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1.
废水的BOD5测定中取稀释比是一个很重要的问题。本文根据数学推导得出BOD5测定中取稀释比的一种方法。BOD5/CODcr值在0.05-0.1,0.1-0.3,0.3-0.6,0.6-1.0四个范围内其稀释比f2可对应取55/CODcr、22/CODcr、9/CODcr、5/CODcr。  相似文献   

2.
气相分子吸收光谱法测定废水中硫化物   总被引:2,自引:0,他引:2  
应用分子吸收光谱地不同行业废水中的硫化物进行了测定。当水样不含干扰物质时可直接测定,否则需经沉淀、过滤、洗涤前处理。进行一与碘量法和吹气-对氨基二甲基苯胺光度法的对比试验,所测结果较为一致。分子吸收光谱法的线性范围为0.1mg/L ̄4.0mg/L。取5mL样品直接测定,检测限为0.05mg/L;取5mL样品沉淀等有处理后,检测限为0.005mg/L。测定速度快,直接测定最多2min即可测一个样品;  相似文献   

3.
水中总酚量的紫外分光度法的测定   总被引:3,自引:0,他引:3  
为简化光度法测定水中总酚量的操作,对紫外分光光度法测定废水中总酚的方法进行改进,用碱性水溶液代替水溶液,选择λ=235mm作为测定波长,对标准样品和实际废水样品进行测试,在pH=10~12之间,相对误差为0.5%~1.0%,相对标准偏差为0.2%~3.0%,回收率99%~102%之间,检测范围(0.05~5)mg/L苯酚。结果准确可靠,快速、简便、成本低、易于实现自动化分析。进行适当改进,可用于自动监测。  相似文献   

4.
假定样品经过培养后耗氧率达55%;推导出BOD5稀释倍数K=BOD5/4.4,由稀释程度规定推导出BOD5稀释倍数K=(BOD5-1)/4.0两种方法K基本相同,标准样品,工业废水经上述方法稀释后,测定结果比较满意,尤其对工业废水测定,既缩短了分析时间,又降低了测定误差。  相似文献   

5.
合成了新试剂4-(H-酸偶氮)1-苯基-3-甲基吡唑酮(HPMP),研究了其和铜的显色反应。在pH=7的NH4Ac缓冲介质中,CTMAB存在下,HPMP与Cu(Ⅱ)生成2∶1紫色络合物,λmax=580nm,ε=5.68×104L·mol-1·cm-1。铜含量在0~0.6mg/L内符合比耳定律。方法用于水样和生物样品中铜的测定,结果令人满意。  相似文献   

6.
在十二烷基硫酸钠,氟化钠和盐酸羟胺存在下,PH=5.2~7醋酸-醋酸钠缓冲溶液中,Cu(Ⅱ),Fe(Ⅱ)分别与5-CI-PADAB形成紫红色络合物。选择测定波长为530nm,铜和铁的摩尔吸光系数分别为52×104L·mol-1·cm-1,60×104L·mol-1·Cm-1.铜和铁分别在0~12ug/10ml和0~10ug/10m1范围内符合比尔定律。选用了硫代硫酸钠-硫脲褪色液和EDTA掩蔽剂,直接用于血清及水中铜和铁的连续测定,结果满意。  相似文献   

7.
卫生纸中痕量有机氯农药的残留分析习志群,姚渭溪,曹学丽(中国科学院生态环境研究中心,北京100085)①样品提取:称取10g纸样,卷成纸筒置于500ml索氏提取器内,加入200ml正己烷:丙酮=1:1的混合溶液浸泡过夜。然后再加入80ml混合液加热徊...  相似文献   

8.
测定水中亚硝酸盐氮絮凝方法的改进赵敏(深圳市宝安区环境保护局518101)根据《水和废水监测分析方法》,水中亚硝酸盐氮的测定采用N-(1-萘基)-乙二胺光度法,方法原理是:在磷酸介质中,pH=1.8±0.3时,亚硝酸盐与对氨基苯磺酰胺反应,生成重氮盐...  相似文献   

9.
以1,2,4-三甲苯为内标,采用气相色谱/质谱联机的选择离子监测法(STM)对生产车间及周围环境空气中的氯上进行监测,检出下限为1.4ng,空气中氯化苄的检出浓度为0.025mg/m^3,回收率为93% ̄105%,具有较好的重现性和准确性。  相似文献   

