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91.
Objectives: An airbag system for motorcycle applications was developed and marketed in 2006 followed by many research projects on the system. In the airbag system, the bag should be supported during the kinetic energy–absorbing period of a rider in a collision. The previously developed system employed a configuration in which motorcycle structures support the airbag, such as a gauge unit and/or a steering structure. The supporting structure functions to receive the reaction force to hold the airbag during a crash to properly absorb the rider's kinetic energy. However, the previous system requires a larger area for this reaction structure and is applicable only to the motorcycles that can provide that area. To overcome this limitation, we propose an airbag system employing another concept. In this concept, the airbag does not use its vehicle structures as a reaction structure but uses the structures of an opposing vehicle, such as doors and/or pillars of an opposing vehicle. In this project, we aim to verify the effectiveness of the proposed system when installed in a motorcycle that cannot provide a larger area for the reaction structure.

Methods: In the system with this concept, it is assumed that the occupant protection performance is largely affected depending on impact configurations. Accordingly, full-scale motorcycle-to-car crash tests using 125 cm3 scooter-type models with and without the proposed system were conducted in various impact configurations. The 7 impact configurations specified in ISO 13232 were selected as the test configurations. Injury variables and injury indices of head, neck, chest, and abdomen were evaluated with the motorcyclist dummy.

Results: Injury variables and indices obtained from the crash tests with the airbag were compared to those of the baseline tests. In 2 impact configurations, the airbags were supported by the side structures of the opposing vehicle and performed to reduce the injury variable of head and/or chest compared to that of the baseline test.

