Ebara's concern over environmental measures, in particular against global warming, has led to our development of a novel power saving dry vacuum pump series for the semiconductor manufacturing industry. As this series enables an 83% saving in energy consumption, it is expected to replace conventional models used in this industry. Enthusiastic promotion for this product is currently underway.

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  We observed the Verwey transition, metal-insulator transition, in a spin-polarization of field-emitted electrons from a topmost surface of a 〈110〉-oriented magnetite whisker by means of field-emitted electron polarimetry. Raising temperature of the whisker to about 120 K, the polarization of field-emitted electrons increased from 4 to 11% with a rotation of its direction. The rotation angle corresponds to a change of magnetic easy axis from 〈001〉 to 〈111〉 direction caused by the Verwey transition. At magnetite temperature of 40 K, the spin polarization was sensitive to increase of the applied field. Eventually, the direction of spin polarization reversed, which can not be explained taking in to account conventional free electron model. These results reveal that the Verwey transition occurs even at a surface as well as in a bulk and that the energy width and level of t_2g band become narrower and lower than that of bulk.

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  In order to measure the pressure at extremely high vacuum practically, a new design of ionization gauge is studied with the computer simulation. The new gauge has simple structure, and is operated so that electrons reciprocate many times. To avoid the undesirable effect due to the space-charge formed by the electrons, this oscillation is periodically stopped by modulating the potential of the filament. Then, the sensitivity of this gauge shall be about several-tens times higher than that of the usual B-A gauge, and the pressure at extremely high vacuum can be measured rather easily.

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  The resistance property of a single chamber fuel cell (SCFC) using a boehmite inorganic electrolyte as the proton conductor was studied by using alternating-current impedance method at room temperature operation (RT) in the dry gas mixtures of hydrogen and oxygen. The open circuit voltage (OCV) and maximum current density of SCFC using the Pt/CB electrode as anode and the Au or Pt electrodes as cathode were attained 776-690 mV and 0.13-0.17 mA/cm². The cell resistance of SCFC using the Pt electrode became smaller value as compared with that using the Au electrode. The OCV of SCFC corresponded to a development index of polymer electrolyte fuel cell (PEFC), although the current density became lower than that of PEFC.

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