We have investigated the formation and the microwave dielectric properties of the Ba4(Nd28/3-y  R y)Ti18O54 (R = Eu, Dy, Ho, Er and Yb) solid solutions in which R ions are substituted for Nd ions in Ba6-3x Nd8+2x Ti18O54 solid solutions with x=2/3. Based on the change of the volume of the unit cell, it was inferred that Eu, Dy, Ho and Er ions substituted into rhombic A1-sites, but Yb ions did smaller sites such as B-sites and C-sites after substituting A1-sites. The quality factor (Q·f) improved as the ionic radius of substituted R ions increased. In the Eu series, the best Q·f value of 10405 GHz was obtained. The temperature coefficients of the reasonant frequency (τ f ) in the Dy, Ho and Er series were improved by more than 50%, but the dielectric constant (ε r ) showed only a nominal change of about 3–4 in the vicinity of 80.

A new approach has been developed to numerically calculate solid angles of the ligands in organometallic complexes. The novelty of the method is in using atomic radii corresponding to the distance where the Morse potential becomes zero, rather than in using the "typical" atomic van der Waals radii corresponding to the minimum of the Morse function. The calculated values include the ligand solid angles, the corresponding cone angles (rather than Tolman cone angles), the ligand special overlaps, ligand overshadowing, and the molecular solid angle. In addition, the calculated solid and cone angles are normalized to a Metal-Ligand distance of 2.28 Å to allow facile comparison of ligand steric demands in complexes of different metals with different compositions of coordination spheres. The new approach has been implemented in the program Solid-G and solid angles parameters with standard deviations have been computed for most common ligands such as cyclopentadienyl and tri-substituted phosphines. The new approach allos to evaluate the conformational flexibility of the ligands. The epitaxial cubic symmetric CrPt 3 films exhibit a perpendicular magnetic anisotropy (PMA) with large Kerr rotation angles. In order to understand the PMA effect of such a cubic CrPt 3 thin film, the directional chemical order parameters S and polarization dependent x-ray absorption fine spectroscopy (XAFS) were measured in both in-plan and plane-normal directions. The best PMA effect can be found when the plane normal order parameter is largest while the in-plane one is still low. At the same time, Cr-Cr bond-distance have slight distortion by XAFS analysis. This anisotropic directional long range chemical order might be due to the anisotropic interdiffusion and the compound formation between the Cr and Pt layer. For a short-range order analysis, the PMA effect might be attributed to the difference of the Cr-Cr bond-distance between plane-normal and in-plane directions. Tungstenbronze-type-like (Ba 1-Sr) 6-3x R 8+2x Ti 18 O 54 (R = rare earth) solid solution is one of the microwave dielectric materials. The crystal data is as follows: orthorhombic, Pbnm (No. 62), a 12, b 22, c 7 Å and Z = 2. The crystal structure of the solid solution is composed of two kinds of large cation sites: four pentagonal sites with Ba ions and ten rhombic sites with Ba, Sr and R ions in the framework formed by TiO 6 octahedron. These single crystals for R = Sm and Nd system were synthesized by conventional cooling method and FZ method, respectively. The X-ray diffraction data were obtained by a diffractomater with imaging plate (Rigaku; R-AXIS RAPID). Structural parameters were refined by full-matrix least-squares (RADY) [1]. All Sr ions occupied rhombic sites. Especially, one rhombic sites had more amount of Sr ions as compared with another rhombic sites in both of the R = Sm and Nd system. These solid solutions have relationship between distribution of cations and microwave dielectric properties [2]. Therefore, improvement of these properties with increasing compo...

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Heat-resistant alloys are superior to stainless steel or heat-resistant steel in high-temperature strength and heatresistance, and therefore are used in various industrial applications.Typical heat-resistant alloys include nickel-based alloys such as Inconel and Waspaloy, which are used in aircraft engine turbine parts, shafts, cases and generation turbine parts.While they are known for excellent high-temperature strength and heat resistance, they are also known as significantly difficult-to-process metals because hardening is more likely to occur and dispersing of the heat generated by cutting is slower as its thermal conductivity is smaller than that of carbon steel and the like that it can impact manufacturing cost.Meanwhile, in order to improve fuel consumption rate (SPC: Specific Fuel Consumption), aircraft engine manufactures have been developing various products such as high-temperatures, and high-efficient combustors with low-environmental impact. Apparently, it is expected that the next-generation heat-resistant alloys will become even more difficult to process.In this paper we will introduce some cutting tool materials for handling those alloys as well as new cutting materials we have developed to support machining them.