Conclusion: Through the crash tests, beneficial protection effects of the airbag system were confirmed in particular impact configurations. No significant risk for the occupant due to the airbag was observed in the conducted crash tests. It was concluded that the proposed airbag system has feasibility to reduce rider injury in a collision of a motorcycle without sufficient reaction structure.  相似文献   
92.
Journal of Material Cycles and Waste Management - Low-cost and effective activated carbon for copper ion adsorption was prepared from walnut shell by CO2 activation in a fluidized bed. The effects...  相似文献   
93.
Blood clinical-chemical parameters (BCCPs) are used to investigate physiological consequences attributed to exposure to anthropogenic stressors, such as exposure to Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and Dechlorane Plus (DP), which are flame retardants (FRs), on avian health. Japanese quail (Coturnix japonica) were used as a model species to investigate individual and mixture effects of both FRs by injecting different concentrations (5, 50, or 500 ng/µL) of either of these compounds as well as a 1:1 mixture of both into fertilized eggs. To estimate post-hatching effects, 18 BCCPs were evaluated from 101 chicks at day 14. Albumin levels were found to be significantly elevated in the groups exposed to high doses of TDCIPP alone as well as a mixture of TDCIPP and DP. However, during the course of the study, the initial corn-based feed had to be substituted by a fishmeal-based feed. The 8 days consuming the new feed played a significant role on 12 of 18 BCCPs measured. Consequently, it is recommended that dietary habits need to be considered when investigating the physiological impact of contaminants using BCCPs as biomarkers in growing nestlings both in controlled in vivo and field experiments.  相似文献   
94.
Influence of irrigation methods and use of an adjuvant on the persistence of the carbaryl (1-naphthyl N-methylcarbamate) on pakchoi [Brassica rapa L. subsp. chinensis (Rupr.) Olsson] was studied using a commercial enzyme linked immunosorbent assay kit. After applying carbaryl at a.i. 10.6 g L(-1) with or without an adjuvant (Latron B-1956) to leaves, plants were provided water daily by either overhead or basal application. Pesticide residue on leaf tissues was examined immediately after pesticide application and on 2, 4, 6, and 8 d after pesticide application. Use of the adjuvant did not affect the initial deposit of the pesticide, however pesticide persistence was improved with the adjuvant regardless of irrigation. Overhead irrigation contributed to rapid loss of the pesticide by washing carbaryl from the leaf surface. The longest half-life of carbaryl (6.5 d) was detected on plants receiving basal irrigation plus the adjuvant while the shortest half-life (2 d) was observed when plants were treated with overhead irrigation and no adjuvant.  相似文献   
95.
The distribution of trace elements throughout mining areas is an important issue because abandoned tailings could be a major source of environmental pollution. In order to analyze the spatial variation of trace elements in a zone where mining activities took place and to identify pollution sources in the study area, a three-step study was carried out at a regional, at a local, and a detailed scale. In addition, a conceptual model of trace elements dispersion was established and confirmed by a geographic information system. The results obtained allowed to establish points affected by primary, secondary, and tertiary contamination, according to their proximity to contamination sources and as a function of attenuation processes which could take place in the studied area.  相似文献   
96.
97.
Aquacultured fish gilthead seabream (Sparusaurata), previously exposed to low levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) trough the diet for a 13 months period, were fed on a clean feed for another 22 months. Gilthead seabream is a protandrous hermaphrodite species and this “decontamination” period coincided with the stages of sex differentiation, maturity and reproduction of the fish. PCDD/F levels in the fish tissues (i.e. muscle, liver, perivisceral fat and gonads), expressed in pg WHO-TEQ g−1 fresh weight, showed a general decreasing trend during the “decontamination” period. However, this general trend varied among tissues and was also dependent on sex and lipid contents. Toxicological effects affecting fish behaviour and hepatic marker responses were also evaluated. The results pointed out that exposure to PCDD/Fs did not have an impact on fish development and reproduction, since the proportion of sexes found after the sex reversal process was within the normal range described for this species. In addition, long-term exposure to low PCDD/F levels did not significantly affect the response of most of the biochemical markers considered. On the contrary, some of them (e.g. EROD activity) showed variations in their responses during the sex differentiation process and onwards. Finally, the hepatic AhR mRNA levels increased during dioxin exposure but they returned to values typical for non-exposed fish after the “decontamination” period.  相似文献   
98.
Since 2002, the chemical/petrochemical industrial zone of Tarragona County (Catalonia, Spain) is being annually monitored. As part of the environmental surveillance program, in this study the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polycyclic aromatic hydrocarbons (PAHs), and metals (As, Cd, Cr, Hg, Mn, Pb and V) were determined in soil and vegetation samples collected in 4 areas of Tarragona County (chemical, petrochemical, urban/residential, and unpolluted). Moreover, the airborne concentrations of the same micropollutants were determined in each area. In soil samples, significant higher levels of PCNs and higher concentrations of PCDD/Fs and PAHs were found in the urban zone. PCDD/F levels in vegetation samples significantly decreased from 2002. The concentrations of Cr in soil samples, as well as V levels in vegetation samples collected in the vicinity of an oil refinery were significantly higher than those found in the unpolluted zones. A significant and progressive increase in V concentrations was also noted. The current results clearly indicate that the petrochemical industry is still being an important focus of inorganic pollution for the surrounding environment. In air, the higher amount of the 7 carcinogenic PAHs suggests a relatively greater impact on the petrochemical and urban areas. The temporal trend of the global pollution was also studied an Integral Risk Index was applied.  相似文献   
99.
Modelling-based studies to assess the extent and magnitude of ozone (O3) risk to agriculture in Asia suggest that yield losses of 5–20% for important crops may be common in areas experiencing elevated O3 concentrations. These assessments have relied on European and North American dose–response relationships and hence assumed an equivalent Asian crop response to O3 for local cultivars, pollutant conditions and climate. To test this assumption we collated comparable dose–response data derived from fumigation, filtration and EDU experiments conducted in Asia on wheat, rice and leguminous crop species. These data are pooled and compared with equivalent North American dose–response relationships. The Asian data show that at ambient O3 concentrations found at the study sites (which vary between ~35–75 ppb 4–8 h growing season mean), yield losses for wheat, rice and legumes range between 5–48, 3–47 and 10–65%, respectively. The results indicate that Asian grown wheat and rice cultivars are more sensitive to O3 than the North American dose–response relationships would suggest. For legumes the scatter in the data makes it difficult to reach any equivalent conclusion in relative sensitivities. As such, existing modelling-based risk assessments may have substantially underestimated the scale of the problem in Asia through use of North American derived dose–response relationships.  相似文献   
100.
Increasing human activity continues to threaten peatlands, and as the area of natural mires declines, our obligation is to restore their ecosystem functions. Several restoration strategies have been developed for restoration of extracted peatlands, including “The moss layer transfer method”, which was initiated on the Tässi extracted peatland in central Estonia in May 2012. Three-year study shows that despite the fluctuating water table, rainfall events can compensate for the insufficient moisture for mosses. Total plant cover on the restoration area attained 70 %, of which ~60 % is comprised of target species—Sphagnum mosses. From restoration treatments, spreading of plant fragments had a significant positive effect on the cover of bryophyte and vascular plants. Higher water table combined with higher plant fragments spreading density and stripping of oxidised peat layer affected positively the cover of targeted Sphagnum species. The species composition in the restoration area became similar to that in the donor site in a natural bog. Based on results, it was concluded that the method approved for restoration in North America gives good results also in the restoration of extracted peatland towards re-establishment of bog vegetation under northern European conditions.  相似文献   
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