共查询到20条相似文献,搜索用时 148 毫秒
1.
2.
3.
采用固相萃取-离子色谱法同时测定化工废水中乙醇胺、二乙醇胺、三乙醇胺、N-甲基二乙醇胺和N-丁基二乙醇胺等5种有机醇胺类化合物。通过试验,对固相萃取、离子色谱条件进行优化,优选C_(18)为固相萃取填料,使方法在1.10 mg/L~26.0 mg/L范围内线性良好,方法的检出限为0.72 mg/L~1.02 mg/L。废水样品3个质量浓度水平的加标回收率为84.0%~101%,测定6次结果的RSD为1.7%~12.0%。将该方法用于医药化工企业废水的测定,结果部分醇胺类化合物检出。 相似文献
4.
含铬废水中硫酸根常用浊度法测定,由于该方法操作严格且不太稳定,容易引起误差,加之废水本身带色,故本文改用原子吸收法间接测定,其回收率为94~102%,变异系数小于3%,能满足测定要求. 相似文献
5.
微波消解平台石墨炉原子吸收法测定活性污泥中重金属 总被引:10,自引:0,他引:10
以铜和铅为例建立了一种微波消解样品,平台石墨炉原子吸收法测定活性污泥中重金属含量的方法,该方法的样品加标回收率Cu为91 0%~97 3%,Pb为93 1%~98 0%,相对标准偏差RSD(%):Cu为1 38%~1 61%,Pb为1 28%~1 94%,检验限Cu为0 0052ng g,Pb为0 0073ng g,该方法应用于活性污泥中重金属的分析,实验所需时间短,取样量少,空白值低,实验过程中样品损失小,准确度和灵敏度高,结果令人满意。 相似文献
6.
镉汞齐法测定水中硝酸盐氮在美国“水和废水标准检验法”13版和15版中均有介绍,国内也有应用这个方法的报道.该法手续简单,快速,每小时可以测3~4个样品,方法灵敏度高,干扰因素少,适合在环境监测中应用.本法对大量样品操作并不理想.镉汞齐还原柱对硝酸盐的还原效率往往不足100%,因此在环境监测中如亚硝酸盐含量较高时,用现行镉汞齐法中提供的结果计算 相似文献
7.
原子荧光法测定废水中砷的不确定度评定 总被引:1,自引:0,他引:1
以原子荧光法测定油田废水中砷含量为实例,建立数学模型,分析和识别在分析过程中的不确定度来源,对测量中不确定度的各个分量进行了分步计算及合成,计算出测定结果的扩展不确定度0.74μg/L。通过计算和分析,结果表明,标准工作曲线拟合和方法回收率是原子荧光法测定油田废水中砷含量的不确定度的主要因素。 相似文献
8.
指出了亚甲蓝光度法测定洗涤剂的不足,提出改用甲基绿光度法测定,该方法快速简便,易于操作,相对标准差<5%,加标回收率在93%~104%之间。 相似文献
9.
10.
该法规定的检出范围是 6 0 mg/L~ 1 0 0 0 mg/L ,废水浓度高于 1 0 0 0 mg/L须定量稀释后测定 ,而低于 6 0 mg/L时 ,即使能准确测定也不能报准确结果 ,只能按 6 0 mg/L的一半报出。分光光度计在低吸光度时分值较宽 ,易分辨且催化快速法在COD浓度较低时曲线有很好线性关系 ,使得降低定量下限成为可能。实验表明 ,催化快速法测定CODcr的定量下限为 1 0 mg/L。这样 ,地表水、低浓度 CODcr的废水均可用快速法测定 ,扩大了该法应用范围 ,减轻了测定低浓度 CODcr使用经典回流法、密封消解法劳动强度 ,节省成本和时间。催化快速法测定COD… 相似文献
11.
采用HP-INNOWAX毛细管柱、气相色谱氢火焰离子化检测器测定工业废气和废水中的N,N-二甲基甲酰胺,可能共存的丙酮、乙醇和乙酰丙酮均对测试无干扰.方法在0.939 mg/L~75.1 mg/L范围内线性良好,对工业废水、无组织排放工业废气和有组织排放工业废气中N,N-二甲基甲酰胺的检出限分别为0.47 mg/L、0.16 mg/m3和0.31 mg/m3,标准溶液平行测定的RSD为1.9% ~2.2%,废水样品加标回收率为94%~ 97%. 相似文献
12.
13.
连续流动分析-分光光度法测定水和废水中总氮 总被引:1,自引:0,他引:1
吕清 《环境监测管理与技术》2014,26(1):42-45
对连续流动分析-分光光度法测定水和废水中总氮进行方法适用性验证,6家验证单位验证数据表明:方法在0 mg/L~10.0 mg/L范围内线性良好,相关系数为0.9996~0.9999;方法检出限为0.04 mg/L,测定下限为0.16 mg/L;6家实验室测定总氮标准溶液 RSD为0.4%~9.6%,测定总氮有证标准物质的结果在允许范围内,实际水样的加标回收率为92.0%~111%。该方法与国标方法同时测定多种类型的水样,结果无显著差异。探讨了影响该方法测定的干扰因素和消除方法,并提出方法应用要点。 相似文献
14.
