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1.
为了找到含砷试样保存的最佳条件,我们设计了不同试样、不同浓度、不同酸度、不同温度以及不同容器等条件的贮存方案,对24种含砷试样进行了近半年的试验研究,在此基础上,又对室温保存的含酸试样等做了大约贮存一年的稳定性考察。此研究不仅对研究方法和准确精密的测定是必要的,而且为大量样品的监测和大规模实验室质量控制的研究,提供了必要的依据。  相似文献   

2.
本实验选择有代表性的长江,东湖,汉江水作为研究对象,采用正交设计法对铜、铅、锌、镉、砷、汞等六种元素在不同固定剂、容器、温度下保存5个月浓度的变化作了系统研究,提出了实际水样的测定时限及最佳保存条件。根据上述三种原水样的不同过滤方式和48小时沉降试验,推荐了各类型水样的不同过滤方式和取样方式。  相似文献   

3.
本文论述了在采集水样时,可能引起水样变化,不能反映水体真实情况,失去其代表性的各种影响因素。综述了贮存容器材质的影响,水样的过滤方式,及测定Hg、Cr、As和重金属水样的保存条件和允许保存的时间。  相似文献   

4.
玻璃容器材质中一般含有少量金属元素。使用玻璃容器保存微量金属元素水样时就可能会污染水样,文中以铅元素为例,针对硬质玻璃容器用2种不同的清洗方法对保存水样的影响情况进行实验对比。  相似文献   

5.
本文研究了水中痕量铍的稳定性大小,与水中酸度、与水中存在的沉淀物种类及量以及与贮存容器有关,为了使标准溶液与水样中痕量铍不致因容器表壁吸附或沉淀物吸附而损失,经试验采用聚乙烯瓶盛装最好,并用盐酸或硝酸调至溶液酸度为pH1-2为好。  相似文献   

6.
环境样品中砷的形态分析   总被引:3,自引:0,他引:3       下载免费PDF全文
从砷的提取、不同形态砷的色谱分离和检测技术等3个方面综述了环境样品中砷的形态分析研究进展,指出发展简便、快速的分离富集技术及高灵敏性、高选择性的检测方法是今后的研究重点。  相似文献   

7.
不同形态的砷性质不同,毒性相差很大。砷的形态分析和形态研究十分活跃。现仅就近年来水环境中砷的形态分析的进展,作一简要介绍。 水中砷的形态有:砷酸、亚砷酸、甲基砷酸(MAA)、二甲基砷酸(DMAA)及它们的盐,三甲基砷及其氧化物。这些低含量共存形态的分析是先分离富集然后用各种方法测定,常用硼氢化钠(钾、锂)等还原剂将各种砷化物还原成相应形态的砷氢化物(胂,一、二和三甲基胂)进行分离,只有  相似文献   

8.
水中微量汞的稳定剂的研究   总被引:1,自引:0,他引:1  
选用不同类型稳定剂,分别于酸和碱性介质中用冷原子吸收法测定,以5种水样对照找出比较好的新型稳定剂,其稳定时间、贮存效果和适用性等方面具有很好的优点,避免了对人体、环境的二次污染,是目前微量汞较理想的贮存稳定剂.  相似文献   

9.
氢化物发生-原子荧光光度法测定水中砷和汞的比对   总被引:1,自引:0,他引:1  
通过水样中砷和汞测定的比对实验,研究了氢化物发生-原子荧光光度法测定砷和汞的优越性,并分别对方法检出限、精密度和准确度进行了测定,结果满意。  相似文献   

10.
比较了国产与进口HPLC-ICP-MS联用仪器在环境水样砷形态分析中的应用。国产和进口HPLC-ICP-MS联用仪器均能实现亚砷酸盐、二甲基砷、一甲基砷和砷酸盐的同时测定。国产仪器出峰时间较快,优于进口仪器。但是进口仪器上亚砷酸盐和二甲基砷的分离度优于国产仪器。国产仪器和进口仪器分析亚砷酸盐、二甲基砷、一甲基砷和砷酸盐,标准曲线的线性相关系数均大于0.995。国产仪器分析4种形态砷检出限范围为0.29~0.59μg/L,进口仪器分析4种形态砷检出限范围为0.24~0.36μg/L,没有数量级上的差异。国产仪器相对标准偏差范围为1.8%~9.0%,进口仪器相对标准偏差范围为0.8%~8.9%。精密度方面国产仪器和进口仪器水平相当。实际样品加标实验,国产仪器回收率范围为86.2%~112%,进口仪器回收率范围为96.4%~114%;使用进口仪器和国产仪器测定4种形态砷的有证标准物质,测定结果无显著性差异。国产HPLC-ICP-MS联用仪器可以满足砷形态检测分析的要求。对2款仪器的比较研究,为广大企事业单位及科研院所在选择HPLC-ICP-MS联用仪器时提供有价值的基础数据和参考建议。  相似文献   

11.
高灵敏XRF测定废水中痕量砷   总被引:2,自引:0,他引:2  
本文提出了在硫酸介质中,以锌粒还原产生氢化物,溴化铜溶液吸收,微孔滤膜过滤制成薄样,X射线荧光测定水中痕量砷的分析方法。  相似文献   

