For the production of refrigerators, CO₂ emissions was estimated as affected by variations in estimation of CO₂ emissions from electricity production, and differences in the process data and system boundaries used in the bottom-up approach. The results indicate that the amount of CO₂ emitted in raw materials production was influenced by variations in CO₂ per kWh electricity consumed, but the ratio of CO₂ emis-sions from direct processrelated sources was not influenced. The amount of CO₂ emis-sions in material production and the ratio of CO₂ emissions in material production were influenced by the process data and system boundaries used in the calculations. In particular, as the process of aluminum ingots lead to large CO₂ emissions, it is necessary to carefully consider the system boundary definition use when comparing estimates obtained from different data sources.
The estimated CO₂ emissions obtained via the bottom-up approach was then compared to that obtained using the Input-Output table analysis. The total CO₂ emissions and the relative contribution of different sources in material production were influenced. It is also important to note that the calculated value using the Input-Output table is smaller than that from the bottom-up approach. It is reason that the data in the Input-Output table do not go into sufficient detail.

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Life cycle inventories for two types of washing machines (water-saving type and conventional type) were developed to investigate the total CO₂ emissions during the life cycle. Additional life cycle inventories for detergent and city water consumed during the use of the washing machines were calculated. CO₂ emissions attributable to treatment of Biochemical Oxygen Demand (BOD) which is contained in washing machine waste water was also added to the life cycle inventories. It was concluded that the watersaving type washing machine can reduce the total amount of CO₂ emissions during the life cycle by 5.3% compared to conventional washing machines.

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Ignition and combustion characteristics of a coal-oil mixture drop have been measured under normal and micro gravity conditions in order to get fun-damental understandings on combustion processes of a coal slurry spray. The experi-ment were conducted in a drop tower, which has a fall of 710 m and a duration of 10 seconds of the microgravity condition. In this study, Taiheiyo Coal and n-Dodecane were used for coal-oil mixture which has a 50 % mixing ratio. The Taiheiyo Coal had a fixed coal mass percentage of 43.03 %, a volatility mass percentage of 40.97 % and an ash mass percentage of 16.00 %.
A mass percentage of the Taiheiyo Coal with a diameter smaller than 75 mm was 85.74%. Comparison of the experimental results between under the microgravity condi-tion andunder the normal gravity condition clarifies differences in combustion charac-teristics between the two. The minimum ignition temperature under microgravity is more than 380 K lower than that under normal gravity, and the ignition delay of the COM drop under microgravity is shorter than that under normal gravity.

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