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1.
本文对兰州市不同交通路口铅污染现场监测及交警人群健康体检,结果表明各路口受汽车尾气污染严重,铅浓度在1.16~2.64μg/m3之间。将120名交警分外勤警70人作为污染组,内勤警及户藉警50人作为对照组,调查结果尿中δ-氨基乙酰丙酸两组比较没有统计学差异(P>0.05);污染组发铅、尿铅浓度均显著高于对照组,发锌、铜、钙及血中IgA、IgG、IgM均低于对照组,并具有统计学差异(P<0.05,P<0.01)。提示街道空气铅污染对交警体内无机盐水平及机体免疫能力具有一定的影响。  相似文献   

2.
本文介绍了用毛细管柱气相色谱法定量测定给水中三卤甲烷(氯仿、一溴二氯甲烷、二溴一氯甲烷和溴仿)及四氯化碳的方法。其色谱条件是:检测器(ECD)温度:345℃;色谱柱:HP5(25m×032mm×105μm)柱;进样口温度:250℃。该方法的最小检出下限分别为:氯仿01μg/l、四氯化碳01μg/l、一溴二氯甲烷02μg/l、二溴一氯甲烷02μg/l和溴仿04μg/l。  相似文献   

3.
用大型溲运动及生存抑制试验和蚕豆根尖微核技术监测北京凉水河水质毒性,监测结果表明,凉水河6个采样点的河水对大型溲运动均有不同程度抑制作用和致死作用;河水的蚕豆根尖微核率也明显高于对照组(P〈0.01),揭示凉水河河水不仅具有一般的急性毒性,还存在一定程度的遗传毒性。  相似文献   

4.
钴 5-Cl-PADAB分光光度法天然水中钻含量很低,浓度多数为每升0.01-l卜g,对人、动植物不会产生毒害作用。有色金属冶炼厂和加工厂等企业的废水中常含高浓度的钻。水中钻的浓度为0.1-0.27mg/L时,对西红柿等植物产生毒害作用,硫酸钻浓度为...  相似文献   

5.
光离子化检测器便携式气相色谱仪快速测定水中苯系物   总被引:4,自引:0,他引:4  
本文研究了使用光离子化检测器便携式气相色谱仪,在环境温度下手工摇荡的快速顶空法测定水中苯系物(苯、甲苯、乙苯、邻、间、对位的二甲苯及异丙苯)的分析方法。方法的线性范围为0~180μg/L,相关系数均在0.996以上,方法的变异系数分别为1.0~14%(10μg/L),2.9~7.8%(30μg/L),方法的最低检测限达0.5~1.5μg/L。  相似文献   

6.
李吉文  邹文良 《干旱环境监测》1994,8(4):227-228,242
对乌鲁木齐地区5所医院1所卫生防疫站的医用诊断X射线机房内空气中正负离子浓度进行了调查,结果表明:透视和摄片机房空气中正负离子浓度分别为474±118,312±104(个/cm3)和404±101,256±78(个/cm3).单极系数(n+/n-)分别为1.52和1.58。正离子浓度均高于对照组(P<0.01),n+/n-相当于对照组的1,37和1.42倍。开机后空气中正离子浓度显著高于开机前浓度,n+/n-开机后相当于开机前的1.66和1.59倍,呈现出X线机房空气中正负离子严重失调。提示应加强有害因素的防护。  相似文献   

7.
高压蒸汽消化法测定废水化学需氧量的再研究   总被引:2,自引:0,他引:2  
用"自控式高压蒸汽消解器"作为高压蒸汽消化法测定废水化学需氧量的消化装置,详细研究了消化条件,最后确定,消化体系中(1/6)K2Cr2O7浓度为01mol/L,H2SO4浓度为10.1mol/L,催化剂Ag+浓度为0.03mol/L,消化温度为130℃,恒温时间为20min。用此方法和条件测定了12种单纯有机化合物和16种不同工业废水的化学需氧量,与标准回流法相比,相对误差在-5.5-6.0%之间。  相似文献   

8.
胡斌 《干旱环境监测》1996,10(3):172-173
对伊犁西部居民所接触的环境介质中氟含量和日摄氟总量进行调查,推出其饮水(茶)氟的适宜浓度为:饮水氟0.53mg/L,饮茶氟1.36mg/L,茶叶用量应控制在5.23g/日·人以下.  相似文献   