10.
GEMS/Air介绍(1)1993年监测报告(I)朱玉栋(中国环境监测总站,北京100012)全球环境大气监测(简称为GEMS/Air)1993年在中国的工作情况如下;1.GEMS/Air监测站位情况目前在中国参加GEMS/Air工作的城市共有五个,...  相似文献   

11.
河北省火电企业吨煤烟气排放量测定及污染动态预测   总被引:2,自引:2,他引:0  
火电企业大气污染动态预测是大气污染控制的基础。采用现场实测法,对河北省36家火电企业101台机组锅炉进行现场监测,经统计分析给出不同装机容量吨煤烟气排放量,并与其他方法进行了比较,发现实测结果更为合理。在此基础上,建立吨煤SO2、NOx,烟尘排放量和烟气浓度的关系,为火电企业大气污染动态预测提供新的公式,对定量测定火电企业污染物排放提供参考。  相似文献   

12.
对同一场景中同一机动车排放黑烟的行为,采用光电测烟望远镜和黑烟车电子抓拍系统2种方法测定林格曼黑度,以光电测烟望远镜作基准,对黑烟车电子抓拍系统的测量结果进行修正。结果表明,黑烟车电子抓拍系统的测量结果经修正后与光电测烟望远镜的测试结果的相关性系数约为0.977,误差平均值为-0.015,方差为0.032,说明2种测量方法具有良好的相关性和可比性,利用光电测烟望远镜可以为黑烟车电子抓拍系统搭建量值溯源链。  相似文献   

13.
A monitoring method for diesel particulate matter was published as Method 5040 by the National Institute for Occupational Safety and Health (NIOSH). Organic and elemental carbon are determined by the method, but elemental carbon (EC) is a better exposure measure. The US Mine Safety and Health Administration (MSHA) proposed use of NIOSH 5040 for compliance determinations in metal and nonmetal mines. MSHA also published a rulemaking for coal mines, but no exposure standard was provided. A standard based on particulate carbon is not considered practical because of coal dust interference. Interference may not be a problem if an appropriate size-selective sampler and EC exposure standard are employed. Submicrometer dust concentrations found in previous surveys of nondieselized, underground coal mines were relatively low. If a large fraction of the submicrometer dust is organic and mineral matter, submicrometer EC concentrations would be much lower than submicrometer mass concentrations. Laboratory and field results reported herein indicate the amount of EC contributed by submicrometer coal dust is minor. In a laboratory test, a submicrometer EC concentration of 31 microg m(-3) was found when sampling a respirable coal dust concentration over three times the US compliance limit (2 mg m(-3)). Laboratory results are consistent with surveys of nondieselized coal mines, where EC results ranged from below the method limit of detection to 18 microg m(-3) when size-selective samplers were used to collect dust fractions having particle diameters below 1.5 microm-submicrometer EC concentrations were approximate 7 microg m(-3). In dieselized mines, submicrometer EC concentrations are much higher.  相似文献   

14.
易江 《干旱环境监测》1995,9(3):165-166,182
论述了我国燃煤固定污染源二氧化硫排放总量监测工作中存在的问题,开展了完成的研究课题,实测方法,研制的采样和测试仪器设备等有关大气环境监测管理中一些重要的实际问题。  相似文献   

15.
燃煤锅炉湿法脱硫烟气中颗粒物排放特征   总被引:2,自引:1,他引:1  
选择北京市典型燃煤锅炉进行研究,结果表明:烟气中可凝结颗粒物在总颗粒物中占有较高比例,供热燃煤锅炉总颗粒物排放水平明显高于电厂燃煤锅炉;颗粒物中水溶性离子含量较高,供热燃煤锅炉硫酸根比例尤其显著;烟气总颗粒物中存在大量不稳定的易被氧化的组分;同为燃煤源,不同的烟气净化工艺排放的PM2.5组分特征差异明显;现有标准和技术规范存在不足,无法满足全面、准确监测污染源排放总颗粒物的实际需要。建议建立总颗粒物、可凝结颗粒物的监测技术规范,全面测算燃煤锅炉硫、氮化合物排放情况,科学评估脱硫及脱硝效率。  相似文献   

