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41.
The carcinogenic amino-alpha-carbolines, 2-amino-9H-pyrido[2,3-b]indole and AalphaC, have been measured in airborne particles, rain water, soil and cigarette-smoke-polluted indoor air by high-performance liquid chromatography. These carcinogens were found in all kinds of environmental samples examined, although MeAalphaC was not detected in soil. Considering the present results, together with the previous findings that these carcinogens were present in foodstuffs, cigarette smoke and diesel-exhaust particles, amino-alpha-carbolines are likely to be ubiquitous environmental pollutants. Our data also support the hypothesis that amino-alpha-carbolines are formed through combustion of various materials such as food, grass and petroleum.  相似文献   
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Japan Atomic Energy Research Institute has developed an emergency response system WSPEEDI to forecast long-range atmospheric dispersions of radionuclides discharged into the atmosphere. The latest version of WSPEEDI consists of an atmospheric dynamic model MM5 for calculating meteorological fields and a particle random-walk model for atmospheric dispersion. The performance of WSPEEDI was evaluated by data obtained from a field tracer experiment over Europe (ETEX) in this paper. The model validation was done with respect to the following points: (1) the dependence of model accuracy on the temporal and spatial resolutions of the meteorological fields and (2) the superiority of an atmospheric dynamic model over a mass-consistent wind model. Regarding (1), it was shown that the calculation accuracy of the new version with high temporal resolution was improved, especially at the edge of the plume. Moreover, although the increase in horizontal spatial resolution of the old version had no substantial effect on the model performance, increase in horizontal resolution of the new version contributed to the significant improvement of the calculation accuracy. These results showed that the dynamically calculated meteorological field with the spatial resolution of the meso-βγ scale greatly improved calculation accuracy.  相似文献   
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From the global perspective, the issue of waste management is becoming increasingly important. Given the increasing amount and diversifying content of waste, countries should seek out sustainable waste management options, which protect both local and global environments. The Global Environment Facility (GEF), a public financial institution, has supported sustainable waste management in developing countries in achieving global environmental benefits. The GEF’s support for sustainable waste management, from its pilot phase to the end of the fifth replenishment period, has amounted to 118 projects across the globe. Harmful chemicals, such as polychlorinated biphenyls (PCBs), and “waste to energy” initiatives have been the main focuses of the GEF’s support. The GEF’s investment in sustainable waste management has increased in recent years, partly due to the fact that countries are required to manage Persistent Organic Pollutant (POP) wastes in an environmentally safe manner in compliance with the Stockholm Convention on POPs. The GEF is poised to enhance its support for sustainable waste management in the future by mobilizing other financing, integrating multiple focal areas, expanding viewpoints to sustainable cities, and reinforcing its results-based management.  相似文献   
46.
Norovirus GII.3, GII.4, and GII.17 were detected using pyrosequencing in sewage and oysters in January and February 2015, in Japan. The strains in sewage and oyster samples were genetically identical or similar, predominant strains belonging to GII.17 Kawasaki 2014 lineage. This is the first report of GII.17 Kawasaki 2014 in oysters.  相似文献   
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Chemical recycling of waste poly(ethylene terephthalate) (PET) using phosphoric acid–modified silica gel as a solid catalyst is reported. Advantageously, microwave irradiation was used to progress the depolymerization of PET. In this study, depolymerization of PET with a small amount of water is suggested as a suitable method. The depolymerized product, terephthalic acid was obtained and assigned by 1H NMR and FT-IR spectroscopy. Finally, over 90 % conversion to terephthalic acid was achieved when waste plastic bottles were treated with the method. This results confirm the importance of the microwave power technique as a promising recycling method for plastic bottles made from PET, resulting in monomer recovery in addition to substantial energy saving.  相似文献   
48.