9.
锅炉烟尘排放浓度公式的化简及应用靳书月靳林萍(山西阳泉市环境监测站,阳泉045000)笔者对GB5468—91《锅炉烟尘测试方法》4.9.1烟尘排放浓度公式(18)进行简化并引进H(K)值(锅炉出力影响系数):C=g2-g1VtMT0+tsT0P0P...  相似文献   

10.
铝电解粉尘有机提取物及其组分对DNA修复合成的影响   总被引:2,自引:0,他引:2  
以外周血淋巴细胞程序外DNA合成(UDS)为观察指标,研究了铝电解粉尘及其5个组分对人外周血淋巴细胞UDS的影响。结果表明,在提取物浓度为19-75μg/ml范围内,粉尘有机提取物及其5个组分的细胞UDS值均有不同程度的增加,且存在明显的剂量--反庆关系,有机碱组分和脂肪烃组分与阴性对照组比较,有显著性差异(P〈0.05),而粉尘有机提取物及其有机酸组分、多环芳烃组分、极 合物组分与组性比较,有极  相似文献   

11.
通过对钒渣经碱浸和酸浸后V2O5回收率的比较,确定了应用H2SO4-氟化物浸出工艺可使渣中钒大部分转变为可溶性盐。分别采用H2SO4-NH4HF2及H2SO4-CaF2浸出工艺从湿冶钒渣中提取V2O5,前者较为满意,V2O5浸出率在65%以上,且氟化物可循环利用。  相似文献   

12.
何德文  张子冲 《干旱环境监测》1999,13(4):200-201,206
通过对库仑滴定法测定废水中化学需氧量存在的问题分析,提出相应解决办法,加强空白值式剂,器皿使用过程中的纯净;注重废水稀释倍数的影响。这些措施为快速CODcr值的可靠性提供了保证。  相似文献   

13.
Risk assessment of trihalomethanes from tap water in Fortaleza, Brazil   总被引:2,自引:0,他引:2  
The cancer risks (CR) by oral ingestion, dermal absorption, and inhalation exposure of trihalomethanes (THM) from tap water of ten districts in Fortaleza, Brazil were estimated. The mean levels of THM compounds were obtained in Fortaleza tap water as follow: 63.9 microg L(-1) for chloroform (CHCl(3)), 40.0 microg L(-1) for bromodichloromethane (CHBrCl(2)), and 15.6 microg L(-1) for dibromochloromethane (CHBr(2)Cl). Bromoform (CHBr(3)) was not detected. The mean CR for THMs in tap water is 3.96 x 10(-4). The results indicate that Fortaleza residents have a higher CR by inhalation than dermal absorption and oral ingestion. The CR for CHCl(3) contributes with 68% as compared with the total CR, followed by CHBrCl(2) (21%), and CHBr(2)Cl (11%). The hazard index (HI) is about ten times lower than unity, not indicating non-cancer effects.  相似文献   

14.
SO2气体对树木叶片叶绿素含量的影响   总被引:7,自引:0,他引:7  
丛者福 《干旱环境监测》2000,14(3):181-182,190
应用分光光度法研究乌鲁木齐市常见行道树种新疆扬、大叶白腊和新疆大叶榆受SO2气体危害后,树木叶片叶绿素(CA、CB、Cr)含量的动态变化,以了解其抗性特点。表明,名树种在受危害全进程中其表现不同,树木一身亦具有一定的自调节能力。同时叶绿素在各阶段相对含量的动态变化特点是衡量树种抗性大小的可供参考的有价值指标之一。  相似文献   

15.
聚四氟乙烯高压密封罐消解样品测定五氧化二钒   总被引:1,自引:1,他引:0  
利用聚四氟乙烯高压密封罐消解矿石样品测定五氧化二钒,具有操作手续相对简便、轻松、快捷等优点,与传统的硫酸-磷酸混合酸消解或采用碱熔融前处理法比较,相对误差小于1.6%,样品的添加标准回收率为92.9%~103.5%。  相似文献   

16.
研究了8-羟基喹啉与NO^-2-碘胺重氮盐偶联反应的条件及其产物的极谱行为。二阶导数波高与NO^-2的浓度在0.002-0.2mg/L内呈良好的线性关系,回收率为98%-103%,已用于环境水样中NO^-2的测定。  相似文献   

