The Ce-Ni-Si System Revisited: More Homologue Compounds?

The nickel-rich region of the system Ce-Ni-Si has been reinvestigated utilizing X-ray single-crystal, powder, and electron diffraction as well as electron microprobe and thermal analyses. Two novel hexagonal compounds, τ-CeNiSi and τ'-CeNiSi were identified. The crystal structure of τ-CeNiSi was derived from single-crystal X-ray diffraction and found to be isotypic with the SmNiP-type structure (S.

Analysis of Magneto-Optical Hysteresis Loops of Amorphous and Surface-Crystalline Fe-Based Ribbons.

Three Fe-based ribbon-type samples prepared by a conventional planar flow casting process are studied from the viewpoint of the amorphous FeSiB and partially surface crystallized FeSiB, and FeNbB, microstructures. Surface magnetic properties are investigated by magneto-optical Kerr microscopy, allowing the measurement of a local hysteresis loop from a selected area on the ribbon surface, and simultaneously, a domain structure corresponding to a definite point at the loop. For an amorphous sample, the changes in the slopes of hysteresis loops are related either to the size of the selected surface area, from which the loop is measured, or to the type, width, and movement of magnetic domains through this area.

Morphology Control in AgCu Nanoalloy Synthesis by Molecular Cu(I) Precursors.

As nanoparticle preparation methods employing bottom-up procedures rely on the use of molecular precursors, the chemical composition and bonding of these precursors have a decisive effect on nanoparticle formation and their resulting morphology and properties. We synthesized the Cu(I) complexes [Cu(PPh)(bea)] (, bea = benzoate) and [Cu(PPh)(Hphta)] (, phta = phthalate) by reducing the corresponding Cu(II) mono- and dicarboxylates with triphenylphosphine. We characterized and by single-crystal X-ray diffraction analysis, elemental analyses, infrared and nuclear magnetic resonance spectroscopy, and mass spectrometry and obtained complete information about their structures in the solid state and in solution.

Study of thermal stability of p-type skutterudites DDFeCoSb by Knudsen effusion mass spectrometry.

The temperature and phase stability of p-type skutterudites, DDFeCoSb, manufactured various preparation techniques, all exhibiting a high -level, have been studied by means of thermal analysis and Knudsen effusion mass spectrometry. The results from phase transformation measurements and characteristics of the evaporation of antimony, as the volatile element, supported by microstructure observations and by diffusion profiles are summarized and discussed in view of a full understanding of the degradation processes and knowledge of the long term operation stability of the bulk and nano-structured thermoelectrics studied. It was found out that the antimony evaporation is a complex diffusion kinetic process resulting in a stable Sb level dependent on the preparation route.

Influence of Preparation Technology on Microstructural and Magnetic Properties of Fe₂MnSi and Fe₂MnAl Heusler Alloys.

Microstructural and magnetic properties of the X₂YZ, namely Fe₂MnSi and Fe₂MnAl, Heusler alloys have been studied from the viewpoint of technology for their production and for the Z element effect. First, arc melting was applied to produce button-type ingots from which samples in a form of 500 µm thick discs were cut. Second, planar flow casting technology yielded samples in a ribbon-form 2 mm wide and 20 μm thick.

Heat-induced spinodal decomposition of Ag-Cu nanoparticles.

Solvothermal synthesis was used for Ag-Cu nanoparticle (NP) preparation from metallo-organic precursors. The detailed NP characterization was performed to obtain information about nanoparticle microstructure and both phase and chemical compositions. The resulting nanoparticles exhibited chemical composition inside a FCC_Ag + FCC_Cu two-phase region.

Changes in microstructure and physical properties of skutterudites after severe plastic deformation.

The best p-type skutterudites with ZT > 1.1 so far are didymium (DD) filled, Fe/Co substituted, Sb-based skutterudites. DD0.

Near-field scanning optical microscope probe analysis.

In this article results of a comparison of two NSOM probe characterization methods are presented. Scanning electron microscopy analysis combined with electromagnetic field modeling using the finite difference in time domain method are compared with measured far-field radiation diagrams of NSOM probes. It is shown that measurement of far-field radiation diagrams can be an efficient tool for daily checking of the NSOM probes quality.