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We have fabricated ferromagnetic Fe-oxide nanoparticles as a candidate of hysteresis-loss heating materials used for hyperthermia and thermoablation and examined heating abilities. The coercivities were controlled in a range between 50 Oe and 240 Oe. The temperature-rising characteristics were examined for randomly oriented solid nanoparticles by applying a 17-kHz ac magnetic field with an amplitude up to 550 Oe. A temperature rising rate ΔT/Δt was proportional to the square of the peak magnetic field H0 in the lower H0 region; however, the relation dose not hold at higher H0. The maximum loss power was obtained to be 4 W/g, which is smaller than the value expected from the minor loop experiment (13.7 W/g). The reason for small heating capability is discussed. [ABSTRACT FROM AUTHOR]

We have recently reported the successful development of a fully coherent X-ray laser (XRL) at 13.9 nm by an oscillator-amplifier configuration with two targets. In the experiment, a seed XRL beam from the first target is injected into a plasma amplifier at the second target. The observed XRL beam has full spatial coherence and 0.2 mrad of nearly diffraction-limited divergence. In order to improve the output fluence, the amplification properties of the XRL beam have been investigated using various plasma lengths of the second amplifier target. The output energy has been improved by a factor of ten, increasing the length of the gain region to 10 mm, resulting in about 0.2 μJ of output energy. [ABSTRACT FROM PUBLISHER]

We have developed nanosized composite advanced particles (NanoCAP) with spherical shape and high coercivity, and fabricated dual coated tape to evaluate playback performance. The spherical shape contributes to smooth surfaces and reduced boundary variation between the magnetic layer and underlayer. The fine particle size, 17 nm, yields low media noise and high signal-to-noise ratio. The high coercivity, compared to metal particulate media, contributes to high amplitude resolution (D50 = 170 kfci). We confirmed that write demagnetization is well restrained and that NanoCAP tape should show very good playback performance with a superior writer. [ABSTRACT FROM AUTHOR]

For high-density recording tape, NanoCAP was developed using co-precipitation and nitridation treatment in an NH3 gas atmosphere. Each particle has a spherical shape with a diameter of about 17 urn and a core-shell structure. The core and shell mainly consist of the Fe16 N2 and oxides containing Al and Y, respectively. The saturation magnetization and the coercive force are 85.5 A m²/kg (85.5 emu/g) and 227 kA/m (2850 Oe), respectively. The coercive force is a higher value that of the needle-shaped particles currently used and is stable from room temperature to 323 K. The higher coercive force originates from an uniaxial magnetic anisotropy of the Fe16 N2. [ABSTRACT FROM AUTHOR]

Provides information on a study that described the magnetic and structural properties of nano-sized FeCo particles containing samarium and boron prepared by a co-precipitation method. Experimental procedure; Results and discussion on the study; Conclusion.