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581.
Gon Ok Sung-Hee Ji Sang-Jo Kim Young-Kyo Kim Ji-Hoon Park Young-Seup Kim Young-Ho Han 《Chemosphere》2002,46(9-10)
The atmospheric contamination levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were evaluated from the analysis of pine needles in South Korea. Pine needles were collected from 30 sampling points at five main cities in South Korea (Busan, Daegu, Gwangju, Changwon and Jeju island). The highest concentrations of PCDDs/DFs (2.19–26.88 pg I-TEQ/g of dry weight) were measured at Busan, where is the city of the highest population density and traffic volume among five cities. The lowest concentration was detected at Jeju with 0.62 pg I-TEQ/g dry weight, suggesting Jeju could be an environmental background area in Korea. The dominant homologues of PCDDs/DFs in pine needles were the lower chlorine-substituted compounds such as tetra CDDs and CDFs, and the distribution ratios of PCDDs/DFs decreased with increase of the number of chlorine substituents. Homologue profiles of pine needle samples were similar to PCDDs/DFs profiles of the vapor phase in the ambient air, and thus the pine needles absorbed the vapor phase of PCDDs/DFs from air. Results suggested that pine needles could be used as an indicator of the atmospheric contamination for PCDDs/DFs in Korea. 相似文献
582.
R.L. Harless E.O. Oswald R.G. Lewis A.E. Dupuy D.D. McDaniel Han Tai 《Chemosphere》1982,11(2):193-198
Validated sample preparation procedures and high resolution gas chromatography-high resolution mass spectrometry techniques were utilized for the quantitative measurement of 4 to 695 pg/g (ppt) levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2378-TCDD) in the edible portions of fish from the state of Michigan. The methodology and the analytical results are presented. 相似文献
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584.
Trace analysis of dissolved polychlorinated organic compounds in the water of the Yangtse River (Nanjing, China) 总被引:15,自引:0,他引:15
Sun C Dong Y Xu S Yao S Dai J Han S Wang L 《Environmental pollution (Barking, Essex : 1987)》2002,117(1):9-14
Eighteen organochlorine contaminants from the water samples of the Yangtse River have been qualitatively and quantitatively analyzed. The analysis of polychlorinated organic compounds (PCOCs) extracted by C18 Solid Phase Extract (SPE) was performed using HP6890 gas chromatograph coupled by ECD detector. The analytical results demonstrate that the analytical methods are reliable based on the fact that most of the recoveries for the targeted compounds are 60-90%. Most of the concerned contaminants, i.e. chlorinated pesticides and PCBs were found in the water samples of the Yangtse River, but their concentration was very low, <2.97 ng l(-1), which is far less than 1 microg l(-1)--the standard of drinking water of China. It is apparent that the PCOCs were in high concentration during the dry season, and in low concentration during the rainy season. The situation of PCOCs contamination in the water of the Yangtse River in 1999 was greatly improved in comparison with 10 years ago. 相似文献
585.
在分析中 ,对混凝法处理铝合金废水所得污泥再利用进行了研究 ,得到了适宜的操作条件。结果表明 ,用浓硫酸溶解污泥的最佳用量为 0 0 6— 0 0 8mL/g湿污泥 ,污泥的溶解率可达 80 % ,铝的溶出率也可达 90 %以上。把污泥的溶解液作混凝剂回用于废水的混凝处理也取得了良好的效果。 相似文献
586.
A series of reactions was carried out on different surfaces using carbon and CuCl2, and KCl or HCl as a Cl-source. The PCDD/PCDF congener distribution was seen to vary to a great extent but the isomer distribution remained fairly constant. It is concluded that thermodynamic properties are largely responsible for the PCDD/PCDF isomer distribution. With pentachlorobenzene Cl2 elimination, assisted by oxygen, appears to be the major pathway for PCDD/PCDF formation. 相似文献
587.
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589.
二氧化氯销毁氰化物的应用研究 总被引:1,自引:0,他引:1
在弱碱性条件下,二氧化氯消毒剂将氰化物氧化成无毒的氰酸盐(OCN)、二氧化碳和氮气。研究了影响二氧化氯销毁氰化物的几种因素:pH在8—11的范围内,不影响二氧化氯对氰化物的销毁率;在所试验的反应温度(0-40℃)内,温度对反应速率表现出有限的影响;二氧化氯与氰离子的最佳质量比为2:1;当氰离子最高使用浓度小于0.5g/L时,废水中氰离子浓度达一级以上的排放标准。 相似文献
590.
Indigenous knowledge of edible fungi and their utilization by local populations were investigated in southern Cameroon from 1996 to 1999. Some 100 participants from the major ethnic groups, comprising Bantu farmers and Bagyeli (Pygmy) hunter-gatherers, were interviewed. Mushroom usage by 30 families, (319 persons), was monitored daily for over a year. Mushroom knowledge among both groups was extensive. Over 50 vernacular names were provided by respondents. In Bantu households, women and children, and to some extent hunters, harvest mushrooms. In contrast, the whole Bagyeli household participates. Bantu harvest mushrooms preferentially in secondary forests while Bagyeli collect them predominantly in primary forests. Mushroom consumption is low for both groups, 1.1 and 1.4 kg of fresh mushrooms per person per year, respectively, a rate that is much lower than in central and eastern Africa. The apparent discrepancy between extensive mushroom knowledge and rather infrequent mushroom consumption probably relates to the social valuation of mushrooms. 相似文献