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1.
水体中叶绿素a测定方法的研究   总被引:1,自引:0,他引:1  
对水体中叶绿素a的测定方法进行了研究,确定了乙醇免研法测定水体中叶绿素a的实验条件。用95%乙醇替代90%丙酮作为萃取剂,用高温免研磨萃取替代研磨萃取,其结果是乙醇免研法与丙酮法测定结果的相对偏差在可接受范围内; 同时对测定结果进行统计分析显示, 乙醇法的测定结果与丙酮法无显著性差异,且乙醇免研法萃取效率有所提高,其测定结果均略高于丙酮法,说明乙醇免研法可以替代丙酮法。  相似文献   

2.
气相色谱测定土壤中微量阿特拉津   总被引:6,自引:0,他引:6  
采用丙酮加水提取土壤中的阿特拉津,再用三氯甲烷萃取,经浓缩、定容后,用毛细管气相色谱法测定.  相似文献   

3.
建立了高湿度废气中丙酮的测定方法,直接用顶空瓶采集高湿度废气,然后向顶空瓶中加入超纯水,使顶空瓶中的水量恒定,最后用顶空气相色谱法测定顶空瓶中气体浓度,并研究了水份对丙酮测定的影响。方法具有良好的线性和平行性,相关系数在0.999以上,样品测定的相对标准偏差在5%左右。  相似文献   

4.
研究了用硝基苯并噻唑重氮氨基偶氮苯(NBTDAA)固相萃取光度法测定镉,在pH=10的硼砂-氢氧化钠缓冲介质中,TritonX-100存在下,NBTDAA与镉反应生成2∶1稳定络合物,该络合物可被MCI-GEL 反相固相萃取小柱萃取富集,富集的络合物用丙酮洗脱后用光度法测定,在丙酮介质中体系最大吸收波长为525nm,摩尔吸光系数ε=1.32×105 L·mol-1·cm-1,镉含量在0.01~1.5 mg/L内符合比耳定律,方法用于痕量镉的测定,结果令人满意.  相似文献   

5.
本文建立了用纯水直接吸收环境空气的甲醇和丙酮,利用静态顶空进样,气相色谱进行定性定量测定。对顶空平衡温度、平衡时间、盐加入量等因素进行了优化,并对方法检出限、线性范围和加标回收率进行了测定。该方法最低检出质量浓度为甲醇0.04 mg/m~3,相对标准偏差为3.2%~5.0%,加标回收率为85.8%~102%;丙酮0.004 mg/m~3,相对标准偏差为3.8%~6.5%,加标回收率为87.4%~98.2%,适用于环境空气中甲醇和丙酮的测定。  相似文献   

6.
用组织研磨、浸泡提取、热浴超声3种提取方法和丙酮、甲醇、乙醇3种提取溶剂,从实验室纯培养微囊藻中提取叶绿素a,并以高效液相色谱法测定其质量浓度。结果表明,经组织研磨破碎藻细胞后用甲醇提取的效果好于丙酮和乙醇,经浸泡和超声破碎藻细胞后用乙醇的提取效果好于丙酮和甲醇;使用乙醇-热浴超声法在所有的试验组合中获得最佳提取效果,条件为:乙醇温度为50℃-55℃,超声6min-8min后再静置提取5h-6h。  相似文献   

7.
建立了用GC-FID同时测定空气中乙酸、丙酸的方法.乙酸、丙酸经硅胶管吸附后,用丙酮溶剂解吸,气相色谱分析.优化条件下,在20 ~2 000 mg/L范围内有良好的线性关系.方法检出限分别达到了1.0 mg/m3和0.5 mg/m3,相对标准偏差2.2%和1.9%,回收率在94%以上.  相似文献   

