonaceous chondrites can have porosities that are significantly higher than ordinary chondrites and (especially for aqueously altered meteorites) lower density, though these also vary according to subgroups [5]. References: [1] Consolmagno and Britt, 1998. M&PS 33, 1231-1240. [2] Gattacceca et al., 2004. GJI 158, 42-49. [3] Consolmagno et al., 2006. M&PS 41, 331-342. [4] Macke et al., 2009. LPSC 40, 1598. [5] Consolmagno et al., 2008. MetSoc 71, 5038.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AIPC.1591.1410M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AIPC.1591.1410M"><span><span class="hlt">Magnetic</span> field induced third order <span class="hlt">susceptibility</span> of third order harmonic generation in a ZnMgSe strained quantum well</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mark, J. Abraham Hudson; Peter, A. John</p> <p>2014-04-01</p> <p>Third order <span class="hlt">susceptibility</span> of third order harmonic generation is investigated in a Zn0.1Mg0.9Se/Zn0.8Mg0.2Se/Zn0.1Mg0.9Se quantum well in the presence of <span class="hlt">magnetic</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22269321','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22269321"><span><span class="hlt">Magnetic</span> field induced third order <span class="hlt">susceptibility</span> of third order harmonic generation in a ZnMgSe strained quantum well</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mark, J. Abraham Hudson Peter, A. John</p> <p>2014-04-24</p> <p>Third order <span class="hlt">susceptibility</span> 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 <span class="hlt">magnetic</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JMoSt1123..394W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JMoSt1123..394W"><span>Two novel CPs with double helical chains based rigid tripodal ligands: Syntheses, crystal structures, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and fluorescence properties</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Xiao; Hou, Xiang-Yang; Zhai, Quan-Guo; Hu, Man-Cheng</p> <p>2016-11-01</p> <p>Two three-dimensional coordination polymers (CPs), namely [Cd(bpydb)- (H2bpydb)]n·0.5nH2O (1), and [Cu2(bpydb)2]n (2) (2,6-di-p-carboxyphenyl-4,4'- bipyridine1 = H2bpydb), containing a novel double-helical chains, which have been solvothermal synthesized, characterized, and structure determination. CPs 1-2 reveal the new (3,5)-net and (3,6)-net alb topology, respectively. The fluorescence properties of CPs 1-2 were investigated, and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements indicate that compound 1 has dominating antiferromagnetic couplings between metal ions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004JChPh.120.2382D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004JChPh.120.2382D"><span>On the variation of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of a molecular crystal with temperature: The 2,4,6-triphenylverdazyl system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Datta, Sambhu N.; Navada, Geetha K.</p> <p>2004-02-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibilities</span> of spin-1/2 systems of orthorhombic and higher crystal symmetries have been numerically investigated while taking possible anisotropy in the coupling constants along different crystal axes into account. The work relies on the magnon-based theory of ferromagnetic (FM) and antiferromagnetic (AFM) crystal systems of types FFF, AFF, AAF, and AAA [J. Chem. Phys. 111, 9009 (1999)]. The AAF crystal, in particular, shows interesting changes in the temperature dependence of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> when the ferromagnetic exchange coupling constant is varied. We especially show that the <span class="hlt">susceptibility</span> anomalies of molecular crystals fit naturally within the framework of the extended magnon-theoretical formalism, and do not necessarily imply a FM→AFM or a reverse phase transition. A real system, molecular crystal of 2,4,6-triphenylverdazyl (2,4,6-TPV), has been investigated here. It was previously interpreted as an AAF system from observed <span class="hlt">susceptibility</span> data [Tomiyoshi et al., Phys. Rev. B 49, 16031 (1994)]. The trend of the temperature dependence of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> studied in the present work also indicates that the crystal belongs to the AAF category with a less prominent FM exchange coupling constant. To reinforce our conclusions, we have adopted a two-pronged strategy. First, the geometry of the 2,4,6-TPV monomer has been optimized here by ab initio unrestricted Hartree-Fock (UHF) calculations using the STO-3G basis set. The optimized geometry is almost planar. A subsequent calculation has been carried out with the phenyl rings twisted out of the plane of the nitrogen atoms. The STO-3G optimized geometry, and the same geometry except for the twisted phenyl rings, have been used to perform ab initio coupled-cluster (UCCSD-T) calculations with the same basis, and UHF as well as density-functional (UB3LYP) calculations using the 6-31G basis set. The calculated data can easily rationalize the twists while the species remains in crystal. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP21C2262M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP21C2262M"><span><span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> and Geochemistry Records in the Yax-1 Borehole in the Chicxulub Impact Crater: A paleoclimatic approach in the K/Pg and P/E Boundaries.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marca-Castillo, M.; Perez-Cruz, L. L.; Fucugauchi, J. U.; Buitrón Sánchez, B. E.</p> <p>2015-12-01</p> <p>Chicxulub impact crater is located in the northwestern sector of Yucatan Peninsula, Mexico. It is the best-preserved multi-ring impact crater on Earth. Several studies have been focused in this crater structure due its association with the Cretaceous/Paleogenous boundary events. The aim of this study is document the abrupt climate changes during the K/Pg and P/E boundaries based on the stratigraphy, <span class="hlt">magnetic</span> properties (<span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>) and geochemical (major elements) records in the Yaxcopoil-1 (Yax-1) borehole in the Chicxulub impact crater. The Yax 1 was drilled at 20° 44' 38.45'' N, 89° 43' 6.70'' W. Two intervals from 830 to 750 and between 750 and 700 m depth were selected for this study. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> logs and X-Ray Fluorescence (XRF) measures were taken every 10 cm using a Bartington <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> meter and a Thermo Scientific Niton XL3tGOLDD XRF analyzer. Results show variations in <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> logs and major elements (Ca, Si, Fe, Ti and Si) content in the K/Pg boundary at ca. 794 m depth. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> decrease abruptly, Ca values increase, and the other elements show low values. Geochemical results, manly the Ca-record, suggest that the P/E boundary might have happened around 745 m depth. These values are compared with 13C isotopes and they coincide with the Carbon Isotope Excursion (CIE), suggesting their relationship with the abrupt climate change and with the ocean acidification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9783E..57S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9783E..57S"><span>Quantitative evaluation of <span class="hlt">susceptibility</span> effects caused by dental materials in head <span class="hlt">magnetic</span> resonance imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Strocchi, S.; Ghielmi, M.; Basilico, F.; Macchi, A.; Novario, R.; Ferretti, R.; Binaghi, E.</p> <p>2016-03-01</p> <p>This work quantitatively evaluates the effects induced by <span class="hlt">susceptibility</span> characteristics of materials commonly used in dental practice on the quality of head MR images in a clinical 1.5T device. The proposed evaluation procedure measures the image artifacts induced by <span class="hlt">susceptibility</span> in MR images by providing an index consistent with the global degradation as perceived by the experts. <span class="hlt">Susceptibility</span> artifacts were evaluated in a near-clinical setup, using a phantom with <span class="hlt">susceptibility</span> and geometric characteristics similar to that of a human head. We tested different dentist materials, called PAL Keramit, Ti6Al4V-ELI, Keramit NP, ILOR F, Zirconia and used different clinical MR acquisition sequences, such as "classical" SE and fast, gradient, and diffusion sequences. The evaluation is designed as a matching process between reference and artifacts affected images recording the same scene. The extent of the degradation induced by <span class="hlt">susceptibility</span> is then measured in terms of similarity with the corresponding reference image. The matching process involves a multimodal registration task and the use an adequate similarity index psychophysically validated, based on correlation coefficient. The proposed analyses are integrated within a computer-supported procedure that interactively guides the users in the different phases of the evaluation method. 2-Dimensional and 3-dimensional indexes are used for each material and each acquisition sequence. From these, we drew a ranking of the materials, averaging the results obtained. Zirconia and ILOR F appear to be the best choice from the <span class="hlt">susceptibility</span> artefacts point of view, followed, in order, by PAL Keramit, Ti6Al4V-ELI and Keramit NP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21399269','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21399269"><span>Static <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, crystal field and exchange interactions in rare earth titanate pyrochlores.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Malkin, B Z; Lummen, T T A; van Loosdrecht, P H M; Dhalenne, G; Zakirov, A R</p> <p>2010-07-14</p> <p>The experimental temperature dependence (T = 2-300 K) of single crystal bulk and site <span class="hlt">susceptibilities</span> of rare earth titanate pyrochlores R(2)Ti(2)O(7) (R = Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb) is analyzed in the framework of crystal field theory and a mean field approximation. Analytical expressions for the site and bulk <span class="hlt">susceptibilities</span> of the pyrochlore lattice are derived taking into account long range dipole-dipole interactions and anisotropic exchange interactions between the nearest neighbor rare earth ions. The sets of crystal field parameters and anisotropic exchange coupling constants have been determined and their variations along the lanthanide series are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhLB..766...55C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhLB..766...55C"><span><span class="hlt">Generalising</span> the coupling between spacetime and matter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carloni, Sante</p> <p>2017-03-01</p> <p>We explore the idea that the coupling between matter and spacetime is more complex than the one originally envisioned by Einstein. We propose that such coupling takes the form of a new fundamental tensor in the Einstein field equations. We then show that the introduction of this tensor can account for dark phenomenology in General Relativity, maintaining a weak field limit compatible with standard Newtonian gravitation. The same paradigm can be applied any other theory of gravitation. We show, as an example, that in the context of conformal gravity a <span class="hlt">generalised</span> coupling is able to solve compatibility issues between the matter and the gravitational sector.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Tecto..33.2526P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Tecto..33.2526P"><span>The curved Magallanes fold and thrust belt: Tectonic insights from a paleomagnetic and anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Poblete, F.; Roperch, P.; Hervé, F.; Diraison, M.; Espinoza, M.; Arriagada, C.</p> <p>2014-12-01</p> <p>The Magallanes fold and thrust belt (FTB) presents a large-scale curvature from N-S oriented structures north of 52°S to nearly E-W in Tierra del Fuego Island. We present a paleomagnetic and anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) study from 85 sites sampled in Cretaceous to Miocene marine sediments. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> is lower than 0.0005 SI for 76 sites and mainly controlled by paramagnetic minerals. AMS results indicate that the sedimentary fabric is preserved in the undeformed areas of Tierra del Fuego and the more external thrust sheets units, where an incipient lineation due to layer parallel shortening is recorded. Prolate AMS ellipsoids, indicating a significant tectonic imprint in the AMS fabric, are observed in the internal units of the belt. AMS results show a good correlation between the orientation of the <span class="hlt">magnetic</span> lineation and the fold axes. However, in Península Brunswick, the AMS lineations are at ~20° counterclockwise to the strike of the fold axes. Pretectonic stable characteristic remanent <span class="hlt">magnetizations</span> (ChRM) were determined in seven sites. A counterclockwise rotation (21.2° ± 9.2°) is documented by ChRM data from four sites near the hinge of the belt in Península Brunswick and near Canal Whiteside while there is no evidence of rotation near the nearly E-W oriented Vicuña thrust within Tierra del Fuego. The curved shape of the Cenozoic Magallanes FTB is not related to vertical axis rotation, and thus, the Magallanes FTB can be considered as a primary arc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1299497','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1299497"><span>The <span class="hlt">susceptibility</span> of pure tubulin to high <span class="hlt">magnetic</span> fields: a <span class="hlt">magnetic</span> birefringence and x-ray fiber diffraction study.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bras, W; Diakun, G P; Díaz, J F; Maret, G; Kramer, H; Bordas, J; Medrano, F J</p> <p>1998-01-01</p> <p>The orientational behavior of microtubules assembled in strong <span class="hlt">magnetic</span> fields has been studied. It is shown that when microtubules are assembled in a <span class="hlt">magnetic</span> field, they align with their long axis parallel to the <span class="hlt">magnetic</span> field. The effect of several parameters known to affect the microtubule assembly are investigated with respect to their effect on the final degree of alignment. Aligned samples of hydrated microtubules suitable for low-resolution x-ray fiber diffraction experiments have been produced, and the results obtained from the fiber diffraction experiments have been compared with the <span class="hlt">magnetic</span> birefringence experiments. Comparisons with earlier fiber diffraction work and small-angle x-ray solution scattering experiments have been made. PMID:9512047</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3428333','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3428333"><span>Erythrocyte Enrichment in Hematopoietic Progenitor Cell Cultures Based on <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> of the Hemoglobin</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jin, Xiaoxia; Abbot, Stewart; Zhang, Xiaokui; Kang, Lin; Voskinarian-Berse, Vanessa; Zhao, Rui; Kameneva, Marina V.; Moore, Lee R.; Chalmers, Jeffrey J.; Zborowski, Maciej</p> <p>2012-01-01</p> <p>Using novel media formulations, it has been demonstrated that human placenta and umbilical cord blood-derived CD34+ cells can be expanded and differentiated into erythroid cells with high efficiency. However, obtaining mature and functional erythrocytes from the immature cell cultures with high purity and in an efficient manner remains a significant challenge. A distinguishing feature of a reticulocyte and maturing erythrocyte is the increasing concentration of hemoglobin and decreasing cell volume that results in increased cell magnetophoretic mobility (MM) when exposed to high <span class="hlt">magnetic</span> fields and gradients, under anoxic conditions. Taking advantage of these initial observations, we studied a noninvasive (label-free) <span class="hlt">magnetic</span> separation and analysis process to enrich and identify cultured functional erythrocytes. In addition to the <span class="hlt">magnetic</span> cell separation and cell motion analysis in the <span class="hlt">magnetic</span> field, the cell cultures were characterized for cell sedimentation rate, cell volume distributions using differential interference microscopy, immunophenotyping (glycophorin A), hemoglobin concentration and shear-induced deformability (elongation index, EI, by ektacytometry) to test for mature erythrocyte attributes. A commercial, packed column high-gradient <span class="hlt">magnetic</span> separator (HGMS) was used for <span class="hlt">magnetic</span> separation. The <span class="hlt">magnetically</span> enriched fraction comprised 80% of the maturing cells (predominantly reticulocytes) that showed near 70% overlap of EI with the reference cord blood-derived RBC and over 50% overlap with the adult donor RBCs. The results demonstrate feasibility of label-free <span class="hlt">magnetic</span> enrichment of erythrocyte fraction of CD34+ progenitor-derived cultures based on the presence of paramagnetic hemoglobin in the maturing erythrocytes. PMID:22952572</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22952572','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22952572"><span>Erythrocyte enrichment in hematopoietic progenitor cell cultures based on <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of the hemoglobin.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jin, Xiaoxia; Abbot, Stewart; Zhang, Xiaokui; Kang, Lin; Voskinarian-Berse, Vanessa; Zhao, Rui; Kameneva, Marina V; Moore, Lee R; Chalmers, Jeffrey J; Zborowski, Maciej</p> <p>2012-01-01</p> <p>Using novel media formulations, it has been demonstrated that human placenta and umbilical cord blood-derived CD34+ cells can be expanded and differentiated into erythroid cells with high efficiency. However, obtaining mature and functional erythrocytes from the immature cell cultures with high purity and in an efficient manner remains a significant challenge. A distinguishing feature of a reticulocyte and maturing erythrocyte is the increasing concentration of hemoglobin and decreasing cell volume that results in increased cell magnetophoretic mobility (MM) when exposed to high <span class="hlt">magnetic</span> fields and gradients, under anoxic conditions. Taking advantage of these initial observations, we studied a noninvasive (label-free) <span class="hlt">magnetic</span> separation and analysis process to enrich and identify cultured functional erythrocytes. In addition to the <span class="hlt">magnetic</span> cell separation and cell motion analysis in the <span class="hlt">magnetic</span> field, the cell cultures were characterized for cell sedimentation rate, cell volume distributions using differential interference microscopy, immunophenotyping (glycophorin A), hemoglobin concentration and shear-induced deformability (elongation index, EI, by ektacytometry) to test for mature erythrocyte attributes. A commercial, packed column high-gradient <span class="hlt">magnetic</span> separator (HGMS) was used for <span class="hlt">magnetic</span> separation. The <span class="hlt">magnetically</span> enriched fraction comprised 80% of the maturing cells (predominantly reticulocytes) that showed near 70% overlap of EI with the reference cord blood-derived RBC and over 50% overlap with the adult donor RBCs. The results demonstrate feasibility of label-free <span class="hlt">magnetic</span> enrichment of erythrocyte fraction of CD34+ progenitor-derived cultures based on the presence of paramagnetic hemoglobin in the maturing erythrocytes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GGG....17.2940I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GGG....17.2940I"><span>Improving the method of low-temperature anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (LT-AMS) measurements in air</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Issachar, R.; Levi, T.; Lyakhovsky, V.; Marco, S.; Weinberger, R.</p> <p>2016-07-01</p> <p>This study examines the limitations of the method of low-temperature anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (LT-AMS) measurements in air and presents technical improvements that significantly reduce the instrumental drift and measurement errors. We analyzed the temperature profile of porous chalk core after cooling in liquid nitrogen and found that the average temperature of the sample during the LT-AMS measurement in air is higher than 77K and close to 92K. This analysis indicates that the <span class="hlt">susceptibility</span> of the paramagnetic minerals are amplified by a factor ˜3.2 relative to that of room temperature AMS (RT-AMS). In addition, it was found that liquid nitrogen was absorbed in the samples during immersing and contributed diamagnetic component of ˜-9 × 10-6 SI to the total mean <span class="hlt">susceptibility</span>. We showed that silicone sheet placed around and at the bottom of the measuring coil is an effective thermal protection, preventing instrument drift by the cold sample. In this way, the measuring errors of LT-AMS reduced to the level of RT-AMS, allowing accurate comparison with standard AMS measurements. We examined the applicability of the LT-AMS measurements on chalk samples that consist <5% (weight) of paramagnetic minerals and showed that it helps to efficiently enhance the paramagnetic fabric. The present study offers a practical approach, which can be applied to various types of rocks to better delineate the paramagnetic phase using conventional equipment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4508405','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4508405"><span>Proton Nuclear <span class="hlt">Magnetic</span> Resonance Spectroscopy as a Technique for Gentamicin Drug <span class="hlt">Susceptibility</span> Studies with Escherichia coli ATCC 25922</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>García-Álvarez, Lara; Busto, Jesús H.; Avenoza, Alberto; Sáenz, Yolanda; Peregrina, Jesús Manuel</p> <p>2015-01-01</p> <p>Antimicrobial drug <span class="hlt">susceptibility</span> tests involving multiple time-consuming steps are still used as reference methods. Today, there is a need for the development of new automated instruments that can provide faster results and reduce operating time, reagent costs, and labor requirements. Nuclear <span class="hlt">magnetic</span> resonance (NMR) spectroscopy meets those requirements. The metabolism and antimicrobial <span class="hlt">susceptibility</span> of Escherichia coli ATCC 25922 in the presence of gentamicin have been analyzed using NMR and compared with a reference method. Direct incubation of the bacteria (with and without gentamicin) into the NMR tube has also been performed, and differences in the NMR spectra were obtained. The MIC, determined by the reference method found in this study, would correspond with the termination of the bacterial metabolism observed with NMR. Experiments carried out directly into the NMR tube enabled the development of antimicrobial drug <span class="hlt">susceptibility</span> tests to assess the effectiveness of the antibiotic. NMR is an objective and reproducible method for showing the effects of a drug on the subject bacterium and can emerge as an excellent tool for studying bacterial activity in the presence of different antibiotic concentrations. PMID:25972417</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007PhRvB..75r4536S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007PhRvB..75r4536S"><span>Successive superconducting transitions in Ta2S2C studied by electrical resistivity and nonlinear ac <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Suzuki, Masatsugu; Suzuki, Itsuko S.; Noji, Takashi; Koike, Yoji; Walter, Jürgen</p> <p>2007-05-01</p> <p>Ta2S2C compound undergoes superconducting transitions at Tcl=3.60±0.02K and Tcu=9.0±0.2K . The nature of successive superconducting transitions has been studied from electrical resistivity and linear and nonlinear ac <span class="hlt">magnetic</span> <span class="hlt">susceptibilities</span>. The resistivity ρ at H=0 shows a local maximum near Tcu , a kinklike behavior around Tcl , and reduces to zero at below T0=2.1K . The lnT dependence of ρ is observed at H=50kOe at low temperatures, which is due to a two-dimensional weak-localization effect. Below Tcu , a two-dimensional superconducting phase occurs in each TaC layer. The linear and nonlinear <span class="hlt">susceptibilities</span> χ1″ , χ3' , χ5' , and χ7' as well as the difference δχ (=χFC-χZFC) between the field-cooled (FC) and zero-field-cooled (ZFC) <span class="hlt">susceptibilities</span> start to appear below 6.0K , the onset temperature of irreversibility. A drastic growth of the in-plane superconducting coherence length below 6.0K gives rise to a three-dimensional superconducting phase below Tcl through interplanar Josephson couplings between adjacent TaC layers. The oscillatory behavior of χ3″ , χ5″ , and χ7″ below Tcl is related to the nonlinear behavior arising from the thermally activated flux flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMGP23A1038T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMGP23A1038T"><span>Preliminary Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> and Paleomagnetic Data from Mafic Dikes in the Chili Quadrangle, Rio Arriba County, New Mexico</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trujillo, R. V.; Petronis, M. S.; Lineline, J.</p> <p>2011-12-01</p> <p>Migration of magma at shallow levels of the crust is a fundamental process that has bearing on the construction of volcanoes, associated hazards in active volcanic terranes, and igneous mass redistribution in near surface environments. This study examines a suite of Miocene mafic dikes in the Española Basin, north-central NM. The problems addressed by this research involves: 1) collect paleomagnetic data from the dikes to discern components of vertical-axis rotation across structural blocks, between separate dikes, and along strike within individual dikes, and 2) obtain anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) data, thin section, and field observations, to infer magma flow within each dike and document any variation in magma flow patterns within the swarm. We plan to test the following hypotheses: 1) the mafic dikes experienced some degree of vertical axis rotation associated with rifting and/or intrusion of younger dikes 2) the magma flow pattern within the dikes reflects lateral emplacement with flow directed away from the magma ascent location. Low-field <span class="hlt">susceptibility</span> versus temperature experiments yield a spectrum of results reflecting thermomagnetic behavior typical of intermediate composition titanomagnetite while others exhibit a more complex behavior with the presence of two or more <span class="hlt">magnetic</span> phases. Curie point estimates range from ~ 100°C to 575°C indicating a range of moderate to low Ti- titanomagnetite compositions as well as some evidence of a Fe-sulfide phase, possibly pyrrhotite. AMS fabric data reveal a combination of both prolate and oblate <span class="hlt">susceptibility</span> ellipsoids. At several sites, the fabrics are oblate from the paired dike margins and reveal a unique magma flow direction. <span class="hlt">Susceptibility</span> values are high and consistent with a ferromagnetic phase providing encouraging evidence that the remanence is likely a primary thermoremanent <span class="hlt">magnetization</span> and geologically stable. Paleomagnetic analysis is underway and should help further constrain the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...11..092C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...11..092C"><span><span class="hlt">Generalised</span> structures for N=1 AdS backgrounds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Coimbra, André; Strickland-Constable, Charles</p> <p>2016-11-01</p> <p>We expand upon a claim made in a recent paper [arXiv:1411.5721] that generic minimally supersymmetric AdS backgrounds of warped flux compactifications of Type II and M theory can be understood as satisfying a straightforward weak integrability condition in the language of {E}_{d(d)}× {R}+ <span class="hlt">generalised</span> geometry. Namely, they are spaces admitting a <span class="hlt">generalised</span> G-structure set by the Killing spinor and with constant singlet <span class="hlt">generalised</span> intrinsic torsion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5230783','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5230783"><span>Simultaneous Quantitative MRI Mapping of T1, T2* and <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> with Multi-Echo MP2RAGE</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kober, Tobias; Möller, Harald E.; Schäfer, Andreas</p> <p>2017-01-01</p> <p>The knowledge of relaxation times is essential for understanding the biophysical mechanisms underlying contrast in <span class="hlt">magnetic</span> resonance imaging. Quantitative experiments, while offering major advantages in terms of reproducibility, may benefit from simultaneous acquisitions. In this work, we demonstrate the possibility of simultaneously recording relaxation-time and <span class="hlt">susceptibility</span> maps with a prototype Multi-Echo (ME) <span class="hlt">Magnetization</span>-Prepared 2 RApid Gradient Echoes (MP2RAGE) sequence. T1 maps can be obtained using the MP2RAGE sequence, which is relatively insensitive to inhomogeneities of the radio-frequency transmit field, B1+. As an extension, multiple gradient echoes can be acquired in each of the MP2RAGE readout blocks, which permits the calculation of T2* and <span class="hlt">susceptibility</span> maps. We used computer simulations to explore the effects of the parameters on the precision and accuracy of the mapping. In vivo parameter maps up to 0.6 mm nominal resolution were acquired at 7 T in 19 healthy volunteers. Voxel-by-voxel correlations and the test-retest reproducibility were used to assess the reliability of the results. When using optimized paramenters, T1 maps obtained with ME-MP2RAGE and standard MP2RAGE showed excellent agreement for the whole range of values found in brain tissues. Simultaneously obtained T2* and <span class="hlt">susceptibility</span> maps were of comparable quality as Fast Low-Angle SHot (FLASH) results. The acquisition times were more favorable for the ME-MP2RAGE (≈ 19 min) sequence as opposed to the sum of MP2RAGE (≈ 12 min) and FLASH (≈ 10 min) acquisitions. Without relevant sacrifice in accuracy, precision or flexibility, the multi-echo version may yield advantages in terms of reduced acquisition time and intrinsic co-registration, provided that an appropriate optimization of the acquisition parameters is performed. PMID:28081157</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26197427','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26197427"><span>An environmental <span class="hlt">generalised</span> Luenberger-Hicks-Moorsteen productivity indicator and an environmental <span class="hlt">generalised</span> Hicks-Moorsteen productivity index.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Abad, A</p> <p>2015-09-15</p> <p>The purpose of this paper is to introduce an environmental <span class="hlt">generalised</span> productivity indicator and its ratio-based counterpart. The innovative environmental <span class="hlt">generalised</span> total factor productivity measures inherit the basic structure of both Hicks-Moorsteen productivity index and Luenberger-Hicks-Moorsteen productivity indicator. This methodological contribution shows that these new environmental <span class="hlt">generalised</span> total factor productivity measures yield the earlier standard Hicks-Moorsteen index and Luenberger-Hicks-Moorsteen indicator, as well as environmental performance index, as special cases.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPCM...29jLT01C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPCM...29jLT01C"><span><span class="hlt">Magnetization</span> at the interface of Cr2O3 and paramagnets with large stoner <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Shi; Street, M.; Wang, Junlei; Wang, Jian; Zhang, Xiaozhe; Binek, Ch; Dowben, P. A.</p> <p>2017-03-01</p> <p>From the Cr 2p3/2 x-ray <span class="hlt">magnetic</span> circular dichroism signal, there is clear evidence of interface polarization with overlayers of both Pd and Pt on chromia (Cr2O3). The residual boundary polarization of chomia is stronger for a Pt overlayer than in the case of a Pd overlayer. The reduction of chromia boundary <span class="hlt">magnetization</span> with a paramagnetic metal overlayer, compared to the free surface, is interpreted as a response to the induced spin polarization in Pt and Pd. <span class="hlt">Magnetization</span> induced in a Pt overlayer, via proximity to the chromia boundary <span class="hlt">magnetization</span>, is evident in the polar magneto-optical Kerr measurements. These results are essential to explainations why Pt and Pd are excellent spacer layers for voltage controlled exchange bias, in the [Pd/Co] n /Pd/Cr2O3 and [Pt/Co] n /Pt/Cr2O3 perpendicular magneto-electric exchange bias systems. The findings pave the way to realize ultra-fast reversal of induced <span class="hlt">magnetization</span> in a free moment paramagnetic layer, with possible application in voltage-controlled <span class="hlt">magnetic</span> random access memory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5700433','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5700433"><span>Synthesis and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of M /SUB x/ V/sub 2/O/sub 3//sup +/y solid solutions (M = Ca, Sr, Ba)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Volkov, V.L.; Milova, G.D.; Perelyaev, V.A.</p> <p>1985-12-01</p> <p>The authors synthesize and study the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of solid solutions of alkaline-earth metal oxides in V/sub 2/O/sub 3/. As the initial substances ultrapure V/sub 2/O/sub 5/, CaCo/sub 3/, BaCO/sub 3/, and SrCO/sub 3/ and chemically pure metavanadates and orthovanadates of alkaline-earth metals were used. The x-ray analysis was carried out on a DRON-2.5 diffractometer with ionization detection of Cu Ka radiation. The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> was measured by the Faraday method. The authors establish the existence of solid solutions of composition MxV/sub 2/O/sub 3//sup +/y, determine their crystallographic parameters, and study the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>. The transition temperature of the specimens decreases as the radius of the M/sup 2 +/ ions and the unit-cell parameter c of the crystal decrease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNS52A..05K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNS52A..05K"><span>A Laboratory Study to Determine the Effect of Field Strength and <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> on the NMR Estimated Water Content in Unconsolidated Sediments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keating, K.; Grunewald, E. D.; Walsh, D. O.</p> <p>2015-12-01</p> <p>Geophysical nuclear <span class="hlt">magnetic</span> resonance (NMR) well logging data can provide direct information about subsurface water content. While NMR water content estimates are known to be accurate in low <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> materials, it has often been assumed that NMR measurements cannot be used in high <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> materials due to internal <span class="hlt">magnetic</span> field inhomogeneities that arise due to <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> contrasts in the material. In this study we compare the NMR estimated water content using laboratory measurements made at two low <span class="hlt">magnetic</span> field strengths (with Larmor frequencies of 275 kHz and 2 MHz) on both synthetic and natural unconsolidated sediments with a range of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> values. NMR measurements were collected on seven water-saturated materials with <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> values spanning three orders of magnitude (3.6x10-6 SI to 7.0 x10-3 SI). T2 relaxation time data was collected with echo times, tE, ranging from 200 to 3000 μs. The results show that for the materials with low <span class="hlt">magnetic</span> <span class="hlt">susceptibilities</span> (< 5x10-4 SI), the total water content was accurately estimated at both field strengths. For the materials with high <span class="hlt">magnetic</span> <span class="hlt">susceptibilities</span> (> 5x10-4 SI) the water content was more accurately estimated using the data collected at 275 kHz (> 80% detected at tE = 400 μs) than the data collected at 2 MHz (< 40% detected at tE = 400 μs). Furthermore, the 275 kHz data showed water content underestimation errors increased only slightly with increased tE, compared to substantial increases in errors for the 2 MHz data as tE was increased. This finding suggests that there is an advantage for collecting measurements at lower field strengths even for long tE. We explain the differences in the water content estimates at the two field strengths by considering the shape of the echoes and the coil and pulse bandwidths, and find excellent agreement with the range of collected NMR data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014RuMaS..69..957B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014RuMaS..69..957B"><span>Turbulence for the <span class="hlt">generalised</span> Burgers equation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boritchev, A. A.</p> <p>2014-12-01</p> <p>This survey reviews rigorous results obtained by A. Biryuk and the author on turbulence for the <span class="hlt">generalised</span> space-periodic Burgers equation \\displaystyle u_t+f'(u)u_x=ν uxx+η,\\qquad x \\in S^1={R}/{Z}, where f is smooth and strongly convex, and the constant 0<ν\\ll 1 corresponds to the viscosity coefficient. Both the unforced case ( η=0) and the case when η is a random force which is smooth with respect to x and irregular (kick or white noise) with respect to t are considered. In both cases sharp bounds of the form Cν-δ, δ≥slant 0, are obtained for the Sobolev norms of u averaged over time and over the ensemble, with the same value of δ for upper and lower bounds. These results yield sharp bounds for small-scale quantities characterising turbulence, confirming the physical predictions. Bibliography: 56 titles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JMMM..385...65A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JMMM..385...65A"><span>AC-<span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of Dy doped ZnO compounds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Akyol, Mustafa; Ekicibil, Ahmet; Kiymaç, Kerim</p> <p>2015-07-01</p> <p>Dy doped ZnO polycrystalline diluted <span class="hlt">magnetic</span> semiconductor compounds have been prepared by the so called solid state reaction method. We have studied the M-H and AC <span class="hlt">magnetic</span> properties of the compounds by using a PPMS magnetometer, and explored the phases and crystal structure by using a X-ray powder diffractometer. The XRD spectra of the compounds show that the substitution of Dy3+ for Zn2+ causes almost no change in the hexagonal wurtzite structure of ZnO, and the Dy3+ ions are successfully substituted into the Zn2+ site of the ZnO matrix. The <span class="hlt">magnetic</span> measurements, M-H and χ-T, for T in the range from 10 to 300 K, show a paramagnetic behavior, including indirect antiferromagnetic couplings between some Dy3+ <span class="hlt">magnetic</span> moments. Since the Curie-Weiss temperatures, θ, are all negative but decrease in magnitude with increasing Dy concentration. On the other hand, the calculated effective <span class="hlt">magnetic</span> moments, μeff, per Dy3+ ion slowly increase with increasing Dy concentration, but are all very close to the free ion value of μeff, ~11.0 μB. Therefore, the trends of the magnitudes of θs and μeff s indicate that the samples are not only paramagnetic but also have antiferromagnetic couplings due to the complex nature of the compounds. In addition, the thermal variation of average <span class="hlt">magnetic</span> moment, Peff(T), per Dy3+ ion have been calculated, and have been found to be gradually increasing with increasing temperature and Dy concentration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Scientific+AND+claims+AND+issue&id=EJ1054046','ERIC'); return false;" href="http://eric.ed.gov/?q=Scientific+AND+claims+AND+issue&id=EJ1054046"><span>Supporting Teachers to Attend to <span class="hlt">Generalisation</span> in Science Classroom Argumentation</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Shemwell, Jonathan T.; Gwarjanski, Kalee R.; Capps, Daniel K.; Avargil, Shirly; Meyer, Joanna L.</p> <p>2015-01-01</p> <p>In scientific arguments, claims must have meaning that extends beyond the immediate circumstances of an investigation. That is, claims must be <span class="hlt">generalised</span> in some way. Therefore, teachers facilitating classroom argumentation must be prepared to support students' efforts to construct or criticise <span class="hlt">generalised</span> claims. However, widely used…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11114062','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11114062"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> shift selected imaging (MESSI) and localized (1)H(2)O spectroscopy in living plant tissues.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhong, K; Li, X; Shachar-Hill, Y; Picart, F; Wishnia, A; Springer, C S</p> <p>2000-11-01</p> <p>Maize root segments permeated with aqueous solutions of the paramagnetic agents GdDTPA(2-) or DyDTPA-BMA display two well-resolved NMR peaks corresponding to the signals from intracellular and extracellular (1)H(2)O, which arise from well-understood bulk <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> effects. This allows each component to be studied separately. Images obtained at each frequency with MESSI editing, and single- and multiple-voxel ('spectroscopic imaging') localized spectra, clearly indicate that the agents permeate into the interstitial spaces, and into the longitudinal (xylem/phloem) channels in the stele (core) of the root, confirming earlier assessments. We believe these are the first images of a multicellular tissue acquired in vivo exclusively from the intracellular water proton resonance. This method can be further exploited to study water transport in similar systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005NIMPB.239..281L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005NIMPB.239..281L"><span>The effects of 137Cs and 60Co γ radiation on the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of BSCCO textured thin rods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leyva, A.; Cruz, C. M.; Mora, M.; Shtejer, K.; Diez, J. C.; Angurel, L. A.; Piñera, I.; Abreu, Y.</p> <p>2005-09-01</p> <p>Bi 2Sr 2CaCu 2O x superconducting thin rods textured by the laser floating zone melting method were irradiated with 1250 and 662 keV γ rays. The behavior of some of its superconducting properties with the exposure dose was studied by the measurement of dynamic <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>. It was observed that, for different dose levels according to the energy of the incident radiation, the rods preserve their superconducting intragrain properties, evidencing the high resistance of the material to the γ radiation damage. In all the cases it was verified that, with increasing exposure dose, the onset temperature of the superconducting transition increases. The possible mechanisms that should take place are analyzed in the text. The χac measurements also show the increasing behavior of the superconducting volume fraction in the sample with the exposure dose.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23266939','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23266939"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> measurements to detect coal fly ash from the Kingston Tennessee spill in Watts Bar Reservoir.