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431.
Forberg E Aarnes H Nilsen S Semb A 《Environmental pollution (Barking, Essex : 1987)》1987,47(4):285-291
Short exposure to ozone depressed photosynthesis in both oat and duckweed at concentrations above 140 microg m(-3) and 300 microg m(-3), respectively. The effect on exposed oat flag leaves was age-dependent, with maximum susceptibility to ozone 10-20 days after emergence of the panicle. In duckweed, photosynthesis was more sensitive to differences in ozone concentration than to differences in duration of exposure. 相似文献
432.
A saturated solution of pyrene in water was not toxic to the fish
, even in the presence of ultraviolet light. A survival curve possessing one minimum, and therefore defining two LC50 values, was obtained when fish placed in water containing increasing amounts of a pyrene solution in dimethylsulfoxide were exposed to ultraviolet light after a short incubation period. The phototoxicity was linked to the presence of undissolved pyrene. A normal survival curve with only one LC50 value was found when pyrene was solubilized with the surfactant Tween-20. Practically no phototoxicity was produced when the pyrene mixtures were filtered before use, or when a saturated aqueous solution of pyrene was used. Piperonyl butoxide, present at a concentration where it was not toxic, synergized the toxicity of pyrene
. The environmental significance of this observation may be considerable. 相似文献
433.
A new compartment, the terrestrial plant biomass, is proposed for inclusion in the fugacity model. Two possibilities of calculation have been developed and exemplified: the first considers the plant as a whole, the second takes into account foliage, trunk and roots separately. 相似文献
434.
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439.
Peter Orris M.D. John R. Kominsky M.S. Daniel Hryhorczuk M.D. James Melius M.D. 《Chemosphere》1986,15(9-12):1305-1311
A Polychlorinated Biphenyl (PCB) containing transformer released approximately 50 gallons of askarel oil. No polychlorinated dibenzofurans (PCDF) or polychlorinated dibenzodioxins (PCDD) were detected in a sample of the askarel (analytical limit of detection of 40 parts per billion per isomer group). Skin irritation, unusual tiredness, and headaches occurred in approximately 20% of the individuals at the scene of the incident. Serum PCB levels, and mean values for blood and urine tests were within normal ranges. 相似文献
440.