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See detailMagnetic ordering in U2Pd2In and U2Pd2Sn
Purwanto, A.; Robinson, R. A.; Havela, Ladislav et al

in Physical Review. B : Condensed Matter (1994), 50(10), 6792-6801

The tetragonal intermetallic compounds U2Pd2In and U2Pd2Sn have been studied by means of magnetic susceptibility, magnetization, specific heat, electrical resistivity, and x-ray- and neutron-diffraction ... [more ▼]

The tetragonal intermetallic compounds U2Pd2In and U2Pd2Sn have been studied by means of magnetic susceptibility, magnetization, specific heat, electrical resistivity, and x-ray- and neutron-diffraction techniques. The compounds order antiferromagnetically at 36 and 41 K, respectively, and have enhanced electronic specific-heat coefficients γ of 393 and 203 mJ/mol f.u. K**2, respectively. At low temperature, the nearest-neighbor U-U spacing is along the c axis in both compounds, though in U2Pd2Sn the in-plane U-U distance is shorter at room temperature. This crossover is due to motion of the U atoms within the cell rather than anisotropy of the thermal contraction. It is now well established in several classes of (1:1:1) uranium ternary intermetallic compounds that the strong magnetic anisotropy is correlated with the direction of nearest-neighbor U-U links; the moments are almost invariably oriented perpendicular to such links. This is also the case for U2Pd2In and U2Pd2Sn, where the moments lie in the tetragonal basal plane in a canted arrangement along [110] and [1¯10] directions. Of four such Shubnikov subgroups of P4/mbm, one is clearly preferred by the data. At 10 K, the magnetic moments extracted are (1.6±0.2) Bohr magneton and (2.0±0.1) Bohr magneton per U atom in U2Pd2In and U2Pd2Sn, respectively. [less ▲]

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See detailMagnetic ordering in U2Pd2Sn and U2Pd2In
Ladislav, Havela; Svoboda, P.; Purwanto, A. et al

Conference (1994, April)

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See detailMagnetic properties and anisotropy of orthorhombic DyMnO3 single crystal
Pękała, M.; Wolff-Fabris, F.; Fagnard, Jean-François ULg et al

in Journal of Magnetism and Magnetic Materials (2013), 335(0), 46-52

An orthorhombic DyMnO3 single crystal has been studied in magnetic fields up to 14 T and between 3 K and room temperature. The field dependent ordering temperature of Dy moments is deduced. The ... [more ▼]

An orthorhombic DyMnO3 single crystal has been studied in magnetic fields up to 14 T and between 3 K and room temperature. The field dependent ordering temperature of Dy moments is deduced. The paramagnetic Curie Weiss behavior is related mainly to the Dy3+sublattice whereas the Mn sublattice contribution plays a secondary role. DC magnetization measurements show marked anisotropic features, related to the anisotropic structure of a cubic system stretched along a body diagonal, with a magnetic easy axis parallel to the crystallographic b axis. A temperature and field dependent spin flop transition is observed below 9 K, when relatively weak magnetocrystalline anisotropy is overcome by magnetic fields up to 1.6 T. [less ▲]

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See detailMagnetic properties of drilled bulk high-temperature superconductors filled with a ferromagnetic powder
Lousberg, Grégory; Fagnard, Jean-François ULg; Chaud, Xavier et al

in Superconductor Science and Technology (2011), 24

It is shown that filling the holes of a drilled bulk high-temperature superconductor (HTS) with a soft ferromagnetic powder enhances its trapping properties. The magnetic properties of the trapped field ... [more ▼]

It is shown that filling the holes of a drilled bulk high-temperature superconductor (HTS) with a soft ferromagnetic powder enhances its trapping properties. The magnetic properties of the trapped field magnet are characterized by Hall probe mapping and magnetization measurements. This analysis is completed by a numerical model based on a 3D finite-element method where the conductivity of the superconducting material is described by a power law while the permeability of the ferromagnetic material is fixed to a given value and is considered uniform. Numerical results support the experimental observations. In particular, they confirm the increase of trapped flux that is observed with Hall probe mapping after impregnation. [less ▲]

