Inactivation effect of pressurized carbon dioxide on bacteriophage Qβ and ΦX174 as a novel disinfectant for water treatment

The inactivation effects of pressurized CO2 against bacteriophage Qβ and ΦX174 were investigated under the pressure of 0.3–0.9 MPa, initial concentration of 107–109PFU/mL, and temperature of17.8°C–27.2°C. The optimum conditions were found to be 0.7 MPa and an exposure time of 25 min. Under identical treatment conditions, a greater than 3.3-log reduction in bacteriophage Qβ was achieved by CO2, while a nearly 3.0 log reduction was observed for phage ΦX174. The viricidal effects of N2O(an inactivation gas with similar characteristics to CO2), normal acid(HCl), and CO2 treatment with phosphate buffered saline affirmed the chemical nature of CO2 treatment. The pumping cycle, depressurization rate, and release of intracellular substances caused by CO2 were its viricidal mechanisms. The results indicate that CO2 has the potential for use as a disinfectant without forming disinfection by-products.     

Analyzing flood risk and related impacts to urban communities in central Vietnam

This study aims at understanding flood risks and their impact on a community, in order to enhance communities’ resilience and adaptive capacity to these threats. It also investigates the possibility of looking at and handling risk from a resilience point of view. Therefore, while a conventional risk management process is employed in this study, social, physical, economic, and institutional dimensions of resilience are also included in order to grasp the extent of risks and the ways in which communities face, cope with, and recover from flooding. Findings showed that there was no significant difference in the perception of flood risk among household heads educated up to secondary school level, suggesting that they believe floods are purely natural events. Those with a higher level of education (high school and above) (82.7 % of respondents) were aware that flood disasters are the result of hazard and vulnerability combined. In addition, social dynamics were apparently strengthened by such disasters, which resulted in cohesion and mutual help following floods in some wards. Also, households with more sources of income and more savings appear to recover faster than others after a flooding event. With regard to governance and networks, greater efforts have to be made by local institutions to ensure basic functioning during and after disaster events and to invest more into risk reduction activities. However, further studies need to be conducted to clarify the understanding of the impact flood disasters have on the environment and community lives and livelihoods in general, as traditional coping strategies, although still practical, no longer suffice in the face of changes in climate and environment.     

Post furnace formation of PCDDs and PCDFs in MSWI: Observations in an incinerator installed with quench reactor

Reduction of dioxin emission by a quench reactor with lime spray was investigated in relation to post furnace formation pathways. Results showed that the quench reactor performed to supress post furnace reaction of precursor molecules to form selected congeners of PCDD and PCDF.     

Modeling the influence of biogenic volatile organic compound emissions on ozone concentration during summer season in the Kinki region of Japan

Tropospheric ozone adversely affects human health and vegetation, and biogenic volatile organic compound (BVOC) emission has potential to influence ozone concentration in summer season. In this research, the standard emissions of isoprene and monoterpene from the vegetation of the Kinki region of Japan, estimated from growth chamber experiments, were converted into hourly emissions for July 2002 using the temperature and light intensity data obtained from results of MM5 meteorological model. To investigate the effect of BVOC emissions on ozone production, two ozone simulations for one-month period of July 2002 were carried out. In one simulation, hourly BVOC emissions were included (BIO), while in the other one, BVOC emissions were not considered (NOBIO). The quantitative analyses of the ozone results clearly indicate that the use of spatio-temporally varying BVOC emission improves the prediction of ozone concentration. The hourly differences of monthly-averaged ozone concentrations between BIO and NOBIO had the maximum value of 6 ppb at 1400 JST. The explicit difference appeared in urban area, though the place where the maximum difference occurred changed with time. Overall, BVOC emissions from the forest vegetation strongly affected the ozone generation in the urban area.     

Chlordane residues in krill,fish and Weddell seal from the Antarctic

Chlordane compounds (CHLs) were quantitated in krill (Euphausia superba), benthic fish (Trematomus bernacchii) and Weddell seal (Leptonychotes weddelli) collected around the Japanese Antarctic Research Station (Syowa Station: 69°00'S, 39°35'E). The concentrations of ZCHL (cis‐, trans‐chlordane+ cis‐, fraws‐nonachlor + oxych‐lordane) in krill was much lower than that of benthic fish. The ratio of SCHL to sum of SCHL, SDDT and PCBs decreased with the trophic levels. These results indicate that CHLs appear to be easily degraded in higher organisms.     

氯代芳香族化合物电化学还原特性的测定及QSPR研究

运用定量结构-性质相关技术研究了萘、联苯、苯、苯酚等4类共87种氯代芳香族化合物的电化学还原特性与分子结构间的定量关系结果表明,化合物的还原电极电位除了与最低未占据分子轨道能EL_UMO有显著相关性以外,还与分子中氯原子个数n_CI存在一定相关性,从而揭示了氯代芳香族化合物电化学还原的内在规律,为有害污染物高级还原处理技术的开发与工艺设计提供了有价值的基础数据.     

Kinematics of the unrestrained vehicle occupants in side-impact crashes

A test series involving direct right-side impact of a moving wall on unsupported, unrestrained cadavers with no arms was undertaken to better understand human kinematics and injury mechanisms during side impact at realistic speeds. The tests conducted provided a unique opportunity for a detailed analysis of the kinematics resulting from side impact. Specifically, this study evaluated the 3-dimensional (3D) kinematics of 3 unrestrained male cadavers subjected to lateral impact by a multi-element load wall carried by a pneumatically propelled rail-mounted sled reproducing a conceptual side crash impact. Three translations and 3 rotations characterize the movement of a solid body in the space, the 6 degrees of freedom (6DoF) kinematics of 15 bone segments were obtained from the 3D marker motions and computed tomography (CT)-defined relationships between the maker array mounts and the bones. The moving wall initially made contact with the lateral aspect of the pelvis, which initiated lateral motion of the spinal segments beginning with the pelvis and moving sequentially up through the lumbar spine to the thorax. Analyzing the 6DoF motions kinematics of the ribs and sternum followed right shoulder contact with the wall. Overall thoracic motion was assessed by combining the thoracic bone segments as a single rigid body. The kinematic data presented in this research provides quantified subject responses and boundary condition interactions that are currently unavailable for lateral impact.     

PM<Subscript>2.5</Subscript>-related health impacts of utilizing ammonia-hydrogen energy in Kanto Region,Japan

Ammonia has emerged as a promising hydrogen carrier with applications as an energy source in recent years. However, in addition to being toxic, gaseous ammonia is a precursor of secondary inorganic aerosols. The concentration of ambient fine particulate matter (PM_2.5) is intrinsically connected to public health. In this study, PM_2.5-related health impacts of utilizing ammonia-hydrogen energy in Kanto Region, Japan, were investigated. It was assumed that 20% of the electricity consumption in Kanto Region, the most populated area in Japan, was supplied by ammonia-hydrogen energy. The PM_2.5 resulted from incomplete ammonia decomposition was simulated by a chemical transport model: ADMER-PRO (modified version). Based on the incremental PM_2.5 concentration, health impacts on the elderly (individuals over 65 years old) were quantitatively evaluated. The ammonia emission in this scenario increased PM_2.5 by 11.7% (0.16 μg·m^–3·y^–1) in winter and 3.5% (0.08 μg ·m^–3·y^–1) in summer, resulting in 351 premature deaths per year. This study suggests that costeffective emissions control or treatment and appropriate land planning should be considered to reduce the associated health impacts of this type of energy generation. In addition, further in-depth research, including cost-benefit analysis and security standards, is needed.

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