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Adverse effects of future climate change on water supply systems are of concern. High turbidity caused by abrupt flood, and drought caused by continuous dry days are the major risks. To assess such risks, a comprehensive method to simulate hydrology with high spatiotemporal resolution should be developed. In this study, a series of methods from parameter estimation to future simulation using the Soil and Water Assessment Tool (SWAT) was demonstrated for Sagami Dam reservoir, which is a typical water supply reservoir in Japan. A proposed parameter calibration method by optimizing percent bias followed by optimizing Nash–Sutcliffe efficiency gave good performance of model prediction of the daily average reservoir inflow in the past. Using this model, the changes in inflow under expected climate change were simulated. Three predicted daily climates by the Model for Interdisciplinary Research on Climate version 5 (MIROC5) under three representative concentration pathways, i.e., RCP 2.6, 4.5, and 8.5, in 2081–2100 were used for the simulation, whereas observed daily climate during 1981–2000 was used as the past reference. The risks were discussed by considering their seasonality, indicating increases in flood and drought in June and July, and in February and April, respectively.

The status of water consumption and preparedness for water outages at intensive care homes for the elderly (ICHE) in Japan was investigated by questionnaire. The ICHE is the nursing care facilities covered by public aid providing long-term care for the elderly in Japan. The daily water consumption per person admitted to the ICHE was estimated as 425 L (median) and the daily water consumption per admitted elderly person and the contributors (i.e., care staff and visitors) was estimated as 253 L (median). The question from the viewpoint of alternative water supply revealed a high rate of possessing water receiving tanks. In addition, the possession rate of personal wells was also clarified. High rates of drinking water storage and portable toilets were confirmed. From the viewpoint of action procedures, the rates of introduction of disaster training, disaster action manual, and mutual aid agreement in the event of a disaster with others, all of which took into consideration water outages, were also clarified. Furthermore, free written comments confirmed that many ICHE were concerned about toilet care in the event of an emergency.

ObjectiveTo examine the possibility of diagnosing the double burden of malnutrition using estimated deviation values in low- and lower-middle-income countries.MethodsA modified version of the Japanese Diagnostic Tool was used. Data on 194 countries were analyzed, including data from the United Nations International Children's Fund, World Health Organization and World Bank. After conducting a Box-Cox transformation, deviation values were calculated. The degree to which the values deviated relative to a deviation cutoff value of 50 was assessed. Focusing on countries with low- and middle-income economic levels, we examined the utility of this tool to show characteristic nutritional problems in each country.ResultsThe deviation values had normal, distorted, bimodal, or trimodal distributions. In the lower-middle-income countries, almost all countries had values ranging from 40 to 60 for education and water environments (urban and rural), and the differences were minimal. However, different causes of noncommunicable disease-related deaths were considered, and the primary cause appeared to be related to lifestyle factors, particularly alcohol consumption and tobacco smoking. In comparison, the deviation values related to death among low-income countries also appeared to be related to differences in education and sanitation in urban and rural areas.ConclusionThe study results can help to determine the status of nutritional inequalities and plan country-specific strategies to reduce the double burden of malnutrition.

Rice paddy water management was integrated into a distributed three-dimensional surface and subsurface coupling hydrological model of the Sakuragawa River watershed. This watershed is located in the Kanto Plain in Japan and includes the hillside of Mt. Tsukuba. Therefore, this watershed includes both steep mountainous areas and rice paddy-dominated flat land. Thus, water management of rice paddies is important and was calculated separately using a paddy model. The use of groundwater for rice paddy irrigation was considered as well as a water supply from outside of the watershed (Kasumigaura Lake). The model parameters were calibrated and validated with reference to the predictability of river water flow and the groundwater level. Using the calibrated model, three-dimensional streamlines, water travel time distributions, and water balance in some grids were clarified. The developed model will facilitate sustainable water resource management in the watershed.

Recent trends in off-flavor problems were investigated by a nationwide questionnaire survey targeting 239 drinking water treatment plants (DWTPs) maintained by 79 regional water suppliers (RWS) in Japan. The results indicated that 43 of 79 (54%) RWS and 89 of 239 (36%) DWTP were affected by off-flavor problems in a recent 2-year period (October 2010–September 2012). Off-flavor incidents occurred in all regions in Japan. Most DWTPs affected by off-flavor incidents take in water from closed water areas, such as dams and lakes, where phototrophic microorganisms, such as cyanobacteria and algae, can grow easily. The most common off-flavor was an earthy–musty odor, while a fishy smell was also reported in some cases. The common producers of geosmin were Anabaena spp., while those responsible for 2-methylisoborneol were Phormidium spp. and Oscillatoria spp. The off-flavor events frequently occurred during summer and early fall months (June–September). The water temperature and pH of raw water for the production of drinking water when off-flavor problems occurred were higher than those during normal periods. To eliminate off-flavor compounds, most DWTPs (about 58%) adopt powdered-activated carbon treatment, which considerably increases operational costs.

Livestock wastewater disposal onto rice paddy fields is a cost- and labor-effective way to treat wastewater and cultivate rice crops. We evaluated the influence of nitrogen loading rates on nitrogen assimilation by rice plants and on nitrogen losses (leaching and N2O emission) in forage rice fields receiving liquid cattle waste (LCW). Four forage rice fields were subjected to nitrogen loads of 107, 258, 522, and 786 kg N ha−1 (N100, N250, N500, and N750, respectively) using basal fertilizer (chemical fertilizer) (50 kg N ha−1) and three LCW topdressings (each 57–284 kg N ha−1). Nitrogen assimilated by rice plants increased over time. However, after the third topdressing, the nitrogen content of the biomass did not increase in any treatment. Harvested aboveground biomass contained 93, 60, 33, and 31 % of applied nitrogen in N100, N250, N500, and N750, respectively. The NH4 + concentration in the pore water at a depth of 20 cm was less than 1 mg N L−1 in N100, N250, and N500 throughout the cultivation period, while the NH4 + concentration in N750 increased to 3 mg N L−1 after the third topdressing. Cumulative N2O emissions ranged from −0.042 to 2.39 kg N ha−1; the highest value was observed in N750, followed by N500. In N750, N2O emitted during the final drainage accounted for 80 % of cumulative N2O emissions. This study suggested that 100–258 kg N ha−1 is a recommended nitrogen loading rate for nitrogen recovery by rice plants without negative environmental impacts such as groundwater pollution and N2O emission.

