An Integrated Assessment by Models for Energy Systems Analysis and Life-Cycle Assessment with a Case Study of Advanced Fossil-Fired Power Plants in China

We developed an integrated assessment (IA) using models for energy systems analysis and life-cycle assessment (LCA). Based on this assessment framework, we developed cost-benefit analysis (CBA) case studies for a hypothetical project designed to introduce advanced fossil-fired power generation technologies in China. Our MARKAL model for Japan confirmed that radical reductions (i.e., 80 % by 2050) of carbon dioxide (CO₂) could be attained from energy systems alone and that credit for emission allowances was required. We evaluated life-cycle costs and emissions of carbon dioxide, sulfur oxide, and nitrogen oxide gases for the energy technologies using an LCA model. Further, we applied a power generation planning model for six Chinese grids to provide a power mix structure, potentially producing credit by installing fossil-fired power generation technology and by using baseline grid emission factors with an average cost of electricity. Finally, by using dynamic emission reductions and additional costs from the two models, we conducted case studies of CBA for a hypothetical project to install the technologies in China. This was accomplished by evaluating emission reductions in monetary terms and by applying a life-cycle impact assessment model. A unique feature of our IA is its dynamic (time-varying) assessment of costs and benefits.     

Survey on readability of online information for upgrading understandability of biomass energy technology

Waste management contributes to renewable energy such as biodiesel production from processes of various types of biomass including vegetable oils, animal fats, and waste of edible oil. Successful waste management effort is influenced by people concern about benefit of waste management including for renewable energy from biomass. It involves their understanding initiated by literacy on biomass energy. To help increase literacy on waste recycle and biomass energy technology, we study readability of online information regarding biomass energy in Indonesian language (Bahasa Indonesia). Indonesia is considered as one of biomass-rich country with a little utilization for energy. The readability is studied by combining two approaches: measurement by readability standard and survey on readability confirming measurement by the standard. This study focuses on the confirmation survey readability standard measured on biomass online information in Indonesian language. In the survey, 19 online text materials were read by respondents and they were asked to give their impression whether the texts are easy or difficult to understand. From this study, what factors influence understandability of text information are shown. The results could be a guidance for preparing text information to raise people concern on waste recycle and renewable energy in general.     

Conditions controlling the onset of breeding migration of the Japanese mountain stream frog, <Emphasis Type="Italic">Rana sakuraii</Emphasis>

I studied the conditions controlling the timing of breeding migration of the Japanese mountain stream frog Rana sakuraii, an explosive breeder, over 9 years (1992, 1993 and 1999–2005). I analysed two factors: the daily cumulative temperature (DCT) during hibernation and the triggering temperature on the day of migration onset. Frogs hibernated in shallow running water in streams in December. A total of 53,155 breeding migrating adults were captured by traps. Every year, breeding migration was induced by a rise in daily maximum water temperature to about 5°C. However, its date was limited to 1 February at the earliest, and the onset needed a DCT (from 20 January, using 3°C as the threshold for daily effective temperature) of at least about 15°C. Earlier (e.g. in mid- or late January), even if the maximum temperature rose to 5–8°C, migration did not begin. Moreover, even in early February, if the maximum temperature rose to 5°C, if it had been too cold in January and the DCT was low, migration would not begin until mid- or late February. Thus, the earliest date of readiness for migration varied from 1 February to mid-February, depending on the winter DCT. Logistic regression analyses showed that both factors, the DCT and the daily temperature, were significant. I propose that in temperate-zone amphibian explosive breeders, both the passing of an essential number of days and an essential DCT during hibernation are prerequisites for the onset of breeding migration before the daily temperature rises to the threshold.     

Preparation of Galactomannan-Based Materials Compatibilized with Ionic Liquids

This paper reports the preparation of galactomannan/ionic liquid composite materials from the corresponding ion gels. Three kinds of galactomannans, that is, fenugreek gum (FG), guar gum (GG), and locust bean gum (LBG) and an ionic liquid of 1-butyl-3-methylimidazolium chloride (BMIMCl) were used. When the galactomannan/BMIMCl gels were immersed in ethanol, followed by dryness under reduced pressure, the galactomannan/BMIMCl composite materials were obtained. The crystalline structures of galactomannans in the materials were evaluated by the powder X-ray diffraction measurement. The mechanical property of the FG/BMIMCl composite material under compressive mode was superior compared with the GG and LBG/BMIMCl composite materials. Then, FG films compatibilized with polymeric ionic liquids (PILs) were also prepared by in situ radical polymerization of polymerizable ionic liquids, 1-(3-acryloyloxypropyl)-3-vinylimidazolium bromide and 1-methyl-3-vinylbenzylimidazolium chloride by AIBN in mixtures of FG with BMIMCl. The mechanical properties of the resulting films were affected by the FG/PIL ratios as well as the unit ratios in PILs.     

