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应用溶解氧值确定含煤河水BOD_5稀释倍数

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华北地质矿产杂志 1996年第2期11卷 300-304页

作者：丁超美赵香秀文志红阳泉市环境保护监测站

应用溶解氧值确定含煤河水ＢＯＤ_５稀释倍数丁超美，赵香秀，文志红（阳泉市环境保护监测站）１含煤废水的特殊性ＢＯＤ５的测定是一种经验的生物实验方法。测定样品的关键是稀释倍数的确定。稀释倍数过大或过小，将使五日需氧量太少... 详细信息

应用溶解氧值确定含煤河水ＢＯＤ_５稀释倍数丁超美，赵香秀，文志红（阳泉市环境保护监测站）１含煤废水的特殊性ＢＯＤ５的测定是一种经验的生物实验方法。测定样品的关键是稀释倍数的确定。稀释倍数过大或过小，将使五日需氧量太少或过多，超出耗氧量范围使实验失败。?..

关键词：河水含煤 DOD5 稀释倍数污染溶解氧值

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关于地面水中溶解氧值稳定性的探讨

贵州环保科技 1999年第2期5卷 47-48页

作者：胡水景淳安县环境保护监测站淳安311700

水体中溶解氧值不稳定,但变化有规律。一天中昼间上升,夜间下降;垂向随水深的增加而减小。提出了瞬时溶解氧值缺乏代表性的观点。

关键词：地面水溶解氧值变化规律氧值稳定性

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深水湖泊溶解氧值稳定性探讨

中国环境监测 2001年第6期17卷 62-62页

作者：胡水景淳安县环境监测站浙江淳安311700

通过对千岛湖水体溶解氧值的监测研究表明,水体中的溶解氧值不稳定,在一天之中有较大的波动范围,最低值出现在早晨日出之前,最高值出现在下午日落之前,水样极差夏季为3.21mg/L,冬季为2.78mg/L;垂向分布不均匀,溶解氧值随水深的增加而减... 详细信息

通过对千岛湖水体溶解氧值的监测研究表明,水体中的溶解氧值不稳定,在一天之中有较大的波动范围,最低值出现在早晨日出之前,最高值出现在下午日落之前,水样极差夏季为3.21mg/L,冬季为2.78mg/L;垂向分布不均匀,溶解氧值随水深的增加而减少,即表层为峰值,底层为谷值,在水深为80m的水体中,极差夏季为1.41mg/L,冬季为1.15mg/L.由此可见,深水湖泊水体中的溶解氧分布无论在时间上还是在空间上都有较大的差别.在水环境质量监测中,每一水期对每一点位的溶解氧仅作两次监测,且每点次的采样时间又不一致,用这样的两次瞬时值来代表某一水期某一水域的溶解氧,缺乏代表性.建议国家在修订地表水时予以明确规定溶解氧的采样时间和采样层次.

关键词：深水湖泊溶解氧值稳定性水质监控

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关于MBR去除率影响因素的研究

江西化工 2010年第4期26卷 53-57页

作者：韩雨华李闽霞江西融汇环保技术有限公司

溶解氧对MBR去除率的影响很大,把反应池中溶解氧值控制在0.8～1.2mg/L能达到最佳的去除效果。最合适的碳氮比介于10/1～20/1之间。进水氨氮浓度过大也会影响水中微生物的生化活性,使污泥浓度降低,从而造成系统去除率降低。

关键词： MBR 去除率溶解氧值进水氨氮浓度污泥浓度生化活性去除效果微生物碳氮比反应池响水系统控制

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硝化-反硝化工艺中溶解氧的测定

河南科技 2009年第3期28卷 40-40页

作者：李笑芳邱洪森高俊解玉丽安钢集团公司焦化厂

安钢焦化废水处理中溶解氧的测定一直采用比较经典的碘量法，但随着新生物脱氮的开工，该方法出现了滴定终点不明显，溶解氧值高达几十的现象。通过实验比较，我们采用膜电极法来测定溶解氧。实验证明，膜电极法适用于焦化废水中的溶解... 详细信息

安钢焦化废水处理中溶解氧的测定一直采用比较经典的碘量法，但随着新生物脱氮的开工，该方法出现了滴定终点不明显，溶解氧值高达几十的现象。通过实验比较，我们采用膜电极法来测定溶解氧。实验证明，膜电极法适用于焦化废水中的溶解氧的测定。

关键词：溶解氧值硝化工艺测定焦化废水处理膜电极法生物脱氮滴定终点实验比较

Diel Vertical Distribution of Zooplankton in Lake Baringo, Kenya

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生命科学：英文版 2014年第5期8卷 447-460页

作者： Reuben Omondi Andrew W. Yasindi Adiel M. Magana Kenya Marine & Fisheries Research Institute Kisumu 40100 Kenya Department of Biological Sciences Egerton University Egerton 20115 Kenya Department of Biological Sciences Chuka University College Chuka 60400 Kenya

Diel zooplankton samples were obtained at a 4-m-deep central station on two sampling occasions in January and February, 2010 in Lake Baringo. Sampling was done at 1 m interval every four hours for 24 hours from 8:00 am to 04:00 am. Ten litres of lake water was collected by a Van Dorn sampler and sieved through a 50 μm mesh sieve and organisms in the entire sample counted. Concurrently, physico-chemical factors including temperature, pH, conductivity and dissolved oxygen were measured at the same depths in situ. In both sampling months, the temperatures were higher during the day when stratification was observed just below the 1 m depth. This was, however, broken by diurnal winds in the evenings. PH and dissolved oxygen values followed the same trend but conductivity was generally uniform. In contrast to what has been observed in clear water lakes, the densities of Lake Baringo zooplankton were generally higher at the surface waters during the day while during the night the organisms were distributed throughout the lake column, a phenomenon which could be attributed to the high waters turbidity. The Proximity of zooplankton to the euphotic zone during the day provides them with feeding opportunities on phytoplankton.

关键词：浮游动物垂直分布昼夜肯尼亚溶解氧测定生物计算化学因素溶解氧值

Characteristics, Constraints and Perspectives of the Fish Farming in Burundi

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Journal of Environmental Science and Engineering(B) 2015年第5期4卷 240-249页

作者： Charles Niyonkuru Emile Nibona Jacques Moreau Department of Biology Institute of Applied Pedagogy University of Burundi Bujumbura 5223 Burundi Department of Aquatic Environment Institute of National Polytechnique/Ecole Nationale Supdrieure Agronomique ToulouseAuzeville Tolosane 31326 France

The fish farming was introduced in Burundi in about 1950s. Actually, several fish ponds were abandoned and many others were still unproductive. This study aims to present current state and perspectives of the fish farming for its real contribution to the socio-economic development. The results presented are compilation of physical and chemical parameters series measured in fish ponds and inquiries led in 2010-2014 to the fish farmers in seven provinces (40% of the total area of the country). Weak values of some physical and chemical parameters showed that the majority of ponds are badly maintained. Thus, the dissolved oxygen values varied between 0.2 mg/L and 3.5 mg/L. The high relinquishment rate of the fish farming (between 40% and 67% according to the provinces) could be explained by many constraints: no centers of fish farming breeding for various fish species and no production center of complete foods with local sub-products. About 75% of fish famers confirmed that they have never benefited framing in fish farming. In spite of the diverse constraints, Burundi has a dense rivers system with favorable physical and chemical parameters and many appropriate sites for the fish farming. Thus, the main suggestions concern the sector reorganization.

关键词：鱼类养殖社会经济发展化学参数生产中心养鱼户溶解氧值河流系统鱼养殖