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401.
Abstact While male mammals seek to maximize access to potential mates, females maximize feeding efficiency. Ranging patterns are therefore often sex specific. Sex-specific ranging patterns have also been reported for East African chimpanzees and a recent study on female ranging patterns concludes that social organization is best described by a male-bonded community model, where females occupy individual home ranges that are distributed within the boundaries of the male-defended range. In West African chimpanzees, however, such sex-specific ranging patterns have not been consistently observed and a bisexually bonded community model, where both sexes use the entire home range equally, has been suggested to best describe social organization. In this study we analyze 5 years of data on individual ranging patterns of chimpanzees in the Taï National Park (Côte dIvoire) to test specific predictions of the different models of chimpanzee social organization. We found that although males in Taï had slightly larger home ranges than females, all individual home ranges and core areas overlapped highly. Small individual home range size differences were entirely due to the use of peripheral areas and were correlated with female social dominance. These findings strongly support the bisexually bonded community model for Taï chimpanzees. Thus, we conclude that there are fundamental differences in the space-use patterns of East and West African chimpanzees and discuss possible factors leading to such differences.Communicated by D. Watts 相似文献
402.
Legionella pneumophila, the causative agent of Legionnaires disease, is known to colonise and frequently grow in cooling tower waters. Disease is acquired by inhaling aerosol contaminated by legionellae. Determination of the count of Legionella pneumophila in cooling tower waters may, therefore, be useful for risk assessment. In our survey, 103 water samples from 50 cooling towers were examined over a five-year period to indicate the seasonal distribution and the ecology of L. pneumophila, as regards temperature and pH. L. pneumophila serogroup 1 was found in 44% of the isolated strains, which is primarily responsible for the majority of Legionnaires disease. The large majority of examined towers had levels of L. pneumophila in the high-risk category. These cooling towers have been linked to many outbreaks of Legionnaires disease. 相似文献
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城市污水回用于循环冷却水的探讨 总被引:3,自引:0,他引:3
对国内外城市污水回用循环冷却水的实践进行了详述,针对国内城市污水水质,推荐污水水质回用标准,并确立相应的工艺流程,期间还讨论了城市二级处理污水回用时要注意的问题。 相似文献
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采用先进水处理技术实现污水全面回用 总被引:1,自引:0,他引:1
抚顺石化公司洗化厂采用污水深度处理技术和先进的循环水处理技术-AEC及DIANIO(DⅡ),使大量污水作为补水水源,回用于循环水场、卫生冲洗、绿化等中水设施,创造了较好的节水减排效果。 相似文献
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天然锰砂去除工业冷却水中的锰、铁污染 总被引:2,自引:0,他引:2
采用天然锰砂滤料接触氧化法对去除工业冷却水中锰、铁的工艺条件进行了研究。滤料粒径05mm~10mm,滤床高800mm,滤速10m/h~12m/h,工作周期96h,反冲洗强度13L/m2·s,反冲洗时间5min~7min。出水Mn2+浓度达004mg/L以下。锰去除率80%以上,总铁浓度可达检验不出的水平。 相似文献
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大型冷却塔运行时有其特殊的环境要求 ,噪声治理有一定难度。现以南通某化工企业大型冷却塔噪声治理为例 ,对其位置、结构、机理和特性进行了探讨 ,阐述了一整套实用的控制措施。结果表明 ,方案严密、结构紧凑、造价低、降噪效果明显 ,该技术适用于同类型噪声的治理 相似文献