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141.
青铜峡铝厂氟污染对广武乡玉米影响的调查分析 总被引:1,自引:0,他引:1
监测了青铜峡铝厂东南方向4.5km的广武乡玉米叶,得知含氟量为43.94-166.1mg/kg,对照样品树新林场玉米叶的含氟均值为13.15mg/kg,广武乡的玉米受到了严重的氟污染,农作物减产严重。 相似文献
142.
Some physicochemical parameters were determined for thirty field water samples collected from different water channels in the Pearl River Delta Economic Zone river system. The analytical results were compared with the environmental quality standards for surface water. Using the SPSS software, statistical analyses were performed to determine the main pollutants of the river water. The main purpose of the present research is to investigate the river water quality and to determine the main pollutants and pollution sources. Furthermore, the research provides some approaches for protecting and improving river water quality. The results indicate that the predominant pollutants are ammonium, phosphorus, and organic compounds. The wastewater discharged from households in urban and rural areas, industrial facilities, and non-point sources from agricultural areas are the main sources of pollution in river water in the Pearl River Delta Economic Zone. 相似文献
143.
A novel analytical method has been established for on-line simultaneous determination of fluorene and acenaphthene,chrysene and benzo[a]anthracene (B[a]A) by polarization synchronous fluoromet.y (PSF) coupled to high performance liquid chromatography (HPLC). The detection limits were: 0.039, 0.046, 0.016 and 0.042 mgL-1 for fluorene, acenaphthene, chrysene and B[a]A, respectively. The proposed method has been successfisily applied to simultaneous determination of these PAHs in environmental air and marine sediment samples. 相似文献
144.
连续采样与五日法采样效果及费用的对比分析 总被引:2,自引:0,他引:2
通过对连续采样与五日法采样五种方法监测结果及所需费用的比较,得出连续采样方法监测结果更具有代表性,合理性,一次性投资大,但运行费用并不高的结论。 相似文献
145.
Faculty position announcement 相似文献
146.
Determination of Trace Organochlorinated Pesticides and Polychlorinated Biphenyls in Water 总被引:1,自引:0,他引:1
Zou Shichun Zhang Zhanxia Sheng Guoying Min Yushun Fu Jiamo 《Environmental monitoring and assessment》1997,44(1-3):563-568
A modified steam distillation liquid-liquid extraction (SDE) device is developed for the enrichment of trace organochlorinated pesticides (OCPs) and polychlorinated biphenyls (PCBs) in up to one litre of water samples. One ml of n-hexane is sufficient to extract the analytes. The extract can be analysed directly by a capillary gas chromatography-electron capture detector. The recoveries range from 84.6 to 102.3% for OCPs and 80.5 to 106.2% for PCBs, respectively. Matrice materials such as lipids and humic substances were removed by the SDE method from the extract and no further cleanup and concentration steps were needed. 相似文献
147.
通过实验与实际工程相结合,定量描述了大气采样系统中金属氧化物的存在对SO2测定值的影响,并阐述了其反应机理,提出了相应措施。 相似文献
148.
朱喜 《环境监测管理与技术》1996,8(5):18-19
监测结果表明,梅梁湖水体TP,TN含量分别为0.1mg/L和3.4mg/L藻类生物量达9-13亿个细胞/L,富营养化相当严重,污染的主要原因,工农业,渔业,畜牧业和生活污水的直接排放,使水全营养盐含量较高,藻类大量繁殖,可采用“控源截汛”,“清除淤泥”,“调水搞活”及生物治理等综合性措施,对梅梁湖的富营养化进行了治理。 相似文献
149.
Solvent microextraction (SME) was applied to the extraction of polycyclic aromatic hydrocarbons (PAHs) from spiked and real environmental soil samples with different matrices. Soil sample was mixed with 7 mL of acetone and 14 mL of water to allow partitioning of the PAHs from the soil to the liquid phase. A 2 microL octane drop suspended from a microsyringe needle tip was then immersed into the stirred solution-soil mixture for extraction. After an 11 min extraction, the octane drop was withdrawn into the syringe and injected directly into the GC for identification and quantification. The whole analysis procedure took 27 min, with an extraction time of 11 min, and a GC separation time of 16 min. A second extraction could be undertaken whilst the GC is running, hence the GC run time currently limits the sample throughput. In this method, a small amount of organic solvent was used for the extraction process, which produced little waste. The limits of detection for lower molecular weight (< 230) PAHs range from 0.13 to 0.36 mg kg-1, and for higher molecular weight (> 250) PAHs are estimated to be between 0.5 and 1.0 mg kg-1, with RSD values generally under 20%. Due to the small volumes of organic solvent used, the consumable cost per extraction is only US$ 0.12. This is the first report of the application of SME to solid samples, and the first report of the use of SME for the analysis of PAHs. 相似文献
150.
用密切值法评价沙湾荒漠区生态环境质量 总被引:3,自引:0,他引:3
利用多目标决策中的密切值法进行沙湾荒漠区生态环境综合评价。该方法简便、适用、且分辨率较高,对各监测点群的定量描述符合实际状况。 相似文献