To evaluate global warming potential (GWP) on livestock waste treatment and biomass production in rice field, methane (CH4) and nitrous oxide (N2O) fluxes from forage rice fields planted with 4 different cultivars (Oryza sativa L. cv. Hamasari, Leafstar, Kusahonami and Takanari) were measured. Each of the cultivars were subjected either to basal fertilization alone (control plots) (84 kg N ha− 1), or to basal fertilization plus topdressing with liquid cattle waste or LCW (treatment plots) (567 kg N ha− 1). Liquid cattle waste application to the rice field resulted in peak CH4 fluxes ranging from 22.0 to 32.1 mg m− 1 h− 1 during flooded conditions and large N2O fluxes ranging from 526 to 8591 μg m− 1 h− 1 after midsummer drainage and final drainage. The GWP of the control plots was between 1358 and 3872 kg CO2eq ha− 1, while the treatment plots ranged between 4503 and 8426 kg CO2eq ha− 1 and more than 60% of the GWP was from the N2O emission in treatment plots. In both the control and treatment plots, the lowest GWPs per ton of above-ground biomass were found to be from the Leafstar cultivar, which had a higher aboveground biomass than other cultivars; 117 kg CO2eq t− 1 from the control and 257 kg CO2eq t− 1 from the treatment plots. Thus, both forage production and suitable disposal of the LCW may be able to be achieved concomitantly with lower levels of GWP by cultivation of Leafstar in our field.

The assessment of benzene emissions from a soil to the atmosphere is important for the preservation of human health and the management of contaminated soils. The adequacy of a simple numerical model, assuming two-phase diffusion and linear equilibrium of liquid-solid adsorption, was investigated by comparing the changes in benzene concentration in an Andosol with predicted benzene flux in a flux chamber. Different initial benzene concentrations were applied to the soil with a water content of 25 kg kg -1 to determine the liquid phase adsorption coefficient (K D ), which was ultimately determined to have an optimum value of 1.29 mm 3 kg - 1 . In addition, the influence of varying water contents on benzene transport was investigated using the soil samples but with different initial water contents (10, 25, and 40 kg kg -1 ) and at a fixed initial benzene concentration (50 mg kg -1 ). The results showed that the simple model adequately predicted benzene transport in soil for a period of

Flooded paddy fields perform many ecological and conservation functions and are also reported to facilitate livestock waste disposal. Paddy field infiltration rates are important for nitrogen dynamics. A laboratory study was conducted to compare the effects of infiltration rate on nitrogen dynamics including nitrogen leaching, soil adsorption, microorganism assimilation, plant uptake and denitrification. Two infiltration rates were applied to paddy soil: 18.6 ± 10.3 mm d −1 (High Infiltration Columns: HIC) and 4.49 ± 3.15 mm d −1 (Low Infiltration Columns: LIC). Total nitrogen load was 484 kg-N ha −1 , with the ammonium ion form including basal fertilizer and a double supplemental fertilizer application. A ( 15 NH 4 ) 2 SO 4 tracer was applied in each infiltration rate as supplemental fertilizer. Nitrification and denitrification, plant uptake, soil adsorption, and leaching differed between infiltration rates. Compared with high nitrate concentration in HIC soil water, little nitrate appeared in the LIC, and it maintained relatively higher soil water ammonium concentrations long after application. The 15 N assimilated by rice and contained in the LIC soil was higher than in the HIC, suggesting that low infiltration is beneficial to nitrogen assimilation, adsorption and fixation. Although loss of nitrogen via leaching was higher in the HIC than the LIC, it accounted for only 3.94% of total 15 N input. About 69.4% of total 15 N input was unaccounted for in the HIC, whereas 38.3% of total 15 N input was unaccounted for in the LIC. According to the denitrification rate calculated from changes in 29 N 2 / 28 N 2 and 30 N 2 / 28 N 2 ratios, the denitrification rate after HIC application was higher than the LIC, reaching a maximum rate of 2.9 g m −2 d −1 . This suggests that high infiltration rate enhances nitrification and denitrification, with most of the unaccounted inputted 15 N in the HIC was probably lost through nitrification and denitrification.

For developing a multipurpose Botryococcus braunii utilization system, in which water purification and biofuel production will be achieved simultaneously, the growth behavior of B. braunii under a simulated open-air condition was clarified, where Microcystis aeruginosa was assumed to coexist. Microcystis aeruginosa is one of the typical algae in eutrophic water. The monoculture experiments revealed that the growth rate of a B. braunii strain was lower than that of a microcystin-producing M. aeruginosa strain under various phosphate concentrations. Meanwhile, the phosphate uptake rate of B. braunii was higher than that of M. aeruginosa. In the batch monoculture experiments, the promising hydrocarbon production of B. braunii was observed within a wide range of initial phosphate concentrations (11 to 216 mg-PO43-/L). In the two-algal species mixed culture experiments, the growth characteristics were different with the coexisting species. When a non-microcystin-producing M. aeruginosa strain was cultured with B. braunii, the domination of M. aeruginosa within the experimental period was observed especially in the cases where the initial biomasses of M. aeruginosa were high compared to those of B. braunii. On the other hand, when microcystin-producing M. aeruginosa was cultured with B. braunii, the abundant microcystin production was observed without domination of M. aeruginosa. These results suggested the importance of the effective utilization of the high phosphate uptake ability of B. braunii, and the control of the initial biomass ratio of algae for the realization of B. braunii system under the open-air condition.

