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Theoretical saturation magnetization and magnetocrystalline anisotropy energy (MAE) of τ-phase (face-centered tetragonal) Mn50Al50 alloy were obtained by first principles calculations, and the alloy was fabricated to compare the experimental values with the theoretical predictions. The calculated magnetic moment and MAE for τ-phase Mn50Al50 were 2.37) μg/ f.u. and 0.259 meV/f.u. (1.525×106 J/m3), respectively, which result in the maximum energy product (BH)max of 12.64 MG Oe and the magnetocrystalline anisotropy field of 38 kOe. The saturation magnetization for τ-phase Mn54Al46 alloy was measured to be 98.3 emu/g, which gives 4.7 MG Oe of (BH)max. The magnetization is about 70% of the theoretical value of 144 emu/g. [ABSTRACT FROM AUTHOR]

The effect of Mn and/or Co doping in Ni–Mn–Co ferrite on the static, dynamic magnetic properties, and thermal magnetic stability were investigated for high frequency microwave applications up to the gigahertz range. Saturation magnetization and coercivity increased with increased substitution of Mn and Co, respectively. Both Mn and Co substituted Ni–Mn–Co ferrite exhibited higher thermal stability factor rather than Ni–Mn and Ni–Co ferrites. The highest thermal stability factor was achieved to be -12.0×10-4 °C/ppm for Ni0.93Mn0.05Co0.02Fe2O4. The second highest, -11.88×10-4 °C/ppm, was measured for Ni0.7Mn0.05Co0.02Fe2.23O4. Permeability (μ), permittivity ([variant_greek_epsilon]), and cutoff frequency of Ni0.93Mn0.05Co0.02Fe2O4 and Ni0.7Mn0.05Co0.02Fe2.23O4 showed 7.41, 4.56, 1084 MHz, and 3.87, 4.55, 1436 MHz, respectively. Furthermore, the μ/[variant_greek_epsilon] ratio of Ni0.93Mn0.05Co0.02Fe2O4 was found to be 1.63 (μ/[variant_greek_epsilon]=7.41/4.56). [ABSTRACT FROM AUTHOR]

Feasibility of the electrophoresis deposition (EPD) technique for homogeneous and adhesive deposition of DyF3 particles on the Nd-Fe-B-type particles was studied, and coercivity enhancement in the diffusion-treated Nd-Fe-B-type particles deposited with DyF3 by EPD was investigated. HDDR-treated Nd12.5Fe80.6B6.4Ga0.3Nb0.2 particles were deposited with DyF3 particles by EPD. More homogeneous and adhesive deposition of DyF3 particles on the surface of Nd-Fe-B particles was made by the EPD with respect to conventional dip-coating, and this led to more active and homogeneous diffusion of Dy. More profound coercivity enhancement was achieved in the diffusion-treated Nd-Fe-B-type particles deposited with DyF3 by EPD compared to dip-coated particles. [ABSTRACT FROM AUTHOR]

This study was performed to examine whether capsaicin, the main pungent ingredient of red peppers, exerts protective effects against testicular injuries induced by transient scrotal hyperthermia. Capsaicin (0.33 mg kg−1) was administered subcutaneously to mice one hour before heat stress ( HS) in a 43°C water bath for 20 min. After 7 days, mice exposed to HS showed low testicular weight, severe vacuolisation of seminiferous tubules followed by loss of spermatogenic cells, and appearance of multinucleated giant cells and remarkable TUNEL-positive apoptotic cells, as well as weak immunoreactivity of phospholipid hydroperoxide glutathione peroxidase ( PHGPx) in spermatogenic cells. Levels of lipid peroxidation and heat shock 70- kDa protein 1 (Hsp72) and BCL2-associated X protein (Bax) mRNA were greatly increased, but PHGPx, manganese superoxide dismutase (Mn SOD), and B-cell lymphoma-extra large (Bcl- xL) mRNAs were significantly diminished in the testes by HS. However, capsaicin pre-treatment significantly suppressed the spermatogenic cell death, oxidative stress (levels of MDA, PHGPx immunoreactivity, and Hsp72, PHGPx, and Mn SOD mRNA) and apoptosis (levels of TUNEL-positive cells, and Bcl- xL and Bax mRNA) in testes by HS. These suggest that capsaicin has a protective effect against spermatogenic cell death induced by scrotal hyperthermia through its antioxidative and anti-apoptotic activities. [ABSTRACT FROM AUTHOR]

Nd-Fe-B-type die-upset magnet with high electrical resistivitywas prepared by doping of eutectic DyF3-LiF salt mixture. Mixture of melt-spun Nd-Fe-B flakes (MQUF: Nd13.6Fe73.6Co6.6Ga0.6B5.6) and eutectic binary (DyF3-LiF) salt (25 mol% DyF3 - 75 mol% LiF) was hot-pressed and then die-upset. By adding the eutectic salt mixture (> 4 wt%), electrical resistivity of the die-upset magnet was enhanced to over 400 μΩ.cm compared to 190 μΩ.cm of the un-doped magnet. Remarkable enhancement of the electrical resistivity was attributed to homogeneous and continuous coverage of the interface between flakes by the easily melted eutectic salt dielectric mixture. It was revealed that active substitution of the Nd atoms in neighboring flakes by the Dy atoms from the added (DyF3-LiF) salt mixture had occurred during such a quick thermal processing of hot-pressing and die-upsetting. This Dy substitution led to coercivity enhancement in the die-upset magnet doped with the eutectic (DyF3-LiF) salt mixture. Coercivity and remanence of the dieupset magnet doped with (DyF3-LiF) salt mixture was as good as those of the DyF3-doped magnet. [ABSTRACT FROM AUTHOR]

Harnessing cathodic hydrogen atom generation, metals such as Pt, Pd, Cu, Au and Ni are directly electrodeposited on functionalized dielectric layers of 6 nm thick silicon oxide formed by thermal oxidation of c-Si substrate. Modifying the oxide layer with functional molecules and Au nanoparticles by simple wet chemistry, we can enhance electrodeposition efficiently and thereby electroplate nanoparticles of Pd and Pt to obtain such thin metal films. In particular, Au nanoparticles on amine-modified silicon oxides remarkably enhance electrodeposition of metal nanoparticles to create sturdy metal films on the dielectric layer, n+-Si/SiO2-NH2. Such enhancement is ascribed to good affinity of Au nanoparticles with electrodeposited metal as well as enhanced current density across the silicon oxide. For an example of potential applications, we show one-step electrodeposition Pd film on dielectric layers to fabricate conductometric hydrogen gas sensor without transferring Pd film. [ABSTRACT FROM AUTHOR]

Focuses on a study which developed a material for thermally stable self-aligned silicide technologies using sequentially deposited titanium/tantalum on polycrystalline silicon. Benefits of smaller integrated-circuit dimensions; Significance of nitrogen on the stability of semiconductor structures; Factors influencing the critical temperature of recrystallization.

Investigates the formation on titanium silicides on silicon implanted with different boron-fluorine dosages. Use of secondary ion mass spectrometry and transmission electron microscopy measurements; Effect of residual oxides on the silicide formation; Impurity distribution profiles of silicon samples implanted with fluence of boron-fluorine.