For a prospective solution of effective recycling of gypsum board wastes, the present study was conducted to evaluate applicability of reclaimed gypsum as stabilizing agent for improvement of soft clayey ground. A series of unconfined compression tests and needle penetration tests were conducted to understand the fundamental properties of reclaimed gypsum and gypsum treated soils and the durability in water. An important finding was strength decrease in relation to mixing time of gypsum and soil. This may attribute to excessive mixing that caused breakage of the promptly hardened gypsum treated clay. In addition, from sounding and laboratory tests on the stabilized ground by shallow mixing method with different execution conditions, it was found that the strength of stabilized ground appeared in an early stage and that the hardening effect of cement that was used in combination with gypsum continued in a longer period. Regarding an environmental aspect, a specific amount of cement could have restrained leaching fluorine satisfactorily under the standard level in the field by adopting suitable mixing proportions based on the laboratory mixing test results. For practical application, the mixing procedure was a major factor of strength growth when hemihydrate gypsum was used to stabilize soft clayey ground.  相似文献   
49.
Non-methane hydrocarbons (NMHCs) are known to have an important role on air quality due to their high reactivity. NMHC analysis has been performed on 148 ambient air samples collected at five different sites in the Kanto area (Tokyo metropolitan area and surrounding six prefectures) of Japan in summer and winter of 2008, and fifty NMHCs have been determined and quantified. A field measurement campaign has been conducted at one of the busiest intersections in Tokyo metropolitan area in winter of 2008. NMHC emissions are evaluated through comparison of distributions of individual NMHCs emitted from motor vehicles, which are estimated from the measurements, with those determined from the current emissions inventory. The comparison revealed that the measured distributions of acetylene, ethylene and toluene showed a good agreement with those estimated from the emissions inventory (the values estimated from the measurements are a factor of 1.5, 0.56 and 2.3 larger than the emissions inventory in median, respectively), however, propane and isobutane are found to be significantly underestimated in the emissions inventory (the measured values were a factor of 18 and 5.1 larger than the emissions inventory, respectively). The significant underestimate of propane can be explained by that the current emissions inventory does not consider emissions from liquefied propane gas (LPG) fueled vehicles. However, for isobutane, reasons for the underestimate are still unclear. Another field measurement has been conducted in summer of 2008, where the air samples have been collected at three different sites on the ground and by a helicopter as well. Remarkable high concentrations of 1-butene and cis- and trans-2-butenes have been sporadically observed in the samples collected at Urayasu in the coastal area of Tokyo bay. Calculated propylene equivalent (PE) concentrations of butenes revealed that those have a significantly important role in ozone formation when the air plume is affected by emissions from their emission sources. The PE concentrations of butenes varied from 0.1 to 39 ppbC, and accounted for 1.5–75% of total PE concentrations at Urayasu. Most of the continuous air quality monitoring stations does not record concentrations of individual hydrocarbons, therefore, the importance of reactive and low concentration hydrocarbon such as butenes might be overlooked in the current emissions inventory and/or air quality model. In this paper, the reliability of NMHC emissions is evaluated based on the field measurements. Their possible impacts on air quality in the Kanto area are discussed as well, based on the calculated propylene equivalent concentrations.  相似文献   
50.
To analyze the effect of polychlorinated biphenyl (PCB) 118 on fish bone metabolism, we examined osteoclastic and osteoblastic activities, as well as plasma calcium levels, in the scales of PCB (118)-injected goldfish. In addition, effect of PCB (118) on osteoclasts and osteoblasts was investigated in vitro. Immature goldfish, in which the endogenous effects of sex steroids are negligible, were used. PCB (118) was solubilized in dimethyl sulfoxide at a concentration of 10 ppm. At 1 and 2 days after PCB (118) injection (100 ng/g body weight), both osteoclastic and osteoblastic activities, and plasma calcium levels were measured. In an in vitro study, then, both osteoclastic and osteoblastic activities as well as each marker mRNA expression were examined. At 2 days, scale osteoclastic activity in PCB (118)-injected goldfish increased significantly, while osteoblastic activity did not change significantly. Corresponding to osteoclastic activity, plasma calcium levels increased significantly at 2 days after PCB (118) administration. Osteoclastic activation also occurred in the marker enzyme activities and mRNA expressions in vitro. Thus, we conclude that PCB (118) disrupts bone metabolism in goldfish both in vivo and in vitro experiments.  相似文献   
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