Giant reed has high biomass productivity, and is a promising plant to be used for a constructed wetland system in which energy/material production and water purification are achieved simultaneously (multi-functional wetland). In this study, the cadmium removal by hydroponically cultured giant reed was observed, and its concentration in the plant body was measured to clarify the applicability of the wetland for cadmium treatment. The results suggested that the hydroponic culture of giant reed has high potential for cadmium removal. In addition, the inhibitory effect of cadmium on phosphorus removal, that is also important for water purification, was not observed under a concentration lower than 1 mg-Cd/L for 7 days. After about 2 months of hydroponic culture the absorbed cadmium was highly concentrated in the rhizome. Furthermore, the positive correlation between glutathione (GSH) in the rhizome and cadmium removal rate was observed, indicating that the production of GSH was controlled by the cadmium assimilated in the giant reed.

Freshwater shortage and energy crisis are the two major challenges in the 21st century. The coupling of wastewater treatment and energy production to supply reclaimed water and sustainable energy is a very promising approach to handle these two challenges. A novel process of domestic wastewater reclamation coupled with biofuel/biomass production based on microalgae is proposed in this paper. The organic pollutants in wastewater are separated and concentrated by flocculation and filtration, and nitrogen and phosphorus are used as nutrients for microalgal cultivation. The organics separated and microalgal biomass harvested can be further processed to produce biofuel. The novel process proposed in this paper will bring about innovation in wastewater treatment, and the conventional wastewater treatment process will be transformed from a mere "treatment process" to a "production process" using wastes as raw materials and thereby can produce biofuel and other valuable by-products. At present, this novel process is in the conceptual stage, and some key techniques necessary to be further studied are also discussed in this paper.

Giant reed (Arundo donax) is a perennial, gramineous plant that has high biomass production potential. In this study, we focused on its applicability as a raw material for the production of adsorbents for the purification of cadmium-contaminated water. Charcoals were prepared from the stalk of the giant reed at various temperatures (400 - 700°C) under nitrogen stream. Analysis of pore size distribution based on methanol vapor adsorption revealed that the mesopores within the range of 20 to 100 A were abundant in charcoals prepared under 400°C and 500°C. Using these charcoals, the removal capacity of cadmium from aqueous solution was investigated. As a result, high removal capacity under low concentration of cadmium was observed. High yield of cadmium with 0.01 N hydrochloric acid treatment was also clarified. X-ray diffraction (XRD) analysis revealed that Cd(OH)2 existed on the surface of the cadmium-adsorbed charcoal. The possible mechanism of the "apparent adsorption" was discussed.

In recent years, the exploration and development of the effective methods of treatment and prevention to algal blooms, especially Microcystis aeruginosa blooms has been an important issue in the field of water environment protection. Allelochemicals (natural plant toxins) are considered promising sources of algicides to control algal blooms. The objective of this study is to determine the inhibitory effects and potential mechanisms of a well-known allelochemical gramine (N,N-dimethyl-3-amino-methylindole) on bloom-forming cyanobacterium M. aeruginosa. The results showed that this indole alkaloid effectively inhibited the growth of M. aeruginosa. The effective concentration causing a 50% inhibition at 3 d (EC(50, 3 d)) increased with the initial algal density (IAD) increasing. When IAD increased from 5x10(4) to 5x10(5)cellsmL(-1), the values of EC(50, 3 d) increased from 0.5 to 2.1mgL(-1). In the cells of M. aeruginosa, gramine caused an obvious increase in the level of reactive oxygen species (ROS). The lipid-peroxidation product malondialdehyde (MDA) increased significantly in gramine-treated cells. The effects of gramine on enzymatic and non-enzymatic antioxidants were in different manners. The activity of superoxide dismutase (SOD) was decreased after gramine exposure. The catalase (CAT) activity was increased after 4h but decreased from 60h. Both the contents and the regeneration rates of ascorbic acid (AsA) and reduced glutathione (GSH) were increased after 4h of exposure to gramine. However, only GSH content was still increased after 40h of exposure. These results suggested that the activation of antioxidants in M. aeruginosa played an important role to resist the stress from gramine at initial time, the inactivation of SOD is crucial to the growth inhibition of M. aeruginosa by gramine, and the phytotoxicity of gramine on M. aeruginosa may be due to oxidative damage via oxidation of ROS.

Macrophyte-cultivated wetlands have a strong potential not only to purify eutrophic water but also to produce biomass resources. Among a variety of macrophytes, we focused on the giant reed (Arundo donax), and its properties of phosphorus uptake, accumulation, and translocation were clarified in this study. Phosphorus uptake experiments using outdoor hydroponic culturing showed the seasonal variation of phosphorus uptake by the giant reed. Furthermore, two kinetic parameters describing the phosphorus uptake by the giant reed were obtained. Phosphorus accumulation experiments using radioactive phosphorus suggested that giant reeds accumulate the absorbed phosphorus in rhizomes, and it is then distributed to the leaves if needed. A phosphorus translocation experiment using radioactive phosphorus indicated that the decreasing of phosphorus in the leaves occurred in the order of location from the bottom to the top, which is relevant to the order of dying down of the plant leaves actually observed in this study. Based on these outcomes, a desirable management method for the giant reed cultivated in wetlands is proposed.