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cowan, Ellen A; Seramur, Keith C; Hageman, Steven J</p> <p>2013-03-01</p> <p>An estimated 229,000 m(3) of coal fly ash remains in the river system after dredging to clean-up the 2008 Tennessee Valley Authority (TVA) spill in Kingston, Tennessee. The ash is heterogeneous with clear, orange and black spheres and non-spherical amorphous particles. Combustion produces iron oxides that allow low field <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (χ(LF)) and percent frequency dependent <span class="hlt">susceptibility</span> (χ(FD)%) to be used to discriminate between coal fly ash and sediments native to the watershed. Riverbed samples with χ(LF) greater than 3.0 × 10(-6) m(3)/kg, have greater than 15% ash measured by optical point counting. χ(LF) is positively correlated with total ash, allowing ash detection in riverbed sediments and at depth in cores. The ratio of ash sphere composition is altered by river transport introducing variability in χ(LF). Measurement of χ(LF) is inexpensive, non-destructive, and a reliable analytical tool for monitoring the fate of coal ash in this fluvial environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990040275','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990040275"><span>Exploiting the Temperature/Concentration Dependence of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> to Control Convection in Fundamental Studies of Solidification Phenomena</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Evans, J. W.; Xu, Dong; Jones, W. Kinzy, Jr.; Szofran, Frank R.</p> <p>1999-01-01</p> <p>The objective of this new research project is to demonstrate by experiment, supplemented by mathematical modeling and physical property measurement, that the effects of buoyancy driven convection can be largely eliminated in ground-based experiments, and further reduced in flight, by applying a new technique. That technique exploits the dependence of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> on composition or temperature. It is emphasized at the outset that the phenomenon to be exploited is fundamentally and practically different from the <span class="hlt">magnetic</span> damping of convection in conducting liquids that has been the subject of much prior research. The concept suggesting this research is that all materials, even non-conductors, when placed in a <span class="hlt">magnetic</span> field gradient, experience a force. Of particular interest here are paramagnetic and diamagnetic materials, classes which embrace the "model alloys", such as succinonitrile-acetone, that have been used by others investigating the fundamentals of solidification. Such alloys will exhibit a dependence of <span class="hlt">susceptibility</span> on composition. The consequence is that, with a properly oriented field (gradient) a force will arise that can be made to be equal to, but opposite, the buoyancy force arising from concentration (or temperature) gradients. In this way convection can be stilled. The role of convection in determining the microstructure, and thereby properties, of materials is well known. Elimination of that convection has both scientific and technological consequences. Our knowledge of diffusive phenomena in solidification, phenomena normally hidden by the dominance of convection, is enhanced if we can study solidification of quiescent liquids. Furthermore, the microstructure, microchemistry and properties of materials (thereby practical value) are affected by the convection occurring during their solidification. Hitherto the method of choice for elimination of convection has been experimentation in microgravity. However, even in low Earth orbit</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005E%26PSL.238..110V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005E%26PSL.238..110V"><span>The use of field dependence of AC <span class="hlt">susceptibility</span> for the interpretation of <span class="hlt">magnetic</span> mineralogy and <span class="hlt">magnetic</span> fabrics in the HSDP-2 basalts, Hawaii [rapid communication</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vahle, Carsten; Kontny, Agnes</p> <p>2005-09-01</p> <p> anisotropy exhibit differences of the field dependence parameter if measured parallel to kmax or kmin axis. Therefore, in addition to compositional effects and the temperature dependence, the <span class="hlt">magnetic</span> fabric has to be considered for the interpretation of field dependent <span class="hlt">susceptibility</span> measurements. The influence of intrinsic (Ti-content, magnetocrystalline anisotropy), and extrinsic (shape and alignment of grains) factors for the interpretation of the degree of anisotropy has to be kept in mind when interpreting AMS data in terms of strain rates experienced by moving lava during emplacement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EP%26S...61..173C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EP%26S...61..173C"><span>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> analysis of the Cantera Ignimbrite, San Luis Potosi, México: flow source recognition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caballero-Miranda, C. I.; Torres-Hernández, J. R.; Alva-Valdivia, L. M.</p> <p>2009-01-01</p> <p>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) was selected as the key technique to find the source of the widespread Cantera Ignimbrite and to seek its possible relationship with the San Luis Potosí Caldera. Eighteen sites (372 specimens from 155 cores) from the Oligocene Cantera Ignimbrite were sampled. AMS was measured on a KLY2 Kappabridge. AMS data were processed with Anisoft 3 software using Jelinek statistics as well as `SpheriStat' principal components and density distribution. Mean <span class="hlt">susceptibilities</span> range from 290 to 5026 × 10-6 SI (average = 2526 × 10-6 SI). The anisotropy degree ( P j) ranges from 1.005 to 1.055, with only one site displaying a value of 1.134 ( P j average = 1.031). AMS ellipsoid shapes are mostly oblate, with the T-factor ranging from 0.843 to 0.144 ( T average = 0.529), although one site is mainly prolate ( T = -0.005), and three additional sites have an important proportion of prolate specimens. <span class="hlt">Magnetic</span> fabrics of most sites shows k3 axes around nearly circular distributions and k 1- k 2 axes around elongated-girdle distributions defining sub-horizontal foliation planes; exceptions to this are related to sites with a significant percentage of prolate specimens. Flow directions inferred from AMS analysis indicate several ignimbrite sources located along selected NW-SE linear features (faults and fractures such as El Potosino Fault) as well as along the rim of the caldera structure. The geometry of volcanic outcrops, the NW-SE faulting-fracture system, as well as the AMS results suggest that this is a caldera structure resembling the trapdoor-type (Lipman, 1997).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP31A1096H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP31A1096H"><span>Implications of Late Pliocene-Pleistocene Humidity Fluctuations in the Qaidam Paleolake (NE Tibetan Plateau) Deduced from <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Herb, C.; Appel, E.; Koutsodendris, A.; Zhang, W.; Pross, J.; Fang, X.</p> <p>2014-12-01</p> <p>The Qaidam Basin (NE Tibetan Plateau) contains a near-continuous, up to 12 km thick sequence of Cenozoic strata that offers a unique opportunity for studying long-term climate change. We investigate the 940-m-long drill core SG-1 from the western Qaidam Basin, which is characterized by a long-term transition from a semi-deep freshwater lake to nearly complete exsiccation of the water body, detected by several studies including geochemical and lithological observations. Based on magnetostratigraphy and optically stimulated luminescence dating, and refined by orbital tuning, the SG-1 core spans the interval from 2.69 to 0.1 Ma. Moisture availability in the western Qaidam Basin deduced from the pollen ratio Artemisia/Chenopodiaceae (A/C), suggests desert to steppe vegetation along core SG-1 as a long-term feature. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (χ) is well suited for the high-resolution investigation of paleohumidity. The meaning of χ as a paleohydrology proxy is shown by comparing χ to other <span class="hlt">magnetic</span> proxies for checking its relation to <span class="hlt">magnetic</span> grain sizes and <span class="hlt">magnetic</span> mineralogy as well as to pollen results. χ variations are analyzed to obtain regional information on the factors leading to the drying process of the Qaidam paleolake as well as potential driving factors for humidity fluctuations (e.g., insolation). An important topic that needs further investigation is the influence of monsoon in the Qaidam Basin. While the southern part of the Tibetan Plateau is directly affected by monsoon precipitation through the topographic barrier, its influence in the past is questionable in the hyper-arid Qaidam Basin. We check a potential coupling to the monsoon system in the western Qaidam Basin by comparing our χ record to reconstructions of the Asian monsoon system from other archives as well as searching evidence from orbital cyclicities found in the χ time series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SSCom.153...60P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SSCom.153...60P"><span>Low temperature <span class="hlt">magnetic</span> ground state in bulk Co0.3Zn0.7Fe2O4 spinel ferrite system: Neutron diffraction, <span class="hlt">magnetization</span> and ac-<span class="hlt">susceptibility</span> studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parmar, Harshida; Acharya, Prashant; Upadhyay, R. V.; Siruguri, V.; Rayaprol, Sudhindra</p> <p>2013-01-01</p> <p>The system under study is a bulk Co0.3Zn0.7Fe2O4 ferrite, synthesized by wet chemical route technique and having <span class="hlt">magnetic</span> in-homogeneity at the microscopic scale, due to the concentration of <span class="hlt">magnetic</span> ion at a tetrahedral site below the site percolation threshold for the ferrimagnetic ordering. To unravel the <span class="hlt">magnetic</span> ground state of this system, low temperature neutron diffraction, <span class="hlt">magnetization</span> and ac-<span class="hlt">susceptibility</span> measurements were carried out. In the temperature-dependent neutron diffraction analysis, a diffused scattering signal appears at the low Q region below (1 1 1) <span class="hlt">magnetic</span> Bragg peak at all temperature, indicating the presence of a finite <span class="hlt">magnetic</span> cluster with infinite <span class="hlt">magnetic</span> network. The diffused scattering signal intensity decreases with increases in <span class="hlt">magnetic</span> field at T=10 K. The ac-<span class="hlt">susceptibility</span> measurement exhibits three peak behavior in χ' and χ″ indicating the presence of finite <span class="hlt">magnetic</span> clusters and cluster-cluster interaction in the system. The absence of <span class="hlt">magnetic</span> (2 0 0) peak in neutron diffraction at 2 K and bifurcation of zero field and field cooled <span class="hlt">magnetization</span> indicate the phase transition from uniaxial random ferromagnetic (URF) phase to semi spin glass or canted random ferromagnetic (CRF) phase in the system with temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2008/1352/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2008/1352/"><span>Mineralogic Causes of Variations in <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> of Late Pleistocene and Holocene Sediment from Great Salt Lake, Utah</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Reynolds, Richard L.; Rosenbaum, Joseph G.; Thompson, Robert S.</p> <p>2008-01-01</p> <p>We describe here results of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS) measurements and <span class="hlt">magnetic</span> mineralogy of sediments sampled in three cores from the south basin of Great Salt Lake. The cores were obtained in 1996 with a Kullenburg-type piston corer at sites in close proximity: core 96-4 at 41 deg 01.00' N, 112 deg 28.00' W and cores 96-5 and 96-6 at 41 deg 00.09' N, 112 deg 23.05' W. Cores 96-5 (2.16 m long) and -6 combine to make a composite 11.31-m sediment record. Sediments in core 96-4 (5.54 m long) correspond to the approximate depth interval of 3.9-9.6 m in the composite core of 96-5 and -6 based on similarities in the MS records as described below. The central goal of the research was to provide a sediment record of paleoenvironmental change in the northeastern Basin and Range Province over the past 40,000 years. Specific targets included a sedimentologic record of lake-level change combined with a pollen record of climatic change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997JMagR.127...17S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997JMagR.127...17S"><span>Using Bulk <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> to Resolve Internal and External Signals in the NMR Spectra of Plant Tissues</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shachar-Hill, Yair; Befroy, Douglas E.; Pfeffer, Philip E.; Ratcliffe, R. George</p> <p>1997-07-01</p> <p>Internal and external NMR signals from a variety of plant cells and plant tissues can be resolved by changing the bulk <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (BMS) of the perfusing medium with [Gd (EDTA)]-or Dy(DTPA-BMA). This separation is observed in samples consisting of cylindrical cells oriented along theB0field, and is consistent with established theoretical predictions about BMS effects. Evidence is presented that the shifted signals represent material outside the tissue as well as some contribution from intercellular spaces and cell walls, while intracellular signals are unshifted. The paramagnetic complexes used to separate the signals are shown to be nontoxic and to have no effect on a number of transport processes. The method has been applied to roots, shoots, and giant algal cells, facilitating the interpretation of thein vivospectra from a range of biologically important <span class="hlt">magnetic</span> isotopes. The potential of the method for studies of transport is illustrated with experiments showing: (i)14N/15N isotopic exchange of nitrate in roots; (ii) the influx of HDO into root and shoot segments; and (iii) the use of saturation transfer to follow water movement into and out of plant cells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JMagR.160...47D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JMagR.160...47D"><span>The elimination of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> artifacts in the micro-image of liquid-solid interfaces: internal gradient modulation by the CPMG RF train</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duh, Andrej; Mohorič, Aleš; Stepišnik, Janez; Serša, Igor</p> <p>2003-01-01</p> <p>Distortions of <span class="hlt">magnetic</span> resonance images near solid-liquid interface appear as the result of the restriction to spin self-diffusion in the proximity of impermeable boundary as well as of a <span class="hlt">susceptibility</span> difference. The spectral analysis of spin echo enables to resolve, in a simple way, how various RF-gradient pulse sequences reduce the effect of the internal <span class="hlt">magnetic</span> field induced by the <span class="hlt">susceptibility</span> difference at interfaces. The 1D diffusion-weighted imaging of water in the narrow notch tested efficiency of some sequence. The notch was milled in a piece of Plexiglas. The method can be used to distinguish the <span class="hlt">susceptibility</span> effect from the effects of applied gradients when investigating the transport of fluid through a porous structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhyS...73..519M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhyS...73..519M"><span>Persistent current and low-field <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> in one channel mesoscopic loops and Möbius strips</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maiti, Santanu K.</p> <p>2006-06-01</p> <p>I study persistent current and low-field <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of one-dimensional normal metal mesoscopic rings and Möbius strips threaded by slowly varying <span class="hlt">magnetic</span> flux phi. In strictly one-channel perfect rings, current shows saw-tooth-like variation with phi for the cases where the rings contain odd and even number of electrons Ne respectively. But in disordered rings, current shows a continuous variation with phi. In these systems current has only phi0 flux-quantum periodicity. Now in Möbius strips, the motion of the electrons in the transverse direction has an important factor on persistent current and also on low-field <span class="hlt">magnetic</span> response. If the electrons are unable to hop in the transverse direction then an electron encircles the system twice before returning to its initial position and current obtains phi0/2 flux-quantum periodicity unlike phi0 flux-quantum periodicity in strictly one-channel rings or multi-channel cylinders. The sign of the low-field currents in one-channel mesoscopic rings can be predicted exactly, even in the presence of impurity in these systems. For perfect rings current has only diamagnetic behaviour in the limit of zero field irrespective of the total number of electrons Ne. On the other hand, in dirty rings, current shows paramagnetic and diamagnetic signs respectively for the rings with even and odd Ne. In Möbius strips for zero hopping strength of the electrons in the transverse direction we get exactly the same behaviour as in strictly one-channel rings, but for nonzero transverse hopping strength the sign of the low-field currents cannot be predicted since it strongly depends on Ne and the specific realization of disorder configuration of the systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JAP...105gB518S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JAP...105gB518S"><span>ac <span class="hlt">susceptibility</span> studies of <span class="hlt">magnetic</span> relaxation in nanoparticles of Ni dispersed in silica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, V.; Seehra, M. S.; Bonevich, J.</p> <p>2009-04-01</p> <p>Temperature dependence of ac <span class="hlt">susceptibilities</span> χ' and χ″ are reported using frequencies fm=0.1, 1, 99, 499, and 997 Hz for nanoparticles of Ni dispersed in silica (Ni/SiO2:15/85) with the mean sizes D =3.8, 11.7, 15, and 21 nm (σ ≃0.2 nm), as determined by transmission electron microscopy. The blocking temperatures TB, as determined by peaks in χ″ versus T data, are fit to the Vogel-Fulcher law based on the following equation: TB=To+Ta/ln(fo/fm). Using the attempt frequency fo=1.82×1010 Hz, Ta (K)=310 (21), 954(17), 1334(14), and 1405(47) are determined for D =3.8, 11.7, 15, and 21 nm, respectively, along with To (representing the interparticle interaction)=0, 0, 6.6(0.7), and 12.5(2.5) K respectively. The magnitudes of Ta=KaV/k yield the anisotropy constant Ka increasing with decreasing D (or volume V) due to contributions from surface anisotropy. The validity of the theoretical result χ″=C∂(χ'T)/∂T with C ≃π/[2 ln(fo/2πfm)] is checked and the calculated values of fo are consistent with experimental value of fo=1.82×1010 Hz.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1123583','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1123583"><span>Partial Spin Ordering and Complex <span class="hlt">Magnetic</span> Structure in BaYFeO4: A Neutron Diffraction and High Temperature <span class="hlt">Susceptibility</span> Study</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Thompson, Corey; Greedan, John; Garlea, Vasile O; Flacau, Roxana; Tan, Malinda; Derakhshan, Shahab</p> <p>2014-01-01</p> <p>The novel iron-based compound, BaYFeO4, crystallizes in the Pnma space group with two distinct Fe3+ sites, that are alternately corner-shared [FeO5]7 square pyramids and [FeO6]9 octahedra, forming into [Fe4O18]24 rings, which propagate as columns along the b-axis. A recent report shows two discernible antiferromagnetic (AFM) transitions at 36 and 48 K in the <span class="hlt">susceptibility</span>, yet heat capacity measurements reveal no <span class="hlt">magnetic</span> phase transitions at these temperatures. An upturn in the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements up to 400 K suggests the presence of shortrange <span class="hlt">magnetic</span> behavior at higher temperatures. In this Article, variable-temperature neutron powder diffraction and hightemperature <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements were performed to clarify the <span class="hlt">magnetic</span> behavior. Neutron powder diffraction confirmed that the two <span class="hlt">magnetic</span> transitions observed at 36 and 48 K are due to long-range <span class="hlt">magnetic</span> order. Below 48 K, the <span class="hlt">magnetic</span> structure was determined as a spin-density wave (SDW) with a propagation vector, k = (0, 0, 1/3), and the moments along the b-axis, whereas the structure becomes an incommensurate cycloid [k = (0, 0, 0.35)] below 36 K with the moments within the bc-plane. However, for both cases the ordered moments on Fe3+ are only of the order 3.0 B, smaller than the expected values near 4.5 B, indicating that significant components of the Fe moments remain paramagnetic to the lowest temperature studied, 6 K. Moreover, new high-temperature <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements revealed a peak maximum at 550 K indicative of short-range spin correlations. It is postulated that most of the <span class="hlt">magnetic</span> entropy is thus removed at high temperatures which could explain the absence of heat capacity anomalies at the long-range ordering temperatures. Published spin dimer calculations, which appear to suggest a k = (0, 0, 0) <span class="hlt">magnetic</span> structure, and allow for neither low dimensionality nor geometric frustration, are inadequate to explain the observed complex <span class="hlt">magnetic</span></p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24405325','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24405325"><span>Partial spin ordering and complex <span class="hlt">magnetic</span> structure in BaYFeO4: a neutron diffraction and high temperature <span class="hlt">susceptibility</span> study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thompson, Corey M; Greedan, John E; Garlea, V Ovidiu; Flacau, Roxana; Tan, Malinda; Nguyen, Phuong-Hieu T; Wrobel, Friederike; Derakhshan, Shahab</p> <p>2014-01-21</p> <p>The novel iron-based compound, BaYFeO4, crystallizes in the Pnma space group with two distinct Fe(3+) sites, that are alternately corner-shared [FeO5](7-) square pyramids and [FeO6](9-) octahedra, forming into [Fe4O18](24-) rings, which propagate as columns along the b-axis. A recent report shows two discernible antiferromagnetic (AFM) transitions at 36 and 48 K in the <span class="hlt">susceptibility</span>, yet heat capacity measurements reveal no <span class="hlt">magnetic</span> phase transitions at these temperatures. An upturn in the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements up to 400 K suggests the presence of short-range <span class="hlt">magnetic</span> behavior at higher temperatures. In this Article, variable-temperature neutron powder diffraction and high-temperature <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements were performed to clarify the <span class="hlt">magnetic</span> behavior. Neutron powder diffraction confirmed that the two <span class="hlt">magnetic</span> transitions observed at 36 and 48 K are due to long-range <span class="hlt">magnetic</span> order. Below 48 K, the <span class="hlt">magnetic</span> structure was determined as a spin-density wave (SDW) with a propagation vector, k = (0, 0, (1)/3), and the moments along the b-axis, whereas the structure becomes an incommensurate cycloid [k = (0, 0, ∼0.35)] below 36 K with the moments within the bc-plane. However, for both cases the ordered moments on Fe(3+) are only of the order ∼3.0 μB, smaller than the expected values near 4.5 μB, indicating that significant components of the Fe moments remain paramagnetic to the lowest temperature studied, 6 K. Moreover, new high-temperature <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements revealed a peak maximum at ∼550 K indicative of short-range spin correlations. It is postulated that most of the <span class="hlt">magnetic</span> entropy is thus removed at high temperatures which could explain the absence of heat capacity anomalies at the long-range ordering temperatures. Published spin dimer calculations, which appear to suggest a k = (0, 0, 0) <span class="hlt">magnetic</span> structure, and allow for neither low dimensionality nor geometric frustration, are inadequate to explain the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/8779282','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/8779282"><span>[The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of the melanin in the eyes of representatives of different vertebrate classes].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zagal'skaia, E O</p> <p>1995-01-01</p> <p>The magnetoperceptivity (Chi) and element composition of eye pigment epitelium (EPE) melanin in vertebrate animals were measured. The minimal values of EPE Chi were found in winter-sleeping and anabiotic animals (Ursus arctos, Rana temporaria). The magnetoperception was high in migrating animals (Oncorhynchus keta, 0. gorbuscha, Anas crecca) and in wild gray rats as well, EPE magnetoperceptivity in albino rats wasn't practicaly established. In the majority of cases the quantity of magnetoperceptivity correlates with per-cent content of iron. The evident correlation between melanin <span class="hlt">magnet</span> properties and the life strategy of the investigated animals allows to propose the participance of eye pigment epithelium in orientation and navigation of the animals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRB..120..662M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRB..120..662M"><span>Magma flow pattern in dykes of the Azores revealed by anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moreira, M. A.; Geoffroy, L.; Pozzi, J. P.</p> <p>2015-02-01</p> <p>The localization of magma melting areas at the lithosphere bottom in extensional volcanic domains is poorly understood. Large polygenetic volcanoes of long duration and their associated magma chambers suggest that melting at depth may be focused at specific points within the mantle. To validate the hypothesis that the magma feeding a mafic crust, comes from permanent localized crustal reservoirs, it is necessary to map the fossilized magma flow within the crustal planar intrusions. Using the AMS, we obtain magmatic flow vectors from 34 alkaline basaltic dykes from São Jorge, São Miguel and Santa Maria islands in the Azores Archipelago, a hot-spot related triple junction. The dykes contain titanomagnetite showing a wide spectrum of solid solution ranging from Ti-rich to Ti-poor compositions with vestiges of maghemitization. Most of the dykes exhibit a normal <span class="hlt">magnetic</span> fabric. The orientation of the <span class="hlt">magnetic</span> lineation k1 axis is more variable than that of the k3 axis, which is generally well grouped. The dykes of São Jorge and São Miguel show a predominance of subhorizontal magmatic flows. In Santa Maria the deduced flow pattern is less systematic changing from subhorizontal in the southern part of the island to oblique in north. These results suggest that the ascent of magma beneath the islands of Azores is predominantly over localized melting sources and then collected within shallow magma chambers. According to this concept, dykes in the upper levels of the crust propagate laterally away from these magma chambers thus feeding the lava flows observed at the surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSMGP31B..02C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSMGP31B..02C"><span>Analysis of the <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> Anisotropy of the Cantera Ignimbrite, San Luis Potosé­ Volcanic field, Mexico</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caballero, C.; Torres-Hernandez, J.; Alva-Valdivia, L. M.</p> <p>2007-05-01</p> <p>Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> (AMS) results from a group of 17 - 18 sites (286 - 312 specimens) from the Cantera Ignimbrite - of Oligocene age and part of the San Luis Potosí Volcanic Filed (SLPVF), México - are presented and analysed in order to help to determine the source and flow directions. In each site a flow direction is inferred based on AMS results. As the Cantera Ignimbrite is generally dipping, AMS was structural corrected. So two sets of geographical and paleo-geographical (structural corrected) inferred-flow directions were obtained. Both sets are analysed trying to define if the source of the ignimbrite is related to a calderic (concentric structure) or to the NW-SE faulting and jointing. Geographical AMS results mostly give SW flow directions, the southernmost sites give to SSE. Meanwhile structural corrected results give a wider range of flow directions, a group of them to NW and another northerly group mostly to NE. AMS was measured in a KLY2 appliance, Jelinek and other statistics and density distributions were performed, giving all very similar results in each site. Mean <span class="hlt">susceptibilities</span> range from 147 to 27200 x10-6 SI (average = 5713 x10-6 SI). Anisotropy degree (Pj) range from 1.011 to 1.055 with two sites of 1.134-1.254 (Pj average = 1.046). Shape is mostly oblate ranging the T-factor from 0.843 to 0.409 and only one site mainly prolate: T of -0.277 (T average = 0.550).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999JVGR...91..167O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999JVGR...91..167O"><span>Correlation of deposits and vent locations of the proximal Campanian Ignimbrite deposits, Campi Flegrei, Italy, based on natural remanent <span class="hlt">magnetization</span> and anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> characteristics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ort, Michael H.; Rosi, Mauro; Anderson, Charles D.</p> <p>1999-08-01</p> <p>Correlation of the distal deposits of the Campanian Ignimbrite with their proximal equivalents in the Campi Flegrei caldera is complicated by a lack of medial exposures, complex and limited proximal stratigraphic sections, and large lateral facies changes. Paleomagnetic data from 10 sites in and near the Campi Flegrei yield natural remanent <span class="hlt">magnetizations</span> (NRM) that are statistically indistinguishable from the distal Campanian Ignimbrite. In addition, their virtual geomagnetic pole (VGP) yields a possible correlation with Lac du Bouchet, France, secular variation data that indicate an age of approximately 32,850 14C years. The secular variation curve at this age was only briefly at this VGP, and did not return to it for >10,000 years, so the paleomagnetic correlation of proximal and distal deposits is unique and robust. The date is consistent with 14C dates from the Campanian Ignimbrite, but younger than 39Ar/ 40Ar dates for the same rocks. This suggests that a better correction factor for cosmic flux for this time period is needed to calibrate older 14C dates. Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) data show that the proximal deposits have an oblate (disk-shaped), poorly lineated <span class="hlt">magnetic</span> fabric. The distal deposits are much better lineated. The difference may be due to chaotic depositional currents in the proximal areas, in which particles were not well aligned. With greater distance of travel, and loss of energy, particles within the flow became aligned and developed stronger AMS lineations. Early eruptions of the Piperno Tuff were from a central vent north of Pozzuoli, whereas later tuffs that underlie the Breccia Museo may have been emplaced by flows associated with ring vents located on the northern and southern caldera margins.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25648156','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25648156"><span><span class="hlt">Generalisation</span> of fear and avoidance along a semantic continuum.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Boyle, Sean; Roche, Bryan; Dymond, Simon; Hermans, Dirk</p> <p>2016-01-01</p> <p>Directly conditioned fear and avoidance readily <span class="hlt">generalises</span> to dissimilar but conceptually related stimuli. Here, for the first time, we examined the conceptual/semantic <span class="hlt">generalisation</span> of both fear and avoidance using real words (synonyms). Participants were first exposed to a differential fear conditioning procedure in which one word (e.g., "broth"; CS+) was followed with brief electric shock [unconditioned stimulus (US)] and another was not (e.g., "assist"; CS-). Next, an instrumental conditioning phase taught avoidance in the presence the CS+ but not the CS-. During <span class="hlt">generalisation</span> testing, synonyms of the CS+ (e.g., "soup"; GCS+) and CS- (e.g., "help"; GCS-) were presented in the absence of shock. Conditioned fear and avoidance, measured via skin conductance responses, behavioural avoidance and US expectancy ratings, <span class="hlt">generalised</span> to the semantically related, but not to the semantically unrelated, synonyms. Findings have implications for how natural language categories and concepts mediate the expansion of fear and avoidance repertoires in clinical contexts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...08..074C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...08..074C"><span>Exceptional <span class="hlt">generalised</span> geometry for massive IIA and consistent reductions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cassani, Davide; de Felice, Oscar; Petrini, Michela; Strickland-Constable, Charles; Waldram, Daniel</p> <p>2016-08-01</p> <p>We develop an exceptional <span class="hlt">generalised</span> geometry formalism for massive type IIA supergravity. In particular, we construct a deformation of the <span class="hlt">generalised</span> Lie derivative, which generates the type IIA gauge transformations as modified by the Romans mass. We apply this new framework to consistent Kaluza-Klein reductions preserving maximal supersymmetry. We find a <span class="hlt">generalised</span> parallelisation of the exceptional tangent bundle on S 6, and from this reproduce the consistent truncation ansatz and embedding tensor leading to dyonically gauged ISO(7) supergravity in four dimensions. We also discuss closely related hyperboloid reductions, yielding a dyonic ISO( p, 7 - p) gauging. Finally, while for vanishing Romans mass we find a <span class="hlt">generalised</span> parallelisation on S d , d = 4 , 3 , 2, leading to a maximally supersymmetric reduction with gauge group SO( d + 1) (or larger), we provide evidence that an analogous reduction does not exist in the massive theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...11..063C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...11..063C"><span>Supersymmetric backgrounds, the Killing superalgebra, and <span class="hlt">generalised</span> special holonomy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Coimbra, André; Strickland-Constable, Charles</p> <p>2016-11-01</p> <p>We prove that, for M theory or type II, generic Minkowski flux backgrounds preserving N supersymmetries in dimensions D ≥ 4 correspond precisely to integrable <span class="hlt">generalised</span> {G}_{N} structures, where {G}_{N} is the <span class="hlt">generalised</span> structure group defined by the Killing spinors. In other words, they are the analogues of special holonomy manifolds in {E}_{d(d)}× {R}+ <span class="hlt">generalised</span> geometry. In establishing this result, we introduce the Kosmann-Dorfman bracket, a <span class="hlt">generalisation</span> of Kosmann's Lie derivative of spinors. This allows us to write down the internal sector of the Killing superalgebra, which takes a rather simple form and whose closure is the key step in proving the main result. In addition, we find that the eleven-dimensional Killing superalgebra of these backgrounds is necessarily the supertranslational part of the N -extended super-Poincaré algebra.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JLTP..182...13L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JLTP..182...13L"><span>A 2-Level Condensate with Tunable and Sharp <span class="hlt">Susceptibility</span> Against the <span class="hlt">Magnetic</span> Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Z. B.; Yao, D. X.; He, Y. Z.; Bao, C. G.</p> <p>2016-01-01</p> <p>A 2-level condensate of spin-1 Na atoms under a <span class="hlt">magnetic</span> field B with its spin modes decoupled from its spatial modes is studied. This system can emerge at very low temperature by putting an atom with its spin down into a fully polarized condensate with all N-1 spins up, similar to embedding an impurity into a well-organized system. The most distinguished feature of this 2-level system is that it is inert to B in general, but extremely sensitive to B in a specific domain D-o-S around B_0 at which the energy gap between the two levels arrives at a minimum. Population oscillations are found and the underlying regularity is clarified and described by simple formulae. Therefore, the inherent dynamic parameters of the condensate can be known via the measurement of the population. The experimental condition that such a system can exist has been evaluated. Furthermore, there is a characteristic constant γ =0.278466 common to various 2-level systems. This constant provides a common upper bound γ kBT for the internal energy U of all these systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012Tectp.532....1G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012Tectp.532....1G"><span><span class="hlt">Generalised</span> receiver functions and seismic interferometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Galetti, Erica; Curtis, Andrew</p> <p>2012-04-01</p> <p>Classical seismological receiver functions are correlational or deconvolutional combinations of vertical and horizontal component seismometer recordings of earthquake waves that focus information on near-receiver subsurface Earth structure and properties. We show that seismic interferometry can be thought of as a <span class="hlt">generalisation</span> of receiver functions analysis to cases where recordings at pairs of receivers are considered simultaneously, and where either the same or different component recordings are combined. Further, seismic interferometry uses any of deconvolution, convolution and cross-correlation, and energy from either impulsive or random noise sources. We show both how receiver functions can logically be extended to a new, convolutional form, and that the now little-used correlational form of receiver functions contains more intuitive information than previously realised. Seismic interferometry has provided other extraordinary extensions to seismologists' arsenal. Passive noise recordings can be converted into seismograms from virtual (imagined) earthquakes that in turn can be used to image the real Earth. Active sources (e.g., earthquakes or man-made sources) can be redatumed into new, virtual sources elsewhere, or can be converted into virtual sensors (seismometers) that record seismograms from other real earthquakes, man-made sources or noise sources that occur either in the future or in the past. And the ability to construct virtual sources and sensors at desired times and locations (rather than having to wait for earthquake sources that occur at uncontrollable locations) promises more repeatable monitoring of changes in Earth subsurface properties over time. Indeed, so-called coda wave interferometry offers unprecedented accuracy in detecting such changes. Finally, existing theoretical extensions to other regimes such as electromagnetic, electrokinetic and diffusive energy propagation may lead to future revolutions in other domains of science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMGP12A..04S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMGP12A..04S"><span>Paired <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> Cyclostratigraphy and Revised Magnetostratigraphy with Late Cretaceous Euler Pole from Forbes Formation, Sand Creek, Sacramento Valley, California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Slotznick, S. P.; Raub, T.; Mitchell, R. N.; Ward, P. D.; Kirschvink, J. L.</p> <p>2012-12-01</p> <p>Magnetostratigraphy in Upper Cretaceous rocks of Sacramento Valley has successfully complemented biostratigraphy for correlating between circum-Pacific basins. Most paleomagnetic measurements were done pre-1990 using alternating field demagnetization only, due to oxidation accompanying thermal demagnetization. We present paleomagnetic data collected via thermal demagnetization in a flowing nitrogen atmosphere from 223 cores collected over a 130m of section of Forbes Formation in Sand Creek, CA spanning upper Dobbins Shale, Forbes Unit 2 and lower Unit 3. These results uniformly indicate Reversed Chron 33R, contra previously published magnetostratigraphy of the area (Ward et al. 1983, Verosub et al. 1989). Additionally, these paleomagnetic results yield a tightly-constrained paleolatitude for Forbes Formation of 31±3°, which varies significantly from previous APWP models ca. 83 Ma (Besse and Courtillot, 2002) suggesting an unaccounted-for deficiency in reconstructions of North America at this time. This discrepancy might indicate an inaccurate cratonic reference pole, underestimated intrabatholithic or distributed plate boundary deformation, and/or true polar wander. As opposed to other units yielding anomalous late Cretaceous paleolatitudes from outboard terranes, Forbes Formation in Sacramento Valley laps unambiguously onto the North American continent. A 25m AW34 core was collected using a Winkie drillrig near the top of Dobbins Shale Mbr. Paleomagnetic measurements on subsamples from the Winkie core, unaffected by surface weathering, combine with the surficial dataset, and we propose a new set of Euler pole solutions potentially quantifying Basin and Range extension and late Cretaceous intra-Sierran shear. Through <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements of the Winkie core, we were able to resolve orbital cycles which, paired with rock <span class="hlt">magnetic</span> measurements, constrain basin subsidence and sedimentation rate off the Sierran arc at its age of termination. Re</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..94v4420T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..94v4420T"><span>Model analysis of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of Sr2IrO4 : A two-dimensional Jeff=1/2 Heisenberg system with competing interlayer couplings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takayama, Tomohiro; Matsumoto, Akiyo; Jackeli, George; Takagi, Hidenori</p> <p>2016-12-01</p> <p>We report the analysis of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> χ (T ) of Sr2IrO4 single crystal in the paramagnetic phase. We formulate the theoretical <span class="hlt">susceptibility</span> based on isotropic Heisenberg antiferromagnetism incorporating the Dzyaloshinsky-Moriya interaction exactly, and include the interlayer couplings in a mean-field approximation. χ (T ) above TN was found to be well described by the model, indicating the predominant Heisenberg exchange consistent with the microscopic theory. The analysis points to a competition of nearest and next-nearest-neighbor interlayer couplings, which results in the up-up-down-down configuration of the in-plane canting moments identified by the diffraction experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMGP33A1115S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMGP33A1115S"><span>Time as An Important Soil-Forming Factor Influencing Modern and Ancient <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> Enhancement Along the Delaware River Valley, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stinchcomb, G. E.; Peppe, D. J.; Driese, S. G.