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Magnetic structure of Nd<sub>7</sub>Co<sub>6</sub>Al<sub>7</sub>
No full textTime-of-flight neutron powder diffraction has been used to determine the magnetic structure of the intermetallic compound Nd7Co6Al7. The thermodynamic, magnetic and electrical properties of this compound indicate that it undergoes a paramagnetic-ferromagnetic transition at 15.5 K, and possesses a magnetic refrigerant capacity of approximately 40 J/kg. The average value of the high field saturation magnetic moment per Nd atom at low temperatures is almost 50% below that of the free ion value. Neutron powder diffraction measurements have been performed at 300 K, in older to confirm the details of the crystal structure, and below the magnetic ordering temperature, at 6 it, in order to establish the nature of the magnetic structure. The high temperature data clearly confirm that Nd,Co,Al, crystallizes in the Pr7Co6Al7 structure (space group P4/mbm). The low temperature data show the presence of reflections at (100), (110), (200) and (210). reflections which are non-existent above the ordering temperature. The presence of the (100) reflection indicates the presence of antiferromagnetic configurations in this system. Models of the magnetic structure for Nd7Co6Al7 will be presented and discussed
Le ceramiche grezze nel Modenese: Studi recenti e prospettive di Ricerca
No full textdalla composizione al riconoscimento delle tecniche impiegate nella preparazione e decorazione delle ceramich
Structure and magnetic properties of Nd2Co17-xGax compounds studied by magnetic measurements and neutron diffraction
No full textMagnetic and crystal structure of Th-Fe-Sn intermetallics: ThFe0.22Sn2 and Th4Fe13Sn5
No full textThe crystal and magnetic structures of two new ternary phases in the Th-Fe-Sn system: ThFe0.22Sn2 and Th4Fe13Sn5 have been investigated by high-resolution neutron powder diffraction, The ThFe0.22Sn2 phase crystallizes in an orthorhombic crystal structure, space group Cmcm, whilst Th4Fe13Sn5 crystallizes in the tetragonal space group P4/mbm. In agreement with bulk magnetization measurements, the compound ThFe0.22Sn2 does not order magnetically in the temperature range investigated, while Th4Fe13Sn5 orders below 375 K, with the easy magnetization direction of the Fe moments aligned along the tetragonal c-axis
Note on the crystal structure and magnetic properties of Ce2Ni17Si9 and Ce2Co17Si9 compounds
No full textMisure archeometriche su ceramiche grezze romande di area padana
No full textstudio dei materiali per la preparazione di impasti ceramici antichi
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Neutron diffraction and magnetization measurements of Tb<sub>2</sub>Co17<sub><i>-x</i></sub>Ga<sub><i>x</i></sub> intermetallics
No full textThe crystallographic and magnetic structures of Tb2Co17−xGax (x = 1, 3, 5 and 7) intermetallics have been investigated by time-of-flight neutron powder diffraction at 293 and 4.2 K. All four compounds crystallize in the rhombohedral Th2Zn17 structure (R 3¯ m) with Co atoms fully occupying the 9d site whilst Co and Ga atoms are found to distribute themselves in a non-random manner on the remaining 6c, 18f and 18h sites. These observed site occupations can be correlated with the sign reversal of the Co sublattice magneto-crystalline anisotropy for Ga concentrations x > 3. The magnetic structures of the Tb and Co sublattices have also been refined from the neutron-diffraction data and indicate a complex ferrimagnetic behaviour with Ga composition. The Co moment decreases in size with Ga concentration, as does the Curie temperature
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