Forage rice has high potential to produce biomass, and the vertical flow (VF) constructed wetland in which forage rice is cultivated is one of the effective ways to achieve the purification of eutrophicated water and biomass production simultaneously. To design and manage the VF constructed wetlands cultivated with forage rice adequately, nutrient dynamics and the growth of the rice should be understood quantitatively. In this study, we performed a series of experiments replicating VF constructed wetlands involving the cultivation of a variety of forage rice ("Kusahonami") using river water (supply rate : 0.1, 0.2, and 0.6 m3/(m2·day)) for 169 days. The results showed that the rice biomass increased with the river water supply rate. A mathematical model was developed based on these experimental observations in order to quantitatively explain the nitrogen dynamics in VF constructed wetlands cultivated with forage rice. The changes in both the rate of nitrogen assimilation by rice and the denitrification rate with the change in the rate of water supply were simulated with the proposed model.

Ethyl t-butyl ether (ETBE) is a widely used gasoline additive known to be a persistent chemical substance. In this research, the mechanism of the degradation of ETBE by sodium persulfate was investigated. The sodium persulfate treatment of ETBE revealed that 100% ETBE in aqueous phase was degraded within 79 h. The degradation of ETBE followed a pseudo-first-order reaction and its degradation rate constant was 0.054 h-1. The identification of byproducts in both aqueous and gas phases by GC-FID and GC-TCD revealed that acetaldehyde, ethanol, acetone, t-butyl alcohol (TBA), acetic acid, t-butyl acetate, CO2 and CH4 were generated during the reaction. 95% of the carbon in the degraded ETBE was recovered in the form of these byproducts. The degradation of each byproduct was carried out to determine the degradation pathways of ETBE by sodium persulfate. Consequently, the degradation pathways are proposed as follows: the main pathway in the initial stage is (i) ETBE → TBA + ethanol, and the subpathway is (ii) ETBE → t-butyl acetate. Further degradation pathways are proposed as follows: ethanol → acetaldehyde → acetic acid, TBA → acetone → acetic acid, t-butyl acetate → TBA + acetic acid and acetic acid → CO2.

The separation of valuable chemicals from raw products, where a great number of chemicals coexist, is the key technology in biomass refinery. In this study, the applicability of membrane separation of valuable chemicals from our currently developed portable superheated steam (SHS) biomass pyrolysis process was demonstrated. Phenols (phenol, p-cresol, guaiacol, methyl guaiacol, and ethyl guaiacol), furfural, and acetone were successfully separated by pervaporation using the silicone rubber membrane from model solutions and an actual SHS derived aqueous solution. The solution was also concentrated effectively by reverse osmosis separation using a polyamide membrane. When a high concentration of SHS solution was fed to the pervaporation process, a phase-separated permeate was obtained, which indicated that the reverse osmosis concentration combined with pervaporation separation is useful for the superheated steam process.

The use of liquid cattle waste (LCW) as a fertilizer for forage rice is important for material recycling because it can promote biomass production, and reduce the use of chemical fertilizer. Meanwhile, increase in emission of greenhouse gases (GHGs), especially CH 4 and N 2 O would be concerned. We conducted a field study to determine the optimum loading rate of LCW as N to promote forage rice growth with lower GHG emissions. The LCW was applied to forage rice fields, N100, N250, N500, and N750, at four different N loading rates of 107, 258, 522, and 786 kg N ha −1 , respectively, including 50 kg N ha −1 of basal chemical fertilizer. The above-ground biomass yields increased 14.6–18.5 t ha −1 with increases in N loading rates. During the cultivation period, both the CH 4 and N 2 O fluxes increased with increases in LCW loading rates. In the treatments of N100, N250, N500, and N750, the cumulative CH 4 emissions during the entire period, including cultivation and fallow period were 29.6, 18.1, 54.4, and 67.5 kg C ha −1 , respectively, whereas those of N 2 O were −0.15, −0.02, 1.49, and 5.82 kg N ha −1 , respectively. Considering the greenhouse gas emissions and above-ground biomass, the yield-scaled CO 2 -equivalents (CO 2 -eqs) were 66.3, 35.9, 161, and 272 kg CO 2 t −1 for N100, N250, N500, and N750, respectively. These results suggest that N250 is the most appropriate LCW loading rate for promoting forage rice production with lower GHG emissions.

We report on a 20–40 s process for growing aligned, uniformed, high purity multi-walled carbon nanotubes (MWNTs) using an alcohol lamp burner. With an appropriate catalyst precursor concentration, MWNTs can be grown on a Co-coated 304 stainless steel mesh under incomplete combustion conditions at 680–700°C. The process provides a rapid, easy, economic and safe method for the formation of carbon nanotubes. We suggest that the proposed method be considered as an educational kit for college or high school level experiments.

To develop a novel noncatalytic biomass refinery process that can be used as a portable process, superheated steam pyrolysis was investigated to produce both carbonized solid fuels and chemicals using a large-scale reactor. Individual biomass components and native biomass (Sugi, Japanese cedar) were pyrolyzed. Between 150 and 400 degrees C, the vaporizing fractions of cellulose, xylan, and kraft lignin were summarized using a numerical model. Cellulose was converted to glycolaldehyde, furfural, 5-hydroxymethyl furfural and levoglucosan, whereas xylan was converted to glycolaldehyde, furfural, and acetic acid. Kraft lignin produced a slight yield of phenol and guaiacol. The total vaporization fraction of Sugi and its vaporizing rate were explained sufficiently using a numerical model based on the weighted average of the vaporizing properties of the individual components. However, the yields of phenol, guaiacol, and acetic acid were underestimated, while the yields of furfurals and levoglucosan were overestimated. Possible synergetic effects among chemicals in the superheated steam pyrolysis of native biomass were also discussed.

