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231.
Persulfate can efficiently decolorize azo dyes through oxidizing these compounds, which enabled us to develop a method of rapid spectrophotometric determination of persulfate for monitoring the wastewater treatment on the basis of the oxidation decolorization of azo dyes. Four azo dyes with different molecular structures were investigated as probes, and the influences of operation parameters including reaction time, solution pH, initial dye concentration, and initial concentration of activator Fe(2+) were checked on the determination of persulfate. Under optimum conditions, the decolorization degree of the dyes responded linearly with persulfate concentration for all the four azo dyes, and the linear range and detection limit were found to be 2.0-150 μmol L(-1) and 0.62 μmol L(-1) for rhodamine B, 2.0-100 μmol L(-1) and 0.42 μmol L(-1) for methylene blue, 4.0-150 μmol L(-1) and 0.50 μmol L(-1) for methyl violet, and 20-150 μmol L(-1) and 8.1 μmol L(-1) for orange II. A persulfate treatment of a spiked wastewater sample was satisfactorily monitored with the new method. 相似文献
232.
Eight heavy metals (Cu, Zn, Fe, Mn, Cd, Cr, Ni, and Pb) in 14 different wild-growing edible mushroom species (Coprinus comatus, Voluariella volvacea, Pleurotus nebrodensis, Hypsizigus marmoreus, Hericium erinaceus, Agrocybe aegerita, Lenfinus edodes, Collybia velutipes, Agaricus bisporus, Russula albida, Clitocybe conglobata, Pleurotus eryngii, Lepista sordida, and Pleurotus ostreatus) collected from Yunnan province, China, were determined by inductively coupled plasma-atomic emission spectrometry after microwave digestion. All element concentrations were determined on a dry weight basis. The ranges of element concentrations for copper, zinc, iron, manganese, cadmium, chromium, nickel, and lead were 6.8-31.9, 42.9-94.3, 67.5-843, 13.5-113, 0.06-0.58, 10.7-42.7, 0.76-5.1, and 0.67-12.9 mg/kg, respectively. In general, iron content was higher than other metals in all mushroom species. The levels of zinc, cadmium, and lead in some edible mushroom samples were found to be higher than legal limits. The relative standard deviations were found below 10%. The accuracy of procedure was confirmed by certified reference material. 相似文献
233.
Characterization of ambient black carbon and wood burning particles in two urban areas 总被引:1,自引:0,他引:1
Previously it has been suggested that certain organic aerosol components of wood smoke have enhanced ultraviolet absorption at 370 nm relative to 880 nm in two-wavelength aethalometer measurements. This enhanced absorption could serve as an indicator of wood burning particles. Two-wavelength (370 nm and 880 nm) aethalometer measurements were made at urban sites in Rochester, New York and Laredo, Texas from August 1 to December 31, 2009 and from December 23, 2007 to January 2, 2008, respectively. In Rochester, Delta-C (UVBC(370 nm)- BC(880 nm)) values were higher by a factor of 3 during the night than during the day in November and December when residential wood burning was common. In Laredo, particularly high Delta-C values were observed on Christmas Eve and New Year's Eve and were attributed to biomass burning and firework emissions. Exponential decay was found to be a good estimator for predicting BC concentrations at different wind speeds regardless of wind directions. 相似文献
234.
研究利用 UASB反应器考察了 COD和硫酸盐浓度的比值对硫酸盐还原的影响 ,同时分析了硫酸盐还原菌和产甲烷菌对COD的竞争情况 .发现在 HRT为 3.8h,SO2 -4 负荷为 6~ 7kg· ( m3· d) - 1 ,SO2 -4 浓度为 1 0 0 0 mg· L- 1 条件下 :1在 COD不足时 ,SRB与 MPB在竞争中占微弱优势 ;对于产甲烷活性比较好的厌氧污泥要经过较长的时间 ,SRB才能确立优势菌种的地位 .2 COD/ SO2 -4 比值决定了 SO2 -4 的去除率 .比值等于 2时 ,SO2 -4 的还原率在 95%以上 ;当比值为 1 .5时 ,SO2 -4 还原率为 75% ;当比值为 1时 ,SO2 -4 的还原率为 60 % . 相似文献
235.
上海地铁车站恶臭气体污染调查 总被引:2,自引:0,他引:2
对地铁一号线人民广场站和漕宝路站的臭污染情况进行了调查,采用嗅沉测试和公众调查方法对恶臭进行测试和分析。结果表明,人民广场站的IAQ以3级(明显)为主、漕宝路站以2级(轻微)为主,污染程度与人流量和通风状况相关,漕宝路站的空气质量明显好于人民广场站。 相似文献
236.
为了解不同形式坡道式 车库中汽车尾气污染状况,对4座典型的坡道式停车库进行了空气质量监测,并同时进行车流量统计、计算和分析了信车库内污染物浓度与车流量之间的相关性,监测结果表明,停车库NOx和CO浓度符合相应标准,而地下停车库排气Ox有超桔现象。结论是地面停车主轵成于地下停车库,地下停车库的送排风系统必须合理设置。 相似文献
237.
文中利用市及旗县区监测站近几年监测数据对西辽河上游的污染程序进行了讨论 ,并进行了趋势分析 ,提出污染防治对策 ,旨在为辽河治理提供参考 相似文献
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