洹河水中痕量有机污染物的研究

采用固相萃取技术 ,对洹河水中痕量有机物进行富集 ,大量的地表水被 C1 8键合相萃取后 ,洗脱液经干燥浓缩用于 GC和 GC/MS分析 ,鉴定出 64种有机物 ,并对苯系物、杂环类等 2 7种主要污染物作了定量测定 ,得出有机物的沿途变化规律。     

水中汞监测存在的问题与解决办法

利用中日合作 (JICA)项目资金 ,对测定地表水中汞存在的主要问题 ,如水样的保存和处理 ,水样的消解 ,测汞的冷原子吸收法和原子荧光法等进行了研究。通过对 33个环境监测站的样品考核 ,发现测定结果与标准值相比 ,偏高的数据达 75 %以上。提出了用 1%H2 SO4 和 0 1%K2 Cr2 O7保存水样最好 ;高锰酸钾 -过硫酸钾消解法适用于消解含有机物、悬浮物和组成复杂的废水样 ,高锰酸钾 -硫酸消解法适用于消解被有机物轻度污染的废水 ,溴酸钾 -溴化钾消解法适用于消解地表水和含较少有机物的生活污水及工业废水。研究表明 :尤以硫酸 -高锰酸钾 -过硫酸钾消解体系消解地表水和废水效果良好。对冷原子吸收法和原子荧光法中影响汞测定的因素 ,如空白值高、干扰物的消除、载气种类和流量、反应瓶体积和气液比以及反应时间等提出了详尽的解决方法     

中国沿海三省主要饮用水源有机物监测

采用固相萃取、吹扫捕集和气相色谱-质谱联用仪(GC-MS)对江苏、浙江、山东省的21个主要地表饮用水源、126份水样中的25种VOCs、38种SVOCs进行定量检测。结果有19种VOCs、10种SVOCs至少在一个水源地多次被检出,其中挥发性氯代烃、苯系物、氯代苯类、酚类、硝基苯类、酞酸酯类、农药为中国或美国环境保护局提出的"水中优先控制污染物",最高检出量为27.79μg/L。三省主要地表水受到有机物轻度污染,水体中VOCs、SVOCs含量尚未超过《地表水环境质量标准》(GB 3838-2002)和《生活饮用水卫生标准》(GB 5749-2006)限值,工业废水排放及农田雨水径流是地表水有机物的重要来源。     

吹扫捕集-气相色谱/质谱联用法测定地表水中氯丁二烯

采用吹扫捕集-气相色谱/质谱联用法测定地表水中氯丁二烯。当进样体积为20 mL时,方法在0.100μg/L~50.0μg/L范围内线性良好,检出限为0.05μg/L,标准溶液平行测定的RSD≤3.7%,地表水样加标回收率为91.0%~101%,方法可用于地表水中卤代烃、苯系物等其他21种挥发性有机物的同时测定。     

气相色谱质谱联用技术在饮用水源地挥发性有机物特定项目中的应用研究

地表水环境质量标准(GB 3838-2002)中规定的集中式生活饮用水地表水源地特定项目中有20多项属于挥发性有机污染物,研究了吹扫捕集气相色谱质谱方法测定这些挥发性有机物特定项目.优化了色谱条件,测定结果线性良好,目标化合物加标回收率、检出限等指标均符合地表水环境质量标准的要求.     

地表水中半挥发性有机物的固相萃取GC-MS方法研究

利用膜式固相萃取与气相色谱-质谱联用,尽可能多的涵盖了GB 3838—2002饮用地表水80项分析中各种不同性质的半挥发性有机物,建立了地表水中半挥发性有机物的检测方法。优化的固相萃取条件:选用8270专用盘,在中性条件(pH 6～7)下,二氯甲烷淋洗2次,丙酮淋洗1次。方法检出限为0.02～0.17μg/L,各物质回收率均在EPA8270方法中所推荐的回收率范围内。     

