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71.
对2种氰化物显色剂配制方法进行了对比,发现用无水乙醇配制的显色剂具有方便,经济,实用,无毒且显色剂保存期长等优势。 相似文献
72.
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74.
简述了塔山水库蓝藻暴发的过程及成因。指出 ,由于水库的营养物质增多、水质恶化 ,在不利的水文、气象 (高温、光照充足、微风 )等条件下 ,导致蓝藻暴发。提出了相应的控制对策 相似文献
75.
江苏省12大湖泊水环境现状与污染控制建议 总被引:5,自引:0,他引:5
江苏面积大于50km^2的12个湖泊的水质恶化、面积减少、富营养化、湖泊生态系统退化与湖泊受TP、TN的污染和围湖造田等有关。经济快速发展,第二产业结构偏重,排放污染的总量超过湖泊承载力,湖泊底泥释放N、P及入糊河流携带污染物为造成湖泊环境问题的根本原因。建议调整产业结构,执行严格的排放标准,围绕重点区域、重点行业、重点企业和重点污染源治理,由控制COD为主转为控制COD和N、P并重,引水调控水质,建立湖泊资源数据库和生态系统信息网络,开展湖泊污染物来源分析和富营养化机理研究,开展跨界区域统筹对湖泊综合治理。 相似文献
76.
Jie Liu Junjun Ma Weizhang Zhong Jianrui Niu Zaixing Li Xiaoju Wang Ge Shen Chun Liu 《Frontiers of Environmental Science & Engineering》2023,17(4):51
77.
Soon-Ung Park Moon-Soo Park Youngsin Chun 《Atmospheric environment (Oxford, England : 1994)》2010,44(38):4964-4972
A 20-m Asian dust monitoring tower was installed at Erdene in Dornogobi, Mongolia in later 2008, which is one of the high Asian dust source regions in the Asian domain, to investigate meteorological conditions for the dust events. The tower was equipped with meteorological sensors (temperature, humidity and wind speed at four levels, precipitation and pressure near the surface), radiation sensors (solar radiation, net radiation) and soil measurement sensors (soil moisture and soil temperature at three levels and soil heat flux at one level) and turbulent measurement (sonic anemometer) at the 8 m height and PM10 concentration measurement (beta guage) at the 3 m height. Measurement was made for a full year of 2009. The observed data indicated that dust events occur all year round with the maximum hourly mean maximum concentration of 4107 μg m?3 in the early May to a minimum of 92 μg m?3 in later August. It was found that the dust concentration at this site is directly related to the wind speed exceeding the threshold wind speed (likewise the corresponding friction velocity) during the winter to early spring. However, the observed dust concentration is not only related to the wind speed exceeding the threshold wind speed but also to the Normalized Difference Vegetation Index (NDVI) during the late spring to the late autumn due to the growth of vegetation. It was also found that the surface soil moisture content does not affect the dust concentration due to the relatively short residence time of the soil moisture in the surface soil. The presently monitored data can be used to verify parameters used in the Asian Dust Aerosol Model (ADAM) that is the operational forecasting dust model in the Korea Meteorological Administration (KMA). 相似文献
78.
Young Nam Chun Mun Sup Lim Kunio Yoshikawa 《Journal of Material Cycles and Waste Management》2012,14(1):65-73
A rotary drum dryer having an internal rotating body was designed and tested in this study. It was shown that the developed
dryer is effective for drying sewage sludge. The best operating conditions in the dryer were low energy input and almost 10%
moisture content. The conditions are 255°C for the rotary drum temperature, 17 min for the sludge residence time, and 55 kg/m3 h for the dryer load. Under these conditions, the drying efficiency was 84.8%. The average diameter of dried sludge was less
than 8 mm, and the weight reduction rate was 80%. Parametric screening studies achieved the following results. The drying
efficiency increased with the increase of the internal temperature and the sludge residence time in the rotary drum, while
the drying efficiency decreased when increasing the dryer load. In addition, it was shown that NH3 and CO2 were the primary components released from the sewage sludge drying process. The amounts of both of these components increased
when the rotary drum temperature was increased. 相似文献
79.
20 0 1 0 1 2 6印度西北部的普杰地区发生了 7 8级强烈地震。对这次强震事件 ,利用卫星遥感监测地气系统射出长波辐射的数值产品资料 ,分析了以普杰为中心整个西亚范围内 ,事件发生前后共计 6个月的月平均辐射场的分布特征及其演变过程。发现自震前 2个月至震时当月 ,普杰地区始终是一个辐射 (热 )场的高值中心 ,震后明显消散。据此认为印度大地震有可识别的预警信息 ,提出利用卫星遥感技术及其产品 ,有可能为“突破”短临地震预报开拓出一种新的预测技术生长点 相似文献
80.
研究零价铁(Fe^0)的除砷效果,试验考察了Fe^0投加量、接触时间、pH值、DO浓度、温度、腐殖质、竞争性阴离子(SO4^2-,NO^3-,SiO2^3-,H2PO3^-,HCO3^-)对Fe^0除砷效率的影响。结果表明,Fe^0(80目)投加量为2g/L,接触时间180min,pH值为6.5,DO值6.5mg/L的条件下,对质量浓度为1mg/L的含砷水样,Fe^0对As(Ⅴ)的去除率高达96.5%,而对As(Ⅲ)的去除率只有75.8%。降低水样pH值或提高DO可显著提高Fe^0的除砷效率,温度对Fe^0除砷影响不大,水体中的腐殖质、磷酸盐、硅酸盐的存在会由于竞争性吸附而导致Fe^0除砷效率下降。采用Fe^0颗粒去除饮用水中的砷高效、经济,具有良好的应用前景。实际应用中,对于DO值较低的地下含As水,可通过充氧提高Fe^0除As效率。当水体中腐殖质、磷酸盐或硅酸盐浓度较高时,应考虑采取相应的预处理措施。 相似文献