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1.
重视废水监测分析预处理技术陶大钧,李易炜,袁心莹(无锡市环境科学研究所214033)任何样品、任何分析项目,都要根据所选用的分析方法进行不同的预处理。固体样品,要进行液化处理,生物样品要进行待测有机物质的分离或无机化处理,气体样品则先要进行采样浓缩,...  相似文献   

2.
上海市降尘监测中存在的问题   总被引:2,自引:2,他引:0  
降尘监测是探索大气可自然沉降颗粒物对环境影响的不可缺少的手段之一.降尘监测因其采样设备简便、操作简单易行等优点被广泛运用,但是监测周期长、环节多等因素都会影响降尘监测的准确性.通过对上海市降尘数据分析发现,上海市降尘监测中存在降尘数据波动大、受周边环境影响大、人为破坏多等问题,并就这些问题提出了若干建议和解决办法.  相似文献   

3.
挥发性有机物气体污染源监测中直接采样法的评价   总被引:3,自引:2,他引:1  
挥发性有机物气体污染源监测中 ,采样与样品的保存是极其关键的环节 ,文中评价了两种材质的塑料采样袋对样品保存的影响 ,并与玻璃针筒进行比较 ,讨论了塑料袋和玻璃针筒采样中导致样品浓度衰减的主要因素  相似文献   

4.
空气质量周报二氧化硫采样过程影响因素的探讨   总被引:1,自引:0,他引:1  
文章通过对空气质量周报连续采样过程有关影响因素进行探讨 ,分析了影响大气二氧化硫监测结果的一些原因或可能 ,首次对甲醛吸收液连续采样稳定性提出疑问 ,强调周报质量保证的重心要从实验室环节转到现场采样等环节上来  相似文献   

5.
介绍了国家重大科学仪器设备开发专项"基于质谱技术的全组分痕量重金属分析仪器开发和应用示范"项目在电感耦合等离子体质谱仪(ICP-MS)研发、低温等离子体样品引入ICP-MS联用系统、ICP-MS监测汞的采样与预处理等方面的研究进展,并对ICP-MS应用发展及产业化前景进行了展望。  相似文献   

6.
总磷是评价水质的一项重要指标,现对样品中悬浮物(泥沙)含量、加酸保存样品保存时间与调节pH值对总磷测定的影响进行研究。结果表明,随着沉降时间的延长总磷测定值逐渐降低,加酸保存的样品总磷测定值随保存时间的延长而增高,且测定时是否调回中性对测定结果基本无影响。故进行地表水中总磷的测定需严格按照标准规定的样品采样过程控制采样沉降时间,加酸保存,24 h以内进行测定,测定时无需调回中性。  相似文献   

7.
真空罐/气相色谱-质谱法是我国目前用于环境空气中挥发性有机物(VOCs)监测的主要方法。对该方法的采样前及采样环节的技术细节(包括流量控制器和过滤器的校准检查,采样罐的性能检查,样品的采集、运输及保存),以及实验室分析环节的技术细节(包括色谱柱的选择,内标物的选择,湿度及气体稀释仪对分析结果的影响,标准曲线绘制方式和系统性能优劣的判断)进行讨论和分析。并针对以上技术细节提出解决方案和注意事项,以期为分析人员提供技术参考。  相似文献   

8.
针对生活垃圾焚烧企业烟气排放烟囱6个断面单点采样的试验结果,分析按照《固定污染源排气中颗粒物测定与气态污染物采样方法》(GB/T 16157—1996)多断面点采样与单一固定断面点采样对监测结果的影响。试验表明,烟道气在不同断面点质量浓度分布差异较大,相对于样品实际监测值,各断面点二噁英毒性当量浓度最大正偏差达到+306%,最大负偏差达到-96%,测定的18个断面点样品,只有2个样品与实际样品监测值相近。  相似文献   

9.
环境空气中多环芳烃的监测研究进展   总被引:6,自引:0,他引:6  
介绍了国内外监测环境空气中多环芳烃 (PAHs)的进展情况。并就环境空气中PAHs的采样技术、样品预处理、分离分析方法 ,以及环境空气中PAHs的影响因素及源解析等方面进行了详尽的阐述  相似文献   