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See detailMagnetic Properties of Fe2GeMo3N; an Experimental and Computational Study
Battle, Peter; Sviridov, L.A.; Woolley, R. J. et al

in Journal of Materials Chemistry (2012), 22

A polycrystalline sample of Fe2GeMo3N has been synthesized by the reductive nitridation of a mixture of binary oxides in a flow of 10% dihydrogen in dinitrogen. The reaction product has been studied by ... [more ▼]

A polycrystalline sample of Fe2GeMo3N has been synthesized by the reductive nitridation of a mixture of binary oxides in a flow of 10% dihydrogen in dinitrogen. The reaction product has been studied by magnetometry, neutron diffraction and M€ossbauer spectroscopy over the temperature range 1.8 # T/K # 700. The electronic properties have been modelled by DFT and Monte Carlo methods. Fe2GeMo3N adopts the cubic h-carbide structure with a ¼ 11.1630(1) at 300 K. The electrical conductivity was found to be 0.9 mU cm over the temperature range 80 # T/K # 300. On cooling below 455 K the compound undergoes a transition to an antiferromagnetic state. The magnetic unit cell contains an antiferromagnetic arrangement of eight ferromagnetic Fe4 tetrahedra; the ordered atomic magnetic moments, 1.90(4) mB per Fe atom at 1.8 K, align along a <111> direction. DFT predicts an ordered moment of 1.831 mB per Fe, albeit with a N eel temperature of >549 K. Monte Carlo calculations confirm that the experimentally determined magnetic structure is the lowest-energy antiferromagnetic structure. These results emphasise the potential of these computational methods in the search for new magnetic materials. [less ▲]

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See detailMagnetic properties of Ga-doped lanthanum manganite with controlled oxygen stoichometry
Vertruyen, Bénédicte ULg; Hebert, Sylvie; Maignan, Antoine et al

in Crystal Engineering (2002), 5

Stoichiometric LaMnO3 is an insulator whose A-type antiferromagnetic structure at low temperature is mainly connected to the Jahn-Teller distortion of the MnO6 octahedra. The substitution of non magnetic ... [more ▼]

Stoichiometric LaMnO3 is an insulator whose A-type antiferromagnetic structure at low temperature is mainly connected to the Jahn-Teller distortion of the MnO6 octahedra. The substitution of non magnetic d(10) Ga3+ ions on the manganese site disrupts the orbital and spin orderings of the manganese ions and has a strong influence on the physical properties. The antiferromagnetic order is progressively destroyed while the ferromagnetic component increases. At the same time, the distortion of the orthorhombic cell decreases and the high temperature structural Jahn-Teller transition disappears. Such studies on manganese site substitutions give insight into the physics of the Mn-O three-dimensional network, which is supposed to be the key feature in the CMR manganites. (C) 2003 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailMagnetic properties of iron nitride-alumina nanocomposite materials prepared by high-energy ball milling
Mishra, S. R.; Long, G. J.; Grandjean, Fernande ULg et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2003), 24(1-3), 93-96

The structural and magnetic properties of the granular iron nitride-alumina composite materials: (FexN)(0.2)(Al2O3)(0.8) and (FexN)(0.6)(Al2O3)(0.4), fabricated using high-energy ball milling have been ... [more ▼]

The structural and magnetic properties of the granular iron nitride-alumina composite materials: (FexN)(0.2)(Al2O3)(0.8) and (FexN)(0.6)(Al2O3)(0.4), fabricated using high-energy ball milling have been determined by using X-ray diffraction, Mossbauer spectroscopy, and magnetization measurements. The Mossbauer spectra, fit with a distribution of hyperfine fields between zero and 40 T. indicate that the weighted average field decreases with increasing milling time. The isomer shift increases with milling time because of a reduced iron 4s-electron density at the grain boundaries. Coercive fields as high as 325 and 110 Oe are obtained for (FexN)(0.2)(Al2O3)(0.8) at 5 and 300 K, respectively; the increase in the coercive field upon cooling indicates the presence of superparamagnetic particles. The coercive field increases with milling time because of the reduced particle size. The decrease in the magnetization results from the increase in both the superparamagnetic fraction and the concentration of surface defects with increased milling time. [less ▲]

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See detailMagnetic properties of magnetically textured Bi-2212 ceramics
Vanderbemden, Philippe ULg; Bougrine, Hassan ULg; Ausloos, Marcel ULg et al

in Physica C: Superconductivity (2001), 351(1), 67-70

This paper aims at reporting magnetic properties of bulk polycrystalline Bi2Sr2Ca0.8Dy0.2Cu2O8-y samples textured under a magnetic field. The microstructure of these materials is highly anisotropic and ... [more ▼]

