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1.
苯酚-次氯酸钠示波极谱法测定水中微量氨   总被引:1,自引:0,他引:1  
在亚硝基铁氰化钾存在下,氨在氢氧化钠介质中与苯酚、次氯酸钠反应,其产物靛酚在滴汞电极上产生一灵敏的吸附波,NH3-N在0.003~0.22mg/L范围内,导数峰电流与其呈良好的线性关系.用于环境水中NH3-N的测定,其相对标准偏差小于3%,回收率在97%~105%之间,方法具有较好的选择性.  相似文献   

2.
3.
冷凝吸附法测定痕量挥发性含硫气体   总被引:2,自引:2,他引:2  
采用冷凝吸附法对痕量挥发性含硫气体的测定进行了研究 ,结果表明自行设计的冷凝吸附装置对于痕量挥发性含硫气体的富集有着良好的效果 ,富集效率可达 94%以上  相似文献   

4.
The levels of heavy metals were determined in the water of Bendimahi River Basin, statistically analysed and compared to natural gross radioactivity concentration. Fifteen samples of water were collected from Bendimahi River and Van Lake for two seasons in 2005. Water samples were analyzed for eight trace elements and concluded together with gross-alpha and gross-beta radioactivity concentrations. Atomic absorption spectrometry (AAS) was used to determine the concentrations of heavy metals in water samples collected from Bendimahi River basin. Correlation analysis was made for radioactivity and heavy metal concentrations and the Pearson correlation coefficients between gross-alpha and gross-beta radioactivity and heavy metal were determined. The concentrations of all metals were found to be higher than WHO, EC, EPA and TSE-266 guidelines for drinking water, except for Zn and Cu. Generally, the heavy metal concentrations in water samples obtained in May and in August were found to be in sequence of Fe>Zn>Pb>Cr>Cu>Mn>Co>Cd and Fe>Zn>Cu>Pb>Cr>Mn>Co>Cd, respectively. The gross-alpha and gross-beta activity concentration varies between 0.063 and 0.782, 0.021 and 0.816 Bq l(-1) in samples collected in May, and 0.009 and 0.037, 0.081 and 3.116 Bq l(-1) in samples collected in August.  相似文献   

5.
NH4NO3-Pd(NO3)2联合基体改进剂石墨炉法测海水中痕量镉   总被引:1,自引:0,他引:1  
用NH4NO3-Pd(NO3)联合基体改进剂,石墨炉法直接测海水中痕量镉.通过不同条件的实验,确定了最佳的分析条件;并通过对实际样品平行性和加标回收率的测定,验证了方法的精密度和准确度.建立了空白实验,在0.19~5.0μg/L线性范围内,镉的最低检出限为0.19μg/L.实验结果表明,该方法快速方便,提高了分析效率,准确度高,精密度好.  相似文献   

6.
Infrared spectrometry is a versatile basis to analyse greenhouse gases in the atmosphere. A multicomponent air pollution software (MAPS) was developed for retrieval of gas concentrations from radiation emission as well as absorption measurements. Concentrations of CO, CH4, N2O, and H2O as well as CO2, NO, NO2, NH3, SO2, HCl, HCHO, and the temperature of warm gases are determined on-line. The analyses of greenhouse gases in gaseous emission sources and in ambient air are performed by a mobile remote sensing system using the double-pendulum interferometer K300 of the Munich company Kayser-Threde. Passive radiation measurements are performed to retrieve CO, N2O, and H2O as well as CO2, NO, SO2, and HCl concentrations in smoke stack effluents of thermal power plants and municipal incinerators and CO and H2O as well as CO2 and NO in exhausts of aircraft engines. Open-path radiation measurements are used to determine greenhouse gas concentrations at different ambient air conditions and greenhouse gas emission rates of diffusive sources as garbage deposits, open coal mining, stock farming together with additional compounds (e.g. NH3), and from road traffic together with HCHO. Some results of measurements are shown. A future task is the verification of emission cadastres by these inspection measurements.  相似文献   

7.
This study compares the ambient air particulate matter (PM10) data of 15 different coal mine environments. For most of these mine environments, the monitoring was carried out by different researchers using respirable dust sampler (RDS) that separates PM10 by centrifugal inertial separation. At two sites — Padmapur and Ghugus (Chandrapur, Maharashtra, India) — mass inertial impaction-based sampler was used for PM10 monitoring. It is observed that the spatiotemporal average value of ambient air PM10 monitored using mass inertial impactor reports relatively higher values (240–372 μg/m3) compared to those monitored using RDS (<227 μg/m3). In order to realize the severity of mine area pollution, it is compared with PM10 values found in an urban area (Delhi, India). It is found that PM10 values in Delhi (using mass inertial impactor) are much higher (300–400 μg/m3) than those reported for the mine environment. The data seems to indicate that the mine environment is relatively cleaner than urban air and therefore raises doubt about the appropriateness of using either mass impactor or RDS for PM10 sampling.  相似文献   