16.
In India coal production will have to be increased to meat theenergy demand at a very high rate. By 2000 AD the coolproduction from opencast (O/C) mining will rise to 250 Mt. whichwill be about 70% of the total coal production. The increasing trend of O/C mining leads to cause air pollution problem. A surveywas conducted to assess the status of work zone air envirnmentdue to opencast coal mining in Jharia Coalfield. Keeping in viewof place of dust generation air quality monitoring stations wereselected. Methodology adapted for sampling and analysis of airpollutants have been described. Four season data revealed thatmaximum concentration of SPM was observed at dragline sectionand the next high concentration was at haul roads. At all thelocations SPM and RPM concentrations exceeded the permissiblelimits specified by Indian Pollution Control Board. Shift wiseand location wise analysis for getting higher concentration ofSO2 and NOx have been discussed. Wind velocity anddirections, mixing heights, ventilation coefficient of the areahave been analyzed. Huge dust generation creates vision problemto HEMM operators. The methodology adopted may be utilised onindustrial scale for various sites.  相似文献   

17.
对不同类型的炉灶煤耗及污染物的排放量进行了定量计算,在大量的统计资料及监测数据的基础上,分析阿图什市各类型炉灶燃煤及污染物排放的情况,并通过定量计算进行了探讨,提出相关的对策和建议.  相似文献   

18.
The need to collect data representative of overall urban pollution is all-important in order to monitor the population exposure. High spatial resolution monitoring using diffusive samplers allows studying of the urban pollutant distribution, thus enabling deeper investigation of their generation and diffusion mechanisms. Nevertheless, such a monitoring campaign has a certain cost. In this study we point out how to find the best compromise between the number of necessary measurements and the affordable costs for monitoring campaigns. We also describe an innovative method for the proper design of a fixed urban monitoring network by means of preliminary high spatial resolution campaigns using diffusive samplers. Four European capital cities (Dublin, Madrid, Paris and Rome) were monitored six times, each time for seven days. Benzene, toluene, ethylbenzene, xylenes (BTEX) and NO(2) concentrations were measured at 146 sites in Dublin, 293 in Madrid, 339 in Paris and 290 in Rome. Multiscale grids have been drawn which ranged in mesh size from 500 m to 2 km. The statistical processing of data produced a twofold result: the creation of isoconcentration maps with geostatistical procedures, and an algorithm aimed at locating the minimum number of sampling sites where the fixed monitoring stations should be placed. Average urban levels estimated on the basis of these selected sites differ by less than 8% from those calculated on the whole populations of the sampled points. The aim of this work is to investigate how far the resolution of a monitoring campaign of urban pollution by diffusive sampling can be reduced, thus making the monitoring less expensive in terms of human and financial resources, while preserving the same quality of the results that could be achieved with a higher resolution. We found that there is no significant loss of information when the resolution of the monitoring grid for BTEX is lowered to a mesh size of 1.85 km, that is a sampling site each 3.4 km(2), and that the minimum number of sampling sites to be used is N = 0.29 A, where A is the urban surface to be monitored (in km(2)). As the spatial distribution of NO(2) is less sensitive to the distance from the emission source than that of BTEX, this relationship could be retained as a valid lower limit for the mesh grid size also for NO(2) monitoring.  相似文献   

19.
介绍了燃煤电厂烟气排放过程(工况)监控系统的架构,排放过程监控子系统、参数监测子系统和数据采集传输子系统的实现方式,过程监控采集参数选择方法,模型建立步骤与验证方法。结合实际应用,分析如何判定脱硫设施运转正常,烟气参数监测是否正确,并提出了做好过程监控系统工作的相关建议。  相似文献   

20.
厦门的年耗煤量已突破 1 50万吨 ,煤渣与粉煤灰的出路是政府与公众所关注的问题。 1 986年与 1 996年相隔 1 0年的两次放射性水平监测与研究相互印证表明 ,厦门以煤渣砖为建材的建筑物 ,放射性水平低于砖混、砖木、泥木、花岗岩等类的建筑物。厦门煤渣与粉煤灰的核素含量 ,均低于《建筑材料用工业废渣放射性物质限制标准》,从而为厦门煤渣与粉煤灰的开发与推广应用提供了科学依据 ,指出了光明前景  相似文献   

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