In this study, we adopted the Ambul technology which is a traditional knowledge of indigenous people of Kalimantan island-Indonesia to grow various crops on a floating decomposed water hyacinth on wetland ecosystem. The study was focused on the effect of water hyacinth cover on water quality and the growth of aquatic microorganism community. We also tested the utilization of water hyacinth as additional food supply for a cage cultured fish. The investigation of the effect of water hyacinth cover on water quality and the growth of aquatic microorganism community was conducted in 2 experimental ponds nearby our laboratory. One pond was treated with water hyacinth, whereas the other was kept intact without water hyacinth, as a control. Water quality in terms of phosphate, nitrate and BOD and also aquatic microorganisms particularly copepod communities were monitored at both ponds prior and after the introduction of water hyacinth. For the purpose of using water hyacinth as additional food supply for cage cultured fish, we established an experimental fish culture in water hyacinth treated and in non water hyacinth treated cages. Fish growth in terms of their weight and length were monitored for 3 months.
Our study revealed that water hyacinth effectively absorbed phosphate and reduced BOD and its cover promoted more abundant copepod community. Cultured Osphronemus gouramy fishes supplied with additional food of water hyacinth grew much faster than those cultured in non water hyacinth treated cages. Based on our results, we proposed that the adopted Ambul principle could be used as an alternative technology to overcome the organic water pollution problem both in lake and river ecosystems.

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Size-separated aerosol number concentrations and sulfate aerosols as well as rain water chemistry were simultaneously measured at Bijodaira (altitude, 977m), western slope of Mt. Tateyama, near the coast of the Japan Sea, during the autumn in 2007. The number concentrations of particles were usually higher in the daytime than in the nighttime. The sulfate particles were well correlated with the number concentrations of the fine particles. High concentrations of sulfate and the fine particles were sometimes detected. The high sulfate aerosols might have been transported from the polluted regions in the Asian continent. The trans-boundary pollutants highly affected the chemical characteristics of bulk samples rain water.

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The aim of this study was to evaluate the number of bulk deposit samplers needed to measure atmospheric deposition of pollutants with an acceptable level of variability. A set of 10 bulk deposit samplers was placed at an experimental site near Lake Biwa in the Shiga Prefecture in Japan, and water samples were collected monthly from each sampler. First, the effects of the intrusion of insects and litter were examined by placing intrusion-prevention devices on the samplers. All measures of variation (coefficient of variation [CV], skewness, and kurtosis) were smaller when the device was used than when it was not. Total nitrogen (TN) loads started to increase in April and peaked in June, with a secondary small peak in February. Levels of dissolved nitrogen, NO₃-N, and NH₄-N showed similar trends. Total phosphorus (TP) reached a maximum in May, and stayed at a relatively high level until it reached a second peak in August and September. The annual precipitation data obtained from the bulk deposit samplers were normally distributed and had an average and median value of 1570 mm yr^-1 (CV, 1.0%). Annual TN loads were also distributed normally, and their average and median values were 12.1 (CV, 2.7%) and 12.0 kg ha^-1 yr^-1, respectively. Annual TP load, however, apparently deviated from a normal distribution, and the average (0.417 kg ha^-1 yr^-1; CV, 24%) was larger than median (0.395 kg ha^-1 yr^-1). At least 8 bulk deposit samplers were needed to obtain TP loads of atmospheric deposition with a CV of less than 5%. The TN loads from the atmosphere to Lake Biwa were estimated to range from 780 to 854 t y^-1, whereas the TP load showed a much larger relative range of 20.8 to 42.9 t y^-1, indicating that more studies are needed to measure and evaluate the atmospheric deposition of phosphorus.

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The infinite dilution activity coefficients of alcohols (methanol, ethanol, 1-propanol , 2-propanol) , ethers(diethyl ether, methyl tertiary butyl ether, diisopropyl ether) and aromatic compounds(benzene, toluene, p-xylene) in aqueous solution had been correlated by the modified ASOG model previously proposed. In this paper, it is introduced that the modified ASOG can be applied to calculate the infinite dilution activity coefficients with a good correlation performance than original ASOG.

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An extended Radke-Prausnitz equation is useful in predicting the adsorption equilibria of organic multi-solute aqueous solutions on activated carbon. It has an advantage that, if the single-solute and two-solute parameters are available, the calculation of adsorption equilibria for more than three-solute systems can be carried out without additional parameters. The authors have previously proposed an empirical method for estimating the single-solute parameters using the physical properties of solutes and have obtained good prediction results for thirteen single-solute systems. In this study, the two-solute parameters of the extended Radke-Prausnitz equation had been correlated with the normal boiling point and molecular weight of solutes and the prediction performances are examined for adsorption equilibria of six two-solute, four three-solute and a four-solute aqueous solution systems. The prediction results are in good agreement with the experimental data.

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Magnesium-substituted nickel phosphates were prepared from phosphoric acid, nickel nitrate, and magnesium nitrate solutions. The obtained precipitates and their thermal products were investigated in terms of chemical composition, particle shape and size distribution, and specific surface area. The acidic properties were estimated from ammonia-temperature programmed desorption curves and the adsorption of trimethylamine. Magnesium-substituted nickel phosphates had larger specific surface areas and higher adsorption ratios of trimethylamine than did unified nickel and magnesium phosphates.

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Calcium, cobalt, manganese, calcium-cobalt, calcium-manganese, and cobalt-manganese phosphates were prepared in aqueous solution. Their chemical composition and thermal behavior of obtained phosphates were investigated by ICP, TG-DTA, XRD, and FT-IR. Specific surface area of thermal products was calculated by BET method. The removal of lead was tested with these thermal products. The relationship between the chemical composition and lead removal effects was studied.

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This study presents the measurement results of biogas production rates in an anaerobic pond of tapioca starch extraction wastewater located in Lampung province, Indonesia. The measurements were carried out in the dry and rainy seasons. The results showed biogas production rates in the range of 25.9-133.4 L/m²/h, and an average biogas production rate of 67.2 L/m²/h. Biogas production rate was affected not only by season and collection position in the lagoon, but also by time of gas collection. From the average biogas production rate in each month, the methane emission factor in pond No. 4 could be estimated at 0.16-0.31 g CH₄/g COD removed. This variation was observed due to changes in water temperature. This study showed the importance of temperature changes for the baseline measurement of greenhouse gas emissions determined by the methane emission factor in CDM projects

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