This paper aims at reporting magnetic properties of bulk polycrystalline Bi2Sr2Ca0.8Dy0.2Cu2O8-y samples textured under a magnetic field. The microstructure of these materials is highly anisotropic and exhibits particular features needed to be taken into account in order to interpret their magnetic and electrical properties. First the AC magnetic susceptibility has been measured for several magnetic fields (H parallel to ab and H parallel to c) and compared to the electrical resistivity data. The structure of the chi'' peak is shown to be related to the chemical content distribution of the superconducting grains. Next, the magnetic flux profiles have been extracted from the magnetic measurements using the Campbell-Rollins procedure. The anisotropy of the flux profiles and their peculiar curvature behaviour for H parallel toc point out the role of both grain platelet structure and the presence of secondary phases. From these results, we conclude that the magnetic properties of such magnetically textured materials do not allow for a reliable extraction of the critical current density J(c) but essentially probe geometric effects. Such effects have to be taken into account for improving the manufacture of attractive high-T-c materials. (C) 2001 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailMagnetic properties of melt-textured DyBCO single domains
Vanderbemden, Philippe ULg; Ausloos, Marcel ULg; Cloots, Rudi ULg

in Materials Research Society Symposium Proceedings (2001), 659

This communication aims at reporting the superconducting properties of several bulk melt-processed DyBa2Cu3O7-x samples determined by using various measuring techniques. The original single domain ... [more ▼]

This communication aims at reporting the superconducting properties of several bulk melt-processed DyBa2Cu3O7-x samples determined by using various measuring techniques. The original single domain material was first cut into 9 similar cubic samples which have been characterized by AC susceptibility, flux profiles and DC magnetization. The results indicate good quality melt-processed (RE)BCO materials with Tc = 89 K. Next, the effect of post oxygen annealing treatments on these samples was studied. The influence of the non-uniformity of the oxygen content on the magnetic property anisotropy is discussed. Finally, additional magnetic measurements were carried out by using a couple of parallel pick-up coils wound on the same sample. From the results we conclude that geometric effects have to be taken into account in order to extract the critical current density from the magnetic properties. [less ▲]

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See detailMagnetic properties of nanosized MgFe2O4 powders prepared by auto-combustion
Ghelev, Ch; Koutzarova, T.; Kolev, S. et al

in Journal of Physics: Conference Series (2012), 356(1), 012048

Targets were prepared to be used for magnetron sputtering and laser ablation and their microstructural and magnetic properties were investigated. The base material was nanosized MgFe2O4 powder produced by ... [more ▼]

Targets were prepared to be used for magnetron sputtering and laser ablation and their microstructural and magnetic properties were investigated. The base material was nanosized MgFe2O4 powder produced by citrate auto-combustion synthesis. The auto-combusted powders were annealed at temperatures in the range 600 - 1000°C in air to study the effect of temperature on thofe formation MgFe2O4. The saturation magnetization Ms was 24.30 emu/g at room temperature. © Published under licence by IOP Publishing Ltd. [less ▲]

Detailed reference viewed: 53 (3 ULg)
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See detailMagnetic properties of Np2T2Sn compounds
Sanchez, Jean-Pierre; Colineau, E.; Jeandey, C. et al

in Physica B: Condensed Matter (1995), 206 & 207

The magnetic properties of the Np2T2Sn series investigated by 237Np Mössbauer spectroscopy are reported. Magnetic ordering is shown to occur for T --- Ni, Pd, Pt, whereas the Np ions do not carry a local ... [more ▼]

The magnetic properties of the Np2T2Sn series investigated by 237Np Mössbauer spectroscopy are reported. Magnetic ordering is shown to occur for T --- Ni, Pd, Pt, whereas the Np ions do not carry a local moment when T --- Co, Ru, Rh. Comparisons are made with the corresponding Np2T2In and U2T2Sn compounds. [less ▲]

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See detailMagnetic properties of U2T2X compounds
Havela, Ladislav; Sechovsky, Vladimir; Nakotte, Heinz et al

Poster (1993, April)

