The treatment characteristics of small-scale domestic sewage treatment plants (SDSTPs), i.e., Kogata Gappei-shori Johkaso systems, using anaerobic-aerobic filter systems with flow-equalization, recirculation, and aluminum biofilter media were investigated for the purpose of simultaneous removal of BOD, Nitrogen, and Phosphorus, i.e., further improvement of effluent qualityin SDSTPs. Plant experiments were conducted under four different operating conditions. Run 1 was the control series with continuous fixed feeding and recirculation, but without aluminum biofilter media. In Runs 2, 3, and 4, the influent had two maximum flow rates (peak coefficient 6) and a feeding time of 14 hours. Run 2 was an operating series with no flow-equalization, no recirculation, and no aluminum biofilter media, and was the conventional treatment mode for SDSTPs installed in Japan. On the other hand, the SDSTP in was a novel operational mode with flow-equalization and recirculation for denitrification. In addition, the SDSTP in Run 4 had a newer operational mode with flow-equalization, recirculation, and aluminum biofilter media for both denitrification and phosphorus removal. showed a good performance for BOD and SS removals and denitrification, and the treatment efficiency in was almost the same asthat in Run 1. The SDSTP in Run 4 demonstrated the simultaneous removal of BOD, Nitrogen, and Phosphorus because of flow-equalization, recirculation, and aluminum biofilter media. In Run 4, the effluent BOD was less than 10mg⋅l^-1, and the effluent SS was less than 5mg⋅l^-1. Furthermore, the effluent nitrogen and the effluent phosphorus in Run 4 were less than 10mg⋅l^-1 and less than 1 mg⋅l^-1, respectively.

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Mesocosm experiments were conducted in the Seto Inland Sea every summer seasons from 1987 to 1989. Effects of controlled conditions on phytoplankton succession in the mesocosm were examined. One control factor was a vertical mixing method, which included a direct circulation by pumps (run 1) and a new designed circulation system (run 2 and ). In the system, vertical jet entrained the surrounding water, making soft mixing in the mesocosm. The other factor was an enrichment pattern. Nutrients were added at the surface layer in run 1 and run 2, and introduced under the mixing layer in . Phytoplankton species succession was observed every year from diatom to dinoflagellate. Red tide due to Chattonella antiqua was observed only in 1989, when the new circulation system was used and the vertical nutrient profile was set as similar to those for red tides in the field. The most important factors to control environmental conditions in mesocosms were found to be the vertical mixing power, the mixing depth, nutrient ratios (N : P : Si), and vertical distribution of nutrients.

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The characteristics of methane fermentation for treating bean-curd (tofu)-processing wastewater (BCW) containing waste bean curd frying oil were determined. To facilitate the dispersion and degradation of the oil in the wastewater, lipase and two emulsifiers were adopted. Lipase pretreatment accelerated methane fermentation. Three anaerobic digester series were continuously supplied with BCW and operated under the following conditions: Run 1, without lipase pretreatment, thermophilic methane fermentation (55°C); Run 2, with lipase pretreatment, thermophilic methane fermentation; , with lipase pretreatment, mesophilic methane fermentation (35°C). Triglycerides and long-chain fatty acids (LCFAs) were completely eliminated by lipase pretreatment in the digester (Runs 2 and 3). The calculation of mass balance demonstrated that 70% of the supplied COD_Cr in BCW was eliminated in Run 2, and that 60% of the supplied COD_Cr was converted to methane. However, only 30-40% of the supplied COD_Cr was converted to methane in or 1. The analysis of the microbial community structure in the sludge of the three digesters showed that the sulfate-reducing activity in Run 2 was lower and sulfate-reducing population was also smaller than those in Runs 1 and 3. Lipase pretreatment and thermophilic methane fermentation conditions promote the prevalence of LCFA utilizing hydrogen-producing acetogenic bacteria in the sludge of Run 2.

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The effects of urbanization on the local climate in Kanto in August 2006 were analyzed, focusing on the statistical analysis of the warmest days of this period in Tokyo. By utilizing the Weather Research and Forecasting mesoscale model (WRF), there were 8 events of sultry nights found in the simulation, when the temperature did not decrease below 25°C from late afternoon to the next morning in the WRF default; however, the number of events increased to 11 with the incorporation of anthropogenic energy (AE) and to 14 using the urban canopy model (UCM). The incorporation of AE and UCM augmented the ensemble air temperature by 0.5°C and 0.9°C, respectively, during the analysis period. Simultaneously, AE and UCM improved the accuracy of nighttime predictions, although these parameterizations tended to overestimate the real temperatures in the afternoon by up to 0.9°C. Moreover, urban parameterizations may greatly divert the wind direction, which may subsequently diminish the mixing ratio and enhance the air temperature.

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A simplified solvent extraction process based on U, Pu and Np co-recovery using tri-n-butylphosphate (TBP) as an extractant has been developed for advanced aqueous reprocessing of fast neutron reactor fuel. The influence of the HNO₃ concentration in the feed and scrubbing solutions on the behavior of Np is evaluated experimentally and found to be co-extracted into the TBP with U and Pu. Moreover, the leakage ratio of Np to the raffinate is calculated from the changes in HNO₂ concentration in the feed solution. 9.89% of the Np leaked to the raffinate in low HNO₃ concentration feed and high HNO₃ concentration scrubbing solutions. Almost all the Np in a 4.9 mol/dm³ HNO₃ feed solution is recovered with U and Pu, based on the experimental flow sheet with double scrubbing solutions of 9 and 1 mol/dm³ HNO₃. The experimental results show a large contribution from the HNO₃ concentration in the feed solution and at the extraction section to Np(V) oxidation. On the other hand, the calculation results show that high HNO₂ concentrations in the feed solution tended to leak Np into the raffinate. The DF of Cs for U, Pu and Np product achieves 10⁵ in all runs.

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Using the test tank of anchor and cable which is established at the Kobe University of Mercantile Marine, the movement of anchor and cable is showed its details through the measurement instruments. This paper is its second report which is showed stockless anchor and cable moving data ; Viz: (1) Holding pull and Dragging speed. (2) Holding pull and Dragging . () Reverse pull effect, etc.

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