10.
我国将在一定时期内对大气环境中二氧化硫(SO_2)及氮氧化物(NO_x)污染监测采用三种不同监测方法共存的方针,即采用间断采样实验室分析法、24小时连续采样实验室分析法及连续自动监测法。由于这三种监测方法所采用的采样方法及分析方法各不相同,因此监测结果必然存在着不同程度的差异。监测结果的准确性、可靠性及代表性不仅依赖于分析方法,而且在很大程度上依赖于采样方法。而采样精度表示样品的代表性,它受污染物排放特征、扩散机理、采样频数、采样时段及置信水平等因素的影响。本文以大量实地监测数据依据,用统计分析的方法,对不同监测点所采用的不同监测方法的采样精度进行了比较。推荐一种估计采样精度的方法。  相似文献   

11.
Tube type samplers with two different adsorbents, Chromosorb 106 and Tenax TA, were evaluated by laboratory experiments and field tests for simultaneous diffusive sampling of alpha-pinene, beta-pinene and delta 3-carene and subsequent thermal desorption-gas chromatographic analysis. No statistically significant effects of exposure time, concentrations of monoterpenes or relative humidity were found for samplers with Chromosorb 106 when running a factorial design, with the exception of the adsorption of delta 3-carene, for which some weak effects were noted. Samplers with Tenax TA were affected by the sampling time as well as the concentration for all terpenes, with a strong interaction effect between these two factors. The terpenes showed good storage stability on both adsorbents. No effect of back-diffusion was noted when using Chromosorb 106, while Tenax TA showed some back-diffusion effects. The uptake rates, in ml min-1, for the terpenes on Chromosorb 106 were 0.36 for alpha-pinene, 0.36 for beta-pinene and 0.40 for delta 3-carene. The corresponding average values on Tenax TA were 0.30 for alpha-pinene, 0.32 for beta-pinene and 0.38 for delta 3-carene. The field validation proved that diffusive sampling on Chromosorb 106 agreed well with pumped sampling on charcoal for stationary samples, while the personal samples indicated a discrepancy of 25% between Chromosorb 106 and charcoal samples. Tenax TA generally gave lower results than Chromosorb 106 in all field samples. Samplers packed with Chromosorb 106 could be used to monitor terpene levels in workplaces such as sawmills. The major advantages with this method are the sampling procedure, which is simple to perform compared to other techniques, the easily automated analysis procedure and the possibility to reuse the samplers.  相似文献   

12.
北京市城市非点源污染特征的研究   总被引:18,自引:1,他引:18  
通过监测降雨径流水质,研究了北京市城市非点源污染的特征。结果表明,北京市城市地表径流水排入任何地表水体都会对其造成污染,且城市地表径流水的大部分水质指标已经达到了污水综合排放的三级标准,因此,我们对待城市地表径流水应该如对待污水一样处理。对于TN、TP、CODCr、BOD5浓度,路面径流要高于屋顶径流,而对于SS浓度,屋顶径流高于路面径流。总磷TP颗粒吸附态的污染物对总污染物的贡献最大,对于路面径流高达83.1%,对于屋顶径流为68.6%,其次是CODCr,总氮TN的颗粒吸附态的贡献较低。通过沉积或过滤去除城市地表径流中的悬浮颗粒物,可以提高城市地表径流的水质。所有污染物随降雨过程变化的总体趋势为雨水初期径流污染物浓度很高,随降雨历时的延长,污染物浓度逐渐下降并趋于稳定。初期径流危害较大。  相似文献   

13.
In the present study, the BCR (Community Bureau of Reference) sequential procedure has been applied to determine the zinc partition in sediments taken from a river situated in the Southwest of Romania, in a region subject of intense mining activities. The sampling was performed during three sampling expeditions, organized in the spring, summer, and autumn, 2007. The zinc concentration in different fractions was normalized, its concentration being related to the concentrations of some metals (such as Al or Fe) that are naturally present in sediments. The zinc-contaminated sediments from the investigated area have been evaluated by means of combining the analysis data from the BCR sequential extraction with the normalization to the Al content. The most important zinc collector in the samples taken during the three sampling expeditions is the easily soluble fraction, next being amorphous iron and manganese hydrated oxides fraction, followed by organic matter fraction.  相似文献   