</p> <p>2011-12-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> is an increasingly popular low-cost method for rapidly assessing paleoclimate and paleoenvironmental impact on buried soils. The goal of this study is to determine the primary influence(s) on soil <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> along floodplain, terrace and upland soils in the middle Delaware River Valley, USA, using environmental <span class="hlt">magnetic</span>, pedologic, and stratigraphic techniques. Two-hundred thirty samples were collected from age-constrained sandy, quartz-rich, floodplain, terrace, and upland soils (Entisols, Inceptisols). A Kruskal-Wallis (K-W) and post-hoc Tukey-Kramer (T-K) (α=0.05) multiple comparisons analysis on 176 mass-specific low-field <span class="hlt">susceptibility</span> (Xlf) assays show that A and B horizons are <span class="hlt">magnetically</span> enhanced compared to C and E horizons (p<0.0001). Results of descriptive soil micromorphology show that A and B horizons contain anywhere from 10-50% more amorphous organic matter and clay films along pores than do C and E horizons. Enhanced Xlf values also correlate positively (R^2=0.63) with the soil molecular weathering ratio of Alumina/Bases, suggesting that increased weathering likely results in the formation of pedogenic <span class="hlt">magnetic</span> minerals and enhanced <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> signal. Additional K-W and T-K testing show that Xlf results, when grouped by floodplain-terrace designation (i.e., chronofunction) are significantly different (p<0.0001). The older T3 terrace and upland Xlf values (0.34±0.14 10^-6 m^3 kg^-1) are greater than the younger T2 terrace (0.18±0.06 10^-6 m^3 kg^-1) values, which are greater than modern floodplain (0.09±0.01 10^-6 m^3 kg^-1) Xlf values. These data suggest that longer intervals of soil formation enhance the Χlf value. This hypothesis is further supported when 159 Xlf values are plotted vs. age for the entire Holocene. A locally-weighted regression smoothing curve (LOESS) shows two distinct intervals of <span class="hlt">magnetic</span> enhancement during previously established dry intervals, the early and late</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4779003','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4779003"><span>Predicting Mortality in Patients With “Malignant” Middle Cerebral Artery Infarction Using <span class="hlt">Susceptibility</span>-Weighted <span class="hlt">Magnetic</span> Resonance Imaging</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chao, Shu-Ping; Chen, Chia-Yuen; Tsai, Fong Y.; Chan, Wing P.; Chen, Chin-I</p> <p>2016-01-01</p> <p>Abstract To evaluate malignant middle cerebral artery (MCA) infarction (defined as space-occupying edema in more than 50% to 75% of the MCA territory) on <span class="hlt">magnetic</span> resonance imaging (MRI) with <span class="hlt">susceptibility</span>-weighted imaging (SWI) sequence and assess the usefulness of SWI findings, diffusion-weighted imaging (DWI) findings, and apparent diffusion coefficient (ADC) as predictors of clinical outcome. Data from 16 patients with large MCA infarction previously admitted to our institution between December 2009 and October 2012 were retrospectively collected and analyzed. Within 7 days after stroke onset, 1 neurologist and 1 neuroradiologist estimated the area of infarction on DWI/ADC and extent of prominent vessel sign (PVS) on SWI images using the Stroke Program Early MR Score (SPEMRS). The PVS on SWI was defined as a local prominence of hypointense vessels with either increased vessel number or diameter in the target area, when compared with the number or diameter of the contralateral MCA territory vessels. Six patients died and 10 survived. Although the DWI/ADC-SPEMRS and clinical profiles were similar between the nonsurvivor and survivor groups, SWI-SPEMRS was significantly lower in the nonsurvivor group (P < 0.001). The area of deoxygenation on SWI in patients with malignant MCA infarction can predict mortality. Lower SWI-SPEMRS is a potentially better predictor of poor outcome than lower DWI-SPEMRS. A larger prospective study is needed to clarify the role of SWI as a therapeutic guide in malignant MCA. PMID:26937906</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70020723','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70020723"><span><span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> and Mineral Zonations Controlled by Provenance in Loess along the Illinois and Central Mississippi River Valleys</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Grimley, D.A.; Follmer, L.R.; McKay, E.D.</p> <p>1998-01-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (MS) patterns have proven useful for regional stratigraphic correlations of zones within thick, oxidized Peoria and Roxana Silts along the Illinois and Central Mississippi River valleys for more than 350 km. Variations in MS of C horizon loess are controlled by silt-sized magnetite content and are interpreted to reflect changes in sediment provenance due to fluctuations of the Superior and Lake Michigan glacier lobes and the diversion of the Mississippi River to its present course. Grain size distributions and scanning electron microscopic observations indicate that stratigraphic changes in MS are not significantly influenced by eolian sorting or diagenetic dissolution, respectively. Three compositional zones (lower, middle, and upper) are delineated within Peoria Silt which usually can be traced in the field by MS, the occurrence of clay beds, interstadial soils, and/or subtle color changes. These zones can be correlated with, but are generally of more practical use than, previously studied dolomite zones (McKay, 1977) or clay mineral zones (Frye et al., 1968). However, mineralogical analyses can help to substantiate zone boundaries when in question. MS and compositional zones may indirectly record a climatic signal, primarily through the effect that global cooling has had on ice lobe fluctuations in the Upper Mississippi drainage basin. ?? 1998 University of Washington.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhLA..381.1261Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhLA..381.1261Y"><span>Electronic miniband structure, heat capacity and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of monolayer and bilayer silicene in TI, VSPM and BI regimes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yarmohammadi, Mohsen</p> <p>2017-04-01</p> <p>In the current work, we theoretically study the electronic band structure (EBS), electronic heat capacity (EHC) and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS) of three structures including monolayer, AA-stacked and AB-stacked bilayer silicene based on the Kane-Mele Hamiltonian model and Green's function method. The particular attention of this study is paid to the effect of external electric field on the aforementioned physical properties. By variation of the electric field, three phases are found: Topological insulator (TI), valley-spin polarized metal (VSPM) and band insulator (BI). Marvellously, its electronic minibands show that the spin-up contribution of charge carriers with lowest energy bands behaves like relativistic Dirac fermions with linear (parabolic) energy dispersions in monolayer (bilayer) case near the Dirac points. An insightful analysis shows that the maximum and minimum value of EHC peak appear for (AA) AB-stacked bilayer and monolayer silicene in TI (BI) regime while in MS curves appear for (AB) AA-stacked bilayer and monolayer lattices in TI (BI) regime, respectively. Moreover, we have observed a phase transition from antiferromagnetic to ferromagnetic and paramagnetic in the monolayer and bilayer structures in the VSPM regime based on the MS findings, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5379544','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5379544"><span>Amide proton transfer <span class="hlt">magnetic</span> resonance imaging in detecting intracranial hemorrhage at different stages: a comparative study with <span class="hlt">susceptibility</span> weighted imaging</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ma, Xiaoyue; Bai, Yan; Lin, Yusong; Hong, Xiaohua; Liu, Taiyuan; Ma, Lun; Haacke, E Mark; Zhou, Jinyuan; Wang, Jian; Wang, Meiyun</p> <p>2017-01-01</p> <p>Amide proton transfer (APT) imaging is a noninvasive molecular <span class="hlt">magnetic</span> resonance imaging (MRI) technique based on the chemical exchange-dependent saturation transfer mechanism. The purpose of this study was to investigate the diagnostic performance of APT MRI in detecting intracranial hemorrhage (ICH) at hyperacute, acute and subacute stages by comparing with <span class="hlt">susceptibility</span> weighted imaging (SWI). APT MRI and SWI were performed on 33 included patients with ICH by using a 3-T MRI unit. A two-sided Mann-Whitney U test was used to detect differences in APT-weighted (APTw) and SWI signal intensities of ICH at hyperacute, acute and subacute stages. Receiver operating characteristic analysis was used to assess the diagnostic utilities of APT MRI and SWI. Our results showed that APT MRI could detect ICH at hyperacute, acute and subacute stages. Therefore, APTw signal intensity may serve as a reliable, noninvasive imaging biomarker for detecting ICH at hyperacute, acute and subacute stages. Moreover, APT MRI could provide additional information for the ICH compared with SWI. PMID:28374764</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JPCM...25w6003G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JPCM...25w6003G"><span>A cluster-glass <span class="hlt">magnetic</span> state in R5Pd2 (R = Ho, Tb) compounds evidenced by AC-<span class="hlt">susceptibility</span> and neutron scattering measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gubkin, A. F.; Sherstobitova, E. A.; Terentyev, P. B.; Hoser, A.; Baranov, N. V.</p> <p>2013-06-01</p> <p>AC- and DC-<span class="hlt">susceptibility</span>, high-field <span class="hlt">magnetization</span> and neutron diffraction measurements have been performed in order to study the <span class="hlt">magnetic</span> state of R5Pd2 (R = Ho, Tb) compounds. The results show that both compounds undergo cluster-glass freezing upon cooling below Tf. According to the neutron diffraction a long-range <span class="hlt">magnetic</span> order is absent down to 2 K and <span class="hlt">magnetic</span> clusters with short-range incommensurate antiferromagnetic correlations exist not only below Tf but also in a wide temperature range above the freezing temperature (at least up to 2Tf). A complex cluster-glass <span class="hlt">magnetic</span> state existing in Ho5Pd2 and Tb5Pd2 down to low temperatures results in rather complicated <span class="hlt">magnetization</span> behavior in DC and AC <span class="hlt">magnetic</span> fields. Such an unusual <span class="hlt">magnetic</span> state in compounds with a high rare-earth concentration may be associated with the layered type of their crystal structure and with substantial atomic disorder, which results in frustrations in the <span class="hlt">magnetic</span> subsystem.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/1016689','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/1016689"><span>Investigation of the electronic term scheme of deoxygenated human haemoglobin by a least squares fit procedure using simultaneously <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and Mössbauer data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bade, D; Parak, F</p> <p>1976-12-22</p> <p>The calculation of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> from a published term scheme for the ferrous iron in deoxygenated human haemoglobin is discussed and a procedure for the simultaneous least squares fit of <span class="hlt">susceptibility</span> and Mössbauer data is presented. The application of this procedure to the appropriate measurements on human haemoglobin leads to a rearrangement of the low lying electronic levels of the iron. The term schemes received as results of two different sets of <span class="hlt">susceptibility</span> data used in combination with one set of Mössbauer data overlap with their error bars. The obtained level scheme of the Fe is correlated with the distance of the iron atom from the haem plane and the distance Fe-HIS F8, and some biological implications of these correlations are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AIPC.1617..156Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AIPC.1617..156Z"><span>Effect of mechanical milling on particle size, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and dielectric of synthetic toner colorant magnetite extracted from Indonesian iron sand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zulaikah, S.; Mufti, N.; Fuad, A.; Dwi, L. D.</p> <p>2014-09-01</p> <p>As a colorant and additive substance for toner, magnetite (Fe3O4) has become main mineral that can produce electrical charge on printing process. In this research, we reports the effect of mechanical milling time to <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, morphology and dielectric properties of synthetic toner The standard of the grain size of toner including of magnetite dissolved, are ranged from 2 to 10 micron or less, depending on the kind of toner. The results of this research show that the average of particle size decreases from 15μm to 5 μm by milling time between 6 hour to 9 hour and almost constant up to 12 hour. The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of the sample decreases as decreasing particle size, while the dielectric constant increases as decreasing particle size.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.4655H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.4655H"><span>A record of Quaternary humidity fluctuations on the NE Tibetan Plateau based on <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> variations in lacustrine sediments of the Qaidam Basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Herb, Christian; Koutsodendris, Andreas; Zhang, Weilin; Appel, Erwin; Pross, Jörg; Fang, Xiaomin</p> <p>2013-04-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (?) and other <span class="hlt">magnetic</span> proxies play an important role in paleoclimatic studies as they hold the potential for high-resolution records of past environmental change. Nevertheless, it is necessary to understand the cause of the variation in <span class="hlt">magnetic</span> proxies by comparing them to more direct climate proxies such as pollen or stable isotopes. In this study we have compiled a high-resolution <span class="hlt">magnetic</span> proxy dataset of the ca. 940-m-long core SG-1, which was drilled in the lacustrine sediments of the western Qaidam Basin on the northeastern Tibetan Plateau. Our record spans the entire Quaternary (~2.8 to 0.1 Ma). The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> record is compared to the Artemisia/Chenopodiaceae (A/C) ratio, which is used to discriminate between dry and more humid phases in the Qaidam Basin, based on (i) 41 samples spanning the Middle Pleistocene Transition (MPT; ~1 Ma BP) and (ii) additional 40 samples selected from intervals of minimum and maximum ? values throughout the core. For the drill core SG-1, we observe a high correlation of the A/C ratio with ? results: minima of ? correspond to maxima of the A/C ratio (representing more humid phases) and vice versa. Additionally, spectral analysis of the ? record shows the emergence of the 100-ka Milankovitch cycle after the MPT. This testifies to the fact that cyclic variation of ? represents a response to global climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70026545','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70026545"><span>Using <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> to facilitate more rapid, reproducible and precise delineation of hydric soils in the midwestern USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Grimley, D.A.; Arruda, N.K.; Bramstedt, M.W.</p> <p>2004-01-01</p> <p>Standard field indicators, currently used for hydric soil delineations [USDA-NRCS, 1998. Field indicators of hydric soils in the United States, Version 4.0. In: G.W. Hurt et al. (Ed.), United States Department of Agriculture-NRCS, Fort Worth, TX], are useful, but in some cases, they can be subjective, difficult to recognize, or time consuming to assess. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (MS) measurements, acquired rapidly in the field with a portable meter, have great potential to help soil scientists delineate and map areas of hydric soils more precisely and objectively. At five sites in Illinois (from 5 to 15 ha in area) with contrasting soil types and glacial histories, the MS values of surface soils were measured along transects, and afterwards mapped and contoured. The MS values were found to be consistently higher in well-drained soils and lower in hydric soils, reflecting anaerobic deterioration of both detrital magnetite and soil-formed ferrimagnetics. At each site, volumetric MS values were statistically compared to field indicators to determine a critical MS value for hydric soil delineation. Such critical values range between 22??10-5 and 33??10-5 SI in silty loessal or alluvial soils in Illinois, but are as high as 61??10-5 SI at a site with fine sandy soil. A higher magnetite content and slower dissolution rate in sandy soils may explain the difference. Among sites with silty parent material, the lowest critical value (22??10-5 SI) occurs in soil with low pH (4.5-5.5) since acidic conditions are less favorable to ferrimagnetic mineral neoformation and enhance magnetite dissolution. Because of their sensitivity to parent material properties and soil pH, critical MS values must be determined on a site specific basis. The MS of studied soil samples (0-5 cm depth) is mainly controlled by neoformed ultrafine ferrimagnetics and detrital magnetite concentrations, with a minor contribution from anthropogenic fly ash. Neoformed ferrimagnetics are present in all samples</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26186443','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26186443"><span>Time-Transgressive Nature of the <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> Record across the Chinese Loess Plateau at the Pleistocene/Holocene Transition.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dong, Yajie; Wu, Naiqin; Li, Fengjiang; Huang, Linpei; Wen, Wenwen</p> <p>2015-01-01</p> <p>The loess stratigraphic boundary at the Pleistocene/Holocene transition defined by the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS) has previously been assumed to be synchronous with the Marine Isotope Stage (MIS) 2/1 boundary, and approximately time-synchronous at different sections across the Chinese Loess Plateau (CLP). However, although this assumption has been used as a basis for proxy-age model of Chinese loess deposits, it has rarely been tested by using absolute dating methods. In this study, we applied a single-aliquot regenerative-dose (SAR) protocol to the 45-63 μm quartz grain-size fraction to derive luminescence ages for the last glacial and Holocene sections of three loess sections on a transect from southeast to northwest across the CLP. Based on the 33 closely spaced optically stimulated luminescence (OSL) samples from the three sections, OSL chronologies were established using a polynomial curve fit at each section. Based on the OSL chronology, the timing of the Pleistocene/Holocene boundary, as defined by rapid changes in MS values, is dated at ~10.5 ka, 8.5 ka and 7.5 ka in the Yaoxian section, Jingchuan and Huanxian sections respectively. These results are clearly inconsistent with the MIS 2/1 boundary age of 12.05 ka, and therefore we conclude that the automatic correlation of the Pleistocene/Holocene transition, as inferred from the MS record, with the MIS 2/1 boundary is incorrect. The results clearly demonstrate that the marked changes in MS along the southeast to northwest transect are time-transgressive among the different sites, with the timing of significant paleosol development as indicated by the MS record being delayed by 3-4 ka in the northwest compared to the southeast. Our results suggest that this asynchronous paleosol development during the last deglacial was caused by the delayed arrival of the summer monsoon in the northwest CLP compared to the southeast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GGG....16.4029M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GGG....16.4029M"><span>Identifying cryptotephra units using correlated rapid, nondestructive methods: VSWIR spectroscopy, X-ray fluorescence, and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McCanta, Molly C.; Hatfield, Robert G.; Thomson, Bradley J.; Hook, Simon J.; Fisher, Elizabeth</p> <p>2015-12-01</p> <p>Understanding the frequency, magnitude, and nature of explosive volcanic eruptions is essential for hazard planning and risk mitigation. Terrestrial stratigraphic tephra records can be patchy and incomplete due to subsequent erosion and burial processes. In contrast, the marine sedimentary record commonly preserves a more complete historical record of volcanic activity as individual events are archived within continually accumulating background sediments. While larger tephra layers are often identifiable by changes in sediment color and/or texture, smaller fallout layers may also be present that are not visible to the naked eye. These cryptotephra are commonly more difficult to identify and often require time-consuming and destructive point counting, petrography, and microscopy work. Here we present several rapid, nondestructive, and quantitative core scanning methodologies (<span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, visible to shortwave infrared spectroscopy, and XRF core scanning) which, when combined, can be used to identify the presence of increased volcaniclastic components (interpreted to be cryptotephra) in the sedimentary record. We develop a new spectral parameter (BDI1000VIS) that exploits the absorption of the 1 µm near-infrared band in tephra. Using predetermined mixtures, BDI1000VIS can accurately identify tephra layers in concentrations >15-20%. When applied to the upper ˜270 kyr record of IODP core U1396C from the Caribbean Sea, and verified by traditional point counting, 29 potential cryptotephra layers were identified as originating from eruptions of the Lesser Antilles Volcanic Arc. Application of these methods in future coring endeavors can be used to minimize the need for physical disaggregation of valuable drill core material and allow for near-real-time recognition of tephra units, both visible and cryptotephra. This article was corrected on 23 DEC 2015. See the end of the full text for details.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.V13B2854F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.V13B2854F"><span>Influence of anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) on paleomagnetic sampling in volcanic glasses: a case study on rheomorphic ignimbrites of the Yellowstone hotspot-track, southern Idaho</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Finn, D.; Coe, R. S.; Murphy, J.; Bodiford, S.; Kelly, H.; Foster, S.; Spinardi, F.; Reichow, M. K.; Knott, T.; Branney, M. J.</p> <p>2012-12-01</p> <p>Large-scale explosive volcanism, associated with the Yellowstone hotspot, occurred in the central Snake River Plain between 12.5-8 Ma. It is characterized by unusually high-temperature, intensely welded, rheomorphic rhyolitic ignimbrites, typical of what is now known as 'Snake River (SR)-type volcanism'. Individual eruption volumes likely exceed 450 km3 but are poorly known due to the difficulty of correlating units between widely spaced (50-200 km) exposures along the north and south of the plain, when some occurred too close-spaced in time for radiometric resolution. Our goal is to use a combination of paleomagnetic, petrographic, chemical and field characterization to establish robust correlations, allowing us to develop a regional stratigraphy, and constrain ignimbrite eruption volumes and frequencies. This presentation focuses on how to sample rheomorphic, SR-type ignimbrites for paleomagnetic studies given the potential effects of hot, rheomorphic deformation. Individual SR-type ignimbrite cooling-units have an upper and lower glassy margins (vitrophyre) enclosing a lithoidal (microcrystalline) zone. We have sampled dozens of ignimbrites in detail and have observed that the lithoidal interiors are preferable to the glassy margins for paleomagnetic studies. We hypothesize that the glassy margins retain an anisotropic fabric related to emplacement compaction and/or shearing that affects their ability to accurately record the <span class="hlt">magnetic</span> field during cooling. In the lithoidal interiors this anisotropic fabric was overprinted by continued grain growth and/or alteration and, therefore, may accurately record the paleomagnetic field. Paleomagnetic samples from vitrophyres generally have a higher anisotropy in <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> than lithoidal samples. The remanent <span class="hlt">magnetic</span> directions recorded in samples with high anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> are often deflected away from the site mean and closer to the plane of easy <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>. Since the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21449026','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21449026"><span>Quantification of both the presence, and oxidation state, of Mn in Bacillus atrophaeus spores and its imparting of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> to the spores.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sun, Jianxin; Zborowski, Maciej; Chalmers, Jeffrey J</p> <p>2011-05-01</p> <p>Bacillus atrophaeus spores were previously reported to have significant <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> in a <span class="hlt">magnetic</span> field due to the presence of Mn. However, relatively little is known about the total amount and distribution of the oxidation state of Mn associated with this specific strain's spores. Using the instrument, cell tracking velocimetry (CTV) both <span class="hlt">magnetically</span> induced velocity and settling velocity was quantitatively measured. Visual observations, and calculated diameter using previously reported densities, indicate that the spores are present in the form of clusters of approximately 3-6 µm. Treatment of these clusters with EDTA or pH of 2.0 or below resulted in not only the disruption of the spore clusters, but also a significant decrease in <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, in some cases by almost two orders of magnitude. Since the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of Mn varies significantly between the three typically reported valance states of Mn, Mn(II), Mn(III), and Mn(IV); X-Ray Photoelectron Spectroscopy, XPS, was used to determined the valance states of Mn in the spores. This XPS analysis, which penetrates up to 10 nm into the spore, returned the following fractions: 0.41, 0.38, and 0.21 for the valance states: Mn(II), Mn(III), and Mn(IV), respectively. The total mass of Mn associated with each spore cluster was determined by ICP-MS. A second, completely independent estimate of Mn mass associated with each spore cluster was made, by mathematically solving for the amount of Mn per spore cluster using the experimentally measured magnetophoretic mobility and the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of each of the three valence states from the XPS analysis. IPC-MS returned a value of 3.28 × 10(-11) g of Mn per spore cluster while the calculated estimation from mobility and XPS analysis retuned a value of 1.16 × 10(-11) g, which given the complexity of the two techniques, is a reasonable agreement. Finally, a discussion of potential applications of the <span class="hlt">magnetic</span> properties</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AtmEn..39.2201G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AtmEn..39.2201G"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> of dust-loaded leaves as a proxy of traffic-related heavy metal pollution in Kathmandu city, Nepal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gautam, Pitambar; Blaha, Ulrich; Appel, Erwin</p> <p></p> <p>Dust-loaded tree leaves from Kathmandu have been analyzed for <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> ( χ) and heavy metal (HM) contents. For 221 samples of leaves of cypress (mainly Cupressus corneyana), silky oak ( Grevillea robusta) and bottlebrush ( Callistemon lanceolatus), χ has a range of (0.01-54)×10 -8 m 3 kg -1 with a median of about 10.0×10 -8 m 3 kg -1. Trees situated close to the busy road intersections, near the main bus station and sectors of roads with steep slope yield elevated <span class="hlt">susceptibility</span>. Chemical analysis of 20 samples of varying <span class="hlt">susceptibility</span> by atomic absorption spectrometry yields the following maximum HM contents: Fe (1.3 wt%), Mn (281.9 ppm), Zn (195.2 ppm), Cu (41.5 ppm), Pb (38.4 ppm), Ni (8.1 ppm), Cr (6.4 ppm), Co (4.1 ppm) and Cd (1.2 ppm). The logarithmic <span class="hlt">susceptibility</span> on dry mass basis ( χ) shows significant linear relationship with HM contents: Pearson's correlation coefficient r>0.8 with Zn, Fe, Cr; r>0.7 with Mn, Cu; r>0.6 with Pb, Ni. <span class="hlt">Magnetic</span> phases are of soft (magnetite/maghemite) and hard (hematite) coercivities. Microscopy of <span class="hlt">magnetic</span> extracts reveals spherules (mostly of 2-20 μm diameter) originated from vehicle exhausts through the combustion process as well as crystalline grains of lithogenic origin. The dust accumulation in leaves took place mainly after monsoon (beginning of October 2001) till the sampling period (first half of February 2002). Despite the dependence of <span class="hlt">susceptibility</span> and HM contents on a variety of spatial and temporal factors (amount of particulate matter (PM), efficiency of deposition/removal of PM by wind, precipitation, birds etc.), a significant correlation of <span class="hlt">susceptibility</span> to HM implies that the former serves as an effective proxy of metallic pollution. Hence, <span class="hlt">susceptibility</span>-based bio-monitoring technique is recommended as an economic and rapid tool for assessment of environmental pollution in urban areas like Kathmandu.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJTP..tmp...64H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJTP..tmp...64H"><span>Thermodynamics of a Charged Particle in a Noncommutative Plane in a Background <span class="hlt">Magnetic</span> Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Halder, Aslam; Gangopadhyay, Sunandan</p> <p>2017-03-01</p> <p>Landau system in noncommutative space has been considered. To take into account the issue of gauge invariance in noncommutative space, we incorporate the Seiberg-Witten map in our analysis. <span class="hlt">Generalised</span> Bopp-shift transformation is then used to map the noncommutative system to its commutative equivalent system. In particular we have computed the partition function of the system and from this we obtained the <span class="hlt">susceptibility</span> of the Landau system and found that the result gets modified by the spatial noncommutative parameter θ. We also investigate the de Hass-van Alphen effect in noncommutative space and observe that the oscillation of the <span class="hlt">magnetization</span> and the <span class="hlt">susceptibility</span> gets noncommutative corrections. Interestingly, the <span class="hlt">susceptibility</span> in the noncommutative scenario is non-zero in the range of the <span class="hlt">magnetic</span> field greater than the threshold value which is in contrast to its commutative counterpart. The results obtained are valid upto all orders in the noncommutative parameter θ.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21785185','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21785185"><span>Determination of the <span class="hlt">magnetic</span> ground state in the martensite phase of Ni-Mn-Z (Z = In, Sn and Sb) off-stoichiometric Heusler alloys by nonlinear AC <span class="hlt">susceptibility</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Umetsu, R Y; Fujita, A; Ito, W; Kanomata, T; Kainuma, R</p> <p>2011-08-17</p> <p>DC and AC <span class="hlt">magnetic</span> measurements were carried out to clarify the difference in the <span class="hlt">magnetic</span> ground state depending on the kinds of Z element used in the martensite phase in Ni-Mn-Z (Z = In, Sn and Sb) off-stoichiometric Heusler alloys. <span class="hlt">Magnetic</span> field cooling effects were observed in the DC thermomagnetization curves in the low temperature regions, and a frequency dependence on AC <span class="hlt">susceptibility</span> was also observed in both real and imaginary parts of the <span class="hlt">susceptibility</span>. Negative divergence was clearly observed in nonlinear AC <span class="hlt">susceptibility</span> only for the Ni(50)Mn(40)Sb(10) alloy, suggesting that the <span class="hlt">magnetic</span> feature of its ground state is the spin-glass state. The <span class="hlt">magnetic</span> ground state of the martensite phase in these alloys would relate to the <span class="hlt">magnetic</span> configuration of the Mn atoms in the ferromagnetic austenite phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JPhCS.285a2042P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JPhCS.285a2042P"><span><span class="hlt">Generalising</span> the logistic map through the q-product</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pessoa, R. W. S.; Borges, E. P.</p> <p>2011-03-01</p> <p>We investigate a <span class="hlt">generalisation</span> of the logistic map as xn+1 = 1 - axn otimesqmap xn (-1 <= xn <= 1, 0 < a <= 2) where otimesq stands for a <span class="hlt">generalisation</span> of the ordinary product, known as q-product [Borges, E.P. Physica A 340, 95 (2004)]. The usual product, and consequently the usual logistic map, is recovered in the limit q → 1, The tent map is also a particular case for qmap → ∞. The <span class="hlt">generalisation</span> of this (and others) algebraic operator has been widely used within nonextensive statistical mechanics context (see C. Tsallis, Introduction to Nonextensive Statistical Mechanics, Springer, NY, 2009). We focus the analysis for qmap > 1 at the edge of chaos, particularly at the first critical point ac, that depends on the value of qmap. Bifurcation diagrams, sensitivity to initial conditions, fractal dimension and rate of entropy growth are evaluated at ac(qmap), and connections with nonextensive statistical mechanics are explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70027289','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70027289"><span>Flow path of the 1993 Hokkaido-Nansei-oki earthquake seismoturbidite, suthern margin of the Japan sea north basin, inferred from anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Abdeldayem, A.L.; Ikehara, K.; Yamazaki, T.</p> <p>2004-01-01</p> <p>A <span class="hlt">magnetic</span> fabric analysis has been carried out on standard cube samples from one gravity and three multiple cores extracted from the Shiribeshi trough and Okushiri basin in the southern margin of the Japan sea north basin. It is aimed at tracing the flow path of turbidites that are assumed to have deposited in response to the 1993 Hokkaido-Nansei-oki earthquake. <span class="hlt">Magnetic</span> remanence was used for reorientation to the geographic coordinates. Magnetomineralogical investigations including low-temperature magnetometry, <span class="hlt">magnetic</span> hysteresis loops and isothermal remanent <span class="hlt">magnetization</span> (IRM) acquisition experiments indicate that pseudosingle domain to multidomain magnetite is the principal <span class="hlt">magnetic</span> carrier and is, therefore, capable of providing reliable anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) palaeocurrent direction estimates. A well-developed near-horizontal <span class="hlt">magnetic</span> foliation and minimum <span class="hlt">susceptibility</span> axes lying close to vertical are recorded at all sites reflecting an original depositional fabric. Clearly defined <span class="hlt">magnetic</span> lineation was observed at all sites and is considered to reflect the palaeocurrent direction. Down-core changes of <span class="hlt">susceptibility</span> and key AMS parameters show good correspondence to occurrences of turbidite layers marking the increase of input of influx materials. In agreement with results from recent marine surveys and IZANAGI side-scan sonar images, an NNE transportation trend has been estimated for sediments at sites from the Shiribeshi trough with a possible depositing path initiating from the slope bounding the south and southeastern margin down to the trough floor. Similarly, a SSE palaeocurrent direction has been estimated for sediments from the Okushiri basin with evidence for a relatively strong transporting current flowing through the canyons along the steep slope bounding the north and northeastern margins of the basin. The present results agree with the view that slope failure is the most probable mechanism for the down-slope transport</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004GeoJI.157...15A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004GeoJI.157...15A"><span>Flow path of the 1993 Hokkaido-Nansei-oki earthquake seismoturbidite, southern margin of the Japan sea north basin, inferred from anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abdeldayem, A. L.; Ikehara, K.; Yamazaki, T.</p> <p>2004-04-01</p> <p>A <span class="hlt">magnetic</span> fabric analysis has been carried out on standard cube samples from one gravity and three multiple cores extracted from the Shiribeshi trough and Okushiri basin in the southern margin of the Japan sea north basin. It is aimed at tracing the flow path of turbidites that are assumed to have deposited in response to the 1993 Hokkaido-Nansei-oki earthquake. <span class="hlt">Magnetic</span> remanence was used for reorientation to the geographic coordinates. Magnetomineralogical investigations including low-temperature magnetometry, <span class="hlt">magnetic</span> hysteresis loops and isothermal remanent <span class="hlt">magnetization</span> (IRM) acquisition experiments indicate that pseudo-single domain to multidomain magnetite is the principal <span class="hlt">magnetic</span> carrier and is, therefore, capable of providing reliable anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) palaeocurrent direction estimates. A well-developed near-horizontal <span class="hlt">magnetic</span> foliation and minimum <span class="hlt">susceptibility</span> axes lying close to vertical are recorded at all sites reflecting an original depositional fabric. Clearly defined <span class="hlt">magnetic</span> lineation was observed at all sites and is considered to reflect the palaeocurrent direction. Down-core changes of <span class="hlt">susceptibility</span> and key AMS parameters show good correspondence to occurrences of turbidite layers marking the increase of input of influx materials. In agreement with results from recent marine surveys and IZANAGI side-scan sonar images, an NNE transportation trend has been estimated for sediments at sites from the Shiribeshi trough with a possible depositing path initiating from the slope bounding the south and southeastern margin down to the trough floor. Similarly, a SSE palaeocurrent direction has been estimated for sediments from the Okushiri basin with evidence for a relatively strong transporting current flowing through the canyons along the steep slope bounding the north and northeastern margins of the basin. The present results agree with the view that slope failure is the most probable mechanism for the down-slope transport</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhRvB..83q4514P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhRvB..83q4514P"><span>Vortex dynamics and irreversibility line in optimally doped SmFeAsO0.8F0.2 from ac <span class="hlt">susceptibility</span> and <span class="hlt">magnetization</span> measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Prando, G.; Carretta, P.; de Renzi, R.; Sanna, S.; Palenzona, A.; Putti, M.; Tropeano, M.</p> <p>2011-05-01</p> <p>Ac <span class="hlt">susceptibility</span> and static <span class="hlt">magnetization</span> measurements were performed in the optimally doped SmFeAsO0.8F0.2 superconductor. The field-temperature phase diagram of the superconducting state was drawn, and, in particular, the features of the flux lines were derived. The dependence of the intragrain depinning energy on the <span class="hlt">magnetic</span> field intensity was derived in the thermally activated flux-creep framework, enlightening a typical 1/H dependence in the high-field regime. The intragrain critical current density was extrapolated in the zero-temperature and zero-<span class="hlt">magnetic</span>-field limit, showing a remarkably high value Jc0(0)~2×107 A/cm2, which demonstrates that this material is rather interesting for potential future technological applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4790912','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4790912"><span>Quantitative <span class="hlt">Susceptibility</span> Mapping-Based Microscopy of <span class="hlt">Magnetic</span> Resonance Venography (QSM-mMRV) for In Vivo Morphologically and Functionally Assessing Cerebromicrovasculature in Rat Stroke Model</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hsieh, Meng-Chi; Tsai, Ching-Yi; Liao, Min-Chiao; Yang, Jenq-Lin; Su, Chia-Hao; Chen, Jyh-Horng</p> <p>2016-01-01</p> <p>Abnormal cerebral oxygenation and vessel structure is a crucial feature of stroke. An imaging method with structural and functional information is necessary for diagnosis of stroke. This study applies QSM-mMRV (quantitative <span class="hlt">susceptibility</span> mapping-based microscopic <span class="hlt">magnetic</span> resonance venography) for noninvasively detecting small cerebral venous vessels in rat stroke model. First, <span class="hlt">susceptibility</span> mapping is optimized and calculated from <span class="hlt">magnetic</span> resonance (MR) phase images of a rat brain. Subsequently, QSM-mMRV is used to simultaneously provide information on microvascular architecture and venous oxygen saturation (SvO2), both of which can be used to evaluate the physiological and functional characteristics of microvascular changes for longitudinally monitoring and therapeutically evaluating a disease model. Morphologically, the quantification of vessel sizes using QSM-mMRV was 30% smaller than that of <span class="hlt">susceptibility</span>-weighted imaging (SWI), which eliminated the overestimation of conventional SWI. Functionally, QSM-mMRV estimated an average SvO2 ranging from 73% to 85% for healthy rats. Finally, we also applied QSM to monitor the revascularization of post-stroke vessels from 3 to 10 days after reperfusion. QSM estimations of SvO2 were comparable to those calculated using the pulse oximeter standard metric. We conclude that QSM-mMRV is useful for longitudinally monitoring blood oxygen and might become clinically useful for assessing cerebrovascular diseases. PMID:26974842</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JESS..123..351P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JESS..123..351P"><span>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) studies of Campanian-Maastrichtian sediments of Ariyalur Group, Cauvery Basin, Tamil Nadu, India: An appraisal to Paleocurrent directions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Papanna, G.; Venkateshwarlu, M.; Periasamy, V.; Nagendra, R.</p> <p>2014-03-01</p> <p>Oriented samples of sediments from Ariyalur Group, Cauvery Basin, south India, were studied for low field anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) measurements to unravel the <span class="hlt">magnetic</span> fabrics and paleocurrent directions. The results of AMS parameters of the sediments indicate primary depositional fabrics for Sillakkudi, Ottakovil and Kallamedu sandstone formations and secondary fabric for Kallankurichchi limestone formation. The obtained low degree of anisotropy ( P j ), oblate shape AMS ellipsoid and distribution of maximum ( K 1) and minimum ( K 3) <span class="hlt">susceptibility</span> axes on equal area projection confirm the primary sedimentary fabric for Sillakkudi, Ottakovil and Kallamedu Formations. In the case of ferruginous, lower arenaceous, Gryphaea limestone and upper arenaceous limestone beds of Kallankurichchi Formation have recorded more than one fabric. The observed AMS parameters like shape factor ( T) (prolate to oblate), q value and random distribution of minimum ( K 3) and maximum ( K 1) <span class="hlt">susceptibility</span> axes are supported for secondary fabrics in Kallankurichchi Formation as a result of post-depositional processes. Based on petrographic studies, it can be established that K 1 AMS axis of biotite mineral could represent the flow direction. The established paleocurrent direction for Sillakkudi is NW-SE direction while Ottakovil and Kallamedu Formations recorded NE-SW direction. Overall the paleoflow directions observed for Ariyalur Group is NE-SW to NW-SE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JMMM..375....1A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JMMM..375....1A"><span><span class="hlt">Magnetism</span> variations and <span class="hlt">susceptibility</span> hysteresis at the metal-insulator phase transition temperature of VO2 in a composite film containing vanadium and tungsten oxides</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Akande, Amos A.; Rammutla, Koena E.; Moyo, Thomas; Osman, Nadir S. E.; Nkosi, Steven S.; Jafta, Charl J.; Mwakikunga, Bonex W.