Elution of Japanese cedar pollen allergens (Cry j I and others) from pollen grains and its adsorptive concentration onto hydrophobic and hydrophilic surfaces were investigated using the surface plasmon resonance technique. Results showed that the allergen elution was obviously enhanced when the ion concentration was higher than that within the human body, indicating that the pollen tend to release its allergen in environmental water having a high ion concentration. However, higher adsorption capacity was observed on hydrophobic surface than hydrophilic surface. These results indicate that water puddles on roadsides beside heavy traffic including large amounts of ion compounds and hydrophobic diesel exhaust particles (DEPs) are a pollen allergen-DEP complex generator. DEPs are easily absorbed into the living body; therefore these mechanisms may be responsible for causing the highest incidence of pollinosis among residents living alongside roads with heavy automobile traffic.

This work elucidates the applicability of our newly developed adsorptive ozonation process for the decomposition of 2-methylisoborneol (MIB), a typical taste and odor chemical, without the formation of possibly carcinogenic bromate ions. First, zeolite adsorbents were screened for their ability to adsorb MIB with a batch-type adsorption experimental apparatus and a flow-type decomposition experimental apparatus included an adsorbent-packed column. The USY zeolite with the highest silica to alumina ratio (SiO(2)/Al(2)O(3) molar ratio=70) showed the best performance as an adsorbent. Using this adsorbent, an ozonation experiment on an MIB solution including bromide ions was performed under various retention times using the flow-type apparatus. As a result, sufficient decomposition of MIB was achieved with preventing bromate formation.

We have developed activated carbon membranes (ACM) that can remove not only particulate matters but also dissolved organic matters. Recently, we succeeded in growing carbon whiskers on activated carbon membranes (W-ACM). We hypothesize that the whiskers prevent the flux from lowering due to particle blocking on the membrane surface. In this study, we compared the filtration properties and blocking characteristics of ACM and W-ACM using an artificial microsphere (polymethyl methacrylate) (PMMA), particle diameter = 0.8, 5, and 10 μm) to estimate the effect of whiskers on particle filtration. We found that the whiskers successfully prevented a reduction of penetration flux in all particle diameters; however, the prevention mechanism seems to be different according to the filtrated particle size. To clarify the mechanism, we performed numerical model analysis using a microfiltration model. In the case of 0.8 μm particle filtration, whiskers seemed to inhibit the packing of particles into the microholes existing at the surface of activated carbon membrane, and with 5–10 μm particle filtration, the packing density of the cake layer accumulated on the membrane would be reduced with the appearance of whiskers.

バイオマスやセルロースの熱分解によって得られるヒドロキシメチルフルフラール (HMF) を原料としてポリエステルの合成を行った. HMFを還元して得られるビスヒドロキシメチルフラン (BHF) を天然のジカルボン酸であるコハク酸, フマル酸, マレイン酸と重縮合を行ってポリエステルを合成した. 重縮合は, 酸クロリドを用いる方法と縮合剤を用いる方法により行った. 縮合剤を用いて合成したBHFとコハク酸とのポリエステルの数平均重合度は最高30のものが得られ, NMRおよびIRスペクトルから直鎖状の規則性ポリマーであることがわかった. また, 2種類のジカルボン酸を混合してBHFと重縮合を行って, 共重合体を合成した. 得られたポリエステルのDSC測定から, ポリエステルの融点とガラス転移点を求めた.

Competition for raw materials between sugar and ethanol usually occurs when biomass ethanol is produced from sugarcane. In order to overcome this critical problem, numerous studies have investigated the production of ethanol from two by-products of sugarcane: molasses and bagasse. However, there have been no previous attempts to improve the relevant properties of sugarcane, such as its growth rate, sugar content or fiber content.The objective of the current work was to develop a novel system for high-yield biomass ethanol production to support existing methods of sugar production. A system for the simultaneous production of sugar and biomass ethanol was designed by employing selected sugarcane strains that were developed specifically for this process, including 95GA-24, 95GA-27 and NiTn18.We ran productivity simulations using data from the novel sugarcane strains and compared the per-formance of the new process with that of conventional methods. Our results confirmed that sugar produc-tion could be maintained at present levels while three-times more biomass ethanol could be generated com-pared with the conventional processes. In addition, we demonstrated that a carbon-neutral process could be achieved using the new system.

The objectives of this work are to propose a novel ozonation process in adsorption phase using high silica zeolites and elucidate its advantages for simultaneous achievement of prevention of bromate formation and sufficiently high ozonation performance. Bromate is formed from bromide during ozonation under conventional conditions and needs to be reduced at least below a regulated concentration because of its considerable carcinogenicity. The ozonation of 2-methylisoborneol (2-MIB), a model Taste and Odor (T&O) chemical, has been studied in our process. It was known that 2-MIB is adsorbed onto high silica zeolite and oxidized with ozone rapidly in micropores. An adsorbent, named US-Y, in which the SiO2/Al2O3 ratio is 70, was the best candidate in this study in terms of adsorption of 2-MIB, decomposition of 2-MIB and prevention of bromate formation. Actually, bromate formation was not detected, while about seventy five percent of 2-MIB was decomposed with extremely low ozone concentration of 0.07 ppm and short retention time of 0.2 min in the presence of US-Y. Its applicability for the treatment of natural water containing natural organic matters (NOMs) was also demonstrated.