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See detailMagnetic resonance arthrography of cubital joint in dogs affected with fragmented medial coronoid process
Snaps, Frédéric ULg; Park, R. D.; Saunders, J. et al

in American Journal of Veterinary Research (1999), 20

Objective-To evaluate efficacy of intra-articular injection of gadolinium tetra- azacyclododecane tetraacetic acid (gadolinium-DOTA) for delineating fragmented medial coronoid processes (FMCP) and lesions ... [more ▼]

Objective-To evaluate efficacy of intra-articular injection of gadolinium tetra- azacyclododecane tetraacetic acid (gadolinium-DOTA) for delineating fragmented medial coronoid processes (FMCP) and lesions on the medial aspect of the humeral condyle (MAHC). Sample Population-14 cubital joints in 9 dogs. Procedure-Magnetic resonance imaging (MRI) was performed with and without intra-articular injection of a solution of 2 mmol of gadolinium-DOTA/L. Arthrographic images obtained after injection of contrast medium were compared with those obtained without contrast medium. Evidence of contrast medium around or in the medial coronoid process and infiltration of contrast medium in subchondral bone lesions was recorded, Twenty-four hours after imaging, arthroscopy was performed, and lesions detected were correlated with results of MRI. Results-An abnormal coronoid process was diagnosed in 13 of 14 joints. A fragmented process (free) was seen in 7 of 14 joints; nondisplaced mineralized medial tin situ) coronoid processes were evident in 4 joints; and nondisplaced unmineralized medial coronoid processes were evident in 2 joints. Lesions on the MAHC were diagnosed in 4 of 12 joints. In 5 joints, a hyperintense signal resulted from contrast medium that infiltrated between the fragmented process and ulna. In 2 joints, contrast medium did not infiltrate completely around the process and was stopped by an isointense structure tie, abnormal cartilage). Subchondral bone lesions were enhanced by use of contrast medium. Conclusion and Clinical Relevance-Use of arthrography enabled us to identify FMCP easily, but did not provide important additional information about changes on the medial coronoid process, compared with MRI performed without contrast medium. [less ▲]

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See detailMagnetic Resonance Imaging and biochemical markers of osteoarthritis of the knee
Kothari, Manish; Bruyère, Olivier ULg; COLLETTE, Julien ULg et al

in Arthritis and Rheumatism (2005, September), 52(number 9 (suppl.)), 71

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Peer Reviewed
See detailA magnetic resonance imaging approach for the diagnosis of a triplet cornual pregnancy.
Bassil, Salim; Gordts, Stéphane; NISOLLE, Michelle ULg et al

in Fertility and Sterility (1995), 64(5), 1029-31

Objectives: To describe a rare case of triplet cornual pregnancy after IVF-ET and to assess the role of magnetic resonance imaging (MRI) for early diagnosis. DESIGN: Case report. SETTING: Infertility and ... [more ▼]

Objectives: To describe a rare case of triplet cornual pregnancy after IVF-ET and to assess the role of magnetic resonance imaging (MRI) for early diagnosis. DESIGN: Case report. SETTING: Infertility and IVF Unit, in an university medical center. PATIENT: A 31-year-old healthy patient with a 3-year history of primary male infertility. INTERVENTION: Standard IVF-ET treatment cycle, using a GnRH-agonist (long protocol) and hMG for ovarian stimulation. RESULTS: A cornual triplet pregnancy is described with the approach for the diagnosis. Magnetic resonance imaging was complementary to endovaginal sonography for early diagnosis and permitted a timed conservative management. CONCLUSIONS: When transvaginal ultrasound findings did not provide an accurate location of the pregnancy, MRI was indicated to confirm the diagnosis. [less ▲]

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See detailMagnetic resonance imaging arteriography of canine normal brain: an anatomic study
Jacqmot, Olivier ULg; Hoffmann, A. C.; Bustin, P. H. et al

Poster (2008)

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See detailMagnetic resonance imaging findings in the equine deep digital flexor tendon and distal sesamoid bone in advanced navicular disease--an ex vivo study.
Busoni, Valeria ULg; Heimann, Marianne; Trenteseaux, Jacques ULg et al

in Veterinary Radiology & Ultrasound (2005), 46(4), 279-86

We describe the abnormal magnetic resonance (MR) imaging findings in the deep digital flexor tendon (DDFT) and distal sesamoid bone in horses with radiographic changes compatible with navicular syndrome ... [more ▼]