</p> <p>2015-02-01</p> <p>We report on the <span class="hlt">magnetic</span> property of 0.67-WO3+0.33-VOx mixture film deposit on the corning glass substrate using the chemical sol-gel and atmospheric pressure chemical vapor deposition (APCVD) methods. The XRD and Raman spectroscopy confirm species of both materials, and the morphological studies with FIB-SEM and TEM reveal segregation of W and V atoms. XPS reveals that V4+ from VO2 forms only 11% of the film; V3+ in the form of V2O3 form 1% of the film, 21% is V5+ from V2O5 and 67% is given to W6+ from WO3. The analysis of the ESR data shows some sharp changes in the <span class="hlt">magnetism</span> near the metal-to-insulator (MIT), which could be theoretically interpreted as the ordering or alignment of electron spins from net moment nature to parallel alignment of <span class="hlt">magnetic</span> moment. The derivatives of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> established the thermally induced <span class="hlt">magnetic</span> property: two distinct transitions of 339 K for heating data and 338 K for cooling data for 151.2 mT field were obtained. Similar results were also obtained for 308.7 mT field, 336 K for heating data and 335 K for cooling data. VSM results confirm a paramagnetic phase with a small amount of <span class="hlt">magnetically</span> ordered phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJAEO..50..159C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJAEO..50..159C"><span>Determining surface <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of loess-paleosol sections based on spectral features: Application to a UHD 185 hyperspectral image</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cui, Jing; Zhang, Shimin; Zhang, Jingfa; Liu, Xudong; Ding, Rui; Liu, Hanyong</p> <p>2016-08-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (MS) records of loess-paleosol sequences have been considered a measure of the degree of pedogenic activity and are considered to be excellent proxies for terrestrial climatic fluctuations. However, the MS of single (vertical) path variations occasionally represents site-specific influences rather than monsoonal changes (depending on the position of the path). Few studies have used remote sensing techniques to map the surface MS information of loess-paleosol sections. Hyperspectral techniques provide an efficient, economical and quantitative alternative. In this study, stepwise regression was used to build MS estimation models based on spectral features. Six MS models based on spectral features were established. Test datasets indicated that our models are very successful, all resulting in R2 > 0.92 and RMSEs ranging from 4.5736 to 6.80475. The slope change between 810 nm and 880 nm (b880/b810) observed in all models played an important role in MS estimation. Models 5 and 6 have higher RMSEs and relatively lower SAM values, although the R2 values are both above 0.95. The RMSEs of the first four models are similar. Therefore, the first four models were thought to be more stable and useful. UHD 185, a new generation of commercial hyperspectral imaging sensor, was used for surface MS mapping of a loess-paleosol section by model 1 and model 2. The MS map corresponded well to the loess sequences. The MS values obtained from the UHD 185 data are convincing and consistent with the measured data (R2 > 0.85). The trend in changing MS values is clear, suggesting that model 1 and model 2 could produce reasonable loess-paleosol section surface maps from the UHD 185 image, although there is a linear offset between the estimated MS and the measured MS. The methodology proposed here can be used to map MS on a much larger scale. Because of the limit of the spectral range, the performances of model 3 and model 4 with the image were not discussed. However</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18..343D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18..343D"><span>The anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) and paleomagnetic results from Lower Triassic sequence of West Spitsbergen Fold-and-Thrust Belt - case study.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dudzisz, Katarzyna; Szaniawski, Rafał; Michalski, Krzysztof; Manby, Geoffrey</p> <p>2016-04-01</p> <p>Ninety-three oriented rock samples from 12 sites (ca. 450 specimens) located in the Lower Triassic Vardebukta Formation were analyzed. The samples were collected from the Hornsund - Sørkapp area in the southern part of West Spitsbergen Fold and Thrust Belt (WSFTB). The aim of this study was to test the anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) method for the determination of tectonic paleostress pattern during the formation of WSFTB. The principal ferro- and paramagnetic minerals were also identified and their influence on the <span class="hlt">magnetic</span> suceptibility was assessed. The NRM structure was determined in an attempt to link the remagnetization episodes with the well recognized tectono-thermal events related to WSFTB evolution. The results suggest that the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> is controlled mainly by the paramagnetic minerals evidenced by the wide range of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> values (20 - 400*10-6 SI). Only in one site, COND1, were the ferromagnetic minerals more dominant. A considerable variation in the shape of the AMS ellipsoids was noted. In eleven sites a normal <span class="hlt">magnetic</span> fabric of sedimentary origin was detected which was associated with a relatively good clustering of the maximum AMS axes, caused by the tectonic strain. Samples with normal fabric reveal the presence of strong foliation parallel to the bedding plane. The orientation of the <span class="hlt">magnetic</span> lineation, which indicates the maximum tectonic strain, approximates the regional structural NNW-SSE trend of the WSFTB. These results seem to support an orthogonal compression model for the formation of the WSFTB. Furthermore, the correspondence of the orientation of the maximum AMS axes with regional WSFTB structural trend is in conflict with interpretations assuming a strong strike - slip regime during WSFTB tectogenesis. The remaining two sites had mixed and inverted fabrics, the latter probably arising from the presence of iron-bearing carbonates in the samples. Preliminary palaeomagnetic results show that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.B11D0476E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.B11D0476E"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> mapping of fly ash in soil samples near a coal-burning power plant in Pointe Coupee Parish, Louisiana.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Elhelou, O.; Richter, C.</p> <p>2015-12-01</p> <p>Atmospheric deposition of pollutants is a major health and environmental concern. In a 2010 study, the CATF attributed over 13,000 deaths each year to fly ash and other fine particles emitted by U.S. coal-burning power plants. The <span class="hlt">magnetic</span> properties of fly ash allows for mapping an area suspect of PM pollution faster and more efficiently than by conducting chemical analysis as the former alternative. The objective of this study is to detect the presence of <span class="hlt">magnetic</span> particles related to the migration of fly ash from a nearby coal power plant over parts of Pointe Coupee Parish, LA. This is based on the idea that the fly ash that is released into the atmosphere during the coal burning process contains heavy metals and <span class="hlt">magnetic</span> particles in the form of ferrospheres, which can be used to trace back to the source. Maps of the top and sub soil were generated to differentiate the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> values of the heavy metals potentially attributed to the migration and settling of fly ash onto the surface from any pre-existing or naturally occurring heavy metals in the sub soil. A 60 km2 area in Pointe Coupee Parish was investigated in approximately 0.5 km2 subsets. The area in Pointe Coupee Parish, LA was selected because land use is predominantly rural with the Big Cajun II power plant as the main contributor for air borne contaminants. Samples of fly ash obtained directly from the source below one of the power plant's precipitators were also analyzed to verify the field and laboratory analysis. Contour maps representing the spatial distribution of fly ash over Pointe Coupee, LA, along with histograms of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> values, and chemical analysis all indicate a correlation between the proximity to the power plant and the predominant wind direction. Acquisition curves of the isothermal remnant <span class="hlt">magnetization</span> demonstrate the presence of predominantly low coercivity minerals (magnetite) with a small amount of a high-coercivity phase. The microstructure of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED572321.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED572321.pdf"><span>Young Indigenous Students en Route to <span class="hlt">Generalising</span> Growing Patterns</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Miller, Jodie</p> <p>2016-01-01</p> <p>This paper presents a hypothesised learning trajectory for a Year 3 Indigenous student en route to <span class="hlt">generalising</span> growing patterns. The trajectory emerged from data collected across a teaching experiment (students n = 18; including a pre-test and three 45-minute mathematics lessons) and clinical interviews (n = 3). A case study of one student is…</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGP...106..108R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGP...106..108R"><span><span class="hlt">Generalised</span> time functions and finiteness of the Lorentzian distance</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rennie, Adam; Whale, Ben E.</p> <p>2016-08-01</p> <p>We show that finiteness of the Lorentzian distance is equivalent to the existence of <span class="hlt">generalised</span> time functions with gradient uniformly bounded away from light cones. To derive this result we introduce new techniques to construct and manipulate achronal sets. As a consequence of these techniques we obtain a functional description of the Lorentzian distance extending the work of Franco (2010) and Moretti (2003).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Abduction&pg=5&id=EJ748025','ERIC'); return false;" href="http://eric.ed.gov/?q=Abduction&pg=5&id=EJ748025"><span>On <span class="hlt">Generalising</span> from Single Case Studies: Epistemological Reflections</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Evers, Colin W.; Wu, Echo H.</p> <p>2006-01-01</p> <p>The aim of this paper is to explore the conditions under which <span class="hlt">generalisation</span> from single case studies, in the sense of making inferences concerning a wider class of phenomena beyond a case, is reasonable. Two sets of conditions, in particular, provide the basis for our consideration of this issue. The first is an exploration of the impressive…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H41J..07L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H41J..07L"><span>Indications of Coupled Carbon and Iron Cycling at a Hydrocarbon-Contaminated Site from Time-Lapse <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> (MS) Profiles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lund, A.; Slater, L. D.; Atekwana, E. A.; Rossbach, S.; Ntarlagiannis, D.; Bekins, B. A.</p> <p>2015-12-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (MS) data acquired at hydrocarbon contaminated sites have documented enhanced MS within the smear zone (zone of water table fluctuation at hydrocarbon contaminated location) coincident with the free phase (mobile or free liquids moving down through the unsaturated zone independent of the direction of flow of the groundwater or surface water) hydrocarbon plume These studies suggest that <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> can be used as a tool to: (1) infer regions of hydrocarbon contamination, and (2) investigate intrinsic bioremediation by iron reducing bacteria. We performed a campaign of time-lapse MS monitoring at the National Crude Oil Spill Fate and Natural Attenuation Research Site (Bemidji, MN) between July 2011 and August 2015. This highly instrumented site has multiple boreholes installed through the free phase, dissolved phase and uncontaminated portions of the aquifer impacted by an oil spill resulting from a pipeline rupture in 1979. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> (MS) data acquired in 2011 showed that MS values in the smear zone are higher than in the dissolved phase plume and background, leading to the hypothesis that MS measurements could be used to monitor the long-term progress of biodegradation at the site. However, repeated MS data acquired in 2014 and 2015 showed strong changes in the character of the MS signal in the smear zone with multiple free phase contamination locations showing a strong suppression of the signal relative to that observed in 2011. Other locations in the dissolved phase of the plume show evidence for vertical migration of the zone of enhanced MS, possibly due to changes in the redox profiles driven by hydrology. Such changes in the MS signal are hypothesized to result from either variations in Fe(II)/Fe(III) ratios in the magnetite or changes in the magnetite concentration associated with coupled carbon and iron biogeochemistry. This work is generating a unique time-lapse geophysical dataset providing information on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26156571','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26156571"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> as a direct measure of oxidation state in LiFePO4 batteries and cyclic water gas shift reactors.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kadyk, Thomas; Eikerling, Michael</p> <p>2015-08-14</p> <p>The possibility of correlating the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> to the oxidation state of the porous active mass in a chemical or electrochemical reactor was analyzed. The <span class="hlt">magnetic</span> permeability was calculated using a hierarchical model of the reactor. This model was applied to two practical examples: LiFePO4 batteries, in which the oxidation state corresponds with the state-of-charge, and cyclic water gas shift reactors, in which the oxidation state corresponds to the depletion of the catalyst. In LiFePO4 batteries phase separation of the lithiated and delithiated phases in the LiFePO4 particles in the positive electrode gives rise to a hysteresis effect, i.e. the <span class="hlt">magnetic</span> permeability depends on the history of the electrode. During fast charge or discharge, non-uniform lithium distributionin the electrode decreases the hysteresis effect. However, the overall sensitivity of the <span class="hlt">magnetic</span> response to the state-of-charge lies in the range of 0.03%, which makes practical measurement challenging. In cyclic water gas shift reactors, the sensitivity is 4 orders of magnitude higher and without phase separation, no hysteresis occurs. This shows that the method is suitable for such reactors, in which large changes of the <span class="hlt">magnetic</span> permeability of the active material occurs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19257001','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19257001"><span>High-temperature expansion of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and higher moments of the correlation function for the two-dimensional XY model.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Arisue, H</p> <p>2009-01-01</p> <p>We calculate the high-temperature series of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and the second and fourth moments of the correlation function for the XY model on the square lattice to order beta;{33} by applying the improved algorithm of the finite lattice method. The long series allow us to estimate the inverse critical temperature as beta_{c}=1.1200(1) , which is consistent with the most precise value given previously by the Monte Carlo simulation. The critical exponent for the multiplicative logarithmic correction is evaluated to be theta=0.054(10) , which is consistent with the renormalization group prediction of theta=1/16 .</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JPhCS.391a2111Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JPhCS.391a2111Y"><span>Hydrostatic Pressure Study on 3-K Phase Superconductivity in Sr2RuO4-Ru Eutectic Crystals by AC <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yaguchi, Hiroshi; Watanabe, Hiromichi; Sakaue, Akira</p> <p>2012-12-01</p> <p>We have investigated the effect of hydrostatic pressure on 3-K phase superconductivity in Sr2RuO4-Ru eutectic crystals by means of AC <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements. We have found that the application of hydrostatic pressure suppresses the superconducting transition temperature Tc of the 3-K phase with a pressure coefficient of dTc/dP ≈ -0.2 K/GPa, similar to the case of the 1.5-K phase. We have also observed that the effect of hydrostatic pressure on the 3-K phase seems to be elastic whilst that of uniaxial pressure is plastic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoJI.208..663Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoJI.208..663Z"><span>New insights into the palaeoclimatic interpretation of the temperature dependence of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and <span class="hlt">magnetization</span> of Mid-Late Pleistocene loess/palaeosols in Central Asia and the Chinese Loess Plateau</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zan, Jinbo; Fang, Xiaomin; Yan, Maodu; Li, Bingshuai</p> <p>2017-02-01</p> <p>The temperature dependence of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (χ-T curves) and <span class="hlt">magnetization</span> (M-T curves) has been used as a routine rock <span class="hlt">magnetic</span> tool to characterize the <span class="hlt">magnetic</span> mineralogy and <span class="hlt">magnetic</span> granulometry of Chinese loess/palaeosols. However, palaeoclimatic interpretation of these thermomagnetic analyses remains controversial. In the present study, total organic carbon (TOC), thermomagnetic and low-temperature <span class="hlt">magnetic</span> experiments on Mid-Late Pleistocene loess/palaeosols in Central Asia and the Chinese Loess Plateau (CLP) have been conducted. We found that the M (T) cooling curves at room temperature were mostly lower than the corresponding heating curves, whereas for the χ (T) analyses the cooling curves at room temperature were always much higher than the heating curves. Low-temperature <span class="hlt">magnetic</span> measurements demonstrated that a large amount of superparamagnetic ferrimagnetic particles were produced during the thermal treatment and resulted in the aforementioned differences. This finding further indicated that the use of the M-T curves to estimate the relative content of maghemite in the loess/palaeosols from the CLP was problematic. In addition, a positive correlation exists between the TOC and the frequency-dependent <span class="hlt">susceptibility</span> (χFD) in the CLP, suggesting that stronger pedogenesis would result in the simultaneous increase in the content of both maghemite and organic matter. Consequently, the parameters ▵χ1 (representing the relative content of pedogenic maghemite), ▵χ2 ([χph - χ] +▵χ1) and χph (related to the organic matter concentration), which can be calculated from the χ-T analyses, can potentially be used as new indicators of pedogenesis and palaeoclimate in Central Asia and the CLP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.tmp..459Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.tmp..459Z"><span>New insights into the paleoclimatic interpretation of the temperature dependence of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and <span class="hlt">magnetization</span> of Mid-Late Pleistocene loess/palaeosols in Central Asia and the Chinese Loess Plateau</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zan, Jinbo; Fang, Xiaomin; Yan, Maodu; Li, Bingshuai</p> <p>2016-11-01</p> <p>The temperature dependence of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (χ-T curves) and <span class="hlt">magnetization</span> (M-T curves) has been used as a routine rock <span class="hlt">magnetic</span> tool to characterize the <span class="hlt">magnetic</span> mineralogy and <span class="hlt">magnetic</span> granulometry of Chinese loess/palaeosols. However, paleoclimatic interpretation of these thermomagnetic analyses remains controversial. In the present study, total organic carbon (TOC), thermomagnetic and low-temperature <span class="hlt">magnetic</span> experiments on Mid-Late Pleistocene loess/palaeosols in Central Asia and the Chinese Loess Plateau (CLP) have been conducted. We found that the M (T) cooling curves at room temperature were mostly lower than the corresponding heating curves, whereas for the χ (T) analyses the cooling curves at room temperature were always much higher than the heating curves. Low-temperature <span class="hlt">magnetic</span> measurements demonstrated that a large amount of superparamagnetic ferrimagnetic particles were produced during the thermal treatment and resulted in the aforementioned differences. This finding further indicated that the use of the M - T curves to estimate the relative content of maghemite in the loess/paleosols from the CLP was problematic. In addition, a positive correlation exists between the TOC and the frequency-dependent <span class="hlt">susceptibility</span> (χFD) in the CLP, suggesting that stronger pedogenesis would result in the simultaneous increase in the content of both maghemite and organic matter. Consequently, the parameters △χ1 (representing the relative content of pedogenic maghemite), △χ2 ([χph-χ] +△χ1) and χph (related to the organic matter concentration), which can be calculated from the χ - T analyses, can potentially be used as new indicators of pedogenesis and paleoclimate in Central Asia and the CLP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760061903&hterms=permeability+soil&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dpermeability%2Bsoil','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760061903&hterms=permeability+soil&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dpermeability%2Bsoil"><span>The frequency dependence of the viscous component of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of lunar rock and soil samples</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hanneken, J. W.; Vant-Hull, L. L.; Carnes, J. G.</p> <p>1976-01-01</p> <p>The <span class="hlt">susceptibility</span> of two lunar samples (a soil and a low metamorphic grade breccia) has been measured in a weak field - 0.001 Oe - and as a function of frequency from 0.032 to 1.0 Hz. The measurements were made using a superconducting magnetometer. The results show that the <span class="hlt">susceptibility</span> decreases linearly with the log of frequency. This observation is in agreement with a theoretical model for viscous decay based on the Neel theory of single-domain and superparamagnetic grains. The relation derived agrees with a model in which there is a uniform distribution of relaxation times.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008APS..MAR.K1052H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008APS..MAR.K1052H"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> and Mössbauer studies of [FeX3](ClO4)2.H2O with X = bpz, bpy, phen or tpy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ho, J. C.; Hamdeh, H. H.; Kirgan, R.; Rillema, D. P.</p> <p>2008-03-01</p> <p><span class="hlt">Magnetic</span> studies have been made on several tris-chelated iron complex compounds [FeX3](ClO4)2.H2O with aromatic nitrogen heterocycle ligands X = bpz (2,2'-bipyrazine), bpy (2,2'-bipyridine), phen (1,10-phenanthroline) or tpy (2,2':6,2''-terpyridine). SQUID data (2-300 K and 0.01-1 T) yielded small effective <span class="hlt">magnetic</span> moments, which are characteristic of low-spin Fe(II), in agreement with the isomer shift and quadrupole splitting values from Mössbauer measurements (4-300 K, 0-5 T). Meanwhile, apart from the expected diamagnetism, a positive term of temperature-independent paramagnetic <span class="hlt">susceptibility</span> prevails in most cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28346006','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28346006"><span><span class="hlt">Magnetic</span> resonance imaging <span class="hlt">susceptibility</span> artifacts in the cervical vertebrae and spinal cord related to monocortical screw-polymethylmethacrylate implants in canine cadavers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jones, Brian G; Fosgate, Geoffrey T; Green, Eric M; Habing, Amy M; Hettlich, Bianca F</p> <p>2017-04-01</p> <p>OBJECTIVE To characterize and compare MRI <span class="hlt">susceptibility</span> artifacts related to titanium and stainless steel monocortical screws in the cervical vertebrae and spinal cord of canine cadavers. SAMPLE 12 canine cadavers. PROCEDURES Cervical vertebrae (C4 and C5) were surgically stabilized with titanium or stainless steel monocortical screws and polymethylmethacrylate. Routine T1-weighted, T2-weighted, and short tau inversion recovery sequences were performed at 3.0 T. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> artifacts in 20 regions of interest (ROIs) across 4 contiguous vertebrae (C3 through C6) were scored by use of an established scoring system. RESULTS Artifact scores for stainless steel screws were significantly greater than scores for titanium screws at 18 of 20 ROIs. Artifact scores for titanium screws were significantly higher for spinal cord ROIs within the implanted vertebrae. Artifact scores for stainless steel screws at C3 were significantly less than at the other 3 cervical vertebrae. CONCLUSIONS AND CLINICAL RELEVANCE Evaluation of routine MRI sequences obtained at 3.0 T revealed that <span class="hlt">susceptibility</span> artifacts related to titanium monocortical screws were considered mild and should not hinder the overall clinical assessment of the cervical vertebrae and spinal cord. However, mild focal artifacts may obscure small portions of the spinal cord or intervertebral discs immediately adjacent to titanium screws. Severe artifacts related to stainless steel screws were more likely to result in routine MRI sequences being nondiagnostic; however, artifacts may be mitigated by implant positioning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20086326','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20086326"><span>Evaluation of the <span class="hlt">susceptibility</span> artifacts and tissue injury caused by implanted microchips in dogs on 1.5 T <span class="hlt">magnetic</span> resonance imaging.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Saito, Miyoko; Ono, Shin; Kayanuma, Hideki; Honnami, Muneki; Muto, Makoto; Une, Yumi</p> <p>2010-05-01</p> <p>Performing <span class="hlt">magnetic</span> resonance imaging (MRI) in patients with a metallic implant raises concern over the potential complications, including <span class="hlt">susceptibility</span> artifacts, implant migration, and heat injury. The purpose of this study was to investigate these complications in dogs with implanted microchips by evaluating MR images and the histopathological changes after 1.5 Tesla (T) MRI. Five dogs underwent microchip implantation in the cervicothoracic area. One month later, the area was imaged using 1.5T MRI in three dogs. The microchips were removed surgically together with the surrounding tissue in all dogs. There was significant signal loss and image distortion over a wide range around the area where the microchip was implanted. This change was consistent with <span class="hlt">susceptibility</span> artifacts, which rendered the affected area including the spinal cord undiagnostic. The artifact was more extensive in T2*-weighted images (gradient-echo) and less extensive in proton density-weighted images (fast spin-echo with short echo time). Histopathologically, all microchips were well-encapsulated with granulation tissue, and there were no evidence of migration of microchips. Cell debris and a moderate number of degenerated cells with fibrin were seen in the inner layer of the granulation tissue in each dog that underwent MRI. These changes were very subtle and did not seem to be clinically significant. The results of this study suggest that, in 1.5T MRI, <span class="hlt">susceptibility</span> artifacts produced by implanted microchips can be marked, although the dogs with implants appeared to be scanned safely.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4192858','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4192858"><span>Learnability and <span class="hlt">generalisation</span> of Arabic broken plural nouns</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dawdy-Hesterberg, Lisa Garnand; Pierrehumbert, Janet Breckenridge</p> <p>2014-01-01</p> <p>The noun plural system in Modern Standard Arabic lies at a nexus of critical issues in morphological learnability. The suffixing “sound” plural competes with as many as 31 non-concatenative “broken” plural patterns. Our computational analysis of singular–plural pairs in the Corpus of Contemporary Arabic explores what types of linguistic information are statistically relevant to morphological <span class="hlt">generalisation</span> for this highly complex system. We show that an analogical approach with the <span class="hlt">generalised</span> context model is highly successful in predicting the plural form for any given singular form. This model proves to be robust to variation, as evidenced by its stability across 10 rounds of cross-validation. The predictive power is carried almost entirely by the CV template, a representation which specifies a segment's status as a consonant or vowel only, providing further support for the abstraction of prosodic templates in the Arabic morphological system as proposed by McCarthy and Prince. PMID:25346932</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1027356','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1027356"><span>Prolactin and gonadotrophin changes following <span class="hlt">generalised</span> and partial seizures.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dana-Haeri, J; Trimble, M r; Oxley, J</p> <p>1983-01-01</p> <p>Postictal values of prolactin, LH and FSH have been recorded in patients with both <span class="hlt">generalised</span> tonic-clonic and partial seizures. Elevations of prolactin and LH were seen immediately and at 20 minutes in males and females with <span class="hlt">generalised</span> attacks. At sixty minutes values for prolactin had fallen to baseline levels, but LH remained elevated. FSH values were increased in females only, at twenty and sixty minutes. Following partial seizures prolactin was elevated, especially with complex partial seizures, at twenty minutes. These results are discussed in the light of known electrophysiological mechanisms relating to partial seizures, and clinical guidelines for the use of neurohormonal tests in the evaluation of seizures are suggested. PMID:6405014</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989BVol...51..299W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989BVol...51..299W"><span>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> in welded tuffs: application to a welded-tuff dyke in the tertiary Trans-Pecos Texas volcanic province, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wolff, John A.; Ellwood, Brooks B.; Sachs, Scott D.</p> <p>1989-06-01</p> <p>Consideration of published anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) studies on welded ignimbrites suggests that AMS fabrics are controlled by groundmass microlites distributed within the existing tuff fabric, the sum result of directional fabrics imposed by primary flow lineation, welding, and (if relevant) rheomorphism. AMS is a more sensitive indicator of fabric elements within welded tuffs than conventional methods, and usually yields primary flow azimuth estimates. Detailed study of a single densely welded tuff sample demonstrates that the overall AMS fabric is insensitive to the relative abundances of fiamme, matrix and lithics within individual drilled cores. AMS determinations on a welded-tuff dyke occurring in a choked vent in the Trans-Pecos Texas volcanic field reveals a consistent fabric with a prolate element imbricated with respect to one wall of the dyke, while total <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and density exhibit axially symmetric variations across the dyke width. The dyke is interpreted to have formed as a result of agglutination of the erupting mixture on a portion of the conduit wall as it failed and slid into the conduit, followed by residual squeezing between the failed block and in situ wallrock. Irrespective of the precise mechanism, widespread occurrence of both welded-tuff dykes and point-welded, aggregate pumices in pyroclastic deposits may imply that lining of conduit walls by agglutionation during explosive volcanic eruptions is a common process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18383301','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18383301"><span>Water chemical shift in 1H NMR of red cells: effects of pH when transmembrane <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> differences are low.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Larkin, Timothy J; Bubb, William A; Kuchel, Philip W</p> <p>2008-04-01</p> <p>The (1)H magic angle spinning (MAS) NMR spectrum of water in erythrocyte suspensions shows peaks from each of the intracellular and extracellular water pools. The splitting is a true chemical shift and is brought about by the elimination of water exchange under MAS conditions due to physical separation of the two water populations. The size of the chemical shift difference is determined by the concentration of intracellular protein affecting the average extent of hydrogen bonding of water. We present here a model of the chemical shift behavior for water in erythrocytes under normal high-resolution NMR conditions based on results from MAS experiments on these cells exposed to different pH and osmotic conditions. The model accurately predicts the chemical shift of water for a static sample, and the results demonstrate that in high-resolution NMR experiments the chemical shift of water will appear to be invariant if differences in <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> across the cell membrane are minimal (<10% of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of water). Thus, changes in the shape and chemical shift of the water resonance are not due to pH changes in the physiological range. The findings are fundamental to an interpretation of the mechanism of chemical shift effects on the water resonance that may occur in functional MRI.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21072513','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21072513"><span>Covalence-induced stabilization of an intermediate-spin state and the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of LaCoO{sub 3}</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ovchinnikov, S. G. Orlov, Yu. S.</p> <p>2007-03-15</p> <p>The energies of terms with spins S = 0, 1, 2 have been found using exact diagnoalization of the multielectron Hamiltonian of a multiband pd model for the CoO{sub 6} cluster. Co (e{sub g} orbital)-O hops, which form the covalent {sigma} bond, are shown to decrease the energy of the state (IS) with an intermediate spin (S = 1) as compared to the energy of the state (LS) with a low spin (S = 0). An analogue of the Tanabe-Sugano diagram that takes into account the covalence of the CoO{sub 6} cluster is constructed. The state with S = 1 is shown to be a ground state at certain model parameters. An increase in temperature is established to decrease the crystal field and, thus, favors the transition of the ground state from LS to IS at T = 100 K and the transition of the IS ground state to a state (HS) with a high spin (S = 2) at T = 550 K. The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of LaCoO{sub 3} is calculated with allowance for the LS, IS, and HS states and for the fact that the HS state exhibits threefold orbital degeneracy of the t{sub 2g} shell, which results in an effective orbital moment L = 1 and the importance of spin-orbit interaction. The behavior of this <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> agrees well with the experimental x(T) dependence of LaCoO{sub 3}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhRvB..78v4523P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhRvB..78v4523P"><span>Granularity and vortex dynamics in LaFeAsO0.92F0.08 probed by harmonics of the ac <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Polichetti, Massimiliano; Adesso, Maria G.; Zola, Danilo; Luo, Jianlin; Chen, G. F.; Li, Zheng; Wang, N. L.; Noce, Canio; Pace, Sandro</p> <p>2008-12-01</p> <p>Fundamental and higher harmonics of the ac <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> have been measured on LaFeAsO0.92F0.08 samples as a function of the temperature, at various amplitudes and frequencies of the ac <span class="hlt">magnetic</span> field, with a small superimposed dc field parallel to the ac field. The granularity of the samples has been investigated and the intergrain and intragrain contributions have been clearly individuated looking at both the first and the third harmonics. The vortex dynamics has been also analyzed, and a comparison with the <span class="hlt">magnetic</span> behavior of both the MgB2 and the cuprate superconductors has been performed. Some vortex dissipative phenomena, i.e., the thermally activated flux flow and the flux creep, have been detected in the presented experimental data, similar to what have been obtained on YBCO. Nevertheless, although the general behavior is similar, several differences have been also evidenced between these different classes of superconductors, mainly in the third harmonics. We infer that different vortex dynamics has to be included into the analysis of the <span class="hlt">magnetic</span> response in this iron-based material.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1982E%26PSL..59..303E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982E%26PSL..59..303E"><span>Estimates of flow direction for calc-alkaline welded tuffs and paleomagnetic data reliability from anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements: Central San Juan Mountains, southwest Colorado</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ellwood, Brooks B.</p> <p>1982-07-01</p> <p>Flow directions are estimated from the measurement of the <span class="hlt">magnetic</span> fabric of 106 samples, collected at 18 sites in four welded tuff units in the central San Juan Mountains of southern Colorado. The estimates assume that the tuffs generally flowed directly away from the extrusive vents and that the lineations of <span class="hlt">magnetic</span> grains within the tuffs represent the flow direction at individual sites. Errors in the estimation may arise from topographic variation, rheomorphism (post-emplacement mass flow) within the tuff, and other factors. <span class="hlt">Magnetic</span> lineation is defined as the site mean anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> maximum azimuth. A test on the flow directions for individual units is based on the projection of lineation azimuths and their intersection within or near the known source caldera for the tuff. This test is positive for the four units examined. Paleomagnetic results for these tuffs are probably reliable indicators of the geomagnetic field direction in southwest Colorado, during the time (28.2-26.5 Ma) of emplacement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5114565','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5114565"><span><span class="hlt">Generalised</span> monogamy relation of convex-roof extended negativity in multi-level systems</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tian, Tian; Luo, Yu; Li, Yongming</p> <p>2016-01-01</p> <p>In this paper, we investigate the <span class="hlt">generalised</span> monogamy inequalities of convex-roof extended negativity (CREN) in multi-level systems. The <span class="hlt">generalised</span> monogamy inequalities provide the upper and lower bounds of bipartite entanglement, which are obtained by using CREN and the CREN of assistance (CRENOA). Furthermore, we show that the CREN of multi-qubit pure states satisfies some monogamy relations. Additionally, we test the <span class="hlt">generalised</span> monogamy inequalities for qudits by considering the partially coherent superposition of a <span class="hlt">generalised</span> W-class state in a vacuum and show that the <span class="hlt">generalised</span> monogamy inequalities are satisfied in this case as well. PMID:27857163</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23173573','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23173573"><span><span class="hlt">Generalised</span> pollination systems for three invasive milkweeds in Australia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ward, M; Johnson, S D</p> <p>2013-05-01</p> <p>Because most plants require pollinator visits for seed production, the ability of an introduced plant species to establish pollinator relationships in a new ecosystem may have a central role in determining its success or failure as an invader. We investigated the pollination ecology of three milkweed species - Asclepias curassavica, Gomphocarpus fruticosus and G. physocarpus - in their invaded range in southeast Queensland, Australia. The complex floral morphology of milkweeds has often been interpreted as a general trend towards specialised pollination requirements. Based on this interpretation, invasion by milkweeds contradicts the expectation than plant species with specialised pollination systems are less likely to become invasive that those with more <span class="hlt">generalised</span> pollination requirements. However, observations of flower visitors in natural populations of the three study species revealed that their pollination systems are essentially specialised at the taxonomic level of the order, but <span class="hlt">generalised</span> at the species level. Specifically, pollinators of the two Gomphocarpus species included various species of Hymenoptera (particularly vespid wasps), while pollinators of A. curassavica were primarily Lepidoptera (particularly nymphalid butterflies). Pollinators of all three species are rewarded with copious amounts of highly concentrated nectar. It is likely that successful invasion by these three milkweed species is attributable, at least in part, to their <span class="hlt">generalised</span> pollinator requirements. The results of this study are discussed in terms of how data from the native range may be useful in predicting pollination success of species in a new environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015CG.....84...86N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015CG.....84...86N"><span>An ontological system for interoperable spatial <span class="hlt">generalisation</span> in biodiversity monitoring</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nieland, Simon; Moran, Niklas; Kleinschmit, Birgit; Förster, Michael</p> <p>2015-11-01</p> <p>Semantic heterogeneity remains a barrier to data comparability and standardisation of results in different fields of spatial research. Because of its thematic complexity, differing acquisition methods and national nomenclatures, interoperability of biodiversity monitoring information is especially difficult. Since data collection methods and interpretation manuals broadly vary there is a need for automatised, objective methodologies for the generation of comparable data-sets. Ontology-based applications offer vast opportunities in data management and standardisation. This study examines two data-sets of protected heathlands in Germany and Belgium which are based on remote sensing image classification and semantically formalised in an OWL2 ontology. The proposed methodology uses semantic relations of the two data-sets, which are (semi-)automatically derived from remote sensing imagery, to generate objective and comparable information about the status of protected areas by utilising kernel-based spatial reclassification. This automatised method suggests a <span class="hlt">generalisation</span> approach, which is able to generate delineation of Special Areas of Conservation (SAC) of the European biodiversity Natura 2000 network. Furthermore, it is able to transfer <span class="hlt">generalisation</span> rules between areas surveyed with varying acquisition methods in different countries by taking into account automated inference of the underlying semantics. The <span class="hlt">generalisation</span> results were compared with the manual delineation of terrestrial monitoring. For the different habitats in the two sites an accuracy of above 70% was detected. However, it has to be highlighted that the delineation of the ground-truth data inherits a high degree of uncertainty, which is discussed in this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5338352','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5338352"><span>Working dogs cooperate among one another by <span class="hlt">generalised</span> reciprocity</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gfrerer, Nastassja; Taborsky, Michael</p> <p>2017-01-01</p> <p>Cooperation by <span class="hlt">generalised</span> reciprocity implies that individuals apply the decision rule “help anyone if helped by someone”. This mechanism has been shown to generate evolutionarily stable levels of cooperation, but as yet it is unclear how widely this cooperation mechanism is applied among animals. Dogs (Canis familiaris) are highly social animals with considerable cognitive potential and the ability to differentiate between individual social partners. But although dogs can solve complex problems, they may use simple rules for behavioural decisions. Here we show that dogs trained in an instrumental cooperative task to provide food to a social partner help conspecifics more often after receiving help from a dog before. Remarkably, in so doing they show no distinction between partners that had helped them before and completely unfamiliar conspecifics. Apparently, dogs use the simple decision rule characterizing <span class="hlt">generalised</span> reciprocity, although they are probably capable of using the more complex decision rule of direct reciprocity: “help someone who has helped you”. However, generalized reciprocity involves lower information processing costs and is therefore a cheaper cooperation strategy. Our results imply that <span class="hlt">generalised</span> reciprocity might be applied more commonly than direct reciprocity also in other mutually cooperating animals. PMID:28262722</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14529808','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14529808"><span><span class="hlt">Generalisation</span> of conditioned fear and its behavioural expression in mice.