14.
The increasing demand for environmental pollution control results in the development and use of new procedures for the determination of dangerous chemicals. Simple screening methods, which can be used directly in the field for a preliminary assessment of soil contamination, seem to be extremely advantageous. In our laboratory, we developed and optimized a rapid test for a preliminary evaluation of both the concentration and the mobility of some potentially toxic metals in soils. This screening test consists of a single extraction of the soil sample with a buffer solution, followed by the titration of the extracted solution with dithizone to determine the contents of bi-valent heavy metals (such as Pb, Cu, Zn, and Cd). This screening method was then directly applied in the field during the sampling campaign in the framework of an Italian–Serbian collaborative project, finalized in the study of metal availability in soils. The results obtained in the field with the rapid test were compared with those obtained in the laboratory following the conventional procedure commonly used to evaluate metal bioavailability (diethylenetriaminepentaacetic extraction). Moreover, selected samples were analyzed sequentially in the laboratory using the standardized BCR three-step sequential extraction procedure. The screening test gave results conceptually in good agreement with those obtained via the BCR procedure. These preliminary data show that the proposed screening test is a reliable method for the preliminary rapid evaluation of metal total concentrations and of potential metal mobility in soils, supporting sampling activities directly in the field.  相似文献   

15.
内陆水环境污染监测的多时相遥感信息模型   总被引:8,自引:0,他引:8  
介绍了遥感水质监测的基本原理,对遥感技术在水质监测领域的国内外发展现状进行了归纳分析,并论述了建立多时相、通用型内陆水环境污染遥感监测模型的可行性,最后以湘江长沙段为研究区域,创建了适用于DO、CODCr、CODMn、BOD和TN的水污染遥感因子和相应的多时相遥感信息模型。  相似文献   

16.
Areas of Concern such as the Niagara and Detroit Rivers contain a myriad of point and non-point sources. These are difficult and expensive to monitor and often present unique analytical problems and so are subject to analytical error. The Niagara River Toxics Committee (NRTC) and the Upper Great Lakes Connecting Channels Study Modeling Committee designed programs to indirectly monitor these sources by upstream/downstream sampling at the head and mouth of the rivers. These two studies are compared and the data analysis problems that were encountered are discussed. Upstream/downstream samples were paired to obtain differential loadings wherever possible, but when some results were reported as below the detection limit, a maximum likelihood estimate was used. The resulting differential loading, adjusted for non-point sources, is the total point source load to the river minus any losses due to volatilization, settling or degradation.  相似文献   

17.
深圳市饮用水源中CODMn与TOC的相关性研究   总被引:5,自引:0,他引:5  
通过对深圳市饮用水源中CODMn和TOC测定结果的相关性分析,结果表明,水库内监测点位及监测区域CODMn与TOC相关性良好,水库外监测点位及监测区域CODMn与TOC相关性不显著,而整个监测区域的CODMn与总有机碳相关性令人满意。因此,提出了TOC值可直接作为饮用水源在线监测有机污染物的综合评价指标,同时也实现了湿式氧化法测定TOC在地表水监测中的应用。  相似文献   

18.
Sampling can be the source of the greatest errors in the overall results of foliar analysis. This paper reviews the variability in heavy metal concentrations in tree crowns, which is a feature that should be known and understood when designing a suitable leaf sampling procedure. The leaf sampling procedures applied in 75 articles were examined. Most of the environmental studies used a closely related form of the UN/ECE-EC leaf sampling procedure, which was developed for the long-term monitoring of forest condition. Studies with objectives outside the UN/ECE-EC field of application should utilize a sampling procedure that is in accordance with the objectives of the study and based on the observed variation in pilot and similar studies. The inherent sources of heavy metal variability inside the stand, i.e. the crown class, stand management, site properties, crown dimensions, infections, seasons, etc. were discussed, but the underlying causes of this variability are rarely understood. The inherent variability in tree crowns is the reason for using leaf sampling as a tool in pollution studies. The objectives of a pollution study determine which sources of variability are utilized by the researcher.  相似文献   

19.
根据PM2.5中重金属监测国标分析方法,从PM2.5采样方法、采样保存条件、滤膜材质性能等方面说明利用空气自动采样滤膜监测PM2.5中铅和镉是可行的;对手工采样(石英滤膜)和Beta射线法自动采样(自动采样滤膜)2种方法,对PM2.5实际样品中铅和镉的结果进行比较,结果显示:自动采样滤膜的空白检出和检出限均满足铅和镉的监测需求,铅和镉的回收率分别为95.2%~107%和91.8%~105%,与手工采样方法相比测得铅和镉的相对误差分别为3.6%~8.4%和1.3%~10.8%,从实践角度进一步证明了利用自动采样滤膜对PM2.5中铅和镉进行监测是可行的。  相似文献   

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