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101.
辽河流域浑河沈阳段地表水重点控制有机污染物的筛选   总被引:6,自引:2,他引:6  
采用美国环保局工业环境实验室提出的化学物质的“潜在危害指数法”,对辽河流域浑河沈阳段地表水和底质中检出的有机污染物的潜在危害进行了排序,参考国内外有毒化学品优先控制名单的筛选原则和方法,结合本流域的实际情况,制定出重点控制有机污染物的评分标准,提出辽河流域浑河沈阳段重点控制有机污染物名单。考虑到个别有机污染物在水中的浓度很低,但在底质中相对含量较高,所以将底质的检测结果也纳入评分标准。  相似文献   
102.
Butter (45) and ghee (55) samples were collected from rural and urban areas of cotton growing belt of Haryana and analysed for detecting the residues of organochlorine, synthetic pyrethroid and organophosphate insecticides. The estimation was carried out by using multi residue analytical technique employing GC-ECD and GC-NPD systems equipped with capillary columns. Butter samples were comparatively more contaminated (97%) than ghee (94%), showing more contamination with organochlorine insecticides from urban samples. About 11% samples of butter showed endosulfan residues above MRL value and 2% samples had residues of synthetic pyrethroids and organophosphates each above their respective MRL values. In ghee, residues of HCH & DDT both and of endosulfan exceeded the MRL values in 5 and 20% samples, respectively. Among organophosphates, only chlorpyriphos was detected with 9% samples showing its residue above MRL value. Irrespective of contamination levels, residues above the MRL values were more in ghee. More extensive study covering other agricultural regions/zones of Haryana has been suggested to know the overall scenario of contamination of milk products.  相似文献   
103.
Atmospheric aerosols are an important contributing factor to turbidity in urban areas besides having impact on health. Aerosol characteristics show a high degree of variability in space and time as anthropogenic share of total aerosol loading is quite substantial and is essential to monitor the aerosol features over long time scales. In the present study extensive observations of columnar aerosol optical depth (AOD), total columnar ozone (TCO) and precipitable water content (PWC) have been carried over a tropical urban city of Hyderabad, India. Significant variations of AOD have been observed during course of the day with low values of AOD during morning and evening hours and high values during afternoon hours. Spectral variation of AOD exhibits high AOD at smaller wavelengths and vice versa except a slight enhancement in AOD at 500 nm. Anomalies in AOD, particulate matter and black carbon concentrations have been observed during May, 2003. Back trajectory analysis of air mass during these episodes suggested variation in air mass trajectories. Analysis of the results suggests that air trajectories from land region north of study area cause high loading of atmospheric aerosols. The results are discussed in the paper.  相似文献   
104.
Air pollution in the workplace environment due to industrial operation have been found to cause serious occupational health hazard. Similarly, heat stress is still most neglected occupational hazard in the tropical and subtropical countries like India. The hot climate augments the heat exposure close to sources like furnaces. In this study an attempt is made to assess air pollution and heat exposure levels to workers in the workplace environment in glass manufacturing unit located in the State of Gujarat, India. Samples for workplace air quality were collected for SPM, SO2, NO2 and CO2 at eight locations. Results of workplace air quality showed 8-hourly average concentrations of SPM: 165–9118 μg/m3, SO2: 6–9 μg/m3 and NO2: 5–42 μg/m3, which were below the threshold limit values of workplace environment. The level of CO2 in workplace air of the plant was found to be in the range 827–2886 μg/m3, which was below TLV but much higher than the normal concentration for CO2 in the air (585 mg/m3). Indoor heat exposure was studied near the furnace and at various locations in an industrial complex for glass manufacturing. The heat exposure parameters including the air temperature, the wet bulb temperature, and the globe parameters were measured. The Wet Bulb Globe Temperature (WBGT), an indicator of heat, exceeded ACGIH TLVs limits most of the time at all the locations in workplace areas. The recommended duration of work and rest have also been estimated.  相似文献   
105.
固定化微生物处理有机污染物的研究进展   总被引:4,自引:0,他引:4  
胡燕荣  于雪峰 《干旱环境监测》2002,16(4):195-196,F004
综述了近年来固定化微生物技术用于有机污染物治理中的最新进展,这些有机污染物包括难降解有机污染物(酚类、芳香烃类等)及其它化合物(DMP、甲硫醇恶臭气体、制药废水等)。此外,对藻类固定化技术作了简介,并对固定化技术的应用前景及存在问题进行了评述。  相似文献   
106.
垃圾填埋场渗出液中有害成分的研究   总被引:9,自引:0,他引:9  
研究垃圾填埋场渗出液中的有害成分。渗出液样品用适当的方法处理后 ,用气相色谱 -质谱联用方法和原子发射光谱法进行定性分析。然后用原子吸收分光光度法和反相高效液相色谱法定量测定样品中微量的 Cu、Zn、Pb、Cr、Cd、Hg、苯酚、对甲苯酚、萘、蒽  相似文献   
107.
对铜的 3条谱线 (2 49.2 nm、2 61 .4nm,3 2 4.8nm ) ,铅的 2条谱线 (2 83 .3 nm、2 1 7.0 1 nm )以及锌的 2条谱线(3 0 7.6nm、2 1 3 .9nm ) ,共 7条谱线的灵敏度、检测限、线性范围进行了归纳性总结 ,并对多种共存元素可能存在的干扰情况进行了研究 ,认为利用元素不同分析谱线的分析灵敏度差异 ,根据被测元素在样品消解液中含量 ,选择合适的谱线进行分析 ,既降低工作强度 ,又能获得满意结果  相似文献   
108.
活性炭法测量室内空气中氡浓度的影响因素研究   总被引:1,自引:0,他引:1  
探讨了各种因素对活性炭法测量室内空气中氡浓度的影响,并提出既能保证检测质量,又能符合工程检测需要、提高检测效率的检测条件范围。  相似文献   
109.
Kimpo metropolitan landfill has received various kinds of wastessince January 1992. The leachate level was measured to be 10.3 m in May 1995 and the level increased to 12.2 m in August 1996. Therefore, to prove the reason for the increasing leachate level, we calibrated hydraulic conductivity of each waste andintermediate layer using the HELP (Hydrologic Evaluation ofLandfill Performance) model. The leachate generation data measured from February 1993 to October 1995 was used in the model calibration. As a result of a model calibration, we obtained anaverage infiltration ratio and used this in analysis of the total water balance to predict elevation of leachate level. Main causes of the elevation of the leachate level were the high water content of the waste and the degradation of the leachate-drainage system caused by the subsidence of a naturalbarrier layer.  相似文献   
110.
Market samples (60) of six seasonal vegetables were monitoredduring 1996–1997 to determine the magnitude of pesticidalcontamination. The estimation of insecticide residuesrepresenting four major chemical groups i.e. organochlorine,organophosphorous, synthetic pyrethroid and carbamate, was doneby adopting a multiresidue analytical technique employingGC-ECD and GC-NPD systems with capillary columns. The testedsamples showed 100% contamination with low but measurableamounts of residues. Among the four chemical groups, theorganophosphates were dominant followed by organochlorines,synthetic pyrethroids and carbamates. About 23% of the samplesshowed contamination with organophosphorous compounds abovetheir respective MRL values. More extensive studies coveringdifferent regions of Haryana state are suggested to get a clearidea of the magnitude of vegetable contamination with pesticideresidues.  相似文献   
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