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81.
为探究低氨氮生活污水亚硝化的可行性,采用高负荷生物滤池-上向流曝气生物滤池(UBAF)两段式反应器考察水流方向对高负荷生物滤池去除COD、氨氮效果及温度、DO对UBAF亚硝化效果的影响.结果表明,在水力负荷为0.58 m3/(m2·h)、COD容积负荷为2.30 kg/(m3·d)、气水比为3.6∶1、常温条件下,上向流进水方式能够获得稳定的低COD、高氨氮的二级出水.在水温30~33 ℃、DO 2.5~3.0 mg/L、进水pH 7.8~8.1条件下,UBAF出水氨氮平均转化率为84.58 %,亚硝氮平均质量浓度达23.01 mg/L.UBAF反应器中各种含氮化合物沿程变化及FISH检测表明,在反应器末段存在一定程度的同步亚硝化厌氧氨氧化作用.该两段式反应器能驯化单独的脱碳、脱氮优势菌群,实现低氨氮生活污水的亚硝化. 相似文献
82.
文章对电冰箱在线动态测试的系统功能、结构、测试通道、过程监控及判定等技术要求进行简要介绍,并指出其应用的优越性。 相似文献
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介绍了冰箱用硬质聚氨酸泡沫塑料(简称硬泡)的制备工艺,设计了冰箱用硬泡生产过程中的质量控制流程。实践证明,质量控制流程为保证生产提供了一套较完整、规范的管理方法。 相似文献
85.
1989年以来外商直接投资(FDI)对西安市的经济增长做出了极大的贡献。本文首先对外商直接投资与经济增长的关系进行了探讨,进而利用实证分析的方法分析了西安市的外商直接投资与经济增长的关系,最后通过计算要素的单位贡献率得出外商直接投资对经济增长的贡献从效率角度大大优于国内投资的结论。 相似文献
86.
In order to simplify the structure of the cold end of the pulse tube refrigerator (PTR) and have a better utilization of the cold energy of the system, a single stage four-valve pulse tube refrigerator (FVPTR) with a ‘L’ type pulse tube structure and two orifice valves at the hot end of pulse tube has been constructed. Verification experiments show that a two-orifice valve structure gives different adjustments to the gas flow rate of the hot end of the pulse tube than that of the one-orifice valve structure, a lowest temperature of 72 K was obtained at a frequency of 2.5 Hz under a system average pressure of 1.6 MPa with 200 mesh bronze screens as regenerator material, 20 mesh copper screens as stuffing material of heat exchanger. Due to the difficulty in manufacturing the thin ‘L’ type pulse tube, the wall thickness of the pulse tube in the experiment is relatively bigger than that of the ordinary pulse tube, which resulted in relatively big system loss and affected the minimum temperature of the system to a certain degree. 相似文献
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Effects of hydraulic retention time (HRT) and gas volume on efficiency of wastewater treatment are discussed based on a simulation experiment in which the domestic swage was treated by the two-stage-bio-contact oxidation process. The result shows that the average CODcr, BOD5 , suspended solid (SS), and ammonia-nitrogen removal rate are 94.5 %, 93.2 %, 91.7 % and 46.9 %, respectively, under the conditions of a total air/water ratio of 5 : 1 , an air/water ratio of 3:1 for oxidation tank 1 and 2:1for oxidation tank 2 and a hydraulic retention time of 1 h for each stage. This method is suitable for domestic sewage treatment of residential community and small towns as well. 相似文献
90.
Reviews the book Protecting children from domestic violence: Strategies for community intervention, edited by Peter J. Jaffe, Linda L. Baker, and Alison J. Cunningham (see record 2005-04430-000). The book emerged from the International Conference on Children Exposed to Domestic Violence that was held in London, Ontario in 2001. It begins with an excellent chapter by Jeffrey Edleson synthesizing the literature on the impact of exposure to domestic violence on children. Edleson's chapter is followed by two papers examining emerging assessments and treatment programs. The second section of the book addresses current thinking about individual and group intervention approaches. The third section of the book examines broader system level responses, including public awareness and school-based campaigns, as well as responses by the courts and police. This is a well-organized collection of papers that provides a good overview of the state of knowledge and innovative practice in an emerging field of practice. Protecting Children from Domestic Violence provides practitioners, policy makers, and researchers with an excellent overview of current knowledge and practices in working with children exposed to domestic violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献