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Laxmi, T Rao; Stork, Oliver; Pape, Hans-Christian</p> <p>2003-10-17</p> <p>Mice are favourite subjects in molecular and genetic memory research and frequently studied with classical fear conditioning paradigms that use an auditory cue (conditioned stimulus, CS(+)) to predict an aversive, unconditioned stimulus (US). Yet the conditions that control fear memory specificity and <span class="hlt">generalisation</span> and their behavioural expression in such conditioned mice have not been analysed systematically. In the current study we addressed these issues in the most widely used mouse strain of behavioural genetics, C57Bl/6. In keeping with findings in other species we demonstrate the dependence of fear memory <span class="hlt">generalisation</span> on training intensity (i.e. both US intensity and the number of CS(+) and US applied) after both excitatory (explicitly paired presentation of CS(+) and US) and inhibitory training (explicitly unpaired presentation of CS(+) and US). Furthermore, inhibitory overtraining was associated with changes of uncued anxiety-like behaviour in a light/dark exploration test, indicative of an emotional sensitisation reaction as consequence of a lack of US predictability. Together our results describe the qualitatively and quantitatively different increases of defensive behaviour in response to conditioned stimuli of different salience and identify training conditions that lead to fear memory <span class="hlt">generalisation</span> and emotional sensitisation in C57Bl/6 inbred mice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.V23E2154P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.V23E2154P"><span>Magma Emplacement at Lemptegy Volcano, Chaîne Des Puys, France based on Structures, Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> and Paleomagnetic Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petronis, M. S.; Delcamp, A.; van Wyk de Vries, B.</p> <p>2009-12-01</p> <p>The Lemptegy volcano is a strombolian double scoria cone in the Chaîne Des Puys, Auvergne, France that erupted about 32,000 years ago. The first cinder cone formed during a trachy-basalt eruption as a satellite vent of the Puy de Gouttes scoria cone. The second edifice developed as an individual eruption soon after. Since 1946, the Lemptegy volcano has been quarried for scoria and today offers unprecedented exposure of the shallow plumbing system (dikes and sills) of a volcano. In order to map the internal flow architecture of the plumbing system, anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) data were collected from ten dikes that occur near the central volcanic edifice. In total, twenty sites were established with one to four sites in each dike and 504 specimens analysed. Our sampling scheme allows for the magma flow pattern to be established within the margins and central part of the intrusions as well as possible along strike flow variation. AMS results yield a remarkably consistent dataset that provides constraints on emplacement. The degree of anisotropy is low to moderate and ellipsoid shapes are dominantly oblate. The maximum <span class="hlt">susceptibility</span> axis (K1) and the imbrications of the <span class="hlt">magnetic</span> foliation planes indicate northwest subhorizontal magma flow. These data are consistent with shear-related structures (e.g., tension gashes, Riedel shears, elongate vesicles) that show magma flow towards the central edifice. In addition, paleomagnetic data from each dike allows for an assessment of the emplacement sequence. We postulate that as each dike was emplaced it may have "shouldered" aside earlier dikes or dikes may have been displaced by localized slumping of the edifice. Based on modern-day scoria cone construction, we assume that the emplacement of the intrusions occurred over a very short time period relative to secular variation and we expect that all dikes record essentially the same geomagnetic field direction. Demagnetization experiments are underway and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23315241','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23315241"><span>Padé approximations for the <span class="hlt">magnetic</span> <span class="hlt">susceptibilities</span> of Heisenberg antiferromagnetic spin chains for various spin values.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Law, J M; Benner, H; Kremer, R K</p> <p>2013-02-13</p> <p>The temperature dependence of the spin <span class="hlt">susceptibilities</span> of S = 1, 3/2, 2, 5/2 and 7/2 Heisenberg antiferromagnetic 1D spins chains with nearest-neighbor coupling was simulated via quantum Monte Carlo calculations, within the reduced temperature range of 0.005 ≤ T* ≤ 100, and fitted to a Padé approximation with deviations between the simulated and fitted data of the same order of magnitude as or smaller than the quantum Monte Carlo simulation error. To demonstrate the practicality of our theoretical findings, we compare these results with the <span class="hlt">susceptibility</span> of the well known 1D chain compound TMMC ([(CH(3))(4)N[MnCl(3)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.3477E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.3477E"><span>A more advantageous and reliable alternative method than widely used anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) for determination of vent locations of ignimbrites: High resolution x-ray tomography (micro-CT)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ersoy, O.; Atici, G.; Aydar, E.; Tatar, Ä.°.</p> <p>2012-04-01</p> <p>Most of knowledge of the flow dynamics and mechanisms of pyroclastic flows comes from examination of their deposits. Until recent date, orientations of flow components such as pumice and lithics were used in order to estimate the vent positions for ignimbrite deposits. Recently, anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) is widely used for determination of flow directions and source positions of ignimbrites. Owing to the fact that individual grains of most minerals are <span class="hlt">magnetically</span> anisotropic, <span class="hlt">magnetic</span> anisotropy works as a petrofabric tool. <span class="hlt">Magnetically</span> anisotropic minerals <span class="hlt">magnetize</span> in certain directions which are governed by primarily by crystallography and/or grain shape. Elongate fragments carried in a pyroclastic density current (ignimbrite) may become aligned by the current motion and by interactions with other grains as well as with the substrate. By accepting that the orientation of long axis are parallel to the flow direction and by assuming that the multi domain <span class="hlt">magnetic</span> minerals have maximum <span class="hlt">susceptibilities</span> parallel to their long axis, the maximum <span class="hlt">susceptibility</span> orientations determined by AMS were accepted as the flow directions. However, this condition is not always in this way, unfortunately. Maximum <span class="hlt">susceptibility</span> orientations perpendicular to the flow axis were determined from AMS measurements from ignimbrite samples having dominantly single domain <span class="hlt">magnetic</span> minerals. Because the maximum <span class="hlt">susceptibility</span> orientations of single domain <span class="hlt">magnetic</span> grains (diameter ≤ 1µm) are perpendicular to their long-axes. AMS results from samples having dominantly multi domain <span class="hlt">magnetic</span> particles are already controversial. The occurence of paramagnetic minerals such as biotite in rocks complicates the interpretation of AMS results. The physical origin of the AMS fabric in ignimbrites remains still enigmatic. The emplacement temperatures, lithification and welding degrees, and alteration occurred during cooling after emplacements operate to change the <span class="hlt">magnetic</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15253623','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15253623"><span>Control of magnetophoretic mobility by <span class="hlt">susceptibility</span>-modified solutions as evaluated by cell tracking velocimetry and continuous <span class="hlt">magnetic</span> sorting.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Moore, Lee R; Milliron, Sarah; Williams, P Stephen; Chalmers, Jeffrey J; Margel, Shlomo; Zborowski, Maciej</p> <p>2004-07-15</p> <p>With the analytical expression for the magnetophoretic mobility of an ideal, linearly polarizable sphere undergoing creeping motion in viscous medium, we have shown that both attractive and repulsive motions are possible in the <span class="hlt">magnetic</span> field. We have validated theoretical predictions using <span class="hlt">magnetic</span> monodisperse microspheres of 5.2-microm diameter and nonmagnetic polystyrene microspheres of 6.99-microm diameter suspended in solutions of paramagnetic ions. The microsphere magnetophoretic mobility was measured using a modified particle tracking velocimetry system, developed in-house and called a cell tracking velocimeter. The product of measured mobility and viscosity agrees well with the theoretical prediction, differing only by approximately 11%. Further, a 26% increase in resolution between <span class="hlt">magnetic</span> and nonmagnetic particle distributions was evaluated when paramagnetic ion carrier was used instead of water. Continuous particle sorting based on differences in magnetophoretic mobility was performed with another device developed by us, the quadrupole <span class="hlt">magnetic</span> flow sorter (QMS). In the QMS, the introduction of paramagnetic ions into the carrier was effective in suppressing nonspecific crossover (i.e., the transport of low-mobility particles into the <span class="hlt">magnetic</span> particle fraction) in particles and in biologically relevant red blood cells and thus showed promise as a means of increasing the purity of the <span class="hlt">magnetic</span> separation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3602381','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3602381"><span>MR <span class="hlt">Susceptibility</span> Imaging</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Duyn, Jeff</p> <p>2012-01-01</p> <p>This work reviews recent developments in the use of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> contrast for human MRI, with a focus on the study of brain anatomy. The increase in <span class="hlt">susceptibility</span> contrast with modern high field scanners has led to novel applications and insights into the sources and mechanism contributing to this contrast in brain tissues. Dedicated experiments have demonstrated that in most of healthy brain, iron and myelin dominate tissue <span class="hlt">susceptibility</span> variations, although their relative contribution varies substantially. Local variations in these compounds can affect both amplitude and frequency of the MRI signal. In white matter, the myelin sheath introduces an anisotropic <span class="hlt">susceptibility</span> that has distinct effects on the water compartments inside the axons, between the myelin sheath, and the axonal space, and renders their signals dependent on the angle between the axon and the <span class="hlt">magnetic</span> field. This offers opportunities to derive tissue properties specific to these cellular compartments. PMID:23273840</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27434134','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27434134"><span>Overview of quantitative <span class="hlt">susceptibility</span> mapping.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Deistung, Andreas; Schweser, Ferdinand; Reichenbach, Jürgen R</p> <p>2017-04-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> describes the magnetizability of a material to an applied <span class="hlt">magnetic</span> field and represents an important parameter in the field of MRI. With the recently introduced method of quantitative <span class="hlt">susceptibility</span> mapping (QSM) and its conceptual extension to <span class="hlt">susceptibility</span> tensor imaging (STI), the non-invasive assessment of this important physical quantity has become possible with MRI. Both methods solve the ill-posed inverse problem to determine the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> from local <span class="hlt">magnetic</span> fields. Whilst QSM allows the extraction of the spatial distribution of the bulk <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> from a single measurement, STI enables the quantification of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> anisotropy, but requires multiple measurements with different orientations of the object relative to the main static <span class="hlt">magnetic</span> field. In this review, we briefly recapitulate the fundamental theoretical foundation of QSM and STI, as well as computational strategies for the characterization of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> with MRI phase data. In the second part, we provide an overview of current methodological and clinical applications of QSM with a focus on brain imaging. Copyright © 2016 John Wiley & Sons, Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013BVol...75..753P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013BVol...75..753P"><span>Magma emplacement into the Lemptégy scoria cone (Chaîne Des Puys, France) explored with structural, anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, and Paleomagnetic data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petronis, M. S.; Delcamp, A.; van Wyk de Vries, B.</p> <p>2013-10-01</p> <p>The Lemptégy volcano is a small monogenetic scoria cone located in the Chaîne des Puys, Auvergne, France, which erupted about 32,000 years ago. A first edifice (Lemptégy 1) formed during a trachybasalt eruption as a group of satellite vents of the Puy de Gouttes scoria cone. A second trachyandesitic edifice (Lemptégy 2) formed soon after and completely covered Lemptégy 1 with an 80-m-high breached cone. Since 1946, the Lemptégy volcano has been quarried for scoria and today offers unprecedented three-dimensional exposure of the subvolcanic plumbing system. To map the internal flow architecture of the plumbing system and to study the subvolcanic deformation of Lemptégy 2, structural mapping, petrographic observations, anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS), rock <span class="hlt">magnetic</span>, and paleomagnetic data were collected. Field structural mapping and thin section study of tension gashes, Riedel shears, striations as well as ductile shear zones and bubbles allow the direction and sense of the magma flow to be determined. Twenty AMS sites were established in ten dikes (one to four sites in each dike) with 504 specimens analyzed and 479 specimens used to infer magma flow patterns. Structural data, the maximum <span class="hlt">susceptibility</span> axis ( K 1), and the imbrication of the <span class="hlt">magnetic</span> foliation ( K 1- K 2) planes indicate both upward and downward sense of flow, as well as flow toward and away from the central vent. Rock <span class="hlt">magnetic</span> experiments reveal that a cubic Fe-Ti oxide phase, likely low-Ti titanomagnetite, is the principal <span class="hlt">magnetic</span> phase carrying both the remanence and anisotropy. Paleomagnetic data from some sites yield statistically distinct, at the 95 % confidence level, remanence directions while at other sites the data are indistinguishable at the 95 % confidence level. The paleomagnetic results, observed steeply tilted scoria layers, internal unconformities, and faults show that as each dike was emplaced, it displaced earlier dikes evidencing subvolcanic deformation. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6828874','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6828874"><span>NMR determination of the orientation of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> tensor in cyanometmyoglobin: A new probe of steric tilt of bound ligand</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Emerson, S.D.; La Mar, G.N. )</p> <p>1990-02-13</p> <p>The experimentally determined paramagnetic dipolar shifts for noncoordinated amino acid side-chain protons in the heme pocket of sperm whale cyanometmyoglobin were used to determine in solution the orientation of the principal axes for the paramagnetic <span class="hlt">susceptibility</span> tensor relative to the heme iron molecular coordinates. The determination was made by a least-squares search for the unique Euler rotation angles which convert the geometric factors in the molecular (crystal) coordinates to ones that correctly predict each of 41 known dipolar shifts by using the <span class="hlt">magnetic</span> anisotropies computed previously. An excellent fit to experimental shifts was obtained, which also provided predictions that allowed subsequent new assignments to be made. The <span class="hlt">magnetic</span> axes are oriented so that the z axis is tipped {approximately}15{degree} from the heme normal toward the heme {delta}-meso-H and coincides approximately with the characterized FeCO tilt axis in the isostructural MbCO complex. Since the FeCO and FeCN units are isostructural, the authors propose that the dominant protein constraint that tips the <span class="hlt">magnetic</span> z axis from the heme normal is the tilt of the FeCN by steric interactions with the distal residues. It is shown that the proximal His ring nonlabile proton hyperfine shifts provide direct and exquisitely sensitive indicators of the degree of the z axis tilt that may serve as a valuable probe for characterizing variable steric interactions in the distal pocket of both point mutants and natural genetic variants of myoglobin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.2680H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.2680H"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> as a high-resolution climate proxy in lacustrine sediments of the Qaidam paleolake (NE Tibetan Plateau) throughout the Quaternary</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Herb, Christian; Appel, Erwin; Koutsodendris, Andreas; Voigt, Silke; Pross, Jörg; Zhang, Weilin; Fang, Xiaomin</p> <p>2014-05-01</p> <p><span class="hlt">Magnetic</span> proxies in lacustrine archives play an important role as they are acquirable in high resolution due to short measurement times. One premise for building a link between <span class="hlt">magnetic</span> properties and climate variation is to investigate what is controlling their changes. The <span class="hlt">magnetic</span> record of drill core SG-1 (940-m-long) in the Qaidam Basin, in particular <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (Ξ), is a good example for the value of <span class="hlt">magnetic</span> properties concerning climate change. SG-1 was obtained from the Chahansilatu sub-basin in the western, presently hyper-arid Qaidam Basin and contains late Pliocene-Quaternary lacustrine sediments. Potential humidity sources in that region during the past were primarily the Westerlies but also the East Asian monsoon. Time markers for depth-time transformation of drill core SG-1 were previously acquired by magnetostratigraphic and optical stimulated luminescence (OSL) dating, indicating a time span from 2.8 to 0.1 Ma. Relating the high-amplitude variation of the Ξ record to orbital forcing and applying extensive time series analysis, a more detailed depth to time transformation is achieved. To assess the climate sensitivity of Ξ, the Ξ record is compared with other <span class="hlt">magnetic</span> parameters and with palynological results. The pollen ratio Artemisia/Chenopodiaceae (A/C) shows a good anti-correlation with Ξ values, except of the interval around ~1.5 Ma. Thus, for core SG-1 high and low Ξ values predominantly document dryer and less dry conditions, respectively. Our observations reduce the possible mechanisms leading to the observed Ξ variation to two interfering scenarios: low-temperature oxidation (LTO) in the sedimentary source area and a change of the catchment area. As a bottom line of this study, the updated time frame of drill core SG-1 and the comparison of Ξ with other <span class="hlt">magnetic</span> properties and palynological results lead to a well-dated, high-resolution record of humidity fluctuations during the late Pliocene-Quaternary on the NE fringe</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SSCom.253...57Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SSCom.253...57Y"><span>The electronic properties, electronic heat capacity and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of monolayer boron nitride graphene-like structure in the presence of electron-phonon coupling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yarmohammadi, Mohsen</p> <p>2017-03-01</p> <p>In this work, we have studied the influences of electron-phonon (e-ph) coupling and chemical potential on the boron nitride graphene-like sheet. In particular, by starting the Green's function technique and Holstein model, the electronic density of states (DOS), electronic heat capacity (EHC) and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS) of this system have been investigated in the context of self-consistent second order perturbation theory which has been implemented to find the electronic self-energy. Our findings show that the band gap size decreases (increases) with e-ph coupling (chemical potential) parameters. The Schottky anomaly (crossover) decreases in EHC (MS) as soon as e-ph coupling increases. Also, the corresponding temperature with Schottky anomaly is considerably affected by e-ph coupling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920032042&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DSedimentary%2Brocks','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920032042&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DSedimentary%2Brocks"><span>Monte Carlo simulation of errors in the anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> - A second-rank symmetric tensor. [for grains in sedimentary and volcanic rocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lienert, Barry R.</p> <p>1991-01-01</p> <p>Monte Carlo perturbations of synthetic tensors to evaluate the Hext/Jelinek elliptical confidence regions for anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) eigenvectors are used. When the perturbations are 33 percent of the minimum anisotropy, both the shapes and probability densities of the resulting eigenvector distributions agree with the elliptical distributions predicted by the Hext/Jelinek equations. When the perturbation size is increased to 100 percent of the minimum eigenvalue difference, the major axis of the 95 percent confidence ellipse underestimates the observed eigenvector dispersion by about 10 deg. The observed distributions of the principal <span class="hlt">susceptibilities</span> (eigenvalues) are close to being normal, with standard errors that agree well with the calculated Hext/Jelinek errors. The Hext/Jelinek ellipses are also able to describe the AMS dispersions due to instrumental noise and provide reasonable limits for the AMS dispersions observed in two Hawaiian basaltic dikes. It is concluded that the Hext/Jelinek method provides a satisfactory description of the errors in AMS data and should be a standard part of any AMS data analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994JAP....75.7134K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994JAP....75.7134K"><span><span class="hlt">Magnetic</span> ordering in UCoNiSi2 and UCoCuSi2 studied by ac-<span class="hlt">susceptibility</span> and neutron-diffraction measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuznietz, Moshe; Pinto, Haim; Melamud, Mordechai</p> <p>1994-05-01</p> <p>Polycrystalline samples of intermediate solid solutions of the UM2Si2 compounds (M=Co,Ni,Cu), namely UCoNiSi2 and UCoCuSi2, were prepared and were found to have body-centered tetragonal ThCr2Si2-type crystallographic structure. In UCoNiSi2 ac <span class="hlt">susceptibility</span> indicates a single antiferromagnetic (AF) transition at TN=115±5 K, confirmed by neutron-diffraction observation of the AF-I structure down to 10 K (with uranium moments of 1.6±0.2μB, along the tetragonal c axis). In UCoCuSi2 ac <span class="hlt">susceptibility</span> indicates ferromagnetic transition at TC=107±5 K, and implies an AF transition at lower temperature, confirmed by the AF-I structure, observed in neutron diffraction below T0=95±5 K down to 10 K (with uranium moments of 1.6±0.1μB, along the c axis). The <span class="hlt">magnetic</span> properties are discussed in comparison with UM2X2 and U(M,M')2X2 materials (X=Si,Ge).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ADNDT.113..316S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ADNDT.113..316S"><span><span class="hlt">Magnetic</span>-dipole-to-electric-quadrupole cross-<span class="hlt">susceptibilities</span> for relativistic hydrogenlike atoms in some low-lying discrete energy eigenstates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stefańska, Patrycja</p> <p>2017-01-01</p> <p>In this paper we present tabulated data for <span class="hlt">magnetic</span>-dipole-to-electric-quadrupole cross-<span class="hlt">susceptibilities</span> (χ M 1 →E 2) for Dirac one-electron atoms with a pointlike, spinless and motionless nucleus of charge Ze. Numerical values of this <span class="hlt">susceptibility</span> for the hydrogen atom (Z = 1) and for hydrogenic ions with 2 ⩽ Z ⩽ 137 are computed from the general analytical formula, recently derived by us (Stefanska, 2016), valid for an arbitrary discrete energy eigenstate. In this work we provide 30 tables with the values of χ M 1 →E 2 for the ground state, and also for the first, the second and the third set of excited states (i.e.: 2s1/2, 2p1/2, 2p3/2, 3s1/2, 3p1/2, 3p3/2, 3d3/2, 3d5/2, 4s1/2, 4p1/2, 4p3/2, 4d3/2, 4d5/2, 4f5/2 and 4f7/2) of the relativistic hydrogenlike atoms. The value of the inverse of the fine-structure constant used in the calculations is α-1 = 137.035999139, and was taken from CODATA 2014.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5025436','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5025436"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> and feldspar zonations in the Peoria Loess and Roxana Silt of southwestern Illinois and eastern Missouri: Correlation tools and provenance indicators</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Grimley, D.A. . Dept. of Geology)</p> <p>1993-03-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> zonations within the Peoria Loess and Roxana Silt are useful for correlations across several counties in southwestern Illinois and eastern Missouri. The Roxana Silt and lower Peoria Loess (60--80 [times] 10[sup [minus]5] SI units) contain a greater concentration of primary magnetite in all silt fractions than the middle Peoria Loess (40--55 [times] 10[sup [minus]5] SI units). Similarly, feldspar contents (as determined from X-ray diffraction of micronized silts) are 30% to 40% higher in the high <span class="hlt">susceptibility</span> zones, while the bulk grain size distributions do not vary significantly. Therefore, the origin of these mineralogical zones is best explained by the changing proportion of silt derived from igneous and metamorphic rocks as compared with silt derived from sedimentary rocks. During deposition of the Roxana Silt and lower Peoria Loess, an ice margin in Upper Michigan, Wisconsin, Minnesota, or the Canadian Shield, would be responsible for the erosion of a greater proportion of shield lithologies. During the Wisconsinan glacial maximum, the erosion of Paleozoic sedimentary rocks by the advance of the Lake Michigan Lobe diluted the contribution of shield lithologies to the middle Peoria Loess. Higher magnetite and feldspar contents, present in the upper Peoria Loess when relatively unweathered, coincide with a receding ice margin during the latest Wisconsinan.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27939794','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27939794"><span>Studying cyto and myeloarchitecture of the human cortex at ultra-high field with quantitative imaging: R1, R2(*) and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marques, José P; Khabipova, Diana; Gruetter, Rolf</p> <p>2017-02-15</p> <p>In this manuscript, the use of quantitative imaging at ultra-high field is evaluated as a mean to study cyto and myelo-architecture of the cortex. The quantitative contrasts used are the longitudinal relaxation rate (R1), apparent transverse relaxation rate (R2(*)) and quantitative <span class="hlt">susceptibility</span> mapping (QSM). The quantitative contrasts were computed using high resolution in-vivo (0.65mm isotropic) brain data acquired at 7T. The performance of the different quantitative approaches was evaluated by visualizing the contrast between known highly myelinated primary sensory cortex regions and the neighbouring cortex. The transition from the inner layers to the outer layers (from white matter to the pial surface) of the human cortex, which is known to have varying cyto- and myelo architecture, was evaluated. The across cortex and through depth behaviour observed for the different quantitative maps was in good agreement between the different subjects, clearly allowing the differentiation between different Brodmann regions, suggesting these features could be used for individual cortical brain parcellation. While both R1 and R2(*) maps decrease monotonically from the white matter to the pial surface due to the decrease of myelin and iron between these regions, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> maps have a more complex behaviour reflecting its opposing sensitivity to myelin and iron concentration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JOpt...18e5001W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JOpt...18e5001W"><span><span class="hlt">Generalised</span> Hermite-Gaussian beams and mode transformations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Yi; Chen, Yujie; Zhang, Yanfeng; Chen, Hui; Yu, Siyuan</p> <p>2016-05-01</p> <p><span class="hlt">Generalised</span> Hermite-Gaussian modes (gHG modes), an extended notion of Hermite-Gaussian modes (HG modes), are formed by the summation of normal HG modes with a characteristic function α, which can be used to unite conventional HG modes and Laguerre-Gaussian modes (LG modes). An infinite number of normalised orthogonal modes can thus be obtained by modulation of the function α. The gHG mode notion provides a useful tool in analysis of the deformation and transformation phenomena occurring in propagation of HG and LG modes with astigmatic perturbation.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...08..144T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...08..144T"><span><span class="hlt">Generalised</span> boundary terms for higher derivative theories of gravity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Teimouri, Ali; Talaganis, Spyridon; Edholm, James; Mazumdar, Anupam</p> <p>2016-08-01</p> <p>In this paper we wish to find the corresponding Gibbons-Hawking-York term for the most general quadratic in curvature gravity by using Coframe slicing within the Arnowitt-Deser-Misner (ADM) decomposition of spacetime in four dimensions. In order to make sure that the higher derivative gravity is ghost and tachyon free at a perturbative level, one requires infinite covariant derivatives, which yields a <span class="hlt">generalised</span> covariant infinite derivative theory of gravity. We will be exploring the boundary term for such a covariant infinite derivative theory of gravity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhLB..756..400B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhLB..756..400B"><span>Spacetimes with vector distortion: Inflation from <span class="hlt">generalised</span> Weyl geometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beltrán Jiménez, Jose; Koivisto, Tomi S.</p> <p>2016-05-01</p> <p>Spacetime with general linear vector distortion is introduced. Thus, the torsion and the nonmetricity of the affine connection are assumed to be proportional to a vector field (and not its derivatives). The resulting two-parameter family of non-Riemannian geometries <span class="hlt">generalises</span> the conformal Weyl geometry and some other interesting special cases. Taking into account the leading nonlinear correction to the Einstein-Hilbert action results uniquely in the one-parameter extension of the Starobinsky inflation known as the alpha-attractor. The most general quadratic curvature action introduces, in addition to the canonical vector kinetic term, novel ghost-free vector-tensor interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995JSSCh.114..311N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995JSSCh.114..311N"><span>Manganese(II,III) Oxyborate, Mn 2OBO 3: A Distorted Homometallic Warwickite—Synthesis, Crystal Structure, Band Calculations, and <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Norrestam, R.; Kritikos, M.; Sjödin, A.</p> <p>1995-02-01</p> <p>The manganese(II,III) oxyborate with the composition Mn2OBO3 has been synthesized by high-temperature techniques. X-ray studies show that crystals of the specimen, grown with borax as flux, are monoclinic, with space group P21/n, = 9.2866(7), b = 9.5333(10), c = 3.2438(3) Å, and β = 90.757(7)°. A model of the crystal structure has been refined with the 2064 most significant (l ≥ 5 · σ1) X-ray reflections with sin(θ)/λ ≤ 1.08 Å-1 to R = 0.40. The structure of Mn2OBO3 can be considered to be a distorted modification of the orthorhombic warwickite structure. The distortions, apparently caused by Jahn-Teller effects induced by the Mn3+ ions, remove the mirror symmetry of the parent undistorted warwickite. As a consequence, the space group symmetry is lowered from Pnam to one of its subgroups, P21/n. The structural results as well as the measured <span class="hlt">magnetic</span> <span class="hlt">susceptibilities</span> indicate high-spin manganese ions. The <span class="hlt">magnetic</span> <span class="hlt">susceptibilities</span> in the temperature region 110-300 K follow the Curie-Weiss law. The Weiss constant of -132(1) K indicates an antiferromagnetic ordering at low temperature. The bond distances and calculated bond valence sums indicate that the trivalent manganese ions are located in the two inner columns of the four-octahedra-wide walls. This metal charge distribution is supported by extended Hückel band calculations on some homometallic warwickites. The difference in metal coordination around one of the borate oxygen atoms is reflected by a significant deviation of the borate group geometry from the ideal trigonal symmetry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007M%26PS...42..839S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007M%26PS...42..839S"><span>Characterization of the log lithology of cores LB-07A and LB-08A of the Bosumtwi impact structure by using the anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schell, Christina; Schleifer, Norbert; Elbra, Tiiu</p> <p></p> <p>Petrophysical data are commonly used for the discrimination of different lithologies, as the variation in mineralogy, texture, and porosity is accompanied by varying physical properties. A special field of investigation is the analysis of the directional dependence (anisotropy) of the petrophysical properties, which can provide further information on the characteristics of the lithologies, due to the fact that this parameter is different in the various rock-forming and rockchanging processes, e.g., deformation or sedimentation. To characterize the rocks in drill cores LB-07A and LB-08A, which were drilled into the deep crater moat and central uplift of the Bosumtwi impact structure, Ghana, samples were taken for the study of petrophysical properties. In the present work the <span class="hlt">magnetic</span> properties of these samples were determined in the laboratory. The results are discussed in relation to the various lithologies represented by this sample suite. The shape and degree of <span class="hlt">magnetic</span> anisotropy, in combination with the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, proved useful in distinguishing between the different lithologies present in the drill cores (polymict lithic breccia, suevite, shale component, and meta-graywacke). It was possible to correlate layers of high (shale component), ntermediate (graywacke, polymict lithic breccia), and low (suevite) anisotropy degree with the lithostratigraphic sequences determined for cores LB-07A and LB-08A. The shape of the anisotropy showed that foliation is most dominant within the shale component, whereas lineation is more pronounced in the meta-graywacke and polymict lithic breccia. An overall increase of the anisotropy degree was observed from core LB-07A towards core LB-08A. Thus <span class="hlt">magnetic</span> anisotropy data provide a useful contribution towards an improved petrophysical characterization of the lithostratigraphic sequences in drillcores from the Bosumtwi impact structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRB..118.1984G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRB..118.1984G"><span>Late-stage magma flow in a shallow felsic reservoir: Merging the anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> record with numerical simulations in La Gloria Pluton, central Chile</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>GutiéRrez, F.; PayacáN, I.; Gelman, S. E.; Bachmann, O.; Parada, M. A.</p> <p>2013-05-01</p> <p>La Gloria Pluton is a 10 Myr old epizonal intrusion located in the southern Andes. We present anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> data that indicate a <span class="hlt">magnetic</span> fabric that is mainly oblate. We find that lineations are weak and have a N-NW trend with a nearly horizontal dip, while foliations are more pronounced, have NW trends, and have dips that vary from vertical at the walls of the intrusion to horizontal at the center and under the roof of the chamber. To interpret these magmatic fabrics, we developed a time-dependent 2-D magmatic fluid dynamic numerical simulation. Our model is calibrated with MELTS and accounts for the coupled processes of cooling, crystallization, and degassing of a magma chamber. Simulations indicate that the resulting convective flow pattern in the crystallizing reservoir is consistent with the <span class="hlt">magnetic</span> fabric, which is largely produced in the shear zone between the convecting liquid-dominated core and the growing solidification fronts adjacent to the walls. The <span class="hlt">magnetic</span> fabric records the last increment of strain induced by convective magmatic flow in the cooling reservoir during crystallization at the rheological magma locking point along solidification fronts. Despite the small size of the pluton, the core of the chamber remains thermally insulated from the colder host rocks, surviving up to 20 kyr above the solidus, which allows enough time for the extraction of residual leucogranitic melt and partial late magmatic reactive recrystallization. The results of the simulations are also consistent with the previously determined compositional and mineralogical zonation patterns in the pluton.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://labtestsonline.org/understanding/analytes/susceptibility/tab/glance','NIH-MEDLINEPLUS'); return false;" href="https://labtestsonline.org/understanding/analytes/susceptibility/tab/glance"><span><span class="hlt">Susceptibility</span> Testing</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Also known as: Sensitivity Testing; Drug Resistance Testing; Culture and Sensitivity; C & S; Antimicrobial <span class="hlt">Susceptibility</span> Formal name: Bacterial and Fungal <span class="hlt">Susceptibility</span> Testing Related tests: Urine Culture ; Blood Culture ; Bacterial Wound Culture ; AFB Testing ; MRSA ; ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1611863I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1611863I"><span>Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> (AMS) of Carbonate Rocks as a Proxy for the Strain Field near the Dead Sea Transform in Northern Israel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Issachar, Ran; Levi, Tsafrir; Weinberger, Ram; Marco, Shmuel</p> <p>2014-05-01</p> <p>To exploit the potential of anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) axes (k1, k2, k3) and magnitudes as a tool to estimate the strain field around major faults, the AMS of calcite-bearing diamagnetic rocks that crop out next to the Dead Sea Transform (DST) were measured. The low-field bulk-<span class="hlt">susceptibility</span> of Bar-Kokhba limestone formation is -10.67±1.69 [µSI], very close to the value of a single calcite crystal. Thermomagnetic curves show temperature independent and reversible behavior. Chemical composition analysis indicates minor amounts of Fe contents <300 ppm. Results of XRD diffraction and petrofabric study of thin-sections and SEM images indicate that the Bar-Kokhba rocks are calcite mono-mineralic rocks. The <span class="hlt">magnetic</span> fabrics are solely controlled by the alignment of c-axes of almost pure calcite crystals and help to assess the direction of the maximum shortening prevailing post-deposition and during the tectonic evolution of the DST. In one studied site, high Fe contents <6000 ppm were found, which are associated with young morphological processes of chemical alteration. In this site, thermomagnetic curves indicate temperature dependency and irreversibility. IRM curves show saturation around 200 mT, evidence of ferro/ferimagnetic minerals. AARM measurements reveal isotropic fabric which suggesting that the ferro/ferimagnetic minerals are contributing no anisotropy to the AMS. The AMS of the diamagnetic fabric is masked by a paramagnetic fabric of Fe-bearing minerals. Using liner correlation between Fe content and bulk <span class="hlt">susceptibility</span> we applied a novel tensor subtraction method and successfully isolated the diamagnetic fabric from the total AMS. The paramagnetic fabric has characteristics of sedimentary fabrics, while that of the diamagnetic fabric has tectonic characteristics. The isolation process indicates that the AMS of carbonate rocks is mostly controlled by the diamagnetic phase, where the Fe content is below 500 ppm. Differences in the degree of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5235383','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5235383"><span><span class="hlt">Generalising</span> Ward’s Method for Use with Manhattan Distances</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Strauss, Trudie; von Maltitz, Michael Johan</p> <p>2017-01-01</p> <p>The claim that Ward’s linkage algorithm in hierarchical clustering is limited to use with Euclidean distances is investigated. In this paper, Ward’s clustering algorithm is <span class="hlt">generalised</span> to use with l1 norm or Manhattan distances. We argue that the <span class="hlt">generalisation</span> of Ward’s linkage method to incorporate Manhattan distances is theoretically sound and provide an example of where this method outperforms the method using Euclidean distances. As an application, we perform statistical analyses on languages using methods normally applied to biology and genetic classification. We aim to quantify differences in character traits between languages and use a statistical language signature based on relative bi-gram (sequence of two letters) frequencies to calculate a distance matrix between 32 Indo-European languages. We then use Ward’s method of hierarchical clustering to classify the languages, using the Euclidean distance and the Manhattan distance. Results obtained from using the different distance metrics are compared to show that the Ward’s algorithm characteristic of minimising intra-cluster variation and maximising inter-cluster variation is not violated when using the Manhattan metric. PMID:28085891</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24000512','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24000512"><span>Postcoital <span class="hlt">generalised</span> pruritus as a first symptom of polycythaemia vera.