Degradation activity of Clostridium species DC-1 in the cis-1,2-dichloroethylene contaminated site in the presence of indigenous microorganisms and Escherichia coli

We showed the cis-1,2-dichloroethylene (cis-1,2-DCE) dechlorination ability of Clostridium species DC-1 in association with other bacteria. Result of denaturing gradient gel electrophoresis showed the dominant band pattern of DC-1 during the degradation time of cis-1,2-DCE and dominance of some other Clostridium species. Experiment with addition of Escherichia coli (E. coli) showed that dechlorinating activity of DC-1 was not inhibited by the presence of E. coli. Pour plate experiment with DC-1 and E. coli revealed that the dominance of Clostridium species caused the decrease of E. coli growth in a bioremediation state. This result suggested the possibility of Clostridium species DC-1 as a degrader of cis-1,2-DCE, in a cis-1,2-DCE contaminated site where an indigenous microbial community is present. Experiment conducting with E. coli suggested that the strain in the contaminated site did not inhibit the degradation of cis-1,2-DCE and during the degradation period, rather some other Clostridium species became dominant and the growth of E. coli would be decreased. This finding could be a very positive approach for implementing the dechlorinating bacteria at aliphatic chlorinated component contaminated sites.     

Finite element analysis of knee injury risks in car-to-pedestrian impacts

In vehicle-pedestrian collisions, lower extremities of pedestrians are frequently injured by vehicle front structures. In this study, a finite element (FE) model of THUMS (total human model for safety) was modified in order to assess injuries to a pedestrian lower extremity. Dynamic impact responses of the knee joint of the FE model were validated on the basis of data from the literature. Since in real-world accidents, the vehicle bumper can impact the lower extremities in various situations, the relations between lower extremity injury risk and impact conditions, such as between impact location, angle, and impactor stiffness, were analyzed. The FE simulation demonstrated that the motion of the lower extremity may be classified into a contact effect of the impactor and an inertia effect from a thigh or leg. In the contact phase, the stress of the bone is high in the area contacted by the impactor, which can cause fracture. Thus, in this phase the impactor stiffness affects the fracture risk of bone. In the inertia phase, the behavior of the lower extremity depends on the impact locations and angles, and the knee ligament forces become high according to the lower extremity behavior. The force of the collateral ligament is high compared with other knee ligaments, due to knee valgus motions in vehicle-pedestrian collisions.     

Thermal cracking of oils from waste plastics

Thermal cracking of decomposed waste plastic oil produces a good yield of olefins. The solvent extraction of such waste plastic oil seems to be efficient for increasing gas yields and recycling monomers. To assess the potential of monomer recovery from municipal waste plastics, the oils were cracked using a laboratory-scale quartz-tube reactor. The waste plastic oils were provided by two commercial plants of the Sapporo Plastic Recycle Co. and the Dohoh Recycle Center Co. in Japan. A model waste plastic oil made in a laboratory was also examined. Yields of ethene, propene, and other products were measured at different temperatures. Two-step pyrolysis reduces coking compared with the direct thermal degradation of plastics. The raffinates from waste plastic oils extracted by sulfolane were also cracked. The primary products were almost the same as those from nontreated oils. The maximum total gas yield was 78wt%–85wt% at 750°C, an increase of about 20wt% compared with that of nonextracted oil. Solvent extraction removes stable aromatic hydrocarbons such as styrene, which is more coked than cracked.     

Analysis of biomagnification of persistent organic pollutants in the aquatic food web of the Mekong Delta, South Vietnam using stable carbon and nitrogen isotopes

The present study elucidated the biomagnification profiles of persistent organic pollutants (POPs) through a tropical aquatic food web of Vietnam based on trophic characterization using stable nitrogen analysis. Various biological samples collected from the main stream of the Mekong Delta were provided for the analysis for both POPs, and stable nitrogen and carbon isotope ratios. Of the POPs analyzed, dichlorodiphenyltrichloroethane and its metabolites (DDTs) were the predominant contaminants with concentrations ranging from 0.058 to 12 ng/g wet weight, followed by polychlorinated biphenyls (PCBs) at 0.017-8.9 ng/g, chlordane compounds (CHLs) at 0.0043-0.76 ng/g, tris-4-chlorophenyl methane (TCPMe) at N.D.-0.26 ng/g, hexachlorocyclohexane isomers (HCHs) at N.D.-0.20 ng/g and hexachlorobenzene (HCB) at 0.0021-0.096 ng/g. Significant positive increases of concentrations in DDTs, CHLs, and TCPMe against the stable nitrogen ratio (delta(15)N) were detected, while, concentrations of HCHs and HCB showed no significant increase. The slopes of the regression equations between the log-transformed concentrations of these POPs and delta(15)N were used as indices of biomagnification. The slopes of the POPs for which positive biomagnification was detected ranged from 0.149 to 0.177 on a wet weight basis. The slopes of DDTs and CHLs were less than those reported for a marine food web of the Arctic Ocean, indicating that less biomagnification had occurred in the tropical food web. Of the isomers of CHLs, unlike the studies of the Arctic Ocean, oxychlordane did not undergo significant biomagnification through the food web of the Mekong Delta. This difference is considered to be due to a lack of marine mammals, which might metabolize cis- and trans-chlordane to oxychlordane, in the Mekong Delta ecosystem. The biomagnification profile of TCPMe is reported for the first time in the present study.