A large quantity of engineering plastics are used in electric industrial products. It is necessary to estimate the life of the product made of engineering plastics because of its shorter life and lower strength than some of ceramics or metals. Polybutylene terephthalate is one of the hydrolyzed engineering plastics. Their test pieces were submitted to accelerated stress test of elevated temperature and humidity. Their strength was evaluated by three-point bending test. It was found that the strength degradation was related to water vapor pressure, temperature and retention time. It was possible to estimate the time required for strength degradation in service environment.

This study systematically analyzed life cycle CO₂ (LCCO₂) emissions of a comprehensive set of mass-produced 2,000 cc class sedan-type vehicles, using a hybrid life cycle inventory approach. Gasoline and diesel internal combustion engine vehicles (ICEVs), hybrid electric vehicle (HEV) as well as battery electric vehicle (BEV) and fuel cell vehicle (FCV) were investigated, considering (i) the current BEV market trends, (ii) Japan’s energy mix (the average for 2012–2014), and (iii) the use of the HVAC system. The results show that the annual average increment of CO₂ emissions in use phase by HVAC system in Japan (assumed annual mean temperature of 15°C) was presumed to be evenly 9% regardless of vehicle types, although further detail analysis is required. The CO₂ emissions in use phase of BEV were higher than those of HEV and FCV (applied hydrogen produced by steam reforming of LPG (on-site)) due to thermal power dominant electricity generation mix in Japan in recent years. As a consequence of high CO₂ emissions from power supply and battery production, the LCCO₂ emissions of BEV equipped with 75 kWh battery were higher than those of HEV, FCV (on-site), and conventional ICEV (diesel). By reducing the battery capacity to 40 kWh or less, the LCCO₂ emissions of BEV become lower than those of ICEVs and FCV (on-site), making BEV a competitive alternative. However, it is difficult that BEV mitigates both LCCO₂ emissions and driver’s range anxiety. In conclusion, HEV shows the competitive performance in terms of LCCO₂ emissions with long driving range in Japan.

A flat thrust bearing, that has a structure which generates a pressure flow by using the discontinuity of shear flow rate between a water-repellent surface and a hydrophilic surface, was developed. In this study, ultrasonic pulse echo technique was employed for the investigation of the film thickness influenced by the static contact angle θ (≅10°, 60°, 110°) and the water-repellent area ratio β(=0.25, 0.5, 0.75). Since the occurrence of the slip of water at a water-repellent surface having 110° of static contact angle is easy, observed lubrication film thickness is thicker than that of θ≅60°, and the film thickness at θ≅10° becomes thinnest. The film thickness is different by the area ratio β of water-repellent region against a bearing surface area, and it thickens in order of β=0.25, 0.75, 0.5. Thickest film is formed around of the β where the area of water-repellent region is equal to hydrophilic area. Calculation results of the infinite long bearing approximation, which considered the slip on a wall, agree with the characteristics of measured film thickness mentioned above. Therefore this thrust bearing operates under similar mechanism with conventional bearing having lubrication surfaces which shapes a wedge film. The order of measured film thickness agrees with order of satisfactory bearing of friction characteristics in each bearing tested. Consequently it can be conclude that the main factor of which coefficient of friction under a same load and speed is different by static contact angle θ and water-repellent area ratio β is a variance of film thickness in each bearing.