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Patidar, O P; Patidar, Rekha; Patidar, R P</p> <p>2013-01-01</p> <p>Ploycythaemia vera (PV) is most common of chronic myeloproliferative disorder that involves the multipotent haemaotopoietic progenitor cells. PV has indolent course and recognised either by incidental discovery of high haemoglobin or haemtocrit. PV may present with aquagenic pruritus (AP) for years together without any other sign and symptoms. So advice of simple complete bood count as a routine in every case of pruritus can be helpful to diagnose it timely thereby dreaded complications of PV, related to hyperviscosity of blood like thrombosis both arterial and venous can be managed antecedently. A 50-year-old male doctor diagnosed as a case of PV presented to us with postcoital <span class="hlt">generalised</span> pruritus (PCP) as a first, rarest symptoms and he remained undiagnosed for 10 years till he developed other features of PV like aquagenic pruritus, headache, red congestion in eyes and erythromelalgia symptoms complex erythema, burning pain and warmness of lower extremities. Then he was investigated and was found to have high haemoglobin or haemtocrit, JAK 2 genetic mutation changes were present, bone marrow biopsy and other biochemical investigations confirmed the diagnosis of PV. Initially he was managed with repeated phlebotomy to bring down high haemtocrit value in acceptable range (approximately 45%). Simultaneously he was put on hydroxyurea 500 mg twice daily doses. Since then his symptoms improved and monthly blood count was done to monitor the haemtocrit. So advice of simple blood count is highly informative in every case of <span class="hlt">generalised</span> pruritus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28085891','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28085891"><span><span class="hlt">Generalising</span> Ward's Method for Use with Manhattan Distances.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Strauss, Trudie; von Maltitz, Michael Johan</p> <p>2017-01-01</p> <p>The claim that Ward's linkage algorithm in hierarchical clustering is limited to use with Euclidean distances is investigated. In this paper, Ward's clustering algorithm is <span class="hlt">generalised</span> to use with l1 norm or Manhattan distances. We argue that the <span class="hlt">generalisation</span> of Ward's linkage method to incorporate Manhattan distances is theoretically sound and provide an example of where this method outperforms the method using Euclidean distances. As an application, we perform statistical analyses on languages using methods normally applied to biology and genetic classification. We aim to quantify differences in character traits between languages and use a statistical language signature based on relative bi-gram (sequence of two letters) frequencies to calculate a distance matrix between 32 Indo-European languages. We then use Ward's method of hierarchical clustering to classify the languages, using the Euclidean distance and the Manhattan distance. Results obtained from using the different distance metrics are compared to show that the Ward's algorithm characteristic of minimising intra-cluster variation and maximising inter-cluster variation is not violated when using the Manhattan metric.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AIPC..756..333N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AIPC..756..333N"><span>Mesonic states in the <span class="hlt">generalised</span> Nambu-Jona-Lasinio theories</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nefediev, A. V.; Ribeiro, J. E. F. T.</p> <p>2005-04-01</p> <p>For any Nambu-Jona-Lasinio model of QCD with arbitrary nonlocal, instantaneous, quark current-current confining kernels, we use a <span class="hlt">generalised</span> Bogoliubov technique to go beyond BCS level (in the large-NC limit) so as to explicitly build quark-antiquark compound operators for creating/annihilating mesons. In the Hamiltonian approach, the mesonic bound-state equations appear (from the <span class="hlt">generalised</span> Bogoliubov transformation) as mass-gap-like equations which, in turn, ensure the absence, in the Hamiltonian, of mesonic Bogoliubov anomalous terms. We go further to demonstrate the one-to-one correspondence between Hamiltonian and Bethe-Salpeter approaches to non-local NJL-type models for QCD and give the corresponding "dictionary" necessary to "translate" the amplitudes built using the graphical Feynman rules to the terms of the Hamiltonian, and vice versa. We comment on the problem of multiple vacua existence in such type of models and argue that mesonic states in the theory should be prescribed to have an extra index — the index of the replica in which they are created. Then the completely diagonalised Hamiltonian should contain a sum over this new index. The method is proved to be general and valid for any instantaneous quark kernel.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70022251','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70022251"><span>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> as a tool for recognizing core deformation: reevaluation of the paleomagnetic record of Pleistocene sediments from drill hole OL-92, Owens Lake, California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Rosenbaum, Joseph; Reynolds, Richard T.; Smoot, Joseph; Meyer, Robert</p> <p>2000-01-01</p> <p>At Owens Lake, California, paleomagnetic data document the Matuyama/Brunhes polarity boundary near the bottom of a 323-m core (OL-92) and display numerous directional fluctuations throughout the Brunhes chron. Many of the intervals of high directional dispersion were previously interpreted to record <span class="hlt">magnetic</span> excursions. For the upper ~120 m, these interpretations were tested using the anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS), which typically defines a subhorizontal planar fabric for sediments deposited in quiet water. AMS data from intervals of deformed core, determined from detailed analysis of sedimentary structures, were compared to a reference AMS fabric derived from undisturbed sediment. This comparison shows that changes in the AMS fabric provide a means of screening core samples for deformation and the associated paleomagnetic record for the adverse effects of distortion. For that portion of core OL-92 studied here (about the upper 120 m), the combined analyses of sedimentary structures and AMS data demonstrate that most of the paleomagnetic features, previously interpreted as geomagnetic excursions, are likely the result of core deformation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15285674','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15285674"><span>Investigation of the electronic and structural properties of potassium hexaboride, KB6, by transport, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, EPR, and NMR measurements, temperature-dependent crystal structure determination, and electronic band structure calculations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ammar, A; Ménétrier, M; Villesuzanne, A; Matar, S; Chevalier, B; Etourneau, J; Villeneuve, G; Rodríguez-Carvajal, J; Koo, H-J; Smirnov, A I; Whangbo, M-H</p> <p>2004-08-09</p> <p>The electronic and structural properties of potassium hexaboride, KB(6), were examined by transport, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, EPR, and NMR measurements, temperature-dependent crystal structure determination, and electronic band structure calculations. The valence bands of KB(6) are partially empty, but the electrical resistivity of KB(6) reveals that it is not a normal metal. The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> as well as EPR and NMR measurements show the presence of localized electrons in KB(6). The EPR spectra of KB(6) have two peaks, a broad ( approximately 320 G) and a narrow (less than approximately 27 G) line width, and the temperature-dependence of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of KB(6) exhibits a strong hysteresis below 70 K. The temperature-dependent crystal structure determination of KB(6) shows the occurrence of an unusual variation in the unit cell parameter hence supporting that the hysteresis of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> is a bulk phenomenon. The line width DeltaH(pp) of the broad EPR signal is independent of temperature and EPR frequency. This finding indicates that the line broadening results from the dipole-dipole interaction, and the spins responsible for the broad EPR peak has the average distance of approximately 1.0 nm. To explain these apparently puzzling properties, we examined a probable mechanism of electron localization in KB(6) and its implications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6642467','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6642467"><span>Electrophoretic and electro-optical studies on the conformation and <span class="hlt">susceptibility</span> to psoralen crosslinking of <span class="hlt">magnetically</span> oriented DNA</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Roots, R.J.; Kraft, G.H.; Farinato, R.S.; Tenforde, T.S.</p> <p>1982-08-01</p> <p>Gel electrophoresis and electro-optical birefringence measurements were performed on the replicative form of bacteriophage phi X-174 DNA subjected to orientation in a homogeneous stationary <span class="hlt">magnetic</span> field. The conformation of this superhelical double-stranded form of DNA, and its sensitivity to intercalation and crosslinking by a psoralen derivative, were found to be unaffected by a 1 h exposure to a 2.15 Tesla field. In addition, no alteration was detected in the infectivity of the exposed phi X-174 DNA in E. coli bacterial hosts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27120169','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27120169"><span><span class="hlt">Susceptibility</span> tensor imaging (STI) of the brain.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Wei; Liu, Chunlei; Duong, Timothy Q; van Zijl, Peter C M; Li, Xu</p> <p>2017-04-01</p> <p><span class="hlt">Susceptibility</span> tensor imaging (STI) is a recently developed MRI technique that allows quantitative determination of orientation-independent <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> parameters from the dependence of gradient echo signal phase on the orientation of biological tissues with respect to the main <span class="hlt">magnetic</span> field. By modeling the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of each voxel as a symmetric rank-2 tensor, individual <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> tensor elements as well as the mean <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> anisotropy can be determined for brain tissues that would still show orientation dependence after conventional scalar-based quantitative <span class="hlt">susceptibility</span> mapping to remove such dependence. Similar to diffusion tensor imaging, STI allows mapping of brain white matter fiber orientations and reconstruction of 3D white matter pathways using the principal eigenvectors of the <span class="hlt">susceptibility</span> tensor. In contrast to diffusion anisotropy, the main determinant factor of the <span class="hlt">susceptibility</span> anisotropy in brain white matter is myelin. Another unique feature of the <span class="hlt">susceptibility</span> anisotropy of white matter is its sensitivity to gadolinium-based contrast agents. Mechanistically, MRI-observed <span class="hlt">susceptibility</span> anisotropy is mainly attributed to the highly ordered lipid molecules in the myelin sheath. STI provides a consistent interpretation of the dependence of phase and <span class="hlt">susceptibility</span> on orientation at multiple scales. This article reviews the key experimental findings and physical theories that led to the development of STI, its practical implementations, and its applications for brain research. Copyright © 2016 John Wiley & Sons, Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20013390','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20013390"><span>Characterization of magnetite in silico-aluminous fly ash by SEM, TEM, XRD, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, and Moessbauer spectroscopy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gomes, S.; Francois, M.; Abdelmoula, M.; Refait, P.; Pellissier, C.; Evrard, O.</p> <p>1999-11-01</p> <p>Spinel magnetite contained in a silico-aluminous fly ash (originating from la Maxe's power plant, near Metz in the east of France) issued from bituminous coal combustion has been studied by scanning and transmission electron microscopy linked with energy dispersive spectroscopy. X-ray diffraction, <span class="hlt">susceptibility</span> measurements, and Moessbauer spectroscopy. The results show that in this magnetite Mg is strongly substituted for Fe and the chemical formula is closer to MgFe{sub 2}O{sub 4} than Fe{sub 3}O{sub 4}. Magnetite also contains Mn, Ca, and Si elements, but at a lower proportion. The results are compatible with the chemical formula Fe{sub 2.08}Mg{sub 0.75}Mn{sub 0.11}Ca{sub 0.04}Si{sub 0.02}O{sub 4} and crystallochemical formula [Fe{sup 2{minus}}{sub 0.92}Ca{sup 2+}{sub 0.06}Si{sup 4+}{sub 0.02}]{sup tetra}[Fe{sup 3+}Fe{sup 2+}{sub 0.16}Mg{sup 2+}{sub 0.73}Mn{sup 2+}{sub 0.11}]{sup octa}O{sub 4}, showing the cation distribution on octahedral and tetrahedral sites of the spinel structure. The reason Mg element is not incorporated in soluble surface salt and in glass composition of the silico-aluminous fly ashes is now understood.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21702553','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21702553"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> of alkali-tetracyanoquinodimethane salts and extended Hubbard models with bond order and charge density wave phases.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kumar, Manoranjan; Topham, Benjamin J; Yu, RuiHui; Ha, Quoc Binh Dang; Soos, Zoltán G</p> <p>2011-06-21</p> <p>The molar spin <span class="hlt">susceptibilities</span> χ(T) of Na-tetracyanoquinodimethane (TCNQ), K-TCNQ, and Rb-TCNQ(II) are fit quantitatively to 450 K in terms of half-filled bands of three one-dimensional Hubbard models with extended interactions using exact results for finite systems. All three models have bond order wave (BOW) and charge density wave (CDW) phases with boundary V = V(c)(U) for nearest-neighbor interaction V and on-site repulsion U. At high T, all three salts have regular stacks of TCNQ(-) anion radicals. The χ(T) fits place Na and K in the CDW phase and Rb(II) in the BOW phase with V ≈ V(c). The Na and K salts have dimerized stacks at T < T(d) while Rb(II) has regular stacks at 100 K. The χ(T) analysis extends to dimerized stacks and to dimerization fluctuations in Rb(II). The three models yield consistent values of U, V, and transfer integrals t for closely related TCNQ(-) stacks. Model parameters based on χ(T) are smaller than those from optical data that in turn are considerably reduced by electronic polarization from quantum chemical calculation of U, V, and t of adjacent TCNQ(-) ions. The χ(T) analysis shows that fully relaxed states have reduced model parameters compared to optical or vibration spectra of dimerized or regular TCNQ(-) stacks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22305958','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22305958"><span>The ac-<span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and dielectric response of complex spin ordering processes in Mn₃O₄</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Thota, Subhash E-mail: wilfrid.prellier@ensicaen.fr; Singh, Kiran; Simon, Ch.; Prellier, Wilfrid E-mail: wilfrid.prellier@ensicaen.fr; Nayak, Sanjib; Kumar, Jitendra</p> <p>2014-09-14</p> <p>We report a meticulous study of the ac-<span class="hlt">magnetization</span> dynamics (χ{sub ac}(T)), relative dielectric permittivity ε{sub r}(T), and magneto-dielectric (Δε{sub r}/ε{sub r}(H)) response of various complex <span class="hlt">magnetic</span> transitions that occur below the ferrimagnetic Néel temperature T{sub N} of Mn₃O₄. Besides the known sequence of transitions at T{sub N}~42.75 K, T₁~39 K, and T₂~34 K, the existence of a new anomaly reported recently at 38 K (T*) has been successfully probed by χ{sub ac}(T) and ε{sub r}(T) measurements. The effect of external dc-bias fields (H{sub DC}) and driving frequency (f) on the above mentioned transitions has been investigated in consonance with the ε{sub r}(T) and Δε{sub r}/ε{sub r}(T,H) results. For the first time, we observed a clear hysteresis of about 5.15 K in the zero-field ε{sub r}(T) across the incommensurate-to-commensurate transition T₂~34 K, which provides evidence to the first-order nature of this transition. The Arrott plot (H/M vs. M²}) criterion has been used to distinguish the nature of all the sequential transitions that take place below T{sub N}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21039595','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21039595"><span><span class="hlt">Susceptibility</span> Contrast <span class="hlt">Magnetic</span> Resonance Imaging Determination of Fractional Tumor Blood Volume: A Noninvasive Imaging Biomarker of Response to the Vascular Disrupting Agent ZD6126</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Robinson, Simon P. Howe, Franklyn A.; Griffiths, John R.; Ryan, Anderson J.; Waterton, John C.</p> <p>2007-11-01</p> <p>Purpose: To assess tumor fractional blood volume ({xi}), determined in vivo by <span class="hlt">susceptibility</span> contrast <span class="hlt">magnetic</span> resonance imaging (MRI) as a noninvasive imaging biomarker of tumor response to the vascular disrupting agent ZD6126. Methods and Materials: The transverse MRI relaxation rate R{sub 2}* of rat GH3 prolactinomas was quantified prior to and following injection of 2.5 mgFe/kg feruglose, an ultrasmall superparamagnetic iron oxide intravascular contrast agent, and {xi} (%) was determined from the change in R{sub 2}*. The rats were then treated with either saline or 50 mg/kg ZD6126, and {xi} measured again 24 hours later. Following posttreatment MRI, Hoechst 33342 (15 mg/kg) was administered to the rats and histological correlates from composite images of tumor perfusion and necrosis sought. Results: Irrespective of treatment, tumor volume significantly increased over 24 hours. Saline-treated tumors showed no statistically significant change in {xi}, whereas a significant (p = 0.002) 70% reduction in {xi} of the ZD6126-treated cohort was determined. Hoechst 33342 uptake was associated with viable tumor tissue and was significantly (p = 0.004) reduced and restricted to the rim of the ZD6126-treated tumors. A significant positive correlation between posttreatment {xi} and Hoechst 33342 uptake was obtained (r = 0.83, p = 0.002), providing validation of the MRI-derived measurements of fractional tumor blood volume. Conclusions: These data clearly highlight the potential of <span class="hlt">susceptibility</span> contrast MRI with ultrasmall superparamagnetic iron oxide contrast agents to provide quantitative imaging biomarkers of fractional tumor blood volume at high spatial resolution to assess tumor vascular status and response to vascular disrupting agents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3948055','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3948055"><span><span class="hlt">Generalised</span> weakness in a young patient: a cause for concern?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Saenz-Abad, Daniel; Rivero-Sanz, Elena; Lahoz-Perez, Maria del Carmen; Martinez-Diez, Maria</p> <p>2014-01-01</p> <p>Muscular weakness in young patients is usually due to mild, self-limiting causes. Nonetheless, it is important to remember other, more serious aetiologies which can cause this clinical picture. Thyrotoxic hypokalaemic periodic paralysis (THPP) is a rare disease in Europe and the USA, with fatal cardiovascular and respiratory complications. It is characterised by recurrent episodes of <span class="hlt">generalised</span> muscular weakness, especially in the legs, with an associated hypokalaemia and hyperthyroidism. Diagnosis is based on clinical history, laboratory tests and an ECG. Early treatment focused on cautious correction blood potassium and non-cardiac selective β-blockers. Additionally, it is imperative to normalise thyroid function to prevent relapses. We present a young, healthy man to the emergency department with episodes of intermittent leg weakness. The history and the ECG findings allowed for the diagnosis of THPP to be reached with early treatment causing remission. PMID:24591389</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016FBS....57..729M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016FBS....57..729M"><span>From Bethe-Salpeter Wave functions to <span class="hlt">Generalised</span> Parton Distributions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mezrag, C.; Moutarde, H.; Rodríguez-Quintero, J.</p> <p>2016-09-01</p> <p>We review recent works on the modelling of <span class="hlt">generalised</span> parton distributions within the Dyson-Schwinger formalism. We highlight how covariant computations, using the impulse approximation, allows one to fulfil most of the theoretical constraints of the GPDs. Specific attention is brought to chiral properties and especially the so-called soft pion theorem, and its link with the Axial-Vector Ward-Takahashi identity. The limitation of the impulse approximation are also explained. Beyond impulse approximation computations are reviewed in the forward case. Finally, we stress the advantages of the overlap of lightcone wave functions, and possible ways to construct covariant GPD models within this framework, in a two-body approximation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21215612','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21215612"><span><span class="hlt">Generalised</span> additive modelling approach to the fermentation process of glutamate.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Chun-Bo; Li, Yun; Pan, Feng; Shi, Zhong-Ping</p> <p>2011-03-01</p> <p>In this work, <span class="hlt">generalised</span> additive models (GAMs) were used for the first time to model the fermentation of glutamate (Glu). It was found that three fermentation parameters fermentation time (T), dissolved oxygen (DO) and oxygen uptake rate (OUR) could capture 97% variance of the production of Glu during the fermentation process through a GAM model calibrated using online data from 15 fermentation experiments. This model was applied to investigate the individual and combined effects of T, DO and OUR on the production of Glu. The conditions to optimize the fermentation process were proposed based on the simulation study from this model. Results suggested that the production of Glu can reach a high level by controlling concentration levels of DO and OUR to the proposed optimization conditions during the fermentation process. The GAM approach therefore provides an alternative way to model and optimize the fermentation process of Glu.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ZNatA..72..207C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ZNatA..72..207C"><span>Resistance Distances and Kirchhoff Index in <span class="hlt">Generalised</span> Join Graphs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Haiyan</p> <p>2017-03-01</p> <p>The resistance distance between any two vertices of a connected graph is defined as the effective resistance between them in the electrical network constructed from the graph by replacing each edge with a unit resistor. The Kirchhoff index of a graph is defined as the sum of all the resistance distances between any pair of vertices of the graph. Let G=H[G1, G2, …, Gk ] be the <span class="hlt">generalised</span> join graph of G1, G2, …, Gk determined by H. In this paper, we first give formulae for resistance distances and Kirchhoff index of G in terms of parameters of {G'_i}s and H. Then, we show that computing resistance distances and Kirchhoff index of G can be decomposed into simpler ones. Finally, we obtain explicit formulae for resistance distances and Kirchhoff index of G when {G'_i}s and H take some special graphs, such as the complete graph, the path, and the cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EJPh...37b5401B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EJPh...37b5401B"><span>Effects of the <span class="hlt">generalised</span> uncertainty principle on quantum tunnelling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blado, Gardo; Prescott, Trevor; Jennings, James; Ceyanes, Joshuah; Sepulveda, Rafael</p> <p>2016-03-01</p> <p>In a previous paper (Blado et al 2014 Eur. J. Phys. 35 065011), we showed that quantum gravity effects can be discussed with only a background in non-relativistic quantum mechanics at the undergraduate level by looking at the effect of the <span class="hlt">generalised</span> uncertainty principle (GUP) on the finite and infinite square wells. In this paper, we derive the GUP corrections to the tunnelling probability of simple quantum mechanical systems which are accessible to undergraduates (alpha decay, simple models of quantum cosmogenesis and gravitational tunnelling radiation) and which employ the WKB approximation, a topic discussed in undergraduate quantum mechanics classes. It is shown that the GUP correction increases the tunnelling probability in each of the examples discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ZNatA..71..331C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ZNatA..71..331C"><span>Spanning Trees of the <span class="hlt">Generalised</span> Union Jack Lattice</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Lingyun; Yan, Weigen</p> <p>2016-04-01</p> <p>The Union Jack lattice UJL(n, m) with toroidal boundary condition can be obtained from an n×m square lattice with toroidal boundary condition by inserting a new vertex vf to each face f and adding four edges (vf, ui(f)), where u1(f), u2(f), u3(f), and u4(f) are four vertices on the boundary of f. The Union Jack lattice has been studied extensively by statistical physicists. In this article, we consider the problem of enumeration of spanning trees of the so-called <span class="hlt">generalised</span> Union Jack lattice UDn, which is obtained from the Aztec diamond ADnt of order n with toroidal boundary condition by inserting a new vertex vf to each face f and adding four edges (vf, ui(f)), where u1(f), u2(f), u3(f) and u4(f) are four vertices on the boundary of f.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016npjSL...116012C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016npjSL...116012C"><span>Optimising, <span class="hlt">generalising</span> and integrating educational practice using neuroscience</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Colvin, Robert</p> <p>2016-07-01</p> <p>Practical collaboration at the intersection of education and neuroscience research is difficult because the combined discipline encompasses both the activity of microscopic neurons and the complex social interactions of teachers and students in a classroom. Taking a pragmatic view, this paper discusses three education objectives to which neuroscience can be effectively applied: optimising, <span class="hlt">generalising</span> and integrating instructional techniques. These objectives are characterised by: (1) being of practical importance; (2) building on existing education and cognitive research; and (3) being infeasible to address based on behavioural experiments alone. The focus of the neuroscientific aspect of collaborative research should be on the activity of the brain before, during and after learning a task, as opposed to performance of a task. The objectives are informed by literature that highlights possible pitfalls with educational neuroscience research, and are described with respect to the static and dynamic aspects of brain physiology that can be measured by current technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ConSc..28..217W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ConSc..28..217W"><span>Visceral obesity and psychosocial stress: a <span class="hlt">generalised</span> control theory model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wallace, Rodrick</p> <p>2016-07-01</p> <p>The linking of control theory and information theory via the Data Rate Theorem and its <span class="hlt">generalisations</span> allows for construction of necessary conditions statistical models of body mass regulation in the context of interaction with a complex dynamic environment. By focusing on the stress-related induction of central obesity via failure of HPA axis regulation, we explore implications for strategies of prevention and treatment. It rapidly becomes evident that individual-centred biomedical reductionism is an inadequate paradigm. Without mitigation of HPA axis or related dysfunctions arising from social pathologies of power imbalance, economic insecurity, and so on, it is unlikely that permanent changes in visceral obesity for individuals can be maintained without constant therapeutic effort, an expensive - and likely unsustainable - public policy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010LNCS.5989..131M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010LNCS.5989..131M"><span>ProGolem: A System Based on Relative Minimal <span class="hlt">Generalisation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muggleton, Stephen; Santos, José; Tamaddoni-Nezhad, Alireza</p> <p></p> <p>Over the last decade Inductive Logic Programming systems have been dominated by use of top-down refinement search techniques. In this paper we re-examine the use of bottom-up approaches to the construction of logic programs. In particular, we explore variants of Plotkin's Relative Least General <span class="hlt">Generalisation</span> (RLGG) which are based on subsumption relative to a bottom clause. With Plotkin's RLGG, clause length grows exponentially in the number of examples. By contrast, in the Golem system, the length of ij-determinate RLGG clauses were shown to be polynomially bounded for given values of i and j. However, the determinacy restrictions made Golem inapplicable in many key application areas, including the learning of chemical properties from atom and bond descriptions. In this paper we show that with Asymmetric Relative Minimal <span class="hlt">Generalisations</span> (or ARMGs) relative to a bottom clause, clause length is bounded by the length of the initial bottom clause. ARMGs, therefore do not need the determinacy restrictions used in Golem. An algorithm is described for constructing ARMGs and this has been implemented in an ILP system called ProGolem which combines bottom-clause construction in Progol with a Golem control strategy which uses ARMG in place of determinate RLGG. ProGolem has been evaluated on several well-known ILP datasets. It is shown that ProGolem has a similar or better predictive accuracy and learning time compared to Golem on two determinate real-world applications where Golem was originally tested. Moreover, ProGolem was also tested on several non-determinate real-world applications where Golem is inapplicable. In these applications, ProGolem and Aleph have comparable times and accuracies. The experimental results also suggest that ProGolem significantly outperforms Aleph in cases where clauses in the target theory are long and complex.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AnGeo..34..557T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AnGeo..34..557T"><span><span class="hlt">Generalised</span> partition functions: inferences on phase space distributions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Treumann, Rudolf A.; Baumjohann, Wolfgang</p> <p>2016-06-01</p> <p>It is demonstrated that the statistical mechanical partition function can be used to construct various different forms of phase space distributions. This indicates that its structure is not restricted to the Gibbs-Boltzmann factor prescription which is based on counting statistics. With the widely used replacement of the Boltzmann factor by a <span class="hlt">generalised</span> Lorentzian (also known as the q-deformed exponential function, where κ = 1/|q - 1|, with κ, q ∈ R) both the kappa-Bose and kappa-Fermi partition functions are obtained in quite a straightforward way, from which the conventional Bose and Fermi distributions follow for κ → ∞. For κ ≠ ∞ these are subject to the restrictions that they can be used only at temperatures far from zero. They thus, as shown earlier, have little value for quantum physics. This is reasonable, because physical κ systems imply strong correlations which are absent at zero temperature where apart from stochastics all dynamical interactions are frozen. In the classical large temperature limit one obtains physically reasonable κ distributions which depend on energy respectively momentum as well as on chemical potential. Looking for other functional dependencies, we examine Bessel functions whether they can be used for obtaining valid distributions. Again and for the same reason, no Fermi and Bose distributions exist in the low temperature limit. However, a classical Bessel-Boltzmann distribution can be constructed which is a Bessel-modified Lorentzian distribution. Whether it makes any physical sense remains an open question. This is not investigated here. The choice of Bessel functions is motivated solely by their convergence properties and not by reference to any physical demands. This result suggests that the Gibbs-Boltzmann partition function is fundamental not only to Gibbs-Boltzmann but also to a large class of <span class="hlt">generalised</span> Lorentzian distributions as well as to the corresponding nonextensive statistical mechanics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Independence+AND+Day&pg=4&id=EJ976733','ERIC'); return false;" href="http://eric.ed.gov/?q=Independence+AND+Day&pg=4&id=EJ976733"><span>The Role of Memory Consolidation in <span class="hlt">Generalisation</span> of New Linguistic Information</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Tamminen, Jakke; Davis, Matthew H.; Merkx, Marjolein; Rastle, Kathleen</p> <p>2012-01-01</p> <p>Accounts of memory that postulate complementary learning systems (CLS) have become increasingly influential in the field of language learning. These accounts predict that <span class="hlt">generalisation</span> of newly learnt linguistic information to untrained contexts requires offline memory consolidation. Such <span class="hlt">generalisation</span> should not be observed immediately after…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUSMGP41A..09E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUSMGP41A..09E"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> and cyclostratigraphy of upper Jurassic marly formations (ANDRA, underground research laboratory, Bure, Eastern Paris Basin): Record of Milankovitch cycles, sedimentary gaps, and implications for regional correlation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Emilia, H.; Bruno, G.; Pierre-Yves, C.; Slah, B.; Pascal, E.; Linda, H.; Christian, R.</p> <p>2006-05-01</p> <p>This study integrates research conducted by ANDRA at the Underground Research Laboratory of Bure (Meuse, France) to investigate the feasibility of a deep geological waste repository in clay for high-level and long-lived intermediate-level radioactive waste. The aim of this study is to detect possible sedimentary gaps in the upper Callovian-lower Oxfordian homogeneous marly formation where the laboratory is located, and to estimate the duration of stages and biostratigraphic zonation by comparison with a basin sequence from the southeast of France that is presumed to have accumulated continuously. The search for hiatuses was made using a high resolution cyclostratigraphic approach based on the study of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (MS) fluctuations. Four ANDRA boreholes (EST 342, EST 322, EST 103 and EST 312) oriented on a SW-NE transect (40 kilometers) were analyzed. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> measurements were made on core samples with a Bartington Instruments MS2E1 sensor every 4 centimeters. Sedimentological data suggest that variations of the clay content influence the long term evolution of MS. The high frequency variations in MS were subjected to spectral analysis. Composite cycles of 0.5, 1 and 2.5 m thickness were recognized on the basis of frequency ratio and correspond to the frequency ratio of orbital Milankovitch cycles. The duration of the Mariae ammonite zone in the Paris Basin was estimated by counting the cycles, to be between 2.4 and 2.6 My ± 0.3 ky (borehole EST 322 & EST 103). The amplitude spectrum shows (1) sedimentation rate variations in particular in the lower Oxfordian and (2) interruptions in cycle evolution correlated to sequential limits. We interpret these zones as short condensed levels. The same methods were applied to sections from the southeast of France (Aspres-sur-Buëch, Thuoux), and the Mariae ammonite zone estimated to be between 2.3 and 2.8 My of age. By comparison of this biostratigraphic zone between the two studied regions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22443403','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22443403"><span>Two isostructural layered oxohalide compounds containing Mn{sup 2+}, Te{sup 4+} and Si{sup 4+}; crystal structure and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zimmermann, Iwan; Kremer, Reinhard K.; Johnsson, Mats</p> <p>2014-10-15</p> <p>The new compounds Mn{sub 4}(TeO{sub 3})(SiO{sub 4})X{sub 2} (X=Br, Cl) were synthesized by solid state reactions in sealed evacuated silica tubes. The compounds crystallize in the monoclinic space group P2{sub 1}/m with the unit cell parameters a=5.5463(3) Å (5.49434(7) Å), b=6.4893(4) Å (6.44184(9) Å), c=12.8709(7) Å (12.60451(18) Å), β=93.559(5)° (94.1590(12)°) and Z=2 for the respective Br and Cl analogues. Manganese adopts various distorted coordination polyhedra; [MnO{sub 6}] octahedra, [MnO{sub 5}] tetragonal pyramids and [MnO{sub 2}X{sub 2}] tetrahedra. Other building blocks are [SiO{sub 4}] tetrahedra and [TeO{sub 3}] trigonal pyramids. The structure is made up from layers having no net charge that are connected via weak Van der Waal interactions. The layers that are parallel to (1 1 0) consist of two manganese oxide sheets which are separated by [SiO{sub 4}] tetrahedra. On the outer sides of the sheets are the [MnO{sub 2}X{sub 2}] tetrahedra and the [TeO{sub 3}] trigonal pyramids connected so that the halide ions and the stereochemically active lone pairs on the tellurium atoms protrude from the layers. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> measurements reveal a Curie law with a Weiss temperature of θ=−153(3) K for temperatures ≥100 K and indicate antiferromagnetic ordering at T{sub N} ∼4 K. Possible structural origins of the large frustration parameter of f=38 are discussed. - Graphical abstract: Table of contents caption. The new compounds Mn{sub 4}(TeO{sub 3})(SiO{sub 4})X{sub 2} (X=Br, Cl) are layered with weak Van der Waal interactions in between the layers. Manganese adopts various distorted coordination polyhedral, other building blocks are [SiO{sub 4}] tetrahedra and [TeO{sub 3}] trigonal pyramids. <span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> measurements indicate antiferromagnetic ordering at low temperatures and a large frustration parameter. - Highlights: • Two new isostructural oxohalide compounds are described. • The compounds are the first examples of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20900910','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20900910"><span>Synthesis, structure, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and Mossbauer and Raman spectroscopies of the new oxyphosphate Fe{sub 0.50}TiO(PO{sub 4})</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Benmokhtar, S. . E-mail: s.benmokhtar@univh2m.ac.ma; El Jazouli, A.; Chaminade, J.P.; Gravereau, P.; Wattiaux, A.; Fournes, L.; Grenier, J.C.; Waal, D.</p> <p>2006-12-15</p> <p>A new iron titanyl oxyphosphate Fe{sub 0.50}TiO(PO{sub 4}) was synthesized by both solid-state reaction and Cu{sup 2+}-Fe{sup 2+} ion exchange method. The material was then characterized by X-ray diffraction, Mossbauer spectroscopy, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements and Raman spectroscopy. The crystal structure of the compound was refined, using X-ray powder diffraction data, by Rietveld profile method; it crytallizes in the monoclinic system, space group P2{sub 1}/c (No.14), with a=7.4039(3)A, b=7.3838(3)A, c=7.4083(3)A, {beta}=120.36{sup o}(1), V=349.44(2)A{sup 3} and Z=4. The volume of the title compound is comparable to those of the M{sub 0.50}{sup II}TiO(PO{sub 4}) series, where M{sup II}=Mg, Co, Ni and Zn. The framework is built up from [TiO{sub 6}] octahedra and [PO{sub 4}] tetrahedra. [TiO{sub 6}] octahedra are linked together by corners and form infinite chains along the c-axis. Ti atoms are displaced from the center of octahedral units showing an alternating short distance (1.73A) and a long one (2.22A). These chains are linked together by [PO{sub 4}] tetrahedra. Fe{sup 2+} cations occupy a triangle-based antiprism sharing two faces with two [TiO{sub 6}] octahedra. Mossbauer and <span class="hlt">magnetic</span> measurements show the existence of iron only in divalent state, located exclusively in octahedral sites with high spin confition (t{sub 2g}{sup 4}e{sub g}{sup 2}). Raman study confirms the existence of Ti-O-Ti chains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25982910','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25982910"><span>How can [Mo(IV)(CN)6](2-), an apparently octahedral (d)(2) complex, be diamagnetic? Insights from quantum chemical calculations and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Radoń, Mariusz; Rejmak, Paweł; Fitta, Magdalena; Bałanda, Maria; Szklarzewicz, Janusz</p> <p>2015-06-14</p> <p>Quantum chemical calculations are employed to elucidate the origin of a puzzling diamagnetism for a hexacyanomolybdate(IV) anion, [Mo(CN)6](2-), which was previously reported by Szklarzewicz et al. [Inorg. Chem., 2007, 46, 9531-9533]. The diamagnetism is surprising because for the octahedral (d)(2) complex one would rather expect a (paramagnetic) triplet ground state, clearly favored over a (diamagnetic) singlet state by an exchange interaction between two d electrons in the t2g orbitals. Nevertheless, the present calculations reveal that the minimum energy structure of isolated [Mo(CN)6](2-) is not an octahedron, but a trigonal prism; the latter geometry allows maximization of a σ-donation from the cyanides to the electron-deficient Mo(iv) center. Unlike for the octahedron, for the trigonal prism structure the singlet and triplet spin states are close in energy to within a few kcal mol(-1). Although the actual relative energy of the two spin states turns out to be method-dependent, the complete active space calculations (CASPT2; with the appropriate choice of the IPEA shift parameter) can reproduce the singlet ground state, in agreement with the experimentally observed diamagnetism. Moreover, <span class="hlt">magnetic</span> measurements reveal a slight increase of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> with the increase of temperature from 100 to 300 K, suggesting an admixture of a thermally induced paramagnetism (possibly due to Boltzmann population of the low-energy triplet state) on top of the dominant diamagnetism. Our prediction that the geometry of [Mo(CN)6](2-) should significantly deviate from the ideal octahedron, not only in the gas phase, but also in a periodic DFT model of the crystalline phase, as well as the experimentally confirmed diamagnetic properties, does not agree with the previously reported ideal octahedral structure. We suggest that this crystal structure might have been determined incorrectly (e.g., due to overlooked merohedral twinning or superstructure properties) and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhRvB..85j4517H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhRvB..85j4517H"><span>Two-component uniform spin <span class="hlt">susceptibility</span> of superconducting HgBa2CuO4+δ single crystals measured using 63Cu and 199Hg nuclear <span class="hlt">magnetic</span> resonance</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Haase, Jürgen; Rybicki, Damian; Slichter, Charles P.; Greven, Martin; Yu, Guichuan; Li, Yuan; Zhao, Xudong</p> <p>2012-03-01</p> <p>63Cu and 199Hg nuclear <span class="hlt">magnetic</span> resonance shifts for an optimally doped and underdoped HgBa2CuO4+δ single crystal are reported, and the temperature dependence dictates a two-component description of the uniform spin <span class="hlt">susceptibility</span>. The first component, associated with the pseudogap phenomenon in the NMR shifts, decreases at room temperature and continues to drop as the temperature is lowered, without a drastic change at the transition temperature into the superconducting state. The second component is temperature independent above the superconducting transition temperature and vanishes rapidly below it. It is a substantial part of the total T-dependent <span class="hlt">susceptibility</span> measured at both nuclei.