To estimate the long-term effects of ecosystem-manipulating lake restoration methods such as biomanipulation, we need a numerical model which can predict the succession of plankton community with sufficient accuracy. An accurate numerical model can be prepared based on an accurate data background. In this sense, two series of mesocosm (outdoor open-air pond) experiments that mimicked conditions in shallow and eutrophic water ecosystem were performed to clarify the effects of the zooplankton community on phytoplankton succession quantitatively. The experiments were carried out in both summer and winter periods. The results revealed that three types of zooplankton, namely rotifers, copepods, and cladocerans, have different effects on phytoplankton succession. Rotifers did not graze blue-green algae. Cladocerans suppress the growth of phytoplankton even for some blue-green algae effectively by their predation. The results of these experiments suggest that the amount of crustaceans, i.e., copepods and cladocerans, should be increased for the successful enforcement of biomanipulation. A model based on these quantitative outcomes, and its prediction of a biomanipulation for an eutrophic shallow lake is also mentioned.

A numerical model describing the penetration of petroleum oil into sandy beach sediments was developed to assess the behavior of stranded oil at tidal zone as a result of tanker accidents, and so on. To understand the penetration behavior, penetration rate of three species of petroleum oil (two species of fuel oil C and one species of crude oil) was observed experimentally with artificial tidal zone equipment. As a consequence, two types of oil were distinguished from the viewpoint of penetration rate. One (fuel oil C-1) kept its homogeneity in composition and showed relatively rapid penetration, the other (fuel oil C-2 and crude oil) became heterogeneous and slow in penetration. Considering this aspect as the adsorption of the polar compounds (i.e. asphaltenes) on the sediment surface, a numerical model that described oil penetration into sandy beach was developed. As a result, the difference in penetration rate between these two types of oil could not be replicated sufficiently only by consideration of the adsorption. However, the change of a parameter value which represents the apparent viscosity of oil led to good agreement with observations. Simulation results indicated that when fuel oil C or crude oil used in this study was stranded at a sandy beach located in Hiroshima Bay, Japan, 2 to 39% of total stranded oil might penetrate into the deeper zone (>3 cm in depth) over 50 days.

A novel composite membrane consisting of an activated carbon membrane with filamentous carbon, applicable to water treatment, was fabricated by a combination of conventional carbonization and thermal deposition. The carbonization was performed after dipping a ceramic support in a latex polymer followed by the application of ferric sulfate [Fe 2 (SO 4 ) 3 · n H 2 O] catalyst. This was followed by CVD from methane at 1050–1100 °C. The resulting membrane therefore consisted of a filamentous carbon layer grown with a combination of the catalyst and deposited hydrocarbon, and an activated carbon layer on a ceramic support. These structural characteristics were confirmed by means of the cut-off of dextran molecules, the pure water permeability, SEM, and the adsorption of phenol. Water treatment experiments using phenol and poly(methyl methacrylate) as model pollutants indicated that this membrane was able to remove dissolved organics of low molecular weight and suspended solids. Also, the filamentous carbon layer successfully prevented the fine particles from sticking on the external surface of the membrane by frequent back washing.

Livestock wastewater disposal onto rice paddy fields is a cost- and labor-effective way to treat wastewater and cultivate rice crops. We evaluated the influence of nitrogen loading rates on nitrogen assimilation by rice plants and on nitrogen losses (leaching and N2O emission) in forage rice fields receiving liquid cattle waste (LCW). Four forage rice fields were subjected to nitrogen loads of 107, 258, 522, and 786 kg N ha(-1) (N100, N250, N500, and N750, respectively) using basal fertilizer (chemical fertilizer) (50 kg N ha(-1)) and three LCW topdressings (each 57-284 kg N ha(-1)). Nitrogen assimilated by rice plants increased over time. However, after the third topdressing, the nitrogen content of the biomass did not increase in any treatment. Harvested aboveground biomass contained 93, 60, 33, and 31 % of applied nitrogen in N100, N250, N500, and N750, respectively. The NH4 (+) concentration in the pore water at a depth of 20 cm was less than 1 mg N L(-1) in N100, N250, and N500 throughout the cultivation period, while the NH4 (+) concentration in N750 increased to 3 mg N L(-1) after the third topdressing. Cumulative N2O emissions ranged from -0.042 to 2.39 kg N ha(-1); the highest value was observed in N750, followed by N500. In N750, N2O emitted during the final drainage accounted for 80 % of cumulative N2O emissions. This study suggested that 100-258 kg N ha(-1) is a recommended nitrogen loading rate for nitrogen recovery by rice plants without negative environmental impacts such as groundwater pollution and N2O emission.

A structural dynamic model describing a shallow, eutrophic water ecosystem is proposed in this paper. This type of model is useful for predicting the effects of biomanipulation. Various examples of this kind of model have been suggested in previous reports. The next salient issue demanding attention would be calibrating such models on the basis of more rigid data. In this paper, some of model parameters were calibrated and validated on the basis of observations of a mesocosm. In the mesocosm, almost complete material balances can be measured; these allow for the control of important factors in such systems. Hence, mesocosm observations were used in the calibration of parameters. The calibrated model was strongly supported on the basis of other observations of the mesocosm. The simulation study used in the proposed model indicated that the effects of biomanipulation on algal growth suppression differs depending on their zooplankton composition.

The algal growth in the Tsukui Reservoir, one of the typical eutrophicated reservoir in Japan, was modeled numerically with considering the water flow dynamics in the reservoir. After evaluating the predictability of the model, we simulate the operation of the in situ algal filtration method. The results suggested that there are non-linear relationships between the filtration rate and algal growth, or material recovery. The optimum operation condition of the in situ algal filtration method which removes 50% of algae in the Tsukui Reservoir was calculated as 106 · m3 · day-1∼107m3 · day-1.