8.
Noxious gases on ships are irritant pollutants that have potential impacts on the comfort and health of both livestock and humans. Identification of environmental influences on the pollutants will assist live exporters to control them. Ammonia, hydrogen sulphide and carbon dioxide, as well as wet and dry bulb temperature, dew point, air speed and depth of faeces that the sheep stood in, were measured on two ship voyages in which sheep were transported from Australia to the Middle East. Daily measurements were made at 20 measurement locations over 12 days. At four sites, the mean ammonia concentration for the voyage was above the recommended maximum limit for the live export industry (25 ppm). The mean ammonia concentrations at the remaining 16 sites were below 18 ppm and considered safe. High ammonia concentrations were localised and occurred particularly on closed decks, as well as at the front of the vessel and near the engine block on open decks. Ammonia concentration on the open decks was correlated with cumulative wind during the voyage, air speed, dew point, wet bulb temperature and faecal pad depth, and on the closed decks with dew point, and wet and dry bulb temperature. Hydrogen sulphide (<1.8 ppm) and carbon dioxide (<1900 ppm) concentrations were low and did not pose a risk to animal or human welfare or health. The results suggest that high ammonia concentrations occur in those parts of the ship where there is insufficient ventilation and/or high temperatures and humidity.  相似文献   

9.
Smart现场分析仪测定化学需氧量、氨氮   总被引:8,自引:0,他引:8  
对Smart现场分析仪测定化学需氧量、氨氮作了简单地介绍,并用实际水样与化学法进行了对比试验。测定结果表明,两者之间相对误差均在11%以内,较为一致。仪器体积小、携带方便,操作简单、快捷,试剂消耗少,可在现场从事应急监测。  相似文献   

10.
Ambient air quality has been an important issue for humans and the environment for hundreds of years. More recently, definitive links have been identified between pollutants and adverse effects on human health and on environmental sustainability. Of particular concern since the last quarter of the twentieth century has been the presence of toxic 'heavy metals' in ambient air. In order to measure the concentrations of pollutants, including 'heavy metals', in ambient air, to assess human and environmental exposure, comply with developing legislation, and assess newly introduced abatement strategies, the UK government established nationwide air quality measurement networks in the late 1970s. The nationwide measurement of 'heavy metals' in ambient air began in the late 1970s, and in 1980 was developed into several national networks, aimed at different metals and different emissions sources. These networks were rationalised into the current UK Heavy Metals Monitoring Network in 2003. The data produced by the current scientific operator of the Network, the National Physical Laboratory (NPL), in 2005, marked 25 years of ambient 'heavy metals' measurement in the UK at a nationwide level. This paper celebrates this milestone and provides a novel and critical examination of Network operations, measured concentration levels, and trends, over the last quarter of a century.  相似文献   

11.
吹脱-电导法测定水中氨氮及其自动分析仪   总被引:5,自引:0,他引:5       下载免费PDF全文
建立了吹脱-电导法测定水和污水中的氨氮的方法。该方法是在90℃温度下,以气体将水样中氨氮吹出,用5mmol/L硫酸吸收,吸收液电导率的方法,在一定浓度范围内与氨氮吹出量成正比。测定标准样品的相对标准差和相对误差均为2.7%,方法的精密度和准确度均较好。根据该方法原理研制的氨氮在线自动分析仪测定自行配制的氨氮标准溶液,相对误差在2.8%以内,测定值准确可靠,最低检出限为0.1mg/L,两台样机分别用于黄河边国家水质自动站测定地表水和济南水质净化一厂测定污水,经过约5个月的运转,情况良好。  相似文献   

12.
In this study, PM10 concentrations and elemental (Al, Fe, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pb, and Bi) contents of particles were determined in Düzce, Turkey. The particulate matter samplings were carried out in the winter and summer seasons simultaneously in both urban and sub-urban sampling sites. The average PM10 concentration measured in the winter season was 86.4 and 27.3 μg/m3, respectively, in the urban and sub-urban sampling sites, while it was measured as 53.2 and 34.7 μg/m3 in the summer season. According to the results, it was observed that the PM10 levels and the element concentrations reached higher levels, especially at the urban sampling site, in the winter season. The positive matrix factorization model (PMF) was applied to the data set for source apportionment. Analysis with the PMF model revealed six factors for both the urban (coal combustion, traffic, oil combustion, industry, biomass combustion, and soil) and sub-urban (industry, oil combustion, traffic, road dust, soil resuspension, domestic heating) sampling sites. Loadings of grouped elements on these factors showed that the major sources of the elements in the atmosphere of Düzce were traffic, fossil fuel combustion, and metal industry-related emissions.  相似文献   