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22269360','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22269360"><span>Investigation of <span class="hlt">magnetic</span> spin glass property in La{sub 0.5}Bi{sub 0.5}MnO{sub 3} sample using non-linear AC <span class="hlt">susceptibility</span> measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kumar, Punith V. Manju, M. R. Dayal, Vijaylakshmi</p> <p>2014-04-24</p> <p>We present a comprehensive study on origin of Spin Glass (SG) property in polycrystalline La{sub 0.5}Bi{sub 0.5}MnO{sub 3} perovskite oxide using linear and higher order ac <span class="hlt">susceptibility</span> (χ) measurements. The third order harmonic <span class="hlt">susceptibility</span> (χ{sub 3}) vs. temperature (K) with varying <span class="hlt">magnetic</span> fields from 0.95 to 9.45 Oe and the divergence in their χ{sub 3} (max) allows us to infer the SG behavior occurring in the sample possibly due to co-operative freezing of the spins.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22672084','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22672084"><span>Regional and voxel-wise comparisons of blood flow measurements between dynamic <span class="hlt">susceptibility</span> contrast <span class="hlt">magnetic</span> resonance imaging (DSC-MRI) and arterial spin labeling (ASL) in brain tumors.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>White, Carissa M; Pope, Whitney B; Zaw, Taryar; Qiao, Joe; Naeini, Kourosh M; Lai, Albert; Nghiemphu, Phioanh L; Wang, J J; Cloughesy, Timothy F; Ellingson, Benjamin M</p> <p>2014-01-01</p> <p>The objective of the current study was to evaluate the regional and voxel-wise correlation between dynamic <span class="hlt">susceptibility</span> contrast (DSC) and arterial spin labeling (ASL) perfusion <span class="hlt">magnetic</span> resonance imaging (MRI) measurement of cerebral blood flow (CBF) in patients with brain tumors. Thirty patients with histologically verified brain tumors were evaluated in the current study. DSC-MRI was performed by first using a preload dose of gadolinium contrast, then collecting a dynamic image acquisition during a bolus of contrast, followed by posthoc contrast agent leakage correction. Pseudocontinuous ASL was collected using 30 pairs of tag and control acquisition using a 3-dimensional gradient-echo spin-echo (GRASE) acquisition. All images were registered to a high-resolution anatomical atlas. Average CBF measurements within regions of contrast-enhancement and T2 hyperintensity were evaluated between the two modalities. Additionally, voxel-wise correlation between CBF measurements obtained with DSC and ASL were assessed. Results demonstrated a positive linear correlation between DSC and ASL measurements of CBF when regional average values were compared; however, a statistically significant voxel-wise correlation was only observed in around 30-40% of patients. These results suggest DSC and ASL may provide regionally similar, but spatially different measurements of CBF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015FrEaS...3...40W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015FrEaS...3...40W"><span>Contribution of Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> (AMS) to reconstruct flooding characteristics of a 4220 BP tsunami from a thick unconsolidated structureless deposit (Banda Aceh, Sumatra)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wassmer, Patrick; Gomez, Christopher; Iskandasyah, T. Yan W. M.; Lavigne, Franck; Sartohadi, Junun</p> <p>2015-07-01</p> <p>One of the main concerns of deciphering tsunami sedimentary records along seashore is to link the emplaced layers with marine high energy events. Based on a combination of morphologic features, sedimentary figures, grain size characteristics, fossils content, microfossils assemblages, geochemical elements, heavy minerals presence; it is, in principle, possible to relate the sedimentary record to a tsunami event. However, experience shows that sometimes, in reason of a lack of any visible sedimentary features, it is hard to decide between a storm and a tsunami origin. To solve this issue, the authors have used the Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> (AMS) to evidence the sediment fabric. The validity of the method for reconstructing flow direction has been proved when applied on sediments in the aftermath of a tsunami event, for which the behaviour was well documented (2004 IOT). We present herein an application of this method for a 56 cm thick paleo-deposit dated 4220 BP laying under the soil covered by the 2004 IOT, SE of Banda Aceh, North Sumatra. We analysed this homogenous deposit, lacking of any visible structure, using methods of classic sedimentology to confirm the occurrence of a high energy event. We then applied AMS technique that allowed the reconstruction of flow characteristics during sediment emplacement. We show that all the sequence was emplaced by uprush phases and that the local topography played a role on the re-orientation of a part of the uprush flow, creating strong reverse current. This particular behaviour was reported by eyewitnesses during the 2004 IOT event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920037479&hterms=Magnesium&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMagnesium','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920037479&hterms=Magnesium&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMagnesium"><span>Dissociation of O(2-)2 defects into paramagnetic O(-) in wide band-gap insulators - A <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> study of magnesium oxide</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Batllo, F.; Leroy, R. C.; Parvin, K.; Freund, F.</p> <p>1990-01-01</p> <p>The <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of single-crystal MgO has been measured in the temperature range 300-1000 K, using a Faraday balance. The high-purity crystal (less than 100 ppm transition metals), grown from the melt in a H2O-containing atmosphere, was found to be paramagnetic due to the presence of defects on the O(2-) sublattice. The defects derive from OH(-) introduced into the MgO matrix by the dissolution of traces of H2O during crystal growth. The OH(-) converts into O(2-)2 and H2. Each O(2-)2 represents two coupled, spin-paired O(-) states. The observed strongly temperature-dependent paramagnetism can be described by three contributions that overlay the intrinsic diamagnetism of MgO and arise from the low level of transition-metal impurities, O(-) generated by 0(2-)2 dissociation, and O(-) states trapped by quenching from high temperatures from previous experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJEaS.106..631F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJEaS.106..631F"><span>Vertical-axis rotations and deformation along the active strike-slip El Tigre Fault (Precordillera of San Juan, Argentina) assessed through palaeomagnetism and anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fazzito, Sabrina Y.; Rapalini, Augusto E.; Cortés, José M.; Terrizzano, Carla M.</p> <p>2017-03-01</p> <p>Palaeomagnetic data from poorly consolidated to non-consolidated late Cenozoic sediments along the central segment of the active El Tigre Fault (Central-Western Precordillera of the San Juan Province, Argentina) demonstrate broad cumulative deformation up to 450 m from the fault trace and reveal clockwise and anticlockwise vertical-axis rotations of variable magnitude. This deformation has affected in different amounts Miocene to late Pleistocene samples and indicates a complex kinematic pattern. Several inherited linear structures in the shear zone that are oblique to the El Tigre Fault may have acted as block boundary faults. Displacement along these faults may have resulted in a complex pattern of rotations. The maximum magnitude of rotation is a function of the age of the sediments sampled, with largest values corresponding to middle Miocene-lower Pliocene deposits and minimum values obtained from late Pleistocene deposits. The kinematic study is complemented by low-field anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> data to show that the local strain regime suggests a N-S stretching direction, subparallel to the strike of the main fault.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25516146','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25516146"><span>Is the <span class="hlt">Susceptibility</span> Vessel Sign on 3-Tesla <span class="hlt">Magnetic</span> Resonance T2*-Weighted Imaging a Useful Tool to Predict Recanalization in Intravenous Tissue Plasminogen Activator?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yamamoto, N; Satomi, J; Harada, M; Izumi, Y; Nagahiro, S; Kaji, R</p> <p>2016-09-01</p> <p>The aim of this study was to investigate the independent factors associated with the absence of recanalization approximately 24 h after intravenous administration of tissue-type plasminogen activator (IV TPA). The previous studies have been conducted using 1.5-Tesla (T) <span class="hlt">magnetic</span> resonance imaging (MRI). We studied whether the characteristics of 3-T MRI findings were useful to predict outcome and recanalization after IV tPA. Patients with internal carotid artery (ICA) or middle cerebral artery (MCA) (horizontal portion, M1; Sylvian portion, M2) occlusion and treated by IV tPA were enrolled. We studied whether the presence of <span class="hlt">susceptibility</span> vessel sign (SVS) at M1 and low clot burden score on T2*-weighted imaging (T2*-CBS) on 3-T MRI were associated with the absence of recanalization. A total of 49 patients were enrolled (27 men; mean age, 73.9 years). MR angiography obtained approximately 24 h after IV tPA revealed recanalization in 21 (42.9 %) patients. Independent factors associated with the absence of recanalization included ICA or proximal M1 occlusion (odds ratio, 69.6; 95 % confidence interval, 5.05-958.8, p = 0.002). In this study, an independent factor associated with the absence of recanalization may be proximal occlusion of the cerebral arteries rather than SVS in the MCA or low T2*-CBS on 3-T MRI.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJEaS.tmp...37F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJEaS.tmp...37F"><span>Vertical-axis rotations and deformation along the active strike-slip El Tigre Fault (Precordillera of San Juan, Argentina) assessed through palaeomagnetism and anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fazzito, Sabrina Y.; Rapalini, Augusto E.; Cortés, José M.; Terrizzano, Carla M.</p> <p>2016-05-01</p> <p>Palaeomagnetic data from poorly consolidated to non-consolidated late Cenozoic sediments along the central segment of the active El Tigre Fault (Central-Western Precordillera of the San Juan Province, Argentina) demonstrate broad cumulative deformation up to ~450 m from the fault trace and reveal clockwise and anticlockwise vertical-axis rotations of variable magnitude. This deformation has affected in different amounts Miocene to late Pleistocene samples and indicates a complex kinematic pattern. Several inherited linear structures in the shear zone that are oblique to the El Tigre Fault may have acted as block boundary faults. Displacement along these faults may have resulted in a complex pattern of rotations. The maximum magnitude of rotation is a function of the age of the sediments sampled, with largest values corresponding to middle Miocene-lower Pliocene deposits and minimum values obtained from late Pleistocene deposits. The kinematic study is complemented by low-field anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> data to show that the local strain regime suggests a N-S stretching direction, subparallel to the strike of the main fault.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JMPSo..59.1576S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JMPSo..59.1576S"><span>The bimodal theory of plasticity: A form-invariant <span class="hlt">generalisation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Soldatos, Kostas P.</p> <p>2011-08-01</p> <p>The bimodal plasticity model of fibre-reinforced materials is currently available and applicable only in association with thin-walled fibrous composites containing a family of straight fibres which are conveniently assumed parallel with the x1-axis of an appropriately chosen Cartesian co-ordinate system. Based on reliable experimental evidence, the model suggests that plastic slip in the composite operates in two distinct modes; the so-called matrix dominated mode (MDM) which depends on a matrix yield stress, and the fibre dominated mode (FDM) which depends also on the fibre yield stress. Each mode is activated by different states of applied stress, has its own yield surface (or surfaces) in the stress space and has its own segment on the overall yield surface of the composite. This paper employs theory of tensor representations and produces a form-invariant <span class="hlt">generalisation</span> of both modes of the model. This <span class="hlt">generalisation</span> furnishes the model with direct applicability to relevant plasticity problems, regardless of the shape of the fibres or the orientation of the co-ordinate system. It thus provides a proper mathematical foundation that underpins important physical concepts associated with the model while it also elucidates several technical relevant issues. A most interesting of those issues is the revelation that activation of the MDM plastic regime is possible only if the applied stress state allows the fibres to act like they are practically inextensible. Moreover, activation of the more dominant, between the two MDM plastic slip branches is possible only if conditions of material incompressibility hold, in addition to the implied condition of fibre inextensibility. A direct mathematical connection is thus achieved between basic, experimentally verified concepts of the bimodal plasticity model and a relevant mathematical model originated earlier from the theory of ideal fibre-reinforced materials. An additional issue of discussion involves the number of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PApGe.165.1411B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PApGe.165.1411B"><span>Induced <span class="hlt">Magnetization</span> of Magnetite-titanomagnetite in Alternating Fields Ranging from 400 A/m to 80,000 A/m; Low-field <span class="hlt">Susceptibility</span> (100 400 A/m) and Beyond</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borradaile, Graham J.; Stupavsky, Mike; Metsaranta, Dawn-Ann</p> <p>2008-07-01</p> <p>For remanence-bearing minerals (RBM) such as magnetite-titanomagnetite, <span class="hlt">susceptibility</span> to induced <span class="hlt">magnetism</span> ( M) measured in alternating fields ( H AC ) is field-dependent. However, for fields ≤ 400 A/m, measured in an AC induction coil instrument (at 19,100 Hz), <span class="hlt">susceptibility</span> k 0 = M/H AC is sufficiently linear to provide a reproducible rock (or mineral) <span class="hlt">magnetic</span> characteristic and its anisotropy may be related to arrangements of minerals in rock, or for single mineral grains to their crystalline or shape anisotropy. For any remanence-bearing mineral at higher fields k HF (= M/H AC ) is not constant and the term <span class="hlt">susceptibility</span> is not normally used. This study bridges the responses between traditional low-field <span class="hlt">susceptibility</span> measurements and those due to high applied fields, for example when studying hysteresis or saturation <span class="hlt">magnetization</span> of RBM. Where | k HF | is measured in alternating fields that peak significantly above 400 A/m the M(H AC ) relation is forced to follow a hysteresis loop in which | k HF | > k 0 for small | H AC | and where | k HF | decreases to zero for very large fields that achieve saturation <span class="hlt">magnetization</span>. Hysteresis nonlinearity is due to remanence acquired with one field direction requiring a reverse field for its cancellation. We investigate the transition from initial, traditional “low-field” <span class="hlt">susceptibility</span> ( k 0 ) measurements at 60 A/m, through 24 different fields from 400 A/m to 40,000 A/m (for very high k 0 to 80,000 A/m). This reveals M(H AC ) dependence beyond from conventional k 0 through the range of hysteresis behavior in fields equal to and exceeding that required to achieve saturation <span class="hlt">magnetization</span> ( M S ). We show k HF increases with peak H AC until the peak field is slightly less than saturation <span class="hlt">magnetization</span> in natural rock samples rich in magnetite (TM0 = Fe3O4) and TM60 (Fe2.4Ti0.6O4). All sample suites predominantly contain multidomain grains with subordinate pseudo-single domain and single-domain grains. k/k 0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24942107','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24942107"><span>Interpretation of human pointing by African elephants: <span class="hlt">generalisation</span> and rationality.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Smet, Anna F; Byrne, Richard W</p> <p>2014-11-01</p> <p>Factors influencing the abilities of different animals to use cooperative social cues from humans are still unclear, in spite of long-standing interest in the topic. One of the few species that have been found successful at using human pointing is the African elephant (Loxodonta africana); despite few opportunities for learning about pointing, elephants follow a pointing gesture in an object-choice task, even when the pointing signal and experimenter's body position are in conflict, and when the gesture itself is visually subtle. Here, we show that the success of captive African elephants at using human pointing is not restricted to situations where the pointing signal is sustained until the time of choice: elephants followed human pointing even when the pointing gesture was withdrawn before they had responded to it. Furthermore, elephants rapidly <span class="hlt">generalised</span> their response to a type of social cue they were unlikely to have seen before: pointing with the foot. However, unlike young children, they showed no sign of evaluating the 'rationality' of this novel pointing gesture according to its visual context: that is, whether the experimenter's hands were occupied or not.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013IJC....86.1990D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013IJC....86.1990D"><span>Some <span class="hlt">generalisations</span> of linear-graph modelling for dynamic systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Silva, Clarence W.; Pourazadi, Shahram</p> <p>2013-11-01</p> <p>Proper modelling of a dynamic system can benefit analysis, simulation, design, evaluation and control of the system. The linear-graph (LG) approach is suitable for modelling lumped-parameter dynamic systems. By using the concepts of graph trees, it provides a graphical representation of the system, with a direct correspondence to the physical component topology. This paper systematically extends the application of LGs to multi-domain (mixed-domain or multi-physics) dynamic systems by presenting a unified way to represent different domains - mechanical, electrical, thermal and fluid. Preservation of the structural correspondence across domains is a particular advantage of LGs when modelling mixed-domain systems. The <span class="hlt">generalisation</span> of Thevenin and Norton equivalent circuits to mixed-domain systems, using LGs, is presented. The structure of an LG model may follow a specific pattern. Vector LGs are introduced to take advantage of such patterns, giving a general LG representation for them. Through these vector LGs, the model representation becomes simpler and rather compact, both topologically and parametrically. A new single LG element is defined to facilitate the modelling of distributed-parameter (DP) systems. Examples are presented using multi-domain systems (a motion-control system and a flow-controlled pump), a multi-body mechanical system (robot manipulator) and DP systems (structural rods) to illustrate the application and advantages of the methodologies developed in the paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ExG....46..349S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ExG....46..349S"><span>Imaging tilted transversely isotropic media with a <span class="hlt">generalised</span> screen propagator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shin, Sung-Il; Byun, Joongmoo; Seol, Soon Jee</p> <p>2015-01-01</p> <p>One-way wave equation migration is computationally efficient compared with reverse time migration, and it provides a better subsurface image than ray-based migration algorithms when imaging complex structures. Among many one-way wave-based migration algorithms, we adopted the <span class="hlt">generalised</span> screen propagator (GSP) to build the migration algorithm. When the wavefield propagates through the large velocity variation in lateral or steeply dipping structures, GSP increases the accuracy of the wavefield in wide angle by adopting higher-order terms induced from expansion of the vertical slowness in Taylor series with each perturbation term. To apply the migration algorithm to a more realistic geological structure, we considered tilted transversely isotropic (TTI) media. The new GSP, which contains the tilting angle as a symmetric axis of the anisotropic media, was derived by modifying the GSP designed for vertical transversely isotropic (VTI) media. To verify the developed TTI-GSP, we analysed the accuracy of wave propagation, especially for the new perturbation parameters and the tilting angle; the results clearly showed that the perturbation term of the tilting angle in TTI media has considerable effects on proper propagation. In addition, through numerical tests, we demonstrated that the developed TTI-GS migration algorithm could successfully image a steeply dipping salt flank with high velocity variation around anisotropic layers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMPP31C1766B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMPP31C1766B"><span>Assessment of climatic and seismic cycles in southern chile from high resolution XRF and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements of historic lake sediments.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boes, X.; Hubert-Ferrari, A.; Fagel, N.</p> <p>2006-12-01</p> <p>The high-resolution sedimentological studies performed on the sediment cores collected in the oceans or in the lakes constitutes the basis for inter-comparison of past climate variability. Among the new high-resolution approaches, the X-Ray Fluorescence (XRF) analysis of varved marine and lacustrine cores represents some of the best resolution. These data are particularly useful for tracking short-term climate changes expressed with calibrated time scales. However, the XRF results obtain on the fresh cores surface may be of low resolution because the core material is wet and unconsolidated. One particularly attractive method to solve this problem consists of impregnating the sediment cores with polymers in order to polish the core surface for XRF analyses. This step is essential for being able to get significant XRF and <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> (MS) results in the muddy cores. Since the 1960s, the evolution of sediment impregnation methods has been strongly linked to the development of innovative techniques (e.g., sampling devices, cryogenic and vacuum technologies, polymers, etc.). In this communication, we first propose a revised method that may be applied to prepare sediment cores for high-resolution XRF and MS data acquisition. Then we show an example of XRF and MS results obtain on laminated lake sediments from South America (Lago Puyehue, 40°S). As this area is very sensitive in terms of precipitation change (i.e., Southern Westerlies); the XRF data are compared with the regional instrumental precipitation database. The results are discussed in terms of climate and sismo- tectonic impacts over historic times. Our results shows that, in order to better interpret XRF tool over long sequences, the measurements should be first "calibrated" according to instrumental data such as precipitation, temperatures, and earthquake magnitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3235505','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3235505"><span>Fast and Tissue-Optimized Mapping of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> and T2* with Multi-Echo and Multi-Shot Spirals</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wu, Bing; Li, Wei; Avram, Alexandru Vlad; Gho, Sung-Min; Liu, Chunlei</p> <p>2011-01-01</p> <p>Gradient-echo MRI of resonance-frequency shift and T2* values exhibits unique tissue contrast and offers relevant physiological information. However, acquiring 3D-phase images and T2* maps [A1] with the standard spoiled gradient echo (SPGR) sequence is lengthy for routine imaging at high-spatial resolution and whole-brain coverage. In addition, with the standard SPGR sequence, optimal signal-to-noise ratio (SNR) cannot be achieved for every tissue type given their distributed resonance frequency and T2* value. To address these two issues, a SNR optimized multi-echo sequence with a stack-of-spiral acquisition is proposed and implemented for achieving fast and simultaneous acquisition of image phase and T2* maps. The analytical behavior of the phase SNR is derived as a function of resonance frequency, T2* and echo time. This relationship is utilized to achieve tissue optimized SNR by combining phase images with different echo times. Simulations and in vivo experiments were designed to verify the theoretical predictions. Using the multi-echo spiral acquisition, whole-brain coverage with 1 mm isotropic resolution can be achieved within 2.5 minutes, shortening the scan time by a factor of 8. The resulting multi-echo phase map shows similar SNR to that of the standard SPGR. The acquisition can be further accelerated with non-Cartesian parallel imaging. The technique can be readily extended to other multi-shot readout trajectories besides spiral. It may provide a practical acquisition strategy for high resolution and simultaneous 3D mapping of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and T2*. PMID:21784162</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21491593','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21491593"><span>Potential for Differentiation of Pseudoprogression From True Tumor Progression With Dynamic <span class="hlt">Susceptibility</span>-Weighted Contrast-Enhanced <span class="hlt">Magnetic</span> Resonance Imaging Using Ferumoxytol vs. Gadoteridol: A Pilot Study</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gahramanov, Seymur; Raslan, Ahmed M.; Muldoon, Leslie L.; Hamilton, Bronwyn E.; Rooney, William D.; Varallyay, Csanad G.; Njus, Jeffrey M.; Haluska, Marianne; Neuwelt, Edward A.</p> <p>2011-02-01</p> <p>Purpose: We evaluated dynamic <span class="hlt">susceptibility</span>-weighted contrast-enhanced <span class="hlt">magnetic</span> resonance imaging (DSC-MRI) using gadoteridol in comparison to the iron oxide nanoparticle blood pool agent, ferumoxytol, in patients with glioblastoma multiforme (GBM) who received standard radiochemotherapy (RCT). Methods and Materials: Fourteen patients with GBM received standard RCT and underwent 19 MRI sessions that included DSC-MRI acquisitions with gadoteridol on Day 1 and ferumoxytol on Day 2. Relative cerebral blood volume (rCBV) values were calculated from DSC data obtained from each contrast agent. T1-weighted acquisition post-gadoteridol administration was used to identify enhancing regions. Results: In seven MRI sessions of clinically presumptive active tumor, gadoteridol-DSC showed low rCBV in three and high rCBV in four, whereas ferumoxytol-DSC showed high rCBV in all seven sessions (p = 0.002). After RCT, seven MRI sessions showed increased gadoteridol contrast enhancement on T1-weighted scans coupled with low rCBV without significant differences between contrast agents (p = 0.9). Based on post-gadoteridol T1-weighted scans, DSC-MRI, and clinical presentation, four patterns of response to RCT were observed: regression, pseudoprogression, true progression, and mixed response. Conclusion: We conclude that DSC-MRI with a blood pool agent such as ferumoxytol may provide a better monitor of tumor rCBV than DSC-MRI with gadoteridol. Lesions demonstrating increased enhancement on T1-weighted MRI coupled with low ferumoxytol rCBV are likely exhibiting pseudoprogression, whereas high rCBV with ferumoxytol is a better marker than gadoteridol for determining active tumor. These interesting pilot observations suggest that ferumoxytol may differentiate tumor progression from pseudoprogression and warrant further investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Tecto..35.1015A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Tecto..35.1015A"><span>Tectonic insight based on anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> and compaction studies in the Sierras Australes thrust and fold belt (southwest Gondwana boundary, Argentina)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arzadún, Guadalupe; Tomezzoli, Renata N.; Cesaretti, Nora N.</p> <p>2016-04-01</p> <p>The Sierras Australes fold and thrust belt (Buenos Aires Province, Argentina) was in the southwestern Gondwanaland margin during the Paleozoic. The Tunas Formation (Permian) is exposed along the eastern part of it and continues eastward beneath the Claromecó Basin. Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) and compaction studies are described and compared with previous paleomagnetic studies with the aim of determining direction and magnitude of the main stresses acting during the sedimentation of the Tunas Formation. The anisotropy ellipsoids are triaxial with oblate or prolate shapes, reflecting different stages of layer parallel shortening during the evolution of the basin. Kmax axes trend NW-SE, parallel to the fold axes, while Kmin move from a horizontal (base) to a vertical orientation at the top of the succession, showing a change from a tectonic to almost a sedimentary fabric. The magnitude of anisotropy and compaction degree decreases toward the top of the succession. The AMS results are consistent with the outcrop structural observations and the compaction and paleomagnetic data. Regional pattern indicates a compression from the SW along this part of Gondwana, with a migration of the orogenic front and attenuation toward the NE in the foreland basin during the Upper Paleozoic. This deformation, locally assigned to the San Rafael noncollisional orogenic phase, is the result of the latitudinal movements toward the Equator of Gondwana (southern plates) and Laurentia (northern plates) during the Permian. This movement is the result of a rearrangement of the microplates that collided with Gondwana during the Late Devonian, to configure Pangea during the Triassic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AIPC.1113..260L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AIPC.1113..260L"><span>The Use of <span class="hlt">Susceptibility</span>-Weighted <span class="hlt">Magnetic</span> Resonance Imaging to Characterize the Safety Window of Focused Ultrasound Exposure for Localized Blood—Brain-Barrier Disruption</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Hao-Li; Hsu, Po-Hong; Wai, Yau-Yau; Chen, Jin-Chung; Yen, Tzu-Chen; Wang, Jiun-Jie</p> <p>2009-04-01</p> <p>High-intensity focused ultrasound has been discovered to be able to locally and reversibly increase the permeability of the blood—brain barrier (BBB), which can be detected using <span class="hlt">magnetic</span> resonance imaging (MRI). However, side effects such as microhemorrhage, erythrocyte extravasations, or even extensive hemorrhage can also occur. Although current contrast-enhanced T1-weighted MRI can be used to detect the changes in BBB permeability, its efficacy in detecting tissue hemorrhage after focused-ultrasound sonication remains limited. The purpose of this study was to determine the feasibility of using MR <span class="hlt">susceptibility</span>-weighted imaging (SWI) to identify tissue hemorrhage associated with the process of BBB permeability increase and characterize the safety window of acoustic pressure level. Brains of 42 Sprague-Dawley rats were subjected to 107 sonications either unilaterally or bilaterally. Contrast-enhanced T1-weighted images, together with SWI were performed. Tissue damage and hemorrhage were analyzed histologically with light microscopy and staining by Evan's blue, HE staining as well as TUNEL staining. Our results showed that contrast-enhanced T1 weighted imaging is sensitive to the presence of the BBB disrupture, but was unable to differentiate from extensive tissue damage such as hemorrhage. Also, SWI proved to be a superior tool for the realtime monitoring of the presence of hemorrhage, which is essential to the clinical concerns. The safety operation window in vivo in our study indicated a pressure of 0.78 to 1.1 MPa. to increase the BBB permeability successfully without hemorrhage. Potential applications such as drug delivery in the brain might be benefited.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JVGR..302..141B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JVGR..302..141B"><span>Paleoflow directions of a subaqueous lahar deposit around the Miocene Keserűs Hill lava dome complex (North Hungary) as constrained by photo-statistics and anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Biró, T.; Karátson, D.; Márton, E.; Józsa, S.; Bradák, B.</p> <p>2015-09-01</p> <p>A twofold fabric analysis by using photo-statistics on rock surfaces and low-field anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) is presented, making it possible to infer paleoflow directions, which in turn helps to constrain the primary volcanic geomorphology of a deeply eroded mid-Miocene field (Keserűs Hill lava dome group, Visegrád Mountains, North Hungary). The analyses were carried out on the Rám Hill Pumiceous Sandstone (RHPS) that, based on its petrographic features, is considered as a subaqueously emplaced laharic deposit. The observed anisotropic frequencies of clast a-axis azimuths, the good agreement of fabric directions obtained for all and most elongated samples (elongation > 2.5), the good clustering of the declinations of the K1 <span class="hlt">susceptibilities</span> largely corresponding with the result of image analysis, allow to infer reliable flow directions. The obtained large-scale paleoflow paths show a quasi-radial pattern around the central part of the Visegrád Mountains, which quantitatively confirms the previous hypothesis on the volcanic structure, namely a central edifice-topped syn-eruptive topography. The RHPS is characterized by a clast fabric (revealed by photostatistics on cutted rock surfaces considering the lapilli-sized fraction) as strong as in subaerial PDC deposits, but by a significantly weaker <span class="hlt">magnetic</span> fabric. The weak <span class="hlt">magnetic</span> fabric is supposed to be the result of rock heterogeneity, thus the weakening effect of abundant lithic clasts with strong internal <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> anisotropy, different from the shape anisotropy of the clasts and the flow-related <span class="hlt">magnetic</span> fabric of the fine-grained matrix.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25216375','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25216375"><span>Enhancing <span class="hlt">generalisation</span> in biofeedback intervention using the challenge point framework: a case study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hitchcock, Elaine R; Byun, Tara McAllister</p> <p>2015-01-01</p> <p>Biofeedback intervention can help children achieve correct production of a treatment-resistant error sound, but <span class="hlt">generalisation</span> is often limited. This case study suggests that <span class="hlt">generalisation</span> can be enhanced when biofeedback intervention is structured in accordance with a "challenge point" framework for speech-motor learning. The participant was an 11-year-old with residual /r/ misarticulation who had previously attained correct /r/ production through a structured course of ultrasound biofeedback treatment but did not <span class="hlt">generalise</span> these gains beyond the word level. Treatment difficulty was adjusted in an adaptive manner following predetermined criteria for advancing, maintaining, or moving back a level in a multidimensional hierarchy of functional task complexity. The participant achieved and maintained virtually 100% accuracy in producing /r/ at both word and sentence levels. These preliminary results support the efficacy of a semi-structured implementation of the challenge point framework as a means of achieving <span class="hlt">generalisation</span> and maintenance of treatment gains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Potassium&pg=7&id=EJ284580','ERIC'); return false;" href="http://eric.ed.gov/?q=Potassium&pg=7&id=EJ284580"><span><span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span>: A Practical Introduction.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Greenaway, A. M.; Trail, L. E.</p> <p>1983-01-01</p> <p>Describes an experiment in which students: (1) synthesize tris(acetylacetonato)iron(III), tris(diethyldithiocarbamato)iron(III), and chlorobis(diethyldithiocarbmamato)iron(III); (2) are given a sample of potassium hexocyanoferrate(III); and (3) are then asked to measure the room temperature of these samples using the Guoy technique. Background…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GReGr..49...35P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GReGr..49...35P"><span>Viability of variable <span class="hlt">generalised</span> Chaplygin gas: a thermodynamical approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Panigrahi, D.; Chatterjee, S.</p> <p>2017-03-01</p> <p>The viability of the variable <span class="hlt">generalised</span> Chaplygin gas (VGCG) model is analysed from the standpoint of its thermodynamical stability criteria with the help of an equation of state, P = - B/ρ ^{α }, where B = B0V^{-n/3}. Here B0 is assumed to be a positive universal constant, n is a constant parameter and V is the volume of the cosmic fluid. We get the interesting result that if the well-known stability conditions of a fluid is adhered to, the values of n are constrained to be negative definite to make ( partial P/partial V) S <0 & ( partial P/partial V) T <0 throughout the evolution. Moreover the positivity of thermal capacity at constant volume cV as also the validity of the third law of thermodynamics are ensured in this case. For the particular case n = 0 the effective equation of state reduces to Λ CDM model in the late stage of the universe while for n <0 it mimics a phantom-like cosmology which is in broad agreement with the present SNe Ia constraints like VGCG model. The thermal equation of state is discussed and the EoS parameter is found to be an explicit function of temperature only. Further for large volume the thermal equation of state parameter is identical with the caloric equation of state parameter when T → 0. It may also be mentioned that like Santos et al. our model does not admit of any critical points. We also observe that although the earlier model of Lu explains many of the current observational findings of different probes it fails to explain the crucial tests of thermodynamical stability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NJPh...18l3035P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NJPh...18l3035P"><span>Work and entropy production in <span class="hlt">generalised</span> Gibbs ensembles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perarnau-Llobet, Martí; Riera, Arnau; Gallego, Rodrigo; Wilming, Henrik; Eisert, Jens</p> <p>2016-12-01</p> <p>Recent years have seen an enormously revived interest in the study of thermodynamic notions in the quantum regime. This applies both to the study of notions of work extraction in thermal machines in the quantum regime, as well as to questions of equilibration and thermalisation of interacting quantum many-body systems as such. In this work we bring together these two lines of research by studying work extraction in a closed system that undergoes a sequence of quenches and equilibration steps concomitant with free evolutions. In this way, we incorporate an important insight from the study of the dynamics of quantum many body systems: the evolution of closed systems is expected to be well described, for relevant observables and most times, by a suitable equilibrium state. We will consider three kinds of equilibration, namely to (i) the time averaged state, (ii) the Gibbs ensemble and (iii) the <span class="hlt">generalised</span> Gibbs ensemble, reflecting further constants of motion in integrable models. For each effective description, we investigate notions of entropy production, the validity of the minimal work principle and properties of optimal work extraction protocols. While we keep the discussion general, much room is dedicated to the discussion of paradigmatic non-interacting fermionic quantum many-body systems, for which we identify significant differences with respect to the role of the minimal work principle. Our work not only has implications for experiments with cold atoms, but also can be viewed as suggesting a mindset for quantum thermodynamics where the role of the external heat baths is instead played by the system itself, with its internal degrees of freedom bringing coarse-grained observables to equilibrium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JHyd..529.1324H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JHyd..529.1324H"><span>Wave overwash impact on small islands: <span class="hlt">Generalised</span> observations of freshwater lens response and recovery for multiple hydrogeological settings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Holding, Shannon; Allen, Diana M.</p> <p>2015-10-01</p> <p>Wave overwash events have the potential to result in severe consequences to the freshwater resources of small islands as a result of salt contamination of the aquifer. Due to the significant impact of overwash, it is important to characterise the <span class="hlt">susceptibility</span> of small islands to these events. This study uses numerical modelling to evaluate the freshwater lens response and recovery to overwash events for various island hydrogeological settings (island types) observed worldwide. Models were developed for an example of each island type using a fully coupled surface-subsurface, density-dependent flow and solute transport modelling code. A theoretical overwash event was simulated, and the response and recovery of the freshwater lens were observed for 20 years. The freshwater lens response (degree of aquifer contamination) was largely determined by the vadose zone thickness. Lens recovery ranged from 1 to 19 years for the different island types, and was strongly affected by recharge rate. However, the recovery of potable water in the lens (and restoration of a water supply) was dominantly influenced by geological heterogeneities. The model results demonstrate the cumulative impact of the different factors affecting the freshwater lens response and recovery to the overwash event for each island type, and provide a <span class="hlt">generalised</span> assessment of island <span class="hlt">susceptibility</span> to overwash on a global scale, despite limited data availability for many small islands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25683514','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25683514"><span>Kinetic analysis of superparamagnetic iron oxide nanoparticles in the liver of body-temperature-controlled mice using dynamic <span class="hlt">susceptibility</span> contrast <span class="hlt">magnetic</span> resonance imaging and an empirical mathematical model.