Multielement oscillators with a quasi-optical resonator are reported. The resonator consists of a Fabry-Perot cavity with a grooved mirror (grating) and a concave mirror. It is possible to mount solid-state devices (Gunn diode, GaAs MESFET, etc.) in the grooved mirror. The oscillator has the capability for power-combining of solid-state sources in the millimeter- and submillimeter-wave regions.< >
Bioactivity of zirconia-toughened glass-ceramic composites was evaluated in terms of their surface reaction in simulated body fluid. The bioactivity was degraded by introducing large amounts of zirconia TEM observation revealed that Ca in the glass-ceramic particles reacted with the zirconia during sintering, and that the decrease in Ca in the particles degraded the bioactivity of the composites. In this study, the optimum composition and preparation process are determined for high-strength and bioactive ceramics.
CoNiCr/Cr films were sputtered onto polished glass at temperatures T s ranging from 25 to 400°C, and their magnetic properties were investigated in connection with their micro-structure. H c was found to increase with increasing T s while sputtering GoNiCr/Cr films, which consisted mainly of an h.e.p. phase. Analytical transmission electron microscopy revealed that the underlayer Cr diffused into grain boundaries of the CoNiCr layer, and at higher T s , into individual CoNiCr grains. Torque loss analyses were performed to determine the magnetic isolation among CoNiCr grains. The uniaxial magnetic anisotropy field for individual grains determined experimentally, H kgrain (exp), was found to increase with increasing Ts. Metalographical change promoted magnetic isolation among h.e.p. CoNiCr grains, and as a result, the microscopic demagnetizing field in each CoNiCr grain increased. This conclusion is well supported by the experimental results of the torque loss analysis in this work.
Magnetic properties were investigated for CoNiCr/Cr films sputtered on polished glass at Ts ranged from 25 to 400°C in connection with microstructure. Hc was found to increase when increasing Ts for CoNiCr/Cr films, which consisted mainly of h. c. p. phase. Microscopical elemental analysis by electron beam revealed that Cr as underlayer diffused gradually into grain boundary of CoNiCr films and into each grain of CoNiCr with higher Ts. Torque loss analysis was made to determine the magnetic isolation among CoNiCr grains. Uniaxial magnetic anisotropy field of each grain determined experimentally Hkgrain (exp.) was found to increase when increasing Ts. Metalgraphical change promoted magnetic isolation among h. c. p. CoNiCr grains and as a result, microscopical demagnetizing field in each CoNiCr grain increases. This conclusion is well supported by the present experimental results of the torque loss analysis.
