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Huangpu River is about 114.5 km from upriver Dianfeng to downriver Wusong,near the estuary of the Yangtze River.It plays a key role in supplying water for production,life,shipment and irrigation.With the industrial development,the pollution of the Huangpu River has become serious recently.The biological oxygen demand (BOD),total nitrogen (TN),total phosphorus (TP),oil,phenol and suspended solids (SS) were lower in the upstream sites than in the downstream sites,indicating pollutants being input along its course. Water quality was the worst in the Yangpu site,near the center of Shanghai City.Dissolved oxygen (DO) content was less than 2 mg/L in the site of Yangpu in July.Among relations between thirteen characteristics,relations between BOD,DO,TN,TP,NH_4~ -N, NO_3~--N and the count of total bacteria or Escherichia coli were significant and interdependent.Inner relationships between these main characteristics in the Huangpu River were studied.High nutrient concentration led to growth of microorganisms,including E.coli. Degradation of organic matters and respiration of bacteria made oxygen concentration decreased in the water body,and DO was a key factor for nitrification-denitrification process of nitrogen.In the Yangpu site,DO was decreased to less than 3.0 mg/L with BOD higher than 7.5 mg/L in May and July.Low DO concentration will decrease nitrification rate.Nitrification need at higher DO value than other organic substrate oxidation.Consequently,river water contains low NO_3~--N values with high amounts of TN and NH_4~ -N there.This will block the self-purification of surface water,by decreasing the rate of nitrification-denitrification transformation process in the water body. 相似文献
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叙述了用物理气相沉积技术制备的硬质耐腐蚀磨损防护涂层的研究进展。重点介绍了腐蚀磨损耦合工况特性和作用机理,单元、多元掺杂氮化物涂层,高熵氮化物涂层,多层、纳米多层、纳米复合、梯度氮化物涂层耐腐蚀磨损性能研究,非金属元素/金属元素掺杂DLC涂层、多层复合DLC涂层耐腐蚀磨损性能研究,并对涂层改性、强化机理和腐蚀磨损失效机制进行了总结。最后,提出了未来物理气相沉积硬质耐腐蚀磨损防护涂层重点发展的方向,应重点发展涂层组元/结构设计、力–电耦合损伤机理研究、高效率研发设计、涂层先进制备装备与评估体系等方面的能力。 相似文献
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The technology of steady combustion in a new type of rotary incinerator is firstly discussed. The formation and control of HCI,NOx and S02 during the incineration of sampled municipal organic solid waste are studied with the incinerator. Results showed that the new model of rotary incinerator can effectively control and reduce the pollutant formations by post combustion. 相似文献
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山西省辛安泉是长治地区的主要供水水源,目前它的部份泉城域已遭到了严重的氮污染,本文在环境水文地质地球化学调查的基础上,应用水文地球化学热力学理论,对氮化牧在岩溶水中转化方向,平衡组成进行了分析,并用稀释环境容量方法,作出了辛安泉氮污染预测初步评价。这表明在水文地质地球化学研究程度不足以建立溶质运移确定型模型时,水文地球化学方法是研究氮污染预测的一种有效的近似方法。 相似文献
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本文对近年来国内外有关氮化物迁移转化过程研究取得的新成果作了较为全面的叙述,包括氮化物在不同的生态系统中的硝化和反硝化的规律、转化的动力学以及数学模式等方面取得的研究成果 相似文献
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环境中氮化物迁移转化过程研究进展 总被引:5,自引:0,他引:5
本文对近年来国内外有关氮化物迁移转化过程研究取得的新成果作了较为全面的叙述,包括氮化物在不同的生态系统中的硝化和反硝化的规律,转化的动力学以及数学以得的研究成果。 相似文献
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本文在环境水文地质地球化学调查的基础上,以相似论为依据,采用模拟实验方法,获取NH4在水-岩土体系中的运移规律,进而建立实验拟合模型,经检验修正,可初步用于污染预测,这种把NH4的力学迁移与地球化学的融为一体的建模方法,具有合理,直观,简便等优点。 相似文献
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