13 research outputs found
An Organo-Metallic Polymer Used in Powder Metallurgy : The Effect of Polycarbosilane in Iron-Chromium Alloy(Metallurgy)
A new material was developed by introducing an organo-metallic polymer into powder metallurgy. In the uniform mixture of Fe-13Cr^* alloy powder and polycarbosilane (PC) using n-hexane, the Fe-13Cr particles were coated with PC. The product of Fe-13Cr+10wi%PC, obtained by hot-pressing the mixture, was subjected to an oxidation test, high-temperature hardness measurement and a wear resistance test, and found to be superior in all respects to that without the PC addition. The structure was observed by transmission electron microscope and it was found that grains of CrSi_2 and Cr_7C_3 about 0.1μm in size, dispersed uniformly in the Fe-13Cr+10%PC, contributed to improvement of the mechanical properties. Observation by scanning electron microscope showed some difference in the formation of the oxidation film between Fe-13Cr and Fe-13Cr+10%PC. This new alloy, while adding an organo-metallic polymer to powder metallurgy, has several outstanding features with the possibility of many applications in the future
Observation of water-window soft x-ray emission from laser-produced Au plasma under optically thin condition
We present a systematic approach how to charactorize the dynamics of a laser-produced Au plasma, generated with a commercial Joule-class laser system. By means of our diagnostic methods, we identify the dominant ionic species within the water-window spectral region, as well as the radiated energy, the x-ray emission duration and the total dimensions of the x-ray source. We present additional analysis through radiation hydrodynamic simulations to provide details about the electron temperature and density profiles and further show that the plasma exhibits nearly 20% self-absorption, while the electron temperature is limited to 400 eV. A comparison with the experimental data further allows us to verify the applied numerical code
Observation of keV X-ray emitted from laser produced Au plasmas by using a crystal spectrometer
X-ray emitted by a laser generated plasma has various applications. Serious issue to be solved is thatthe energy conversion e?ciency from the laser to X-ray is quite low. Recently, it was found that the X-ray emitted by the laser produced Auplasma increases under nitrogen atmospheres. In particular, the intensity of the water window soft X-ray (2.4-4.4 nm) increases approximately ten times. In order to elucidate this enhancement mechanism of X-ray, we have measured soft X-ray spectra from Au plasma in the wavelength of 1-7 nm so far. Recently, we fabricated a TAP crystal spectrometer to observe the photons over 1 keV region (1.0-1.9 eV), which provides useful information of plasma temperature. As a detector, an imaging plate(IP) was used. Titanium ?lters was also used to block out-of-band emission. As a result, continuum spectra attributed unresolved transition arrays (UTAs) was observed from the Au laser plasma. This spectral profile was compared with the Star2D hydrodynamic code.DPP19 Meeting of The American Physical Societ
Observation of water-window soft x-ray emission from laser-produced Au plasma under optically thin condition
Observation of keV X-ray emitted from laser produced Au plasmas by using a crystal spectrometer
Neutron Irradiation Effects on Thermally Activated Process of Tensile Properties of Titanium
Enhancement of water-window soft x-ray emission from laser-produced Au plasma under low-pressure nitrogen atmosphere
Photoemission and inverse photoemission study of the electronic structure of C60 fullerenes encapsulated in single-walled carbon nanotubes
We have measured the valence-band photoemission and inverse photoemission spectra of single-walled carbon nanotubes (SWNTs) with mean radii of 0.7 and 0.64 nm encapsulating C60 fullerenes (peas), so-called "peapods." The photoemission spectrum of the C60 peas in the SWNTs is obtained by subtracting the spectrum of empty SWNTs from the spectrum of the peapod. The structures in the C60 pea spectra correspond well to those in the spectrum of a C60 face-centered-cubic solid. No structure is observed at binding energies ranging from the Fermi level (EF) to the onset of the highest occupied molecular orbital (HOMO) peak; the t1u level of the C60 peas inside the SWNT stays above EF