12.
Groundwater is the primary source of drinking water for more than 95% of the population in Punjab. The world health organization and US Environment Protection Agency recently established a new maximum contaminant level of 10 ppb for arsenic in drinking water. The arsenic concentration of deep water tube wells located in Amritsar city used for domestic supply for urban population ranged from 3.8 to 19.1 ppb with mean value of 9.8 ppb. Arsenic content in hand pump water varied from 9 to 85 ppb with a mean value of 29.5 ppb. According to the safe limit of As, 54% and 97%, water samples collected from deep water tube wells and hand pumps, respectively, were not fit for human consumption. Arsenic content in canal water varied from 0.3 to 8.8 ppb with a mean value of 2.89 ppb. Canal water has got higher oxidation potential followed by deep tube well and hand pump water. The present study suggests the regular monitoring of arsenic content in deep tube well and shallow hand pump waters by water testing laboratories. The consumption of water having elevated concentration of As above the safe limit must be discouraged. In south-western districts of Punjab, it recommends the use of canal water for drinking purposes and domestic use by rural and urban populations than ground water sources.  相似文献   

13.
报道了水和废水环境监测所用水质二硝基甲苯环境标准样品的研制情况。其中对水质二硝基甲苯环境标准样品的作用、样品的制备、均匀性测定、稳定性考察以及定值分析等方面做了较详细的介绍。  相似文献   

14.
污水库自净与运行情况调查及分析   总被引:1,自引:0,他引:1  
为了了解独山子石化总厂贮存式氧化塘型污水库使用多年的实际情况,统计,分析了近二年的水质监测数据及水生态情况,结果表明,污水库自净及运行状态良好,近期发生的生态环境被破坏事件主要是由于库区水面降低,底质毒物富集造成,控制生产排污,加强库区运行管理对污水库的水源保护极为重要。  相似文献   

15.
双道氢化物原子荧光法测定水和土壤中的砷   总被引:5,自引:0,他引:5  
用AFS-2201双道氢化物发生原子荧光法测定水、土壤样品中的砷含量,方法简捷、快速、准确,二次污染物少.HNO3浓度大于5ppm时,对测量结果有影响.主机通过与微机相联可直接得出监测数据,大大减轻了监测人员的工作量,测定结果令人满意.  相似文献   

16.
对青岛市某饮用水源地饮用水的钼、铍、硼、锑、钡、钒、钛、铊、砷、镉、铅、汞、镍、铜、锌共15种重金属元素进行了分析,并应用美国环保局推荐的健康风险评价模型对其所引起的健康风险作了初步评价。结果表明,通过饮水途径所致健康风险中,由致癌物砷所致的健康风险为8.15E-6 a-1,低于国际辐射防护委员会ICRP推荐的最大可接受风险水平5.0×10-5a-1;由非致癌物所致的健康风险中砷最大,铜和硼次之,二者的风险水平为10-9a-1和10-10a-1,均低于ICRP推荐的最大可接受风险水平。  相似文献   

17.
Previous work has shown that arsenic can accumulate in drinking water distribution system (DWDS) solids (Lytle et~al., 2004) when arsenic is present in the water. The release of arsenic back into the water through particulate transport and/or chemical release (e.g. desorption, dissolution) could result in elevated arsenic levels at the consumers' tap. The primary objective of this work was to examine the impact of pH and orthophosphate on the chemical release (i.e. desorption) of arsenic from nine DWDS solids collected from utilities located in the Midwest. Arsenic release comparisons were based on the examination of arsenic and other water quality parameters in leach water after contact with the solids over the course of 168~hours. Results showed that arsenic was released from solids and suggested that arsenic release was a result of desorption rather than dissolution. Arsenic release generally increased with increasing initial arsenic concentration in the solid and increasing pH levels (in the test range of 7 to 9). Finally, orthophosphate (3 and 5 mg PO4/L) increased arsenic release at all pH values examined. Based on the study results, utilities with measurable levels of arsenic present in their water should be aware that some water quality changes can cause arsenic release in the DWDS potentially resulting in elevated levels at the consumer's tap.  相似文献   

18.
Load duration curves were developed using the Hydrological Simulation Program FORTRAN (HSPF) for dissolved oxygen (DO) for the Amite River in Louisiana, USA. The concept of ‘dissolved oxygen reserve’, defined as the total quantity of DO, is introduced. The effect of temporal resolution on duration curves of DO reserve was examined using duration curves developed based on daily, weekly, biweekly, and monthly average data. Duration curves for DO exhibited high variability in the load estimated using daily data as compared to those based on biweekly and monthly data. A seasonal analysis revealed the trend in the DO reserve. The daily DO reserve for the Amite River at Port Vincent was 44,049.31 kg when daily summer data were used and 74,255.15 kg for daily annual data. A surplus of 10,691 kg of DO reserve was shown in the monthly data during critical summer months. The coefficient of variation (CV), used to define the temporal scale-induced uncertainty, was found to be linearly and inversely correlated with the logarithm of the time scale. Regression equations were developed to extrapolate near real-time flow and water quality data, greatly simplifying flow and water quality monitoring and reducing the cost involved in flow and water quality monitoring.  相似文献   

19.
本文讨论了质控混合水样的配制方法,叙述了质控样品的均匀性、稳定性试验及定值的原则和方法,详实地列出了有关统计检验方法。在现有实验室条件下,可以配制出满足监测工作需要的质量控制样品。  相似文献   

20.
采用离子交换和溶剂萃取相结合的分离;富集技术,事等离子体发射光谱仪(ICP-AES)测定,对昆明滇池7个取样点的砷形态进行了分离和必滇池环境对池中砷形态的迁移转化进行了探讨,为滇池砷污染的研究和治理提供了一定依据。  相似文献   

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