8.
地表水浮游植物叶绿素a测定方法比较研究   总被引:6,自引:0,他引:6  
比较了浮游植物叶绿素a测定方法中的丙酮萃取法和热乙醇萃取法.结果表明,应用反复冻融植物细胞的丙酮萃取法对地表水中浮游植物叶绿素a的萃取率显著高于其他方法,且重复测定的精密度较高.  相似文献   

9.
实验研究了使用100mL玻璃注射器采样,经阀进样器1mL直接进样后经气相色谱法分离FID检测器定量,快速测定空气中丙酮的浓度。丙酮在0~39 mg/m3范围内线性良好,样品中的丙酮在气相色谱条件下响应灵敏,与甲醇和乙酸甲酯等干扰物质能实现良好的基线分离,方法的检出限为0.006mg/m3,测定下限为0.024mg/m3。实验证明此方法可用于快速测定环境空气中的丙酮浓度。  相似文献   

10.
建立了用氧化铝和活性碳作为基质固相分散剂的加速溶剂萃取方法预处理土壤样品中的毒死蜱,用丙酮、甲醇(1∶1,V/V)在加速溶剂萃取仪上以10.3Mpa、60℃提取10 min,萃取液经浓缩定容后,用Agilent 6890气相色谱仪进行检测,土壤中毒死蜱农药的回收率为89.2%~92.8%。该法用于土壤中毒死蜱的农药残留测定,速度快,检出限为0.001 mg/kg。  相似文献   

11.
对空气中甲醛测定的采样方法进行了探讨 ,分别用水和稀硫酸作吸收液对空气甲醛进行采样研究。结果表明 ,用 0 .0 0 5mol LH2 SO4 作吸收液的采样方法 ,可有效、稳定地延长样品的保存时间 ,且又符合方法灵敏度和精密度的要求。  相似文献   

12.
分析了在当前履约压力下环境监测的薄弱与不足之处,提出了拓展环境空气监测内容,将生态调查和多样性监测纳入常规体系,推进有机监测技术发展,加大多边合作与联合监测的发展思路.  相似文献   

13.
14.
为了解泰东河疏浚工程对通榆河水质的影响,于2012年6月8日、9月12日、12月6日,对泰东河沿线以及通榆河东台段进行调查取样,分析施工期间河体水质变化。结果表明,施工期间水质参数基本保持在Ⅱ~Ⅲ类。根据江苏省水环境监测中心盐城分中心2011年、2013年监测资料评价分析,泰东河河道疏浚后,清理了河床淤泥,提高了泰东河的行洪、抗洪以及通航能力,其水质的好转有效地改善了下游通榆河的水质,确保了饮水安全。  相似文献   

15.
The U.S. EPA has prepared a State of the Region Report for Mid-Atlantic Estuaries to increase knowledge of environmental condition for improved environmental management. Sources of information included the National Estuary Programs, the Chesapeake Bay Program, the state monitoring programs in Delaware, Maryland, and Virginia, Federal programs such as National Status & Trends, National Shellfish Register, National Wetlands Inventory, the Environmental Monitoring and Assessment Program, and other primary literature sources. The state of the estuarine environment was summarized using indicators for water and sediment quality, habitat change, condition of living resources, and aesthetic quality. Each indicator was briefly discussed relative to its importance in understanding estuarine condition. Wherever possible, data from multiple programs were used to depict condition. Finally, an overall evaluation of estuarine condition in the region was determined. The usefulness of monitoring programs that collect consistent information with a well-defined sampling design cannot be overemphasized.  相似文献   

16.
Estimating the Ecological Condition of the Estuaries of the Gulf of Mexico   总被引:1,自引:0,他引:1  
Monitoring of estuaries in the Louisianian Province was performed annually from 1991–1994 to assess ecological conditions on a regional scale. We found over the four years of monitoring, 25±6% of Gulf of Mexico estuarine sediments in the Louisianian Province displayed poor biological conditions, as measured by benthic community structure, and 14±7% of the area was characterized by poor water clarity, the presence of marine debris, and elevated levels of fish tissue contaminants. Using statistical associations to discern relationships between ecological condition and exposure or stressor data has shown that much of this degraded' condition co-occurs with sediment contamination.  相似文献   

