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721.
土壤环境中的硝基苯是难于检测的一类化学污染物。本研究以受到硝基苯污染的松花江水灌溉的哈尔滨流域的农田为研究对象,采用"微波萃取-气相色谱法",研究了模拟受到硝基苯污染土壤环境中的硝基苯含量和实际检测了松花江水灌溉的农田的硝基苯,研究了微波消解和气相色谱测定条件。结果显示:1.0mg/L~15.0 mg/L范围内线性良好,硝基苯的最低检出限为0.012,回收率为92.4%~99.4%。松花江流域农田土壤硝基苯含量未检出,即没有硝基苯污染。  相似文献   
722.
硫化矿尾矿酸性矿山废水污染及释酸能力预测评价方法   总被引:3,自引:0,他引:3  
酸性矿山废水是全球矿山面临的最严重的环境问题之一。文章介绍了评价硫化物尾矿产酸潜力的2种方法,即静态溶浸测试和动态淋滤测试。静态溶浸测试包括酸碱估算法和净酸生成法2种。还探讨了2种方法所存在的问题和局限性,并对进一步的研究进提出了设想。  相似文献   
723.
顺德区甘竹罐头食品有限公司二期污水处理工程设计处理能力为400吨/日,该工程采用上升流水解(酸化)-序列间歇式活性污泥法(SBR)新工艺,操作简单、运行稳定、效果优良、处理后水质达到中华人民共和国《肉类加工工业水污染物排放标准》(GB 13457-92)一级排放标准要求。本文按工艺流程介绍了系统中各构的设计参数、设备配置情况及半年来的运行体会,并对存在的问题进行了分析,提出了改进措施。  相似文献   
724.
本文选用污染损失率法初步估算了贵州兴仁煤矿废水灌溉区的土壤重金属污染损失率和重金属污染经济损失量。计算数据显示,环境污染所造成的经济损失约为339.58万元。研究区40%的土壤处于严重污染状态,呈现出R(As)〉R(Cu)〉R(Zn)〉R(Pb)的关系,综合污染损失率与元素As的单元素污染损失率表现出极高的相关性,反映出As是造成研究区重金属污染的主要污染元素。  相似文献   
725.
贾祥焱 《环境保护科学》2011,37(5):56-58,66
探讨了通过气相色谱仪双通道检测室内空气中总挥发性有机化合物的可行性.建立了前、后双通道的苯、甲苯、乙酸丁酯、乙苯、苯乙烯、对(间)二甲苯、邻二甲苯、正十一烷等9种典型有机污染物的外标曲线,各组分相关系数R2为0.9995~1,并通过各自的标准曲线来计算其标样考核结果,对比标样真实浓度值,验证前、后双通道的准确性以及相互...  相似文献   
726.
There is concern about environmental impacts of cropping in catchments of Australia's Great Barrier Reef, especially losses of nitrogen (N) from cropping systems. Sugarcane production in the Burdekin region in the dry tropics stands out from other crops/regions because it is grown with the highest applications of irrigation water and N fertiliser rates of any sugarcane producing region in Australia, attributes which may enhance losses of N. Little is known about N losses from sugarcane production systems, especially irrigated systems. We measured parts of the water and N balance over three sugarcane crops at three contrasting sites in different parts of the Burdekin region, covering a range of soil types/textures and irrigation managements. The experimental data were used to parameterise the APSIM-Sugarcane cropping systems model, and the model then used to ‘infill’ missing data and develop more complete water and N balances for each of the crops at the three sites. The model was also used to simulate long-term yields and N losses through runoff and leaching below the root zone at the sites under a range of N fertiliser and irrigation management practices. Unlike the experience in other cropping systems, N losses through runoff and leaching below the root zone were not higher at our sites than measured in rainfed sugarcane production systems. The long-term simulations showed there were clear opportunities for reducing N losses while maintaining yields through reducing N fertiliser application rates. Simulations results suggested that long-term N surpluses of 50 kg ha−1 yr−1, considerably less than those during the experiment or common in the study region, were sufficient to maintain yields but reduce N losses by 50-57%. So, N fertiliser management should aim to keep surpluses to that level. Improved irrigation management could also help reduce N losses but generally to a much lesser extent than reduced N fertiliser applications. Research is required to confirm these predicted benefits, and investigate potential interaction between N fertiliser and irrigation management practices, and impacts of other management practices.  相似文献   
727.
Methanol is the most widely used natural gas hydrate inhibitor and it is only effective as a hydrate inhibitor in the aqueous phase. Methanol is not regenerated in natural gas inhibition process due to its intermittent application in most cases. However, a significant cost is associated with the process because of methanol loss while utilizing this inhibitor. In this work, several intelligent models along with a new mathematical correlation are presented in terms of methanol concentration in aqueous phase and temperature to precisely forecast the methanol loss in the saturated hydrocarbons phase. An excellent match was noticed between the calculated results and literature data.  相似文献   
728.
探明煤层的展布情况和隐伏的地质构造对煤矿的安全生产至关重要。基于大量的瓦斯抽采钻孔的数据,提出了利用瓦斯抽采钻孔预测煤层隐伏构造的方法。通过现场记录钻孔基础数据,运用全角全距法求出钻孔在煤层(顶)底板控制点三维坐标,并建立数据库;利用Surfer数据内插和图形处理功能,绘制煤层顶(底)板三维模型、等值线图和残差图,实现煤层的可视化;根据等值线的疏密异常变化圈出煤层中存在的隐伏构造位置,采用数学地质分析方法判断隐伏构造的类型。通过在古汉山矿1603工作面的试验,证明该方法预测煤层隐伏构造切实可行。  相似文献   
729.
基于某尾矿库目前标高和最终标高的概化模型,在正常水位和洪水位两种工况下,采用GeoStudio软件中的SEEP/W模块进行渗流场模拟,并应用SLOPE/W模块对每种条件下尾矿坝的稳定性进行数值计算,得到最危险滑动面和最小抗滑稳定系数。结果表明,在排渗设施正常工作的情况下,尾矿坝边坡稳定性均满足规范要求的最小安全系数,但终高洪水位时坝体安全系数的富余不是很大。同时验证了尾矿坝安全系数随着库内水位的上升以及浸润线深度的变化规律。  相似文献   
730.
Straight, trapezoidal‐shaped surface drainage channels efficiently drain the soil profile, but their deviations from natural fluvial conditions drive the need for frequent maintenance. Ecological and socioeconomic impacts of drainage ditch maintenance activities can be significant, leading to harmful algal blooms and increased sedimentation. We developed a two‐stage ditch design that is more consistent with fluvial form and process. The approach has potential to enhance ecological services while meeting drainage needs essential for agricultural production. We studied geomorphic change of the inset channel, benches and banks of seven two‐stage ditches in Ohio, Indiana, and Michigan. Three to 10 years after construction, inset channel changes reflected natural adjustments, but not all ditches had reached their quasi‐equilibrium state. Ditches had experienced both degradation and aggradation on the benches at a rate of 0.5‐13 mm/yr. Aggradation on the benches was not likely to threaten tile drain outlets. Localized scour was observed on the banks at some sites, but at all but one site changes were not statistically significant. Except for the removal of woody vegetation, none of the ditches required routine maintenance since construction. Two‐stage ditches can be a stable, viable option for drainage ditch management if designed and installed properly on the landscape.  相似文献   
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