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高锰酸钾——硫酸——过硫酸钾消化冷原子荧光法测定总悬浮颗粒物中… 总被引:1,自引:0,他引:1
测定环境大气悬浮颗粒物中痕量汞,用4种消化液进行对比实验,其中高锰酸钾-硫硫-过硫酸钾混合液消化效果较好,用冷原子荧光测定操作简便,检测下限为0.05μg/L,重复测定9个实际样品,相对标准偏差为11.6%,变异系数为10.4%,添加汞标准回收率为102%。 相似文献
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高效液膜分离富集测定微量铜 总被引:1,自引:0,他引:1
应用高效乳状液膜技术分离、富集水和土壤样品中微量铜(Ⅱ).研究了流动载体(P204)、表面活性剂(SPan80)、膜的增强剂(液体石蜡)、膜溶剂(煤油)和内相解吸剂(2.5mol/LH2SO4)等液膜体系,对分离富集微量铜(Ⅱ)的影响.确定了Span80—P204─液体石蜡─煤油─H2SO4高效液膜体系的最佳组成和最适宜的实验条件.富集后的溶液用1-(2-吡啶偶氮)-2-萘酚(PAN)分光光度法测定铜(Ⅱ).用本法富集水和土壤中微铜(Ⅱ).回收率在99%以上。应用于测定水和土壤中的微量铜.相对标准偏差为1.2%~4.5%。 相似文献
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对4─氨基安替比林氯仿萃取比色法测定水中的挥发酚,如何更好地降低空白值作了介绍,阐述了对显色剂不同的提纯方法,并对各种方法作了合理的分析、评价.找出了一种既能降低测定空白值,又不影响方法的灵敏度,并保证分析结果精密度和准确度的方法. 相似文献
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4L─44/2.5活塞式鼓风机系统的噪音控制吕鹏民(新疆克拉玛依炼油厂沥青车间834000)1车间噪声的调查车间现有4L—44/2.5活塞式鼓风机4台,4台机子可并联运行向同一储气罐供压缩空气。通常情况下用一台机子就能满足需要,每两台机子共用一个储气... 相似文献
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原子荧光光谱法测定废水样品中的汞 总被引:1,自引:0,他引:1
应用AFS-220型双道原子荧光光谱仪,研究了有色冶炼废水样品中汞的测定技术。将废水样品以适量硝酸酸化,加入高锰酸钾使汞成为离子状态,再以硼氢化钾(KBH4)为还原剂,在硝酸介质中测定汞,回收率为91~95%,最低检出限可达0.0002μg/ml。 相似文献
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朱明 《环境监测管理与技术》1995,(5)
Ag─DDC法测砷的几条经验朱明(江苏省江都市环境监测站225200)用Ag-DDC法测定砷,在做校准曲线或测定较多水样时,需按方法[1]的要求预先称取多份一定量(4g)的无砷锌粒,分装备用,这不仅繁琐费时,且在加锌粒时还容易出错。用粗略法加锌可以弥... 相似文献
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Composted organic wastes have been shown to reduce emissions of N2O and CH4, but little is known about the release of these gases during the composting process. This research examined the emissions of N2O and CH4 during the composting of liquid swine manure and wheat straw at two operations, one with forced aeration and the other without. The lack of aeration increased CH4 emissions to 24 times that of composting with aeration, but had no significant effect on N2O production. When total N2O and CH4 emissions from composting were compared with liquid swine manure emissions, aerated composting was found to reduce emissions to as low as 30% of those from liquid manure storage, while non-aerated composting elevated emissions up to an estimated 330% of liquid manure storage. 相似文献
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Ekeberg D Ogner G Fongen M Joner EJ Wickstrom T 《Journal of environmental monitoring : JEM》2004,6(7):621-623
A method for determination of the climate gases CH4, CO2 and N2O in air samples and soil atmosphere was developed using GC-MS. The method uses straightforward gas chromatography (separation of the gases) with a mass spectrometric detector in single ion mode (specific determination). The gases were determined with high sensitivity and high sample throughput (18 samples h(-1)). The LOD (3sigma) for the gases were 0.10 micro L L(-1) for CH4, 20 microL L(-1) for CO2 and 0.02 microL L(-1) for N2O. The linear range (R2 = 0.999) was up to 500 microL L(-1) for CH4, 4000 microL L(-1) for CO2 and 80 microL L(-1) for N2O. The samples were collected in 10 mL vials and a 5 microL aliquot was injected on column. The method was tested against certified gas references, the analytical data gave an accuracy within +/-5% and a precision of +/-3%. The presence of < or = 10% by volume of C2H2 (often used experimentally to prevent N2 formation from N2O) did not interfere with detection for the targeted trace gases. 相似文献
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Greenhouse gases are more sampled than ever because of environmental interests. Gas samples are often inserted into vials with gas tight butyl rubber septa before concentration analysis. Little is known on the global transfer property of butyl rubber septa for CO2, N2O and CH4. Sorption kinetics were measured by injecting CO2, N2O or CH4 into glass vials with either one of four butyl rubber septa types and stored during 90 days. CO2 and N2O concentrations decreased during storage depending upon septa type and initial concentration, with the highest linear rate being 0.023 for CO2 and 0.0015 mg L(-3) day(-1) for N2O. When a low concentration was injected, CH4 concentration changes over time were small and did not differ between septa types. Sorption isotherms were measured using nine concentrations and stored during 45 days. CO2 sorption isotherms ranged from 0 to 3.7 x 10(-3) m(3) m(-2) and N2O from 0.3 to 1.4 x 10(-3) m(3) m(-2). Examples of errors associated with the use of these butyl rubber septa are given. 相似文献
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B. Beck-Friis M. Pell U. Sonesson H. Jönsson H. Kirchmann 《Environmental monitoring and assessment》2000,62(3):317-331