John P. Bucci Michelle D. Shattuck Semra A. Aytur Richard Carey William H. McDowell 《Environmental monitoring and assessment》2017,189(8):406
Water quality impairment by fecal waste in coastal watersheds is a public health issue. The present study provided evidence for the use of a mitochondrial (mtDNA) marker to detect animal fecal sources in surface water. The accurate identification of fecal pollution is based on the notion that fecal microorganisms preferentially inhabit a host animal’s gut environment. In contrast, mtDNA host-specific markers are inherent to eukaryotic host cells, which offers the advantage by detecting DNA from the host rather than its fecal bacteria. The present study focused on sampling water presumably from non-point sources (NPS), which can increase bacterial and nitrogen concentrations to receiving water bodies. Stream sampling sites located within the Piscataqua River Watershed (PRW), New Hampshire, USA, were sampled from a range of sites that experienced nitrogen inputs such as sewer and septic systems and suburban runoff. Three mitochondrial (mtDNA) gene marker assays (human, bovine, and canine) were tested from surface water. Nineteen sites were sampled during an 18-month period. Analyses of the combined single and multiplex assay results showed that the proportion of occurrence was highest for bovine (15.6%; n = 77) compared to canine (5.6%; n = 70) and human (5.7%; n = 107) mtDNA gene markers. For the human mtDNA marker, there was a statistically significant relationship between presence vs. absence and land use (Fisher’s test p = 0.0031). This result was evident particularly for rural suburban septic, which showed the highest proportion of presence (19.2%) compared to the urban sewered (3.3%), suburban sewered (0%), and agricultural (0%) as well as forested septic (0%) sites. Although further testing across varied land use is needed, our study provides evidence for using the mtDNA marker in large watersheds. 相似文献
15.
Santosh K. Deshmukh Anil Kumar Singh Siba Prasad Datta K. Annapurna 《Environmental monitoring and assessment》2011,175(1-4):601-612
Impact of wastewater irrigation on some biological properties was studied in an area where treated sewage water is being supplied to the farmers since 1979 in the western part of National Capital Territory of New Delhi under Keshopur Effluent Irrigation Scheme. Three fields were selected which had been receiving irrigation through wastewater for last 20, 10 and 5 years. Two additional fields were selected in which the source of irrigation water was tubewell. The soil bacterial and fungal population density was studied in soil layers of 0?C15, 15?C30, 30?C60 and 60?C120 cm depths. Groundwater samples were collected from the piezometers installed in the field irrigated with sewage water for last 20, 10 and 5 years. Results indicate that there was significant increase in bacterial and fungal count in sewage-irrigated soils as compared to their respective control. The population density of bacteria and fungi in waste water-irrigated soils increased with the duration of sewage water application and decreased with increasing depth. The bacterial and fungal count was also directly proportional to organic carbon, sand and silt content and negatively correlated to the clay content, electrical conductivity, pH and bulk density of the soil. Groundwater under sewage-irrigated fields had higher values of most probable number (MPN) index as compared to that of tubewell water-irrigated fields. All the shallow and deep groundwaters were found to be contaminated with faecal coliforms. The vadose zone had filtered the faecal coliform to the tune of 98?C99%, as the MPN index was reduced from ??18,000 per 100 ml of applied waste water to 310 per 100 ml of groundwater under 20 years sewage-irrigated field. The corresponding values of MPN were 250 and 130 per 100 ml of shallow groundwater under 10 and 05 years sewage-irrigated fields, respectively. Rapid detection of faecal contamination suggested that the Citrobacter freundii and Salmonella were dominant in shallow groundwater, while Escherichia coli was dominant in deep groundwater collected from sewage-irrigated field. 相似文献
16.
17.
18.
19.
Solid waste samples were collected from five small-scale industrial sites in the National Capital Territory (NCT) of Delhi. These industrial sites represent the regional spread of the industrial belt in the NCT of Delhi. Solid waste samples were digested using aqua-regia and HF in air tight teflon bombs for the quantitative analysis of heavy metals (Hg, Pb, Cd, Mn, Fe, Ni, Cu and Zn) by GBC model 902 atomic absorption spectrophotometer. Hg was analysed using hydrid generator attachment. Beside this sequential extraction was used to fractionate five heavy metals (Pb, Ni, Cd, Cu and Zn) into six operationally defined phases, viz. water soluble, exchangeable, carbonate-bound, Fe-Mn oxides, organic-bound and residual fractions to ascertain the relative mobility of these metals. The result obtained showed metal concentration to be in the range of Hg 0.42-2.3; Pb 23-530; Cd 014-224; Mn 494-19 964; Fe 35 684-233 119; Ni 192-1534; Cu 3065-10 144 and Zn 116-23 321 (all units in mg kg(-1)) in all the industrial areas studied. The fractionated toxic metals like Pb, Ni and Cd were observed to be in the range of 25-35, 15-50 and 40-50%, respectively, in mobile or bio-available fractions of solid waste. As this waste is often disposed-off by the roadsides, low lying areas, abandoned quarries or in landfill sites which are often not properly planned, thus posing potential risk to ground and surface water quality to millions of people living downstream. 相似文献
20.
Pujari PR Nanoti M Nitnaware VC Khare LA Thacker NP Kelkar PS 《Environmental monitoring and assessment》2007,134(1-3):271-278
On-site sanitation is increasingly adopted in urban cities in India. The adoption of On-site sanitation system puts the groundwater
resources in the vicinity of the system at a greater risk. Microbial contaminants as well as chemical contaminants like Chloride
and Nitrate are generated from human waste. These contaminants travel through the medium and ultimately get in contact with
the groundwater. Hence, the groundwater sources are vulnerable to nitrate contamination near the On-site sanitation systems.
The present study indicates significant Nitrate and Chloride contamination in samples collected close to On-site sanitation
systems. The recommended limit set by the Bureau of Indian standards (BIS) limit of 45 mg/l for Nitrate concentration is also
exceeded in few samples. The study indicates that Bacterial as well as Nitrate contamination is more in Monsoon as compared
to Summer. 相似文献