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Murase, Kenya; Assanai, Purapan; Takata, Hiroshige; Matsumoto, Nozomi; Saito, Shigeyoshi; Nishiura, Motoko</p> <p>2015-06-01</p> <p>The purpose of this study was to develop a method for analyzing the kinetic behavior of superparamagnetic iron oxide nanoparticles (SPIONs) in the murine liver under control of body temperature using dynamic <span class="hlt">susceptibility</span> contrast <span class="hlt">magnetic</span> resonance imaging (DSC-MRI) and an empirical mathematical model (EMM). First, we investigated the influence of body temperature on the kinetic behavior of SPIONs in the liver by controlling body temperature using our temperature-control system. Second, we investigated the kinetic behavior of SPIONs in the liver when mice were injected with various doses of GdCl3, while keeping the body temperature at 36°C. Finally, we investigated it when mice were injected with various doses of zymosan, while keeping the body temperature at 36°C. We also investigated the effect of these substances on the number of Kupffer cells by immunohistochemical analysis using the specific surface antigen of Kupffer cells (CD68). To quantify the kinetic behavior of SPIONs in the liver, we calculated the upper limit of the relative enhancement (A), the rates of early contrast uptake (α) and washout or late contrast uptake (β), the parameter related to the slope of early uptake (q), the area under the curve (AUC), the maximum change of transverse relaxation rate (ΔR2) (ΔR2(max)), the time to ΔR2(max) (Tmax), and ΔR2 at the last time point (ΔR2(last)) from the time courses of ΔR2 using the EMM. The β and Tmax values significantly decreased and increased, respectively, with decreasing body temperature, suggesting that the phagocytic activity of Kupffer cells is significantly affected by body temperature. The AUC, ΔR2(max), and ΔR2(last) values decreased significantly with increasing dose of GdCl3, which was consistent with the change in the number of CD68-positive cells. They increased with increasing dose of zymosan, which was also consistent with the change in the number of CD68-positive cells. These results suggest that AUC, ΔR2(max), and ΔR2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999JSSCh.145..587L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999JSSCh.145..587L"><span>Spin Glass <span class="hlt">Magnetism</span> in the Oxygen-Rich La 2Co xCu 1- xO 4+ δ Layered Oxides: <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> and Muon-Spin-Relaxation Studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lappas, Alexandros; Prassides, Kosmas; Gygax, Fredy N.; Schenck, Alexander</p> <p>1999-07-01</p> <p>A series of oxygen-rich phases with formal stoichiometry La2CoxCu1-xO4+δ has been prepared. The excess of oxygen defects (0.06≤δ≤0.20) that can be accommodated in the structure is higher than that found in the parent superconducting La2CuO4+δ phase. The ac and dc <span class="hlt">susceptibility</span> measurements reveal a rich <span class="hlt">magnetic</span> phase diagram. The early members of the series (x≤0.25) order antiferromagnetically with localized <span class="hlt">magnetic</span> moments per ion site of 0.5 μB. The ordering temperature TN is rapidly reduced and the boundary of the paramagnetic-to-antiferromagnetic (AF) phase transition is smeared out as the cobalt content increases from x=0.25 to 0.5. Further increase of the cobalt content (0.5≤x≤0.90) leads to suppression of the AF state and the appearance of a spin glass at very low temperatures. This is attributed to the increased degree of structural and electronic disorder among (Co/Cu) sites, which leads to frustration of the nearest-neighbor (nn) AF bonds. The spin glass phases of the La2Co0.5Cu0.5O4.18 (Tf=18 K) and La2Co0.75Cu0.25O4.16 (Tf=30 K) were also investigated by the muon spin relaxation (μ+SR) technique. When Tf is approached from above, the μ+ spin dynamics show a nonexponential relaxation described by a power-law dependence of the muon spin polarization, G(t)=A0e-(λdt)β. The observed rapid growth of the correlation times τc is reminiscent of the spin freezing process in Ising spin glasses. A continuous drop in the value of the exponent β is also encountered, changing from 1.0 (simple exponential) at T∼3.3 Tf to 0.5 (square root exponential) at T∼1.3 Tf, and finally approaching 1/3 very close to Tf. A variety of chemical systems that undergo a spin glass transition are governed by spin dynamics that follow a universal picture similar to the one encountered here.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...12..146A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...12..146A"><span>The exceptional <span class="hlt">generalised</span> geometry of supersymmetric AdS flux backgrounds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ashmore, Anthony; Petrini, Michela; Waldram, Daniel</p> <p>2016-12-01</p> <p>We analyse generic AdS flux backgrounds preserving eight supercharges in D = 4 and D = 5 dimensions using exceptional <span class="hlt">generalised</span> geometry. We show that they are described by a pair of globally defined, <span class="hlt">generalised</span> structures, identical to those that appear for flat flux backgrounds but with different integrability conditions. We give a number of explicit examples of such "exceptional Sasaki-Einstein" backgrounds in type IIB supergravity and M-theory. In particular, we give the complete analysis of the generic AdS5 M-theory backgrounds. We also briefly discuss the structure of the moduli space of solutions. In all cases, one structure defines a "<span class="hlt">generalised</span> Reeb vector" that generates a Killing symmetry of the background corresponding to the R-symmetry of the dual field theory, and in addition encodes the generic contact structures that appear in the D = 4 M-theory and D = 5 type IIB cases. Finally, we investigate the relation between <span class="hlt">generalised</span> structures and quantities in the dual field theory, showing that the central charge and R-charge of BPS wrapped-brane states are both encoded by the <span class="hlt">generalised</span> Reeb vector, as well as discussing how volume minimisation (the dual of a- and F-maximisation) is encoded.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009PhDT.......302C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009PhDT.......302C"><span>Effets Josephson <span class="hlt">generalises</span> entre antiferroaimants et entre supraconducteurs antiferromagnetiques</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chasse, Dominique</p> <p></p> <p>L'effet Josephson est generalement presente comme le resultat de l'effet tunnel coherent de paires de Cooper a travers une jonction tunnel entre deux supraconducteurs, mais il est possible de l'expliquer dans un contexte plus general. Par exemple, Esposito & al. ont recemment demontre que l'effet Josephson DC peut etre decrit a l'aide du boson pseudo-Goldstone de deux systemes couples brisant chacun la symetrie abelienne U(1). Puisque cette description se <span class="hlt">generalise</span> de facon naturelle a des brisures de symetries continues non-abeliennes, l'equivalent de l'effet Josephson devrait donc exister pour des types d'ordre a longue portee differents de la supraconductivite. Le cas de deux ferroaimants itinerants (brisure de symetrie 0(3)) couples a travers une jonction tunnel a deja ete traite dans la litterature Afin de mettre en evidence la generalite du phenomene et dans le but de faire des predictions a partir d'un modele realiste, nous etudions le cas d'une jonction tunnel entre deux antiferroaimants itinerants. En adoptant une approche Similaire a celle d'Ambegaokar & Baratoff pour une jonction Josephson, nous trouvons un courant d'aimantation alternee a travers la jonction qui est proportionnel a sG x sD ou fG et sD sont les vecteurs de Neel de part et d'autre de la jonction. La fonction sinus caracteristique du courant Josephson standard est donc remplacee.ici par un produit vectoriel. Nous montrons que, d'un point de vue microscopique, ce phenomene resulte de l'effet tunnel coherent de paires particule-trou de spin 1 et de vecteur d'onde net egal au vecteur d'onde antiferromagnetique Q. Nous trouvons egalement la dependance en temperature de l'analogue du courant critique. En presence d'un champ magnetique externe, nous obtenons l'analogue de l'effet Josephson AC et la description complete que nous en donnons s'applique aussi au cas d'une jonction tunnel entre ferroaimants (dans ce dernier cas, les traitements anterieurs de cet effet AC s'averent incomplets). Nous</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27763692','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27763692"><span>Accelerated mapping of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> using 3D planes-on-a-paddlewheel (POP) EPI at ultra-high field strength.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stäb, Daniel; Bollmann, Steffen; Langkammer, Christian; Bredies, Kristian; Barth, Markus</p> <p>2017-04-01</p> <p>With the advent of ultra-high field MRI scanners in clinical research, <span class="hlt">susceptibility</span> based MRI has recently gained increasing interest because of its potential to assess subtle tissue changes underlying neurological pathologies/disorders. Conventional, but rather slow, three-dimensional (3D) spoiled gradient-echo (GRE) sequences are typically employed to assess the <span class="hlt">susceptibility</span> of tissue. 3D echo-planar imaging (EPI) represents a fast alternative but generally comes with echo-time restrictions, geometrical distortions and signal dropouts that can become severe at ultra-high fields. In this work we assess quantitative <span class="hlt">susceptibility</span> mapping (QSM) at 7 T using non-Cartesian 3D EPI with a planes-on-a-paddlewheel (POP) trajectory, which is created by rotating a standard EPI readout train around its own phase encoding axis. We show that the threefold accelerated non-Cartesian 3D POP EPI sequence enables very fast, whole brain <span class="hlt">susceptibility</span> mapping at an isotropic resolution of 1 mm and that the high image quality has sufficient signal-to-noise ratio in the phase data for reliable QSM processing. The <span class="hlt">susceptibility</span> maps obtained were comparable with regard to QSM values and geometric distortions to those calculated from a conventional 4 min 3D GRE scan using the same QSM processing pipeline. Copyright © 2016 John Wiley & Sons, Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990BVol...53...45M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990BVol...53...45M"><span>Flow directions in ash-flow tuffs: a comparison of geological and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> measurements, Tshirege member (upper Bandelier Tuff), Valles caldera, New Mexico, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Macdonadl, W. D.; Palmer, H. C.</p> <p>1990-12-01</p> <p>This study concludes that the elongation axis ( K 1) of the ellipsoid of anisotropic <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) is a suitable proxy for flow axis in ashflow tuffs. 153 oriented samples (176 specimens) were studied from 18 sites in the 1.1 Ma Tshirege member of the Bandelier Tuff. These sites are distributed around the Valles caldera at distances of 5 25 km outside of the rim. K 1 axes correlate well with postulated radial flow axes at 13 sites. K 1 also agrees with measured geological flow indicators, mainly imbricated larger clasts, at 7 sites. At 2 of the 5 sites where significant disagreement is seen between theoretical radial flow directions and measured K 1 axes, the K 1 axes correspond well with geological flow indicators, indicating that the divergence of flow from the predicted radial flow pattern is real. Two major topographic buttresses are suggested as the cause of flow divergence for the Tshirege ash flows: the San Pedro buttress northwest of the caldera, and the San Miguel buttress in the southeast. In situ K 1 axes plunge about 7° toward the source at two-thirds of the sites; therefore the plunge of K 1 is a plausible in situ indicator for the direction of flow. Multiple flow zones in sections of several meters thickness indicate changes of flow direction that are both rapid and large during ash-flow emplacement. These observations raisre the question of how best to represent ‘mean’ flow directions in ash-flow sheets: by eigenvector methods, by vector-sum methods, or by modes. A method for measuring imbrication of larger clasts using apparent dips in vertical joints is outlined. Imbrication, determined in this way at one-third of the sites, dips toward the source, i.e., up-flow. The minimum ( K 3) axis of the AMS ellipsoid correlates with the flow foliation rather than with the larger clast imbrication. The flow axes of ash flows correspond with the K 1 axes, not with the declination of K 3 axes as suggested by some authors. Initial dip of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ConSc..27..417C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ConSc..27..417C"><span>Promotion of cooperation in social dilemma games via <span class="hlt">generalised</span> indirect reciprocity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chiong, Raymond; Kirley, Michael</p> <p>2015-10-01</p> <p>This paper presents a novel <span class="hlt">generalised</span> indirect reciprocity approach for promoting cooperation in social dilemma games. Here, players decide upon an action to play in the game based on public information (or "external cues") rather than individual-specific information. The public information is constantly updated according to the underlying learning model. Comprehensive simulation experiments using the N-player Prisoner's Dilemma (PD) and Snowdrift (SD) games show that <span class="hlt">generalised</span> indirect reciprocity promotes high levels of cooperation across a wide range of conditions. This is despite the fact that the make-up of player groups is continually changing. As expected, the extent of cooperative behaviour observed in the "constraint-relaxed" N-player SD game is significantly higher than the N-player PD game. Our proposed <span class="hlt">generalised</span> indirect reciprocity model may shed light on the conundrum of cooperation between anonymous individuals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011IJC....84.1398B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011IJC....84.1398B"><span><span class="hlt">Generalised</span> tangential interpolation for model reduction of discrete-time MIMO bilinear systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Benner, P.; Breiten, T.; Damm, T.</p> <p>2011-08-01</p> <p>In this article, we discuss a model order reduction method for multiple-input and multiple-output discrete-time bilinear control systems. Similar to the continuous-time case, we will show that a system can be characterised by a series of <span class="hlt">generalised</span> transfer functions. This will be achieved by a multivariate Z-transform of kernels corresponding to an explicit solution formula for discrete-time systems. We will further address the problem of <span class="hlt">generalised</span> tangential interpolation which naturally comes along with this approach. We will introduce a reasonable <span class="hlt">generalisation</span> of the linear ℋ2-norm. Based on this concept, we discuss the choice of interpolation points. Furthermore, an efficient discretisation of continuous-time systems is provided. The performance of the proposed method is evaluated in some numerical examples and compared with the method of balanced truncation for bilinear systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26237652','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26237652"><span>Limited acquisition and <span class="hlt">generalisation</span> of rhotics with ultrasound visual feedback in childhood apraxia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Preston, Jonathan L; Maas, Edwin; Whittle, Jessica; Leece, Megan C; McCabe, Patricia</p> <p>2016-01-01</p> <p>Ultrasound visual feedback of the tongue is one treatment option for individuals with persisting speech sound errors. This study evaluated children's performance during acquisition and <span class="hlt">generalisation</span> of American English rhotics using ultrasound feedback. Three children aged 10-13 with persisting speech sound errors associated with childhood apraxia of speech (CAS) were treated for 14 one-hour sessions. Two of the participants increased the accuracy of their rhotic production during practise trials within treatment sessions, but none demonstrated <span class="hlt">generalisation</span> to untreated words. Lack of <span class="hlt">generalisation</span> may be due to a failure to acquire the target with sufficient accuracy during treatment, or to co-existing linguistic weaknesses that are not addressed in a motor-based treatment. Results suggest a need to refine the intervention procedures for CAS and/or a need to identify appropriate candidates for intervention to optimise learning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22659482','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22659482"><span>Quantitative <span class="hlt">susceptibility</span> mapping for investigating subtle <span class="hlt">susceptibility</span> variations in the human brain.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schweser, Ferdinand; Sommer, Karsten; Deistung, Andreas; Reichenbach, Jürgen Rainer</p> <p>2012-09-01</p> <p>Quantitative <span class="hlt">susceptibility</span> mapping (QSM) is a novel <span class="hlt">magnetic</span> resonance-based technique that determines tissue <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> from measurements of the <span class="hlt">magnetic</span> field perturbation. Due to the ill-posed nature of this problem, regularization strategies are generally required to reduce streaking artifacts on the computed maps. The present study introduces a new algorithm for calculating the <span class="hlt">susceptibility</span> distribution utilizing a priori information on its regional homogeneity derived from gradient echo phase images and analyzes the impact of erroneous a priori information on <span class="hlt">susceptibility</span> map fidelity. The algorithm, Homogeneity Enabled Incremental Dipole Inversion (HEIDI), was investigated with a special focus on the reconstruction of subtle <span class="hlt">susceptibility</span> variations in a numerical model and in volunteer data and was compared with two recently published approaches, Thresholded K-space Division (TKD) and Morphology Enabled Dipole Inversion (MEDI). HEIDI resulted in <span class="hlt">susceptibility</span> maps without streaking artifacts and excellent depiction of subtle <span class="hlt">susceptibility</span> variations in most regions. By investigating HEIDI <span class="hlt">susceptibility</span> maps acquired with the volunteers' heads in different orientations, it was demonstrated that the apparent <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> distribution of human brain tissue considerably depends on the direction of the main <span class="hlt">magnetic</span> field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15246952','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15246952"><span>Hypocalcemic <span class="hlt">generalised</span> seizures as a manifestation of iatrogenic hypoparathyroidism months to years after thyroid surgery.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mrowka, Matthias; Knake, Susanne; Klinge, Harald; Odin, Per; Rosenow, Felix</p> <p>2004-06-01</p> <p>Hypoparathyroidism is a relatively common side effect of a thyroidectomy and leads to hypocalcemia. Carpopedal spasm and tetany are typical manifestations and usually occur within weeks after surgery. The first signs can be less typical and include movement disorders such as chorea, as well as symptoms of increased intracranial pressure or epileptic seizures. We describe two cases with <span class="hlt">generalised</span> tonic-clonic seizures as the first manifestation of postoperative hypoparathyroidism, appearing months and years after thyroidectomy. Iatrogenic hypoparathyroidism needs to be considered in the differential diagnosis of adult-onset, <span class="hlt">generalised</span>, tonic-clonic seizures even if the thyroidectomy was performed years earlier.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJC....89.1169S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJC....89.1169S"><span>Global <span class="hlt">generalised</span> exponential/finite-time control for course-keeping of ships</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Xifang; Chen, Weisheng</p> <p>2016-06-01</p> <p>This paper addresses the global <span class="hlt">generalised</span> exponential/finite-time control of the nonlinear ship course system with an unknown control coefficient. Different from the well-known Nussbaum-gain adaptive rule, a new Lyapunov-based adaptive logic switching rule is proposed to seek the correct control direction of the ship course system. The main advantage of the proposed controller is that it guarantees the global <span class="hlt">generalised</span> exponential/finite-time control of closed-loop systems. Theoretical analysis and simulation results show the effectiveness of the developed control method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996PhyC..257...86R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996PhyC..257...86R"><span>NMR and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> in superconducting and antiferromagnetic Ga-based cuprates Y 1- xCa xSr 2Cu 2GaO 7 (0≤ x≤0.3)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rykov, Alexandre I.; Ueda, Yutaka; Goto, Atsushi; Yasuoka, Hiroshi</p> <p>1996-02-01</p> <p><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> and NMR/NQR measurements were performed on Y 1- xCa xSr 2Cu 2GaO 7 ( x=0, 0.1, 0.2, 0.3). The single phase samples annealed at 600°C under oxygen pressure of 30 MPa are superconductors with Tc=35 K for x=0.2 and x=0.3. In spite of the presence of a small Curie-like term, we show that the spin <span class="hlt">susceptibility</span> in the normal state increases with Ca doping and reaches the value χspin≈0.9 cm 3/Cu-mole, which is comparable to other superconducting cuprates. From the observation of Cu zero-field resonance (AFNR) and <span class="hlt">susceptibility</span> data the parent compound is classified as 2D antiferromagnet ( TN=387 K). The transition from antiferromagnetic insulator to superconductor occurs with increasing concentration of carriers, but extends over several tens percent of Ca. The superconductivity is significantly suppressed by increasing disorder within limits of solubility for Ca. The Ga NQR spectra are narrow in both antiferromagnetic and superconducting regimes, but heavily broadened in the intermediate spin-glass-like domain. From x=0 to x=0.3, the 63Cu quadrupole frequency increases from 24 to 28 MHz due to the charge transfer resulting in superconductivity. Other EFG parameters are not markedly changed from those given in YSr 2Cu 2GaO 7 by Pieper [Physica C190(1992)261].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1103504.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1103504.pdf"><span>Fostering Teacher Learning of Conjecturing, <span class="hlt">Generalising</span> and Justifying through Mathematics Studio</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Lesseig, Kristin</p> <p>2016-01-01</p> <p>Calls to advance students' ability to engage in mathematical reasoning practices including conjecturing, <span class="hlt">generalising</span> and justifying (CGJ) place significant new demands on teachers. This case study examines how Mathematics Studio provided opportunities for a team of U.S. middle school teachers to learn about these practices and ways to promote…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ914121.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ914121.pdf"><span>Modelling Problem-Solving Situations into Number Theory Tasks: The Route towards <span class="hlt">Generalisation</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Papadopoulos, Ioannis; Iatridou, Maria</p> <p>2010-01-01</p> <p>This paper examines the way two 10th graders cope with a non-standard <span class="hlt">generalisation</span> problem that involves elementary concepts of number theory (more specifically linear Diophantine equations) in the geometrical context of a rectangle's area. Emphasis is given on how the students' past experience of problem solving (expressed through interplay…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=photograph&pg=4&id=EJ1037024','ERIC'); return false;" href="http://eric.ed.gov/?q=photograph&pg=4&id=EJ1037024"><span>Brief Report: <span class="hlt">Generalisation</span> of Word-Picture Relations in Children with Autism and Typically Developing Children</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Hartley, Calum; Allen, Melissa L.</p> <p>2014-01-01</p> <p>We investigated whether low-functioning children with autism <span class="hlt">generalise</span> labels from colour photographs based on sameness of shape, colour, or both. Children with autism and language-matched controls were taught novel words paired with photographs of unfamiliar objects, and then sorted pictures and objects into two buckets according to whether or…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JAP....91.7637S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JAP....91.7637S"><span>Role of reversible <span class="hlt">susceptibility</span> in ferromagnetic hysteresis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schneider, Carl S.</p> <p>2002-05-01</p> <p>An equation of state based upon saturation <span class="hlt">magnetization</span>, Ms, coercive field, Hc, and the reversible <span class="hlt">susceptibility</span> function of <span class="hlt">magnetization</span> is proposed for ferromagnetic hysteresis. Reversible <span class="hlt">susceptibility</span> divided by the initial <span class="hlt">susceptibility</span> is the anisotropy function of <span class="hlt">magnetization</span>, χr, ranging from one in the demagnetized state to zero at saturation, and varying with <span class="hlt">magnetic</span> history. Its dependence on scaled <span class="hlt">magnetization</span>, m=M/Ms on the interval (-1,1) varies with material, allowing characterization of anisotropy classes. Precise measurements have been made of reversible <span class="hlt">susceptibility</span>, initial and saturate <span class="hlt">magnetization</span> curves, and loops for Orthonol™, annealed 3% nickel steel and as-received 1018 steel, representing crystals, isotropic polycrystals and composite ferromagnets, respectively. <span class="hlt">Magnetization</span> change is the product of the reversible <span class="hlt">susceptibility</span>, change in the applied field and the cooperative function due to domain interactions. This function is 1+βm for the virgin curve with half this slope from any reversal, where β=Ms/XiHc is the hysteresis coefficient. Variation of β for 1018 steel is due to distributed coercivities, and causes sigmoid B(H) curves. In the scaled field representation, where h=H/Hc, the cooperative function is 1/(1-hχr), a hyperbolic field dependence smeared by the anisotropy function. Constant anisotropy causes closed hysteresis loops, while variable anisotropy causes creeping of cycled asymmetric loops. In ferromagnetism, 1/χ=1/χr-h, normal scaled reluctivity is reduced from its reversible value by the scaled field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27326667','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27326667"><span>1,2,4-Diazaphospholide complexes of lanthanum(iii), cerium(iii), neodymium(iii), praseodymium(iii), and samarium(iii): synthesis, X-ray structural characterization, and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> studies.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhao, Minggang; Wang, Lixia; Li, Pangpang; Ma, Jianping; Zheng, Wenjun</p> <p>2016-07-05</p> <p>A few heteroleptic, charge-separated heterobimetallic, and polymeric alkali metalate complexes of 1,2,4-diazaphospholide lanthanum(iii), cerium(iii), neodymium(iii), praseodymium(iii), and samarium(iii) were simply prepared via the metathesis reaction of MCl3 (THF)m (m = 1-2) and K[3,5-R2dp] ([3,5-R2dp](-) = 3,5-di-substituent-1,2,4-diazaphospholide; R = tBu, Ph) in a varied ratio (1 : 3, 1 : 4, and 1 : 5, respectively) at room temperature in tetrahydrofuran. All the complexes were fully characterized by (1)H, (13)C{(1)H}, (31)P{(1)H}, IR, and X-ray single crystal diffraction analysis despite their paramagnetism (excluding La(iii) complexes). The structures of the complexes were found to feature varied coordination modes. The <span class="hlt">magnetic</span> properties of several compounds were studied by <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, and the complexes presented the <span class="hlt">magnetic</span> moments close to or lower than the theoretical values for the free ions in the trivalent oxidation states (Pr(3+), Nd(3+)).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/4284269','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/4284269"><span><span class="hlt">MAGNETS</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Hofacker, H.B.</p> <p>1958-09-23</p> <p>This patent relates to nmgnets used in a calutron and more particularly to means fur clamping an assembly of <span class="hlt">magnet</span> coils and coil spacers into tightly assembled relation in a fluid-tight vessel. The <span class="hlt">magnet</span> comprises windings made up of an assembly of alternate pan-cake type coils and spacers disposed in a fluid-tight vessel. At one end of the tank a plurality of clamping strips are held firmly against the assembly by adjustable bolts extending through the adjacent wall. The foregoing arrangement permits taking up any looseness which may develop in the assembly of coils and spacers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015OptCo.335..126J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015OptCo.335..126J"><span>Harmonic undulator radiations with constant <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jeevakhan, Hussain; Mishra, G.</p> <p>2015-01-01</p> <p>Harmonic undulators has been analysed in the presence of constant <span class="hlt">magnetic</span> field along the direction of main undulator field. The spectrum modifications in harmonic undulator radiations and intensity degradation as a function of constant <span class="hlt">magnetic</span> field magnitude at fundamental and third harmonics have been evaluated with a numerical integration method and <span class="hlt">generalised</span> Bessel function. The role of harmonic field to overcome the intensity reduction due to constant <span class="hlt">magnetic</span> field and energy spread in electron beam has also been demonstrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JPhCS.400c2122Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JPhCS.400c2122Y"><span><span class="hlt">Magnetic</span> <span class="hlt">susceptibility</span> investigation of Bose-glass state in Ni0.85Cd0.15Cl2-4SC(NH2)2 at ultra-low temperatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yin, L.; Xia, J. S.; Sullivan, N. S.; Zapf, V. S.; Paduan-Filho, A.; Yu, R.; Roscilde, T.</p> <p>2012-12-01</p> <p>We report measurements of the AC <span class="hlt">susceptibility</span> of a site-diluted quantum <span class="hlt">magnet</span> Ni0.85Cd0.15Cl2-4SC(NH2)2 (15% Cd-doped dichloro-tetrakis-thiourea-Nickel, or Cd-DTN) down to 10 mK Below a crossover temperature Tcr ≍ 100 ~ 200mK, we find that the critical fields Hc for Bose-Einstein condensation obey the scaling relation |Hc(T)-Hc(0)| ~ Tα, with a novel and universal scaling exponent α ≍ 0.9, which is in agreement with numerical results from a theoretical model. Our findings provide strong evidence of the existence of a Bose glass phase in Cd-DTN, and they display a quantitative signature of the transition between a Bose glass and a Bose Einstein condensate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Diamagnetic&id=EJ187550','ERIC'); return false;" href="http://eric.ed.gov/?q=Diamagnetic&id=EJ187550"><span>Experiments on <span class="hlt">Magnetic</span> Materials</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Schneider, C. S.; Ertel, John P.</p> <p>1978-01-01</p> <p>Describes the construction and use of a simple apparatus to measure the <span class="hlt">magnetization</span> density and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> of ferromagnetic, paramagnetic, and the diamagnetic solids and liquids. (Author/GA)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGP41C1139K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGP41C1139K"><span>A Systematic Comparison of Anisotropy of <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> (AMS) and Anisotropy of Remanence (AARM) fabrics of ignimbrites: Examples from the Gold Point area, Nevada and Jemez Mountains, New Mexico</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kharwat, R.; Geissman, J. W.; Fitter, T.</p> <p>2013-12-01</p> <p>Anisotropy of <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> (AMS) has been widely used to define petrofabrics in silicic, elevated-temperature pyroclastic deposits (i.e. ignimbrites) and have successfully identified pyroclastic emplacement or transport directions in many cases. Anisotropy of remanence studies, which are more time-consuming, are far less commonly used to evaluate ignimbrite fabrics. As part of a broad study to understand the Neogene history of deformation associated with a transfer system in the western Great Basin paleomagnetic and <span class="hlt">magnetic</span> fabric data have been collected from ignimbrites that originated from the Timber Mountain Caldera complex, active from 14-11.5 Ma. A subset of this collection, as well as the Quaternary Bandelier Tuff, exposed in the Jemez Mountains, New Mexico, have been studied in order to systematically compare anisotropy of remanence (mainly anhysteretic remanent <span class="hlt">magnetization</span>, AARM) with AMS data from the same sites. The relationship between AMS and anisotropy of remanence fabrics in these rocks offers insight into which approach provides data that are more indicative of actual emplacement related fabrics and a measure of anisotropy. AARM data can be advantageous when compared to AMS results, as remanence is typically more sensitive to mineral grains with higher degree of anisotropies (i.e. ferro/ferrimagnetic minerals). Here, AMS and AARM are compared for 15 (9-10 samples per site) sites in western Nevada ignimbrites, and several sites in the Bandelier Tuff (in progress), with each chosen to examine the effects of varying degrees of welding and crystal content on the fabrics obtained. The average bulk <span class="hlt">susceptibility</span> for the Nevada sites is 4.38 x 10-03 (SI volume), indicating that magnetite is the dominant contributor. AMS imbrication fabric data for these sites typically show a northwest transport direction, which is consistent with the source. The Degree of anisotropy for AARM data ranges from 1.04 to 2.24 for Nevada sites. The relationships</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003CP....293..375B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003CP....293..375B"><span>Spin crossover in iron(II) tris(2-(2 '-pyridyl)benzimidazole) complex monitored by variable temperature methods: synchrotron powder diffraction, DSC, IR spectra, Mössbauer spectra, and <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boča, R.; Boča, M.; Ehrenberg, H.; Fuess, H.; Linert, W.; Renz, F.; Svoboda, I.</p> <p>2003-09-01</p> <p>The thermal expansion of the spin crossover system [Fe(pybzim) 3](ClO 4) 2 · H 2O (pybzim=2-(2 '-pyridyl)benzimidazole) has been determined from powder X-ray data between 50 and 250 K; the wavelength of the synchrotron source was 1.21888(1) Å. The unit cell parameters of the triclinic crystal system were a=12.091 Å, b=12.225 Å, c=14.083 Å, α=77.70°, β=80.35°, γ=74.35°, and V=1944.9 Å 3 at 250 K. In addition to the linear thermal expansion of the unit cell volume, an extra expansion due to the low-spin (LS) to high-spin (HS) transition is observed. The V( T) function shows a sudden increase comparable with the step in the effective <span class="hlt">magnetic</span> moment at the transition region (140 K). A similar behavior is obtained on the basis of the infrared spectra. The absorption bands corresponding to the metal-ligand stretching modes change their intensities upon heating: the bands corresponding to the low-spin molecules (at ca. 409, 430, 443, and 460 cm -1) disappear in the gain of the high-spin bands (at 259 and 285 cm -1). The variable-temperature data obtained by different techniques (powder diffraction, EXAFS, IR spectra, Mössbauer spectra, <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span>, DSC) have been transformed to a common basis - the temperature dependence of the high-spin mole fraction xHS( T). The application of the Ising-like (two-level) model of the spin crossover led to the thermodynamic data Δ H=2.6 kJ mol -1 and Δ S=19 J K -1 mol -1 as well as to the cooperativeness J/ k≈110 K (subtracted from the <span class="hlt">susceptibility</span> data) that characterizes the abruptness of the spin crossover in the solid state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012IJTP...51.1621M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012IJTP...51.1621M"><span>The Effect of the Number of Simulations on the Exponents Obtained by Finite-Size Scaling Relations of the Order Parameter and the <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> for the Four-Dimensional Ising Model on the Creutz Cellular Automaton</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Merdan, Z.; Güzelsoy, E.</p> <p>2012-05-01</p> <p>The four-dimensional Ising model is simulated on the Creutz cellular automaton using finite-size lattices with linear dimension 4≤ L≤8. The exponents in the finite-size scaling relations for the order parameter and the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> at the finite-lattice critical temperature are computed to be β=0.49(7), β=0.49(5), β=0.50(1) and γ=1.04(4), γ=1.03(4), γ=1.02(4) for 7, 14, and 21 independent simulations, respectively. As the number of independent simulations increases, the obtained results are consistent with the renormalization group predictions of β=0.5 and γ=1. The values for the critical temperature of the infinite lattice T c (∞)=6.6788(65), T c (∞)=6.6798(69), T c (∞)=6.6802(70) are obtained from the straight-line fit of the <span class="hlt">magnetic</span> <span class="hlt">susceptibility</span> maxima using 4≤ L≤8 for 7, 14, and 21 independent simulations, respectively. As the number of independent simulations increases, the obtained results are in very good agreement with the series expansion results of T c (∞)=6.6817(15), T c (∞)=6.6802(2), the dynamic Monte Carlo result of T c (∞)=6.6803(1), the cluster Monte Carlo result of T c (∞)=6.680(1) and the Monte Carlo using Metropolis and Wolff-cluster algorithm result of T c (∞)=6.6802632±5×10-5.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2685219','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2685219"><span>Synthetic antiferromagnetic nanoparticles with tunable <span class="hlt">susceptibilities</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hu, Wei; Wilson, Robert J.; Earhart, Christopher M.; Koh, Ai Leen; Sinclair, Robert; Wang, Shan X.</p> <p>2009-01-01</p> <p>High-moment monodisperse disk-shaped Co–Fe <span class="hlt">magnetic</span> nanoparticles, stable in aqueous solution, were physically fabricated by using nanoimprinted templates and vacuum deposition techniques. These multilayer synthetic antiferromagnetic nanoparticles exhibit nearly zero <span class="hlt">magnetic</span> remanence and coercivity, and <span class="hlt">susceptibilities</span> which can be tuned by exploiting interlayer <span class="hlt">magnetic</span> interactions. In addition, a low cost method of scaling up the production of sub-100 nm synthetic antiferromagnetic nanoparticles is demonstrated. PMID:19529797</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA223609','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA223609"><span>Sigma and Pi Interactions of the Pyrrolic Ligand Sandwich-Like Lanthanide Phthalocyanines Determined from <span class="hlt">Magnetic</span> <span class="hlt">Susceptibility</span> and Ligand-Field Theory</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>1990-06-25</p> <p>ACCESSION NO. 11, TITLE (include Security Classification) UNCLASSIFIED: Sigma and Pi Interactions of the Pyrro- lic Ligand Sandwich-Like Lanthanide ...4135007---05 TECHNICAL REPORT NO. 36 Sigma and Pi Interactions of the Pyrrolic Ligand Sandwich-Like Lanthanide Phthalocyanines Determined From <span class="hlt">Magnetic</span>...Hill Chapel Hill, North Carolina 27599-3290 Sigma and Pi Interactions of the Pyrrolic Ligand Sandwich-Like Lanthanide Phthalocyanines Determined From</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22314815','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22314815"><span><span class="hlt">Generalised</span> BRST symmetry and gaugeon formalism for perturbative quantum gravity: Novel observation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Upadhyay, Sudhaker</p> <p>2014-05-15</p> <p>In this paper the novel features of Yokoyama gaugeon formalism are stressed out for the theory of perturbative quantum gravity in the Einstein curved spacetime. The quantum gauge transformations for the theory of perturbative gravity are demonstrated in the framework of gaugeon formalism. These quantum gauge transformations lead to renormalised gauge parameter. Further, we analyse the BRST symmetric gaugeon formalism which embeds more acceptable Kugo–Ojima subsidiary condition. Further, the BRST symmetry is made finite and field-dependent. Remarkably, the Jacobian of path integral under finite and field-dependent BRST symmetry amounts to the exact gaugeon action in the effective theory of perturbative quantum gravity. -- Highlights: •We analyse the perturbative gravity in gaugeon formalism. •The <span class="hlt">generalisation</span> of BRST transformation is also studied in this context. •Within the <span class="hlt">generalised</span> BRST framework we found the exact gaugeon modes in the theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005EL.....71..339D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005EL.....71..339D"><span>On the emergence of a <span class="hlt">generalised</span> Gamma distribution. Application to traded volume in financial markets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duarte Queirós, S. M.</p> <p>2005-08-01</p> <p>This letter reports on a stochastic dynamical scenario whose associated stationary probability density function is exactly a <span class="hlt">generalised</span> form, with a power law instead of exponencial decay, of the ubiquitous Gamma distribution. This <span class="hlt">generalisation</span>, also known as F-distribution, was empirically proposed for the first time to adjust for high-frequency stock traded volume distributions in financial markets and verified in experiments with granular material. The dynamical assumption presented herein is based on local temporal fluctuations of the average value of the observable under study. This proposal is related to superstatistics and thus to the current nonextensive statistical mechanics framework. For the specific case of stock traded volume, we connect the local fluctuations in the mean stock traded volume with the typical herding behaviour presented by financial traders. Last of all, NASDAQ 1 and 2 minute stock traded volume sequences and probability density functions are numerically reproduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12140123','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12140123"><span>A preliminary study of dopamine-mediated prolactin inhibition in <span class="hlt">generalised</span> social phobia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Condren, Rita M; Sharifi, Neda; Thakore, Jogin H</p> <p>2002-08-05</p> <p>The biology of social phobia has been little studied, but a possible role for dopamine has been implicated in this disorder. The aim of this study was to examine central dopaminergic function in patients with <span class="hlt">generalised</span> social phobia using the prolactin response to quinagolide, a dopamine D2 receptor agonist, and to compare responses with those of normal controls. The study included 14 patients with moderate or severe <span class="hlt">generalised</span> social phobia and 14 healthy age- and gender-matched comparison subjects. Quinagolide (0.5 mg) was administered orally and prolactin responses were measured over 4 h. There was no significant difference between prolactin responses in patients and healthy controls, nor was there a correlation between prolactin response and age, sex, or severity of illness. This would suggest that tuberoinfundibular dopamine D2 receptor sensitivity is normal in this disorder.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23050500','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23050500"><span>Does our research tool kit equip us to make <span class="hlt">generalisable</span> claims about dental education?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chambers, D W</p> <p>2012-11-01</p> <p