In this study, we focused on water quality in an urban canal and the Mekong River in the city of Can Tho, a central municipality of the Mekong Delta region, southern Vietnam. Water temperature, pH, electrical conductivity, BOD5, CODCr, Na+, Cl−, NH4 +−N, SO4 2−−S, NO3 −−N, and NO2 −−N for both canal and river, and tide level of the urban canal, were monitored once per month from May 2010 to April 2012. The urban canal is subject to severe anthropogenic contamination, owing to poor sewage treatment. In general, water quality in the canal exhibited strong tidal variation, poorer at lower tides and better at higher tides. Some anomalies were observed, with degraded water quality under some high-tide conditions. These were associated with flow from the upstream residential area. Therefore, it was concluded that water quality in the urban canal changed with a balance between dilution effects and extent of contaminant supply, both driven by tidal fluctuations in the Mekong River.

Algae (Selenastrumn capricornutum and Micocystis aeruginosa) were cultivated in the condition of coexistence with various amounts of macrophyte to evaluate the inhibitory effect of macrophyte on algal growth. The effect of water extract and methanol extract from macrophyte on algal growth also was investigated. Egeria densa, Cabomba caroliniana and Myriophyllum spicatum were used as macrophyte. As the macrophyte increased in the algae-macrophyte mixed culture system, algal growth was reduced. It was also shown that the water extract and methanol extract inhibited algal growth and that the inhibitory effect of macrophyte were species-specific to algae. EC50 of macrophyte, water extract and methanol extract for algal growth showed that Myriophyllum spicatum had the most inhibitory effect on the growth of both S. capricornutum and M. aeruginosa among the these macrophytes.

In this study, straw preservation effects of Arundo donax L. on its allelopathic activity to toxic and bloom-forming Microcystis aeruginosa were investigated. The aquatic extracts of fresh straw significantly inhibited the growth of M. aeruginosa. After 7 d of cultivation, the percentage inhibitions (PIs) of all treated groups were above 60% and the maximum almost reached 100%. However, when the straw was used after two-month preservation, its allelopathic activities decreased significantly with all PIs lower than 60%. To unclose the substance differences between fresh and long-time preserved straws, the contents of dissolved organic carbon (DOC) and ultraviolet-visible and fluorescence characteristics were analyzed. The results show that long-time preserved straw had lower DOC and UV254 values, weaker fluorescence intensities, and fluorescent substance loss. Further, the allelopathic fractions were isolated from the aquatic extracts of the straws by solvent extraction. The potential allelochemicals were analyzed by gas chromatography-mass spectrometry (GC-MS). The strong antialgal fractions of both fresh and long-time preserved straws were found to have various potential allelochemicals, including esters, ketones, alkaloids and phenolic acids. Their number was decreased from 21 to 9 after two-month preservation. The characteristics analysis of potential allelochemicals hinted that fresh A. donax might have more highly-effective allelochemicals than long-time preserved one.

To evaluate global warming potential (GWP) on livestock waste treatment and biomass production in rice field, methane (CH(4)) and nitrous oxide (N(2)O) fluxes from forage rice fields planted with 4 different cultivars (Oryza sativa L. cv. Hamasari, Leafstar, Kusahonami and Takanari) were measured. Each of the cultivars were subjected either to basal fertilization alone (control plots) (84 kg N ha(-1)), or to basal fertilization plus topdressing with liquid cattle waste or LCW (treatment plots) (567 kg N ha(-1)). Liquid cattle waste application to the rice field resulted in peak CH(4) fluxes ranging from 22.0 to 32.1 mg m(-1)h(-1) during flooded conditions and large N(2)O fluxes ranging from 526 to 8591 μg m(-1)h(-1) after midsummer drainage and final drainage. The GWP of the control plots was between 1358 and 3872 kg CO(2)eq ha(-1), while the treatment plots ranged between 4503 and 8426 kg CO(2)eq ha(-1) and more than 60% of the GWP was from the N(2)O emission in treatment plots. In both the control and treatment plots, the lowest GWPs per ton of above-ground biomass were found to be from the Leafstar cultivar, which had a higher aboveground biomass than other cultivars; 117 kg CO(2)eq t(-1) from the control and 257 kg CO(2)eq t(-1) from the treatment plots. Thus, both forage production and suitable disposal of the LCW may be able to be achieved concomitantly with lower levels of GWP by cultivation of Leafstar in our field.

To study the effects of allelochemicals of Arundo donax Linn. on the growth of Microcystis aeruginosa, the allelochemicals were extracted with three solvents (methanol, ethyl acetate and hexane), respectively. Based on the observation of algal morphology and the measurement of algal density and cell size, the results showed the allelochemicals extracted with all the three solvents had inhibition on M. aeruginosa. The appearance time of allelochemical inhibition increased as follows, allelochemicals extracted with methanolethyl acetatehexane. As treatment time extended, M. aeruginosa regrew at low doses of allelochemicals extracted with methanol. Their inhibitory effects at high doses were lower than those extracted with ethyl acetate and hexane. After 2 d and 4 d of treatment, the inhibition ratios of allelochemicals extracted with ethyl acetate and hexane reached almost 100%, respectively. The 50% effective concentrations (EC50, 6 d) of allelochemicals extracted with methanol, ethyl acetate and hexane were 0.17 g x L(-1), 0.05 g x L(-1) and 0.08 g x L(-1), respectively. The allelochemicals extracted with methanol caused cavities in cells, those with ethyl acetate caused cells into cavities, pieces and conglomeration, and those with hexane caused goffers on cells initially with conglomeration later. The allelochemicals extracted with all the three solvents decreased the cell size of M. aeruginosa, among which those extracted with ethyl acetate had the strongest action.

