The dechlorination experiments of PCBs were carried out with the different conditions of the SD particle size, the Na/Cl equivalent ratio, the PCB dropping concentration, the SD management, the stirring speed and the kind of PCBs. The fundamental operation conditions for the proper dechlorination process were clarified. The safety factors of the dechlorination process by sodium dispersion were extracted.
The dechlorination reaction can be carried out stably under the conditions with reaction temperature of 160 degree centigrade, PCB dropping time of 2.5 hours, SD concentration of 15wt%, Na/Cl equivalent ratio of 1.5, the SD particle diameter of 10μm or less, and the PCB concentration of 15wt%. The activity of SD particle surface fell during the standby time and the management state of SD particles before reaction start may affect the reaction greatly. It is possible to control the size of PCB residues with the change of the stirring speed. The dechlorination process of KC1000 is shown as well as KC400 under the same reaction conditions.

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Psychological responses and permissible limits of 20 subjects under intermittent rattling noise of a fitting were measured. A subject sits in front of the fitting with glass plates and answers questionnaires for psychological state in/after exposure of intermittent rattling noise from the fitting exposed to low frequency noise. The fitting rattles 10 s cyclically with silent time. The values of ‘loud’, ‘can't bear as living room’ and ‘can't bear as bed room’ increase according to duty factors of rattle time. Permissible limits were measured by L_{Aeq 5 s} of rattling noise adjusted by subjects themselves. The permissible limit decreases according to duty factor. Calculated L_Aeq from L_{Aeq 5 s} was almost constant.

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A route planning program of the hot-water piping of a fuel cell energy network for a central system and distributed system has been developed. A city area model of 74 buildings in Sapporo was applied to the route planning program, and quantity of heat loss of the hot-water piping and piping route was investigated. Consequently, compared with the central system, the piping heat loss annually of the distributed system is 75%. When there is less than ±30% load fluctuation, compared with where there is no load fluctuation, heat loss is cut by 6% on average. Moreover, compared with when solar module equipment is not connected, there is an average 2% reduction of heat release at the time of ±50% output change of the solar module equipment.

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The plasma-wet chemical hybrid process for NOx removal from the flue gas emissions is extremely effective and economical in comparison with the conventional selective catalytic reduction system. A series of experiments using the plasma-wet chemical hybrid system are performed to control NOx from the diesel engine emission. The operation characteristics and optimum operation for plasma and chemical reactors are investigated in regard to reaction products such as N₂O, CO, CO₂, HNO₃ and NO₃^- as well as NOx removal efficiency using the pulsed corona and barrier type packed-bed plasma reactors. The oxidation from NO to NO₂ without reducing NOx concentration (i.e., minimum reaction byproducts) and with least power consumption is the key for the optimum reactor design. The produced NO₂ is totally converted to N₂ and Na₂SO₄ with Na₂SO₃ scrubbing. The hybrid reactors followed by the chemical reactor achieved extremely low operating cost and around 90% NOx removal efficiency with small amount of byproducts.

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