Masayoshi Taki

Comparison between the energies of ejected ions in the cases of KrF laser ablation and Ar ion sputtering

Abstract The kinetic energy distributions of positive ions ejected from Si, Co, Ni and Pb-Zr-Ti-O targets subjected to KrF excimer laser or Ar ion irradiation were measured. It was found that the average energies of the ejected ions originating from laser ablation were in excess of 100 eV, while those from Ar ion sputtering were a few tens of eV. The energy distributions of the ejected ions by laser ablation were peculiar ones, characterized by having a lot of peaks, which are throught to show the plasma states on the target surface, for example generation of high electrical field. On the other hand, the energy distributions in the case of Ar ion sputtering showed the ones based on the collision cascade process.

A new catalyst system for endothermic gas production

Research has been conducted on a gas carburizing atmosphere system for better quality control and energy savings. In this paper a new and excellent catalyst for producing endothermic gas at low temperatures is introduced.The conventional endothermic gas catalysts, such as a nickel catalyst, are used in a space velocity (SV) of 400–600/hr at a high temperature (about 1100° C). The new catalyst can be used in a high space velocity of 6000–12000/hr at a lower temperature (about 950° C). The composition of the new catalyst is cobalt supported on an alumina magnesia spinel.The catalyst was examined under various severe conditions. As a result, the catalyst’s deterioration was almost never observed under normal operating conditions (SV: 12000/hr, 930° C). The durability tests using various practical reforming furnaces were successfully conducted from 6–16 months. The higher efficiency and lower operating temperature of this new process results in an electrical energy savings of about 40%.