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Plant uptake of aldicarb from contaminated soil and its enhanced degradation in the rhizosphere 总被引:3,自引:0,他引:3
Experiments were conducted to investigate the degradation of aldicarb, an oxime carbamate insecticide, in sterile, non-sterile and plant-grown soils, and the capability of different plant species to accumulate the pesticide. The degradation of aldicarb in soil followed first-order kinetics. Half lives (t1/2) of aldicarb in sterile and non-sterile soil were 12.0 and 2.7 days, respectively, which indicated that microorganisms played an important part in the degradation of aldicarb in soil. Aldicarb disappeared more quickly (p< or =0.05) in the soil with the presence of plants, and t1/2 of the pesticide were 1.6, 1.4 and 1.7 days in the soil grown with corn, mung bean and cowpea, respectively. Comparison of plant-promoted degradation and plant uptake showed that the enhanced removal of aldicarb in plant-grown soil was mainly due to plant-promoted degradation in the rhizosphere. 相似文献
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炭素焙烧炉沥青烟净化处理 总被引:1,自引:0,他引:1
采用干式静电除尘技术,对炭素焙烧炉排放的含有烟尘、沥青烟的工业废气进行处理,达到既能高效净化有害气体,又能降低资金投入。处理后的各项指标为:烟尘排放浓度=20.0mg/m3,沥青烟排放浓度=14.2mg/m3,苯并(a)芘排放浓度=0.054×10-3mg/m3,所有污染物均达到排放标准。 相似文献
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Methane fluxes were measured from three exposed tundra sites and four snowpack sites on the Fildes Peninsula in the maritime Antarctic in the summertime of 2002. The average fluxes at two normal tundra sites were −15.3 μg m−2 h−1 and −14.3 μg m−2 h−1, respectively. The fluxes from tundra site with fresh penguin dropping addition showed positive values with the average of 36.1 μg m−2 h−1, suggesting that the deposition of fresh droppings greatly enhanced CH4 emissions from the poor Antarctic tundra during penguin breeding periods. The summertime variation in CH4 flux was correlated with surface ground temperature and the precipitation. The correlation between the flux and PT0, which is the product of the precipitation and surface ground temperature, was quite strong. The diurnal cycle of CH4 flux from the tundra soils was not obtained due to local fluky weather conditions. The fluxes through four snowpack sites were also obtained by the vertical CH4 concentration gradient and their average fluxes were −46.5 μg m−2 h−1, −28.2 μg m−2 h−1, −46.4 μg m−2 h−1 and −17.9 μg m−2 h−1, respectively, indicating that tundra soils under snowpack also consume atmospheric CH4 in the maritime Antarctic; therefore these fluxes could constitute an important part of the annual CH4 budget for Antarctic tundra ecosystem. 相似文献
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超声-过氧化氢-氧化铜组合技术催化氧化水中苯酚 总被引:4,自引:0,他引:4
研究了超声-H2O2-CuO组合技术对苯酚的降解效果。考察了苯酚初始浓度、溶液温度及鼓入空气对苯酚去除率的影响。实验结果表明,与未鼓入空气时相比,连续鼓气时苯酚的降解效果较好;初始浓度低,苯酚去除率高;溶液温度从20%上升到55%时,苯酚去除率随温度升高而增大,温度对该过程的影响主要表现为对催化剂的影响而不是对超声作用的影响。高效液相色谱分析表明,苯酚降解的中间产物主要为对苯二酚、邻苯二酚及其他有机小分子物质,最终产物为草酸、二氧化碳和水。 相似文献