吹扫捕集装置在测定地表水中挥发性有机物的最佳测试条件

吹扫捕集法自1974年提出以来被广泛的用于地表水、地下水、饮用水和废水中挥发性、半挥发性有机物的检测。吹扫捕集／气相色谱联机有很好的方法检测限,可以检测出浓度为0．1μg／L的挥发性有机物,但水样中这类有机物的含量通常是痕量级别,要做到准确测量,需要仪器检测时的条件处于最佳,现对吹扫捕集装置的性能、吹扫时间、解吸时间和解吸温度等条件进行选择。     

地表水中TOC与COD换算关系研究

总有机碳(TOC)相对于化学需氧量(COD) 能够更全面地反映水体中有机物的污染程度,且TOC测定仪操作简单,数据准确。通过18个地表水水质自动监测站对水中有机污染物的COD与TOC监测数据的相关性研究,建立了TOC与COD之间的线性回归方程,为地表水的TOC监测代替COD监测提供了数据支持。     

SPME-GC同时测定地表水环境质量标准特定项目中硝基苯类和氯苯类化合物

针对地表水特定项目有机物中硝基苯类和氯苯类的测定,采用固相微萃取(SPME)前处理技术,用毛细管色谱柱进行色谱分离,用ECD检测器进行测定。SPME富集效率达118~1352倍,检出限为0.00004~0.05μg/L,方法的线性相关系数为0.9963~0.9999,RSD为2.0%~11.0%,加标回收率为87.0%~108%,所有技术参数均可满足地表水环境质量标准。该方法简单、快捷、无污染且省时省力,具有较好的推广性。     

用一次新蒸馏水代替重蒸馏水测定高锰酸盐指数的可行性研究

用一次新蒸馏水代替重蒸馏水测定高锰酸盐指数的可行性研究金中华（江苏省灌云县环境监测站２２２２００）《水和废水监测分析方法》（以下简称《方法》）规定用高锰酸钾法测定地表水中高锰酸盐指数，所有试剂均用不含有机物及还原性物质的重蒸馏水配制，即在一次蒸馏水中...     

高氯低COD值水样的无汞快速测定法

以硝酸银和硫酸铬钾代替硫酸汞来消除 COD 测定中的氯离子干扰，同时将重铬酸钾溶液的浓度降低为0.100 mol／L，并用硫磷混酸代替硫酸，该方法经过对标准样品和实际样品的测定，表现出对于测定氯离子含量低于25000 mg／L的高氯低 COD 值水样具有较好的准确度和精密度，同时可以实现银盐的回收再利用。     

Desorption of arsenic from drinking water distribution system solids

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.     

Assessment of domestic water quality: case study, Beirut, Lebanon

In urban cities, the environmental services are the responsibility of the public sector, where piped water supply is the norm for urban household. Likewise, in Beirut City (capital of Lebanon) official water authorities are the main supplier of domestic water through a network of piping system that leaks in many areas. Beirut City and its suburbs are overpopulated since it is the residence of 1/3 of the Lebanese citizens. Thus, Beirut suffers deficiency in meeting its water demand. Water rationing, as a remedial action, is firmly established since four decades by the Lebanese Water Authorities. Consumers resorted then to private wells to supplement their domestic water needs. Consequently, household water quality is influenced by external factors relating to well water characteristics and internal factors depending on the types of the pipes of the distribution network and cross connections to sewer pipes. These factors could result in chemical and microbial contamination of drinking water. The objective of this study is to investigate domestic water quality variation in Beirut City emerging form the aforementioned factors. The presented work encircles a typical case study of Beirut City (Ras Beirut). Results showed deterioration pattern in domestic water quality. The predicted metal species and scales within the water pipes of distribution network depended on water pH, hardness, sulfate, chloride, and iron. The corrosion of iron pipes mainly depended on Mg hardness.     

