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A continuous investigation of aerosol pollutants in Cape Hedo, Japan was conducted from October 2005 to August 2006 by Aerodyne aerosol mass spectrometer (AMS). This article focused on the analysis of long-range transport of organic aerosol from continental origin to the remote island. Based on the transport distance and air mass origin, four main air mass origins were considered, including North China, South China, Japan and Korea. Although the mass concentration and air mass origin were quite different during study period, the mass spectrum and size distribution of organic matter and oxidized organics were similar, which showed uni-modal distribution with modal diameter of around 500 nm. The loss rate of organics was (5.15 ± 0.55) × 10-6 s-1 obtained by plotting the concentration against the transport time. Conversion rate of SO2 to sulfate and oxidation rate of organics were (1.07 ± 0.15) × 10-5 and (1.09 ± 0.52) × 10-6s-1, respectively. 相似文献
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Shiro Tsuyuzaki 《Environmental management》1995,19(5):773-777
To determine the status of the vegetation of ski slopes in northeastern-central Honshu, Japan, 94 plots (2×2 m) were set up
on five ski areas (101–520 m elevation) which were established between 1945 and 1985 by forest clear-cutting, land modification,
and seeding. Six vegetation types were recognized: five grasslands dominated byDigitaria adscendens, Miscanthus sinensis, Zoysia japonica, Festuca rubra, andPteridium aquilinum var.latiusculum, respectively, and bare areas of very low to no vegetation cover. Of the dominant species,F. rubra is the only introduced species; it does not, however, appear to persist. After the introduced grassland declinesM. sinensis or annual grasslands develop. Native plants, especially woody species, can establish inM. sinensis grassland but do not establish in the other grasslands. It is concluded that the introduction of exotic species is inappropriate
to maintain ski slope vegetation, and the development ofM. sinensis grassland is desirable to promote natural revegetation. 相似文献
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Manabe S Kurihara N Wada O Izumikawa S Asakuno K Morita M 《Environmental pollution (Barking, Essex : 1987)》1993,80(3):281-286
A carcinogen, 2-amino-1-methyl-6-phenylimidazo [4,5-b]-pyridine (PhIP), has been measured in airborne particles, diesel-exhaust particles, and incineration ash from garbage-burning plants. PhIP was found in all kinds of samples. In the light of the present results, together with the previous findings that PhIP was present in cooked foods and cigarette smoke, PhIP is likely to be an ubiquitous environmental pollutant. These observations also suggest that PhIP may be formed through the combustion process. 相似文献
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Atsumi Miyake Hidefumi Kobayashi Hiroshi Echigoya Shiro Kubota Yuji Wada Yuji Ogata Hiroyuki Arai Terushige Ogawa 《Journal of Loss Prevention in the Process Industries》2007,20(4-6):584-588
To better understand the detonation characteristics of ammonium nitrate (AN) and activated carbon (AC) mixtures, steel tube tests were carried out for AN/AC mixtures of various compositions and different forms of AN (powdered, prilled, phase stabilized and granular), and the detonation velocity was measured. The powdered AN/AC mixtures gave higher detonation velocities than the other AN forms. For all the AN/AC mixtures, the experimentally observed detonation velocities at each loading density were far below the theoretically predicted values calculated by the CHEETAH code based on thermohydrodynamics, exhibiting so-called non-ideal detonation. The lowest detonation velocity of powdered AN/AC mixtures was obtained as D=1.25 km/s for an AC content of 0.1 wt%. This was considered to be close to the critical condition for stable detonation. 相似文献