We describe the abnormal magnetic resonance (MR) imaging findings in the deep digital flexor tendon (DDFT) and distal sesamoid bone in horses with radiographic changes compatible with navicular syndrome. Thirteen postmortem specimens were examined using a 1.5-T magnetic field, with spin echo (SE) T1-weighted, turbo SE (TSE) proton density-weighted (with and without fat saturation), and fat saturation TSE T2-weighted sequences. The limbs were then dissected to compare the MR findings with the gross assessment and histologic examination of the DDFT and distal sesamoid bones. Tendonous abnormalities were detected by MR imaging in 12 DDFTs and confirmed at necropsy. Most tendon lesions were located at the level of the distal sesamoid bone and the proximal recess of the podotrochlear bursa. Tendon lesions were classified based on their MR imaging features as core lesions, dorsal lesions, dorsal abrasions, and parasagittal splits. Areas of increased MR signal in the DDFTs were characterized by tendon fiber disturbance and lack of continuity of the collagen fibers, foci of edema, hemorrhages, and formation of lakes containing eosinophilic plasma-like material or amphophilic material of low density. Bone marrow signal alterations in the distal sesamoid bone were seen in all digits. Two main phenomena were responsible for the abnormal signal, respectively, in T1-weighted (decreased signal) and in T2-weighted fat-suppressed images (increased signal): a decrease in the fat marrow content in the trabecular spaces and an increase in the fluid content. Histologic examination revealed foci of bone marrow edema, hemorrhage, necrosis, and fibrosis. Cyst formation and trabecular abnormalities (disorganization, thinning, remodelling) were also observed in areas of abnormal signal intensity. Increased bone density because of trabecular thickening induced a decrease in signal in all sequences. [less ▲]

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See detailMagnetic resonance imaging of canine elbow joint
Saunders; Snaps, Frédéric ULg

Conference (2006)

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See detailMagnetic resonance imaging of the palmar aspect of the equine podotrochlear apparatus: Normal appearance
Busoni, Valeria ULg; Snaps, Frédéric ULg; Trenteseaux, Jacques ULg et al

in Veterinary Radiology & Ultrasound (2004), 45(3), 198-204

The purpose of this study was to describe the normal magnetic resonance (MR) imaging characteristics of the palmar structures of the equine podotrochlear apparatus by means of retrospective evaluation of ... [more ▼]

The purpose of this study was to describe the normal magnetic resonance (MR) imaging characteristics of the palmar structures of the equine podotrochlear apparatus by means of retrospective evaluation of MR imaging studies of 16 cadaver limbs. The articular aspect of the distal sesamoid bone was not evaluated in this study. Equine digits were imaged with a human knee radiofrequency coil in a 1.5 T magnetic field, using spin echo (SE) T1-weighted, turbo spin echo proton density (TSE PD)-weighted with and without fat saturation (FS), and FS TSE T2-weighted sequences. The limbs were dissected after imaging to validate the absence of gross abnormalities of the flexor aspect of the distal sesamoid bone, of the deep digital flexor tendon, and the distal impar sesamoidean ligament. Seven deep digital flexor tendons were subjected to histologic examination to exclude any microscopic tendon pathology. The anatomic structures of the podotrochlear apparatus were easily identified on MR images. Compact bone of the flexor cortex of the distal sesamoid bone had low intensity signal on all sequences. In 11 digits an increased signal was seen within the thickness of the sagittal eminence of the flexor cortex in SE T1-weighted images and in TSE PD-weighted images without FS. Trabecular bone had a granular appearance and high signal in SE T1-weighted sequences and TSE images without FS. The deep digital flexor tendon had low signal on FS T2-weighted images, while on short echo time sequences (T1- and PD-weighted sequences), the tendon signal varied depending on the relative orientation between its fibers and the static magnetic field. Seven tendons had stippled appearance due to small intratendonous foci of slightly increased signal on transverse T1-weighted images. MR imaging provides a thorough evaluation of the anatomical structure of the podotrochlear apparatus: A good knowledge of the MR imaging appearance and anatomy and an awareness of potential pitfalls will improve diagnostic specificity for the detection of pathologic changes. [less ▲]

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