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111.
112.
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   
113.
基于颗粒物浓度的沙尘天气分级标准研究   总被引:11,自引:2,他引:11  
沙尘天气在近年对我国城市空气质量造成明显影响。目前我国沙尘天气分级仍然按照气象标准 ,主要是以水平能见度进行分级。文章参考国外的有关标准 ,通过统计近年来我国沙尘天气过程中的颗粒物浓度 ,结合我国沙尘天气的发生情况和特点 ,提出了基于沙尘浓度的沙尘天气分级标准  相似文献   
114.
研究了用固相萃取富集高效液相色谱法测定环境水样中痕量重金属镍、铜、银、铅、镉和汞的方法。环境水样中的镍、铜、银、铅、镉和汞用四 -(对二甲氨基苯基 ) -卟啉 (T4 -DMAPP)柱前衍生 ,用C18固相萃取小柱萃取富集镍、铜、银、铅、镉和汞的T4 -DMAPP络合物 ,富集倍数为 1 0 0倍 ,然后用甲醇和四氢呋喃梯度洗脱为流动相 ,WatersXter raTMRP18( 3 9mm× 1 5 0mm)色谱柱为固定相分离 ,用二极管矩阵检测器检测。镍、铜、银、铅、镉和汞的检测限分别为3、2、4、3、1 5ng/L和 3ng/L。方法相对标准偏差为 1 8%— 3 2 % ,标准回收率为 92 %— 1 0 7%。该方法用于测定环境水样中的痕量重金属 ,结果令人满意  相似文献   
115.
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   
116.
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   
117.
Biomonitoring dissolved heavy metals within estuaries,particularly at their upper reaches, frequently has to relyon several biomonitors; rarely a single species thrives allalong the salinity gradient. To properly do so, it must beestablished whether those biomonitors actually accumulateheavy metals alike. In this study, two brown seaweeds fromthe upper section of three NW Spain estuaries – the widely-known Fucus vesiculosus and the estuarine Fucusceranoides – were compared as metal biomonitors. Bothspecies were collected at five locations where they eithercoexist or live close to each other and their heavy metalcontent (Cu, Cr, Mn, Zn, Fe, Al) was measured. Analyseswere appropriately replicated for each species x locationcombination to allow a statistically reliable detection ofdifferences in bioaccumulation, with particular emphasis onthe magnitude of interspecific differences. The lack of significant differences for Cu, Mn, and Zncontents in F. ceranoides and F. vesiculosussupports the feasibility of their joint use to monitorthese metals along the estuaries. Conversely, F.ceranoides concentrated significantly higher levels of Cr,Fe, and Al than F. vesiculosus and hence combiningdata for both fucoids to monitor these elements seemsimpractical. The correlation of species differencestogether with a similar Al:Fe ratio in both weed tissue andsediment suggest that Cr, Fe, and Al tissue-burdens mightbe considerably biased by sediment retained on the surfaceof the weed. Parallel analyses of Al and/or Fe in seaweedsand sediments could serve to keep track of thisinterference and may help to combine data from both fucoidsfor monitoring elements like Cr.  相似文献   
118.
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   
119.
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   
120.
Cadmium and lead were determined in different tissues (muscle,gill, stomach, intestine, liver, vertebral column and scales) of Tilapia nilotica from the High Dam Lake, Aswan (Egypt) to assess the lake water pollution with those toxic metals. Fish samples were chosen from different ages and weights to be analyzed along with samples of the aquatic plant(Najas armeta), sediment and lake water.The results showed that cadmium and lead concentrations were higher in fish scales and vertebral column than in the other parts of the fish. Cadmium and lead levels in High Dam lake water and fish (Tilapia nilotica) were a result of the pollution which uptakes from aquatic plants, sediments andgasoline containing lead that leaks from fishery boats. Tilapia nilotica fish was used as a good bio-assay indicator for the lake pollution with cadmium and lead. The fish musclesin this study were in the safety baseline levels for man consumption.  相似文献   
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