In order to evaluate the feasibility of the solvent regeneration process of spent activated carbon, the spent carbon used in the adsorption treatment of an industrial wastewater and a river water was regenerated by ethanol, N, N-dimethylformamide and methanol. The regeneration efficiency was experimentally determined by batch tests and fixed-bed runs. The wastewater was supplied from a chemical factory, and contained a lot of aromatic compounds. Its total organic carbon concentration (TOC) was around 0.11-0.13kg/m³. The river water was pumped out from the Takano River or the Uji River in Kyoto Prefecture. The influence of repeating regenerations on the regeneration efficiency was experimentally determined. The efficiency obtained was high, and the adsorption capacity of regenerated carbon did not decreased greatly after the repetition of regeneration. The elution curves of adsorbate were experimentally determined, and the results showed that the adsorbate desorbed from the carbon could be concentrated to the solvent. Economics of activated carbon regeneration was evaluated. It was found that the solvent regeneration was economically more attractive than the thermal regeneration.

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As evaluation of the amenity level of the environment is very subjective, it is impossible to measure the level through such common scales as environmental standards. The physical state of the amenity factors are also impossible to be measured. The study tried to quantify the amenity level of the environment through th five senses of people. We developed environmental observation indicators which are based on citizens' observation on their environment. An environmental observation survey was conducted for elementary school pupils and their parents in Kawasaki City. The survey was conducted through all of the 111 elementary schools in the city. About 3800 samples were collected by the survey. The pupils were asked to observe the natural environment and the parents were asked to observe and evaluate the amenity level of the urban environment. The followings were found by the study. Firstly, the rates of finding such small animals as beatles and snakes are strongly related to the evaluation of the amenity level. Secondly, the two evaluation items of?etownscape?fand?egreenery?fsupposed to become good indicators by citizens' observation from the analysis of the parents survey data. The two items strongly contribute to the comprehensive evaluation of the amenity level. Thirdly, the air quality and noise levels which have been measured by equipments are also pertinently grasped by observation. Lastly, amenity has the biggest contribution to the comprehensive evaluation of the urban environment among six items of safety, health, convenience, amenity, district identity and community human relationship.

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Veratrole and guaiacol were chosen as the model compound of the aromatic moieties of lignin and the mechanisms in degradations of them were proposed. In order to elucidate the mechanism of wastewater by ozonolysis, the wastewater was compared with the model compound using several indexes which were measured by the experiments. The experimental data which were used as the indexes were absorbance of 280 nm and absorbance of 280 nm after reduction by hydrogen, amounts of methoxyl, phenolic hydroxyl and oxalic acid. In the ozonolysis of wastewater, absorbance of 280 nm and amount of oxalic acid were lower than that of model compound to some extent, but other indexes were in agreement each other. Experimental results confirmed that the mechanism of model compound was in agreement with that of wastewater.

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The effect of NO₂, one of the most important environmental factors in the conservation of cultural properties, was investigated with respect to the fading of dyed fabrics. Ambient NO₂ concentrations at 19 sites in museums and galleries were measured by a passive sampler on a monthly average basis for one year. It was found that the annual average concentration ranged between 20-60 ppb at the outdoors, 7-20 ppb in the exhibition rooms and 2-7 ppb in the showcases. Airconditioning, especially with a charcoal filter, was found to be effective in controlling ambient NO₂ concentration. Aclosed environmental system such as a Japanese traditional warehouse is also good for minimizing low NO₂ concentration. Fading-test pieces dyed by brazilin, Chinese tannin, purpurin and myricetin, all selected from Japanese traditional dyestuffs, were exposed to the museum and gallery environment for one year. As a result of dese-response characterization, The correlations between NO₂ dose and color difference were found to be fairly good for all of the dyestuffs tested here. Moreover, a substrate effect was clearly observed that the cotton piece was faded more than the silk one. It is considered that it occurred due to the oxidation of the dyestuff by NO₂. In addition, hydrolysis might occur due to the acidity of NO₂in the case of Chinese tannin.

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