Composting can be a source of N2O andCH4 production. In this investigation, differentcompost heaps of organic household waste weremonitored with the focus on potential formation ofCH4 and N2O in the heaps and emission ofthese gases from the heaps. The studied compost heapshad different compost ages, turning intervals andcompost sizes. The analysed compost gases containedbetween 1–3421 L of N2O-N L-1 and 0–470 mL of CH4 L-1. The emission rates ofN2O and CH4 from the compost heaps werebetween 1–1464 mg N2O m-2 day-1 and0–119 000 mg CH4 m-2 day-1. These verylarge differences in compost gas composition andemission indicate the importance of compostmanagement. The results also give an understanding ofwhere in the composting process an increasing emissionof N2O and CH4 can occur. 相似文献
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Recep Kulcu Kamil Ekinci Fatih Evrendilek Can Ertekin 《Environmental monitoring and assessment》2010,167(1-4):545-558
This study quantified spatiotemporal patterns of CH4 and N2O emissions from livestock and poultry production in Turkey between 1961 and 2007. CH4(enteric) (from enteric fermentation), CH4(manure) (from manure management), and N2O(AWM) (from animal waste management) emissions in Turkey were estimated at 1,164, 216, and 55 Gg in 1961 and decreased to 844, 187, and 39 Gg in 2007, contributing a share of roughly 2% to the global livestock-related CH4 emissions and %1.5 to the global N2O(AWM) emissions, respectively. Total CO2-eq emissions were estimated at 50.7 Tg in 1961 and declined from a maximum value of 60.7 Tg in 1982 to a minimum value of 34.5 Tg in 2003, with a mean emission rate of 48 Tg year???1 due to a significant reduction in the number of ruminant livestock. The highest mean share of emissions belonged to West Black Sea (14% and 16%) for CH4(enteric) and CH4(manure) and to North East Anatolia (12% and %13) for N2O(AWM) and total CO2-eq emissions, respectively. The highest emission density was 1.7 Mg km???2 year???1 for CH4(enteric), 0.3 Mg km???2 year???1 for CH4(manure), and 0.07 Mg km???2 year???1 for the total CO2-eq emissions in the West and North East Anatolia regions and 0.09 Mg km???2 year???1 for N2O(AWM) in the East Marmara region. Temporal and spatial variations in CH4(enteric), CH4(manure), and N2O(AWM) emissions in Turkey were estimated using regression models and ordinary kriging at a 500-m resolution, respectively. 相似文献
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建立了酸性条件下,以MnSO4代替Ag2SO4作催化剂快速测定水中COD的方法.考察了K2Cr2O7用量、MnSO4用量、H2SO4浓度、消解温度、消解时间等因素的影响,确定了最佳试验条件和最佳测定范围.方法精密度和准确度均能满足测定要求,与重铬酸钾法作对比试验,测定结果基本一致. 相似文献
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采用高效液相色谱二极管阵列检测器同时测定化妆品中二苯酮-2、二苯酮-3与甲氧基肉桂酸乙基己酯,以乙腈和水为流动相梯度洗脱,335 nm为检测波长,以保留时间和紫外光谱特征定性,外标法定量。3种化合物在1.00 mg/L~150 mg/L范围内线性良好,最低检出质量分数均为0.015%,基质加标平均回收率为96.2%~117%,RSD为0.2%~1.0%。 相似文献
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介绍了国内外二氧化碳( CO2)气体检测方法,选取红外传感器、非分散红外和气相色谱3种方法监测工业燃煤废气中的CO2。试验结果表明,3种方法的精密度和准确度均满足要求;单一燃煤废气中CO2的体积分数范围为6.70%~15.10%,同一排气筒中CO2体积分数5 min的波动范围为0~22.4%;同一排气筒(单一燃煤废气)中CO2和O2的体积分数有一定的关联性,二者之和基本稳定在19%~21%范围;非分散红外法和气相色谱法测定同一样品的相对偏差为0.9%~3.4%;红外传感器适用于有组织排放的现场监测,另2种方法适用于无组织废气和环境空气监测。 相似文献
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Marković DM Marković DA Jovanović A Lazić L Mijić Z 《Environmental monitoring and assessment》2008,145(1-3):349-359
O(3), NO(2), SO(2), CO and PM(10) concentrations, simultaneously determined for the first time in Belgrade urban area in the autumnal period of 2005, are presented. The obtained results display similar behaviour of SO(2), NO(2), CO, PM(10) opposite from that of O(3). The weekend effect was also investigated showing diminution of average daily concentrations of SO(2), NO(2), PM(10) and CO for 72, 40, 37 and 42% respectively, and increase of the average daily concentration of O(3) for 56%. Influence of meteorological conditions on observed concentration levels was studied, too. The observed influence of wind speed on the O(3) nightly concentration levels was analyzed pointing to the phenomena of O(3) transport during episodic measurements. To make an identification of possible pollution sources and analyse the influence of meteorological parameters on pollution levels, air back trajectories for high level concentrations episodes were calculated and analysed. A multivariate receptor modelling (Principal Component Analysis, Cluster Analysis) has been applied to a set of data in order to determine the contribution of different sources. It was found that the main principal components, extracted from the air pollution data, were related to gasoline combustion, oil combustion and ozone transport. 相似文献