全自动甲基汞分析仪测定水和废水中甲基汞

建立了全自动甲基汞分析仪测定水和废水中甲基汞的方法,对较清洁的地表水和一般废水样品可直接衍生化测定,对基体复杂水样则需蒸馏后再衍生化测定。该法在水样中甲基汞含量为0~1 000 pg范围内线性良好,相关系数r为0.999 7,检出限为0.002 ng/L,标准参考物质测定结果均在参考值范围内,相对标准偏差为1.1%,加标回收率为83.2%~96.6%。该法适用于水及废水中甲基汞的检测。     

《地表水和污水监测技术规范》(HJ/T 91-2002)的相关技术说明

文章从概念名称、采样方式、样品保存、质量管理等多方面阐述了《地表水和污水监测技术规范》(HJT91-2002)的相关技术,对于贯彻执行该规范具有很强的指导性和操作性。     

离子色谱法测定地表水和饮用水中亚氯酸盐、溴酸盐和氯酸盐

采用KOH梯度淋洗离子色谱法测定地表水和饮用水中ClO2-、BrO3-和ClO3-，在试验确定的条件下，3种离子与F-、Cl-、NO2-、NO3-、SO2-4、Br-、I-等7种离子分离度良好。 ClO2-、BrO3-、ClO3-在50．0μg/L～1000μg/L范围内线性良好，检出限分别为5．2μg/L、8．9μg/L、7．6μg/L，环境水样加标平行测定的RSD分别为2．1％～5．4％、4．1％～5．4％、2．5％～4．8％，两个质量浓度水平加标的平均回收率分别为93．7％～96．5％、90．3％～94．8％、98．7％～111％。     

Measuring Water Storage Fluctuations in Lake Dongting, China, by Topex/Poseidon Satellite Altimetry

Although satellite radar altimetry was developed and optimized for open oceans, it has been used to monitor variations in the level of inland water-bodies such as lakes and rivers. Here, for the first time, we have further used the altimetry-derived variation of water level for estimating the fluctuation of water storage as an addition to the present in situ water storage estimation systems to be used in remote areas and in emergency situation such as in the events flooding monitoring and for studying the effect of climate change. Lake Dongting, the second largest lake in China, influenced frequently by flooding, was, therefore, chosen to demonstrate the potential of the technique. By using the concept of an “assumed reference point”, we converted Topex/Poseidon satellite altimetry data on water level variations in Lake Dongting to “water level” data. The “water level” time-series data and in situ water storage were used to establish a rating curve. From the rating curve, we converted data on “water level” derived from seven years (1993–1999) of Topex/Poseidon data to actual water storage in Lake Dongting. The result reveals that the seasonal and annual fluctuations of water storage occurred during the 1990s with a more frequent flooding at the late 1990s' especially the flooding in whole catchment level in 1998 and 1999. The study supports the usefulness of satellite altimetry for dense and continuous monitoring of the temporal variations in water dynamic in moderate to large lakes.     

亚甲蓝分光光度法测定饮用水中阴离子表面活性剂的方法讨论

用10ml氯仿萃取离子缔合物一次,洗涤一次,不稀释。它与国标方法的线性回归无显著性差异,此方案测定样品的准确度En为0·34,小于1,结果令人满意,测量不确定度是除国标方法外最低的方案。因此它具有低污染、操作简单的特点,并可用于常规检测饮用水中的LAS。     

Hydrological influences on the water quality trends in Tamiraparani Basin,South India

Water quality variables – Turbidity, pH, Electrical Conductivity(EC), Chlorides and Total Hardness (TH) were monitored at adownstream location in the Tamiraparani River during 1978–1992. The observations were made at weekly intervals in a watertreatment and supply plant using standard methods. Graphical andstatistical analyses were used for data exploration, trenddetection and assessment. Box-Whisker plots of annual andseasonal changes in variables indicated apparent trends beingpresent in the data and their response to the seasonal influenceof the monsoon rainfall. Further, the examination of the medianvalues of the variables indicated that changes in the directionof trend occurred during 1985–1986, especially in pH, EC and TH. The statistical analyses were done using non-parametric methods,the ANCOVA on rank transformed data and the Seasonal Man-Kendalltest. The presence of monotonic trend in all the water qualityvariables was confirmed, however, with independent direction ofchange. The trend line was fitted by the method of leastsquares. The estimated values indicated significant increases inEC (28 S cm^-1) while significant decreases were observed inturbidity (90 NTU), pH (0.78), and total hardness (23 ppm) in a span of 15 years. The changes induced in river flow by the addition of a stabilizing reservoir, the influence of seasonal and spatialpattern of monsoon rainfall across the river basin and the increased agriculture appear causative factors for the water quality trends seen in the Tamiraparani River system.