17.
浅谈TOC与CODCr的关系   总被引:10,自引:0,他引:10  
介绍了TOC和CODCr的含义,比较了TOC与CODCr测定方法、使用仪器的不同和各自的优缺点,并从理论上和实际水样测定中论述了TOC和CODCr的相关性。对于不同的废水,TOC 与CODCr的相关性不一样,必须先实验求出二者之间的关系。  相似文献   

18.
A series of laboratory-based incubations using a stable isotope tracer technique was applied to measure the net and gross fluxes of CH(3)Cl and CH(3)Br as well as the net fluxes of CHCl(3) from surface soils of the Sacramento-San Joaquin Delta of California. Annually averaged flux measurements show that these mineral/oxidized peat soils are a net source of CH(3)Cl (140 ± 266 nmol m(-2) d(-1)) and CHCl(3) (258 ± 288 nmol m(-2) d(-1)), and a net sink of CH(3)Br (-2.3 ± 4.5 nmol m(-2) d(-1)). Gross CH(3)Cl and CH(3)Br fluxes are strongly influenced by both soil moisture and temperature: gross production rates of CH(3)Cl and CH(3)Br are linearly correlated with temperature, whereas gross consumption rates exhibit Gaussian relationships with maximum consumption at soil moisture levels between 20 and 30% volumetric water content (VWC) and a temperature range of 25 to 35 °C. Although soil moisture and soil temperature strongly affect consumption rates, the range of gross consumption rates overall is limited (-506 ± 176 nmol m(-2) d(-1) for CH(3)Cl and -12 ± 4 nmol m(-2) d(-1) for CH(3)Br) and is similar to rates reported in previous studies. CHCl(3) fluxes are not correlated with methyl halide fluxes, temperature, or soil moisture. The annual emission rates of CHCl(3) from the Sacramento-San Joaquin Delta are found to be a potentially significant local source of this compound.  相似文献   

19.
Genotoxicity potential of soils taken from wastewater irrigation areas and bioremediation sites was assessed using the Vicia faba root tip micronucleus assay. Twenty five soils were tested, of which 8 were uncontaminated soils and taken as the control to examine the influence of soil properties; 6 soils were obtained from paddy rice fields with a history of long-term wastewater irrigation; 6 soils were obtained from bioremediation sites to examine effects of bioremediation; and 5 PAH-contaminated soils were used to examine methodological effects between direct soil exposure and exposure to aqueous soil extracts on micronuclei (MN) frequency ( per thousand) in the V. faba root tips. Results indicate that soil properties had no significant influences on MN frequencies (p > 0.05) when soil pH varied between 3.4 to 7.6 and organic carbon between 0.4% and 18.6%. The MN frequency measured in these control soils ranged from 1.6 per thousand to 5.8 per thousand. MN frequencies in soils from wastewater irrigation areas showed 2- to 48-fold increase as compared with the control. Soils from bioremediation sites showed a mixed picture: MN frequencies in some soils decreased after bioremediation, possibly due to detoxification; whereas in other cases remediated soils induced higher MN frequencies, suggesting that genotoxic substances might be produced during bioremediation. Exposure to aqueous soil extracts gave a higher MN frequency than direct exposure in 3 soils. However, the opposite was observed in the other two soils, suggesting that both exposure routes should be tested in case of negative results from one route. Data obtained from this study indicate that the MN assay is a sensitive assay suitable for evaluating genotoxicity of soils.  相似文献   

20.
Trichloroacetic acid (TCAA) is a phytotoxic chemical, present throughout the environment. The majority of methods for analysis of TCAA require chemical derivatisation and multiple extraction steps prior to analysis by gas-chromatography. Here, a new analytical method for TCAA determination in environmental matrices is reported. The method is based on a modified Nielsen-Kryger steam distillation that combines into one 1 h reflux the thermal decarboxylation of TCAA to CHCl3 and the partitioning and concentration of the CHCl3 into 5 ml of hexane, which is analysed by GC. Sample preparation is minimal and no matrix standard additions are required. The background CHCl3 in the sample is removed prior to extraction by degassing the solution for 1 h with nitrogen. Optimisation of the method gave recoveries from three separate solutions of 0.31 ppb aqueous TCAA standards of 93 +/- 15% (n = 9), 110 +/- 9% (n = 9) and 105 +/- 11% (n = 6). The extraction method has been compared with a decarboxylation and headspace GC method for determination of TCAA in Sitka spruce needles. No significant difference in TCAA concentration or replicate precision between the two methods was observed.  相似文献   

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