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R. H. M. Godoi D. Avigo Jr V. P. Campos T. M. Tavares M. R. R. de Marchi R. Van Grieken A. F. L. Godoi 《Water, Air, & Soil Pollution: Focus》2009,9(3-4):171-177
The promotion of good indoor air quality in schools is of particular public concern for two main reasons: (1) school-age children spend at least 30% of their time inside classrooms and (2) indoor air quality in urban areas is substantially influenced by the outdoor pollutants, exposing tenants to potentially toxic substances. Two schools in Curitiba, Brazil, were selected to characterize the gaseous compounds indoor and outdoor of the classrooms. The concentrations of benzene, toluene, ethylbenzene, and the isomers xylenes (BTEX); NO2; SO2; O3; acetic acid (HAc); and formic acid (HFor) were assessed using passive diffusion tubes. BTEX were analyzed by gas chromatography–ion trap mass spectrometry and other collected gasses by ion chromatography. The concentration of NO2 varied between 9.5 and 23?µg m?3, whereas SO2 showed an interval from 0.1 to 4.8?µg m?3. Within the schools, BTEX concentrations were predominant. Formic and acetic acids inside the classrooms revealed intermediate concentrations of 1.5?µg m?3 and 1.2?µg m?3, respectively. 相似文献
463.
Carvalho Barros Giselle Kalline Gomes Duarte Lindemberg Jesus Nogueira Melo Ricardo Paulo Fonseca Lopes Francisco Wendell Bezerra Barros Neto Eduardo Lins 《Journal of Polymers and the Environment》2022,30(6):2534-2546
Journal of Polymers and the Environment - The environmental impacts caused by dyes in industrial wastewater are incalculable, due to their adverse effects on the ecosystem and human life,... 相似文献
464.
Mating strategies and mating success of fallow (Dama dama) bucks in a non-lekking population 总被引:2,自引:0,他引:2
N. P. Moore P. F. Kelly J. P. Cahill T. J. Hayden 《Behavioral ecology and sociobiology》1995,36(2):91-100
The rutting behaviour of bucks in an enclosed population was investigated between 1988 and 1990. A substantial proportion of the matings were observed. After preliminary observations in the 1987 rut we categorised bucks into one of four rutting strategies based mainly on their degree of territoriality. We investigate the effects of age, dominance and mating strategy on mating success. Territories were aggregated in an area of oak woods and mating success was highly skewed. Bucks of between 5 and 7 years old achieved the majority (over 90%) of observed matings. Mating success was highly correlated with dominance but only weakly related to fighting success. The possession of a territory was crucial to achieving high reproductive success, with a 38-fold difference between the most and least successful strategies. Bucks pursuing the different strategies also differed in the time they commenced groaning, timing of matings, mating interference and the locations where they achieved their matings. Although high-ranking males devoted considerable effort to obtaining and defending a territory only 36% of each buck's matings were achieved on his territory and males tended to abandon these sites when the tendency of females to visit them decreased. 相似文献
465.
Lineage Loss in Serengeti Cheetahs: Consequences of High Reproductive Variance and Heritability of Fitness on Effective Population Size 总被引:1,自引:0,他引:1
Marcella J. Kelly 《Conservation biology》2001,15(1):137-147
Abstract: In natural populations, many breeders do not leave surviving offspring, and as a result many potential genetic lineages are lost. I examined lineage extinction in Serengeti cheetahs ( Acinonyx jubatus ) and found that 76% of matrilines were lost over a 25-year period. Production of future breeders was nonrandom and generally confined to a few families. Five out of 63 matrilines accounted for 45% of the total cheetah population over the course of the study. Lineage persistence is perhaps best illustrated by the variance in lifetime reproductive success ( LRS) and heritability in this parameter. In female cheetahs, variance in LRS was high, and new data show that this LRS was heritable. Variance in LRS and heritability in LRS have dramatic consequences for effective population size, N e . I calculated N e for cheetahs, taking into account fluctuating population size, unequal sex ratio, non-Poisson distribution of reproductive success, and heritability of fitness. The N e was most strongly affected by variance in reproductive success and especially heritability in reproductive success. The variance N e was 44% of the actual population size, and the inclusion of heritability further reduced N e to only 15% of the actual population, a ratio similar to that of a social carnivore with reproductive suppression. The current cheetah population in the Serengeti is below numbers suggested by N e estimates as sufficient to maintain sufficient genetic diversity. 相似文献
466.
Cláudia B. Lopes Joana R. Oliveira Luciana S. Rocha Daniela S. Tavares Carlos M. Silva Susana P. Silva Niels Hartog Armando C. Duarte E. Pereira 《Environmental science and pollution research international》2014,21(3):2108-2121
The technical feasibility of using stopper-derived cork as an effective biosorbent towards bivalent mercury at environmentally relevant concentrations and conditions was evaluated in this study. Only 25 mg/L of cork powder was able to achieve 94 % of mercury removal for an initial mercury concentration of 500 μg/L. It was found that under the conditions tested, the efficiency of mercury removal expressed as equilibrium removal percentage does not depend on the amount of cork or its particle size, but is very sensitive to initial metal concentration, with higher removal efficiencies at higher initial concentrations. Ion exchange was identified as one of the mechanisms involved in the sorption of Hg onto cork in the absence of ionic competition. Under ionic competition, stopper-derived cork showed to be extremely effective and selective for mercury in binary mixtures, while in complex matrices like seawater, moderate inhibition of the sorption process was observed, attributed to a change in mercury speciation. The loadings achieved are similar to the majority of literature values found for other biosorbents and for other metals, suggesting that cork stoppers can be recycled as an effective biosorbent for water treatment. However, the most interesting result is that equilibrium data show a very rare behaviour, with the isotherm presenting an almost square convex shape to the concentration axis, with an infinite slope for an Hg concentration in solution around 25 μg/L. 相似文献
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Using the 1993 crash of Amtrak's Sunset Limited in Mobile, Alabama, this study examines the safety education provided by seven newspapers. A total of 117 news stories were analysed for five primary themes: overall story category, passenger safety theme, train personnel safety theme, train safety theme and rescue safety. Sixty-three per cent were found to contain at least one safety theme paragraph within the larger story. A total of 631 paragraphs were identified as safety theme paragraphs, 32 per cent of which were passenger safety themes, 8 per cent were train personnel safety, 31 per cent were train safety and 29 per cent were rescue safety themes. As in previous research, safety themes rarely appeared alone; more often than not, a story contained a mixture of all themes. Some safety themes appeared more frequently than others, but overall, the safety themes present a complete view of the safety issues surrounding the crash.
Safety themes are embedded within a story framework which reflects the three stages of disaster news work. Images of normalcy tragically disrupted by the crash abound as do images of passengers escaping and aiding others. Disaster relief personnel and aviation officials are shown working to restore order and solve the mystery of the crash. Within this framework we can learn what to expect when a train crashes and what we might have to do in a similar situation. 相似文献
Safety themes are embedded within a story framework which reflects the three stages of disaster news work. Images of normalcy tragically disrupted by the crash abound as do images of passengers escaping and aiding others. Disaster relief personnel and aviation officials are shown working to restore order and solve the mystery of the crash. Within this framework we can learn what to expect when a train crashes and what we might have to do in a similar situation. 相似文献
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