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181.
邱瑞芳  奚旦立 《环境科技》2006,19(Z2):13-16
采用活性炭吸附做为海岛纤维开纤剥离废水直接酸析前的预处理,净化废水,提高回收TA的品质。对工艺条件进行了系统研究。以酸值、光密度和灰分为考核指标,设计正交实验,得出因素影响水平为:活性炭投入量>吸附温度>吸附时间>振荡速度,分析各因素对回收TA性能的影响趋势,建立回归方程。同时建立活性炭对废水中COD,TA的吸附理论模型(Langinulr和Freundlich等温方程),结果表明Freundlich等温方程能较好反应此吸附过程。  相似文献   
182.
活性污泥膨胀上浮的原因分析与对策   总被引:2,自引:0,他引:2  
污泥膨胀是活性污泥法污水处理的一个难题,尤其在处理高负荷的石化污水中。文章分析了引起污泥膨胀、上浮的主要原因,对引起污泥上浮的因素进行了探讨,提出了控制污泥膨胀、上浮的几种对策。  相似文献   
183.
黄澜 《云南环境科学》2000,19(Z1):262-264
采用共源点灰色聚类法对南渡江海口水域 1 993年枯水期水质进行评价 ,结论为I类水质。与共斜率灰色聚类法进行比较 ,该法更简化 ,加权含义更确切。  相似文献   
184.
活性污泥法快速培菌的探索与实践   总被引:4,自引:0,他引:4  
罗宁  洪焰 《环境与开发》2000,15(1):37-38,42
介绍了一种快速培养、驯活性微生物的方法,大大缩短了微生物生长的停滞期,使活性污泥在培菌,驯化方面有了很大的改进,做到节约时间、降低成本、减轻培菌期间的环境污染,使活性污泥法更加快速,高效。  相似文献   
185.
Two types of filter media in groundwater treatment were conducted for a comparative study of surface structure and catalytic performance. Natural filter media was adopted from a conventional aeration–filtration groundwater treatment plant, and active filter media as a novel and promising filter media was also adopted. The physicochemical properties of these two kinds of filter media were characterized using numerous analytical techniques,such as X-Ray diffraction(XRD), scanning electron microscope(SEM), energy dispersive X-ray(EDX), X-ray photoelectron spectroscopy(XPS) and Zeta potential. The catalytic activities of these filter media were evaluated for ammonium and manganese oxidation.XRD data showed that both active filter media and natural filter media belonged to birnessite family. A new manganese dioxide(Mn O2) phase(PDF#72-1982) was found in the structure of natural filter media. The SEM micrograph of natural filter media showed honeycomb structures and the active filter media presented plate structures and consisted of stacked particle. These natural filter media presented lower level of some trace elements such as calcium and magnesium, lower degree of crystallinity, lower Mn(III) content and lattice oxygen content than that of active filter media, which were associated with its poor ammonium and manganese catalytic activities. In addition, some γ-Fe2 O3 and Mn CO3 were found in the coating which may hinder the ammonium and manganese catalytic oxidation. This study provides a thorough and comprehensive understanding about the most commonly used filter media in water treatment, which can provide a theoretical guide to practical applications.  相似文献   
186.
对甲醛缓冲溶液吸收-盐酸副玫瑰苯胺分光光度法测定大气中二氧化硫的过程中应注意的问题进行了归纳总结,以提高测定结果的准确性。  相似文献   
187.
论文介绍了地震信号的去噪过程中,利用小波良好的时频局部化能力和多分辨率分析能力,对信号进行变换,利用变换后的幅值极大点检测出信号的奇异点(突变点,包含了震相和噪声),继而利用在不同的变换尺度下,震相信号和噪声模极大值的变化特征的不同来去除噪声.利用我台的地震信号进行验证,该方法去噪后震相更清晰,震相的标注信度更高.  相似文献   
188.
活性染料K-2BP在环境水体中的光解效应   总被引:8,自引:0,他引:8  
研究了活性染料K-2BP在TiO2存在下的光催化氧化分解。结果表明,影响光解过程的主要因素是染料浓度、催化剂TiO2的用量和pH。实验条件下,染料样液脱色率可达90%以上,将该法用于实际印染废水的处理,光照6h,脱色率可达70%以上。  相似文献   
189.
从研究活性炭所具有的孔隙结构出发,重点探讨防毒面具用活性炭的结构与防护性能的关系,明确了不同结构特性的活性炭对不同类型有毒气体防护机理与性能的差异,为科学选择防毒面具用活性炭提供了重要依据。文章还对体现活性炭孔隙结构的主要指标——孔容积的计算方法进行了探讨。  相似文献   
190.
Intensive study of arboreal forest-dwelling primates and their predators in Africa is increasingly revealing that crowned eagles (Stephanoaetus coronatus) are major predators of primates. Gray-cheeked mangabeys (Lophocebus albigena) are overrepresented in the diets of crowned eagles in Kibale National Park, Uganda, and adult male mangabeys are represented more than females. We focused on the behavior of adult male gray-cheeked mangabeys living in social groups in Kibale National Park (1) to clarify the interactions between mangabeys and eagles that might put adult males at greater risk and (2) to better understand individual variation in behavioral responses to predators. Adult male mangabeys in five groups responded to observer-confirmed presence of crowned eagles 88 times over a 13-month period. While all males gave alarm calls, only the highest-ranking male in each of four groups chased eagles. These males had elevated levels of fecal cortisol metabolites in the days immediately after they engaged in active defense, suggesting that they perceived such behavior as risky. In the one group where male ranks were unstable and there were no infants, no male was observed to chase eagles. We suggest that males pursue the dangerous tactic of chasing eagles only when they are likely to have offspring in the group. Males in larger groups also spent less time alarm calling to crowned eagles (from first to last call in a group), and our observations confirmed that the duration of their alarm calls was related to eagle presence. Thus, eagles spent less time around larger mangabey groups. Alarm calling by adult male mangabeys may signal to this ambush predator that it has been detected and should move on.  相似文献   
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