17.
简述了锅炉的风量和烟气量、锅炉燃料的消耗量以及锅炉运行负荷的估算方法。通过实例分析,用现场监测的实际风量与理论值比较,粗略估算出监测时段锅炉运行负荷,比对锅炉污染物监测时段的锅炉运行负荷标准,从而判断监测数据的准确性与有效性。  相似文献   

18.
环境空气质量标准中各种污染物的浓度限值是评价、考核空气质量状况的基本依据。为了保证在不同时空、不同环境状况下监测数据的可比性,各个国家或组织在制定的空气质量标准中对标准状态(温度和压力)进行了定义。但是,由于标准状态定义不同,即使是同一环境状况下的同一实测结果进行标化计算后的污染物浓度也不相同,达不到可比性的基本原则。因此,建议中国在未来修订空气质量标准所采用的标准状态,进一步与国际接轨。  相似文献   

19.
In 1996, the Smithsonian Tropical Research Institute and the Republic of Panama's Environmental Authority, with support fromthe United States Agency for International Development, undertook a comprehensive program to monitor the ecosystem of the Panama Canal watershed. The goals were to establish baselineindicators for the integrity of forest communities and rivers. Based on satellite image classification and ground surveys, the2790 km2 watershed had 1570 km2 of forest in 1997, 1080 km2 of which was in national parks and nature monuments. Most of the 490 km2 of forest not currently in protected areas lies along the west bank of the Canal, and its managementstatus after the year 2000 turnover of the Canal from the U.S. to Panama remains uncertain. In forest plots designed to monitorforest diversity and change, a total of 963 woody plant specieswere identified and mapped. We estimate there are a total of 850–1000 woody species in forests of the Canal corridor. Forestsof the wetter upper reaches of the watershed are distinct in species composition from the Canal corridor, and have considerably higher diversity and many unknown species. Theseremote areas are extensively forested, poorly explored, and harbor an estimated 1400–2200 woody species. Vertebrate monitoring programs were also initiated, focusing on species threatened by hunting and forest fragmentation. Large mammals are heavily hunted in most forests of Canal corridor, and therewas clear evidence that mammal density is greatly reduced in hunted areas and that this affects seed predation and dispersal. The human population of the watershed was 113 000 in 1990, and grew by nearly 4% per year from 1980 to 1990. Much of this growth was in a small region of the watershed on the outskirts of Panama City, but even rural areas, including villages near and within national parks, grew by 2% per year. There is no sewage treatment in the watershed, and many towns have no trashcollection, thus streams near large towns are heavily polluted. Analyses of sediment loads in rivers throughout the watershed did not indicate that erosion has been increasing as a result ofdeforestation, rather, erosion seems to be driven largely by total rainfall and heavy rainfall events that cause landslides.Still, models suggest that large-scale deforestation would increase landslide frequency, and failure to detect increases inerosion could be due to the gradual deforestation rate and the short time period over which data are available. A study of runoff showed deforestation increased the amount of water fromrainfall that passed directly into streams. As a result, dry season flow was reduced in a deforested catchment relative to aforested one. Currently, the Panama Canal watershed has extensive forest areasand streams relatively unaffected by humans. But impacts of hunting and pollution near towns are clear, and the burgeoningpopulation will exacerbate these impacts in the next few decades.Changes in policies regarding forest protection and pollution control are necessary.  相似文献   

20.
As part of the monitoring program from Instituto Hidrográfico, since 1981 sediment and water samples have been collected from four different estuarine areas located along the continental coast of Portugal. The concentrations of different parameters were measured in the water and sediment samples. After normalization, the concentrations of chromium, mercury, lead and zinc in the sediments from the different areas were compared.  相似文献   

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