13.
在全省城市环境空气质量监测网优化并运行六年的基础上 ,采用历史数据计算法对河南省环境空气质量监测网进行了优化。通过优化方法和监测项目的探索 ,确定了省控站数目 ,特别是提出了系统、完整的优化指标 ,优化结果是令人满意的。  相似文献   

14.
试验研究结果表明 ,轻质陶块附着生物膜后对废气的有机物的净化性能明显优于不锈钢环。轻质陶块完全可以取代常用的不锈钢环而成为生物膜填料塔的新型填料  相似文献   

15.
The use of alternative fuel is considered to be an effective measure to improve the urban air quality. Concerned over deteriorating air quality in Delhi, the Delhi government initiated different measures including stringent emission norms, improved fuel quality and above all introduction of cleaner fuel-CNG in public transport system. The entire city bus fleet was converted to CNG mode by 2002. The present study reports the comparative assessment of the status of air quality with respect to PM(10) and PAH before and after the introduction of CNG in public transport system in Delhi. The study has been carried out for two different time periods: first in the year 1998 and second in the year 2004. Following the total conversion of public transport system to CNG in 2002, Post-CNG data indicate a sharp reduction of 51-74% in the PM(10) concentration and 58-68% in the TPAH concentration as compared to the Pre-CNG data.  相似文献   

16.
The World Health Organization has estimated that air pollution is responsible for 1.4 % of all deaths and 0.8 % of disability-adjusted life years. NOIDA, located at the National Capital Region, India, was declared as one of the critically air-polluted areas by the Central Pollution Control Board of the Government of India. Studies on the relationship of reduction in lung functions of residents living in areas with higher concentrations of particulate matter (PM) in ambient air were inconclusive since the subjects of most of the studies are hospital admission cases. Very few studies, including one from India, have shown the relationship of PM concentration and its effects of lung functions in the same location. Hence, a cross-sectional study was undertaken to study the effect of particulate matter concentration in ambient air on the lung functions of residents living in a critically air-polluted area in India. PM concentrations in ambient air (PM1, PM2.5) were monitored at residential locations and identified locations with higher (NOIDA) and lower concentrations (Gurgaon). Lung function tests (FEV1, PEFR) were conducted using a spirometer in 757 residents. Both air monitoring and lung function tests were conducted on the same day. Significant negative linear relationship exists between higher concentrations of PM1 with reduced FEV1 and increased concentrations of PM2.5 with reduced PEFR and FEV1. The study shows that reductions in lung functions (PEFR and FEV1) can be attributed to higher particulate matter concentrations in ambient air. Decline in airflow obstruction in subjects exposed to high PM concentrations can be attributed to the fibrogenic response and associated airway wall remodeling. The study suggests the intervention of policy makers and stake holders to take necessary steps to reduce the emissions of PM concentrations, especially PM1, PM2.5, which can lead to serious respiratory health concerns in residents.  相似文献   

17.
多元配合物胶束增溶光度法测定微量氰化物   总被引:2,自引:0,他引:2  
根据CN-对丁二酮肟-Ni-OP-10体系的增色作用,建立了一种测定微量氰化物的新方法.该方法操作简便,选择性好,不需要蒸馏和萃取.CN-量在0~5μg/25ml内符合比尔定律,用于环境水中氰化物的测定,结果满意.  相似文献   

18.
The trace element contents of seven kinds of herbal plants and spice samples retailed in local markets in Kayseri-Turkey were determined by flame atomic absorption spectrometry after digestion with HNO3/H2O2 mixture. The concentration ranges for the studied elements were found as 6.0–15.2, 0–32.2, 80.0–324.8, 8.1–386.3, and 13.1–36.2 μg/g for copper, nickel, iron, manganese, and zinc, respectively. The levels of cobalt, lead, and chromium ions in all the investigated samples were found to be below the detection limit of flame atomic absorption spectrometry. The results found in the present work were compared with values in the literature.  相似文献   

19.
海河下游水体中DO与NH_3-N、COD_(Mn)相关关系探讨   总被引:2,自引:0,他引:2  
本文应用近年来海河下游监测数据对DO与NH3N和CODMn进行一元线性回归,得到两回归方程:NH3N=-128DO+1054;CODMn=-113DO+1692。并经相关系数和回归系数显著性检验,表明在999%的置信水平下DO与NH3N和CODMn线性相关均极其显著  相似文献   

20.
提出了在线富集-FAAS法中样品空白值测定的方法,讨论了不正确的样品空白值对测定结果准确度的影响.  相似文献   

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