Four aquatic plants (Alternanthera philoxeroides, Typha latifolia, Sagittaria sagittifolia, Phragmites communis ) were cultured on P-enriched soil in a pot experiment to assess the phosphorus rhizosphere depletion effect and analysis the ratio of root to shoot, root morphology, phosphorus uptake efficiency and phosphorus use efficiency. An obvious variation in P concentration of the soil in the rhizophere and non- rhizophere was observed. Compared with the non-rhizosphere (available P: 167.53 microg x g(-1)), the available P in the rhizosphere soil of Alternanthera philoxeroides, Typha latifolia, Sagittaria sagittifolia and Phragmites communis was reduced to 80.17, 124.37, 155.38 and 161.75 microg x g(-1) respectively, with 81%, 42%, 18% and 16% reduction ratio of water-soluble phosphorus. More effective phosphorus depletion was achieved in Alternanthera philoxeroides by higher phosphorus uptake efficiency (1.32 mg x m(-1)), while rooting system was small and phosphorus use efficiency was low (0.34 g x mg(-1)). Phosphorus uptake efficiency of Typha latjfolia is much lower (0.52 mg x m(-1)) than that of Alternanthera philoxeroides, however, its strong rooting system enhanced soil exploration, with higher phosphorus use efficiency (0.64 g x mg(-1)) and the ratio of root to shoot (0.35). Alternantshera philoxeroides and Typha latfolia were more effective in phosphorus depletion of the rhizosphere soil than that in Sagittaria sagittifolia and Phragmites communis.

This paper presents an application of our newly developed adsorptive ozonation process using a high silica zeolite adsorbent (USY) for drinking water treatment. First, the adsorption of 2-methylisoborneol (2-MIB) on USY in a river water/pure water mixture was clarified by a batch-type adsorption experiment. The results showed that 2-MIB was adsorbed on USY; however, almost all of the adsorbed 2-MIB was desorbed over time. The desorption rate was increased with the ratio of river water to pure water, indicating that compounds dissolved in the river water, such as natural organic matter (NOM), prevent the adsorption of 2-MIB on USY. Second, the ability of the river water to consume ozone was confirmed in an experiment using a USY-packed column reactor. The ozone consumption was obviously increased by the presence of USY, indicating that USY-adsorbing compounds dissolved in the river water (probably small size NOM) consumed the ozone. However, the rapid ozone consumption was occurred by 6–8 s in the retention times when 3.14–4.38 mg L −1 of water dissolved ozone was fed, this rapid ozone consumption lasted no more than these times. This result revealed that the rapid consumption of ozone by the adsorptive compounds in our process could be avoided within a certain retention time (6–8 s; especially for the river water used in this study) when enough concentration of ozone (3.14 mg L −1 or more; same above) was supplied. We therefore performed a trial in which 2-MIB dissolved in river water was continuously decomposed using a USY-packed column with various ozone concentrations. In the process, the adsorptive compound dissolved in the river water adsorbed and reacted with ozone in the parts of the apparatus upstream of the column, while the adsorption and decomposition of 2-MIB took place in the parts of the apparatus downstream of the column. This resulted in a sufficient 2-MIB decomposition with minimizing bromate ion formation.

The adsorption properties of water-dissolved ozone on high silica zeolites were investigated. Adsorbed ozone was desorbed almost reversibly. The adsorption equilibrium relations were described by a linear expression written as q=betaC, where q is the amount adsorbed, C is the equilibrium concentration and beta is the equilibrium constant. Also, the beta values were strongly dependent on the SiO(2)/Al(2)O(3) ratio (mol/mol) and on the pore structure of the high silica zeolites. The larger the SiO(2)/Al(2)O(3) ratio, the larger the value of beta. ZSM-5 (SiO(2)/Al(2)O(3) ratio: 3000), which gave the highest adsorption capacity of water-dissolved ozone, was able to highly concentrate water-dissolved ozone on the adsorbent. The decomposition behavior of adsorbed ozone was also investigated. Ozone adsorbed on high silica zeolite was observed to be a little more stable than ozone existing in bulk water. The decomposition rate was independent of SiO(2)/Al(2)O(3) ratios in the range of 30-3000 or a solution pH in the range of 4-6.

We developed a novel ozonation process for water treatment using high silica zeolites as an adsorptive concentrator of water-dissolved ozone and organic pollutants, resulting in a significant increase in reaction rate. In experiments involving trichloroethene (TCE) decomposition using a tubular flow reactor, TCE decomposition was much greater in the presence of ZSM-5 (SiO(2)/Al(2)O(3) ratio=3000) than in its absence, possibly due to the high concentrations of ozone and TCE inside the adsorbent. The TCE conversion obtained in our experiments was found to reach its theoretically maximum limit.

Concern about the overall management of lakes has been growing, and a lake ecological model provides the guidelines necessary for such management. In this study, an ecological model describing the ecosystem of the Keszthely Basin, Lake Balaton, Hungary, one of the typical shallow and eutrophic lakes, was proposed. This model includes three types of zooplankton and two types of fish as well as two types of algae and nutrients. Parameters concerning the algae and fish were estimated based on observations in the basin between 1991 and 1995. The other parameters and the structure of the model were determined by our previous study. The parameters of the model were calibrated with the Monte Carlo technique, and its predictability was confirmed. The effects on the basin's ecosystem of three restorative manipulations, namely a biomanipulation, reduction of loading phosphorus, and dredging the sediment, were assessed by simulation studies using the proposed model. The simulation results indicated that a biomanipulation that removed 90% of the bream should suppress the growth of algae temporarily through bottom–up regulation; however, this effect seemed to not be perpetuated in this basin. The reduction of loading phosphorus seemed to be the most effective means to suppress algal growth, while dredging of sediment seemed to be the most desirable restoration method from the standpoint of the overall management of the lake, because it was expected to accelerate the growth of fish population as well as to suppress algal growth. Furthermore, the algal growth suppresion mechanism of the dredging was disccused on the basis of the model calculations.