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211.
Effects of algae Nitzschia hantzschiana, Fe(Ⅲ) ions, humic acid, and pH on the photochemical reduction of Hg(Ⅱ) using the irradiation of metal halide lamps (λ 365 nm, 250 W) were investigated. The photoreduction rate of Hg(Ⅱ) was found to increase with increasing concentrations of algae, Fe(Ⅲ) ions, and humic acid. Alteration of pH value affected the photoreduction of Hg(Ⅱ) in aqueous solution with or without algae. The photoreduction rate of Hg(II) decreased with increasing initial Hg(Ⅱ) concentration in aqueous solution in the presence of algae. The photochemical kinetics of initial Hg(Ⅱ) and algae concentrations on the photoreduction of Hg(Ⅱ) were studied at pH 7.0. The study on the total Hg mass balance in terms of photochemical process revealed that more than 42% of Hg(Ⅱ) from the algal suspension was reduced to volatile metallic Hg under the conditions investigated. 相似文献
212.
Mercury (Hg) contents in ten chemical fertilizers were determined, and the e ect of calcium superphosphate (CSP) on the uptake
and translocation of Hg in corn seedlings was investigated by pot experiments. CSP was applied at the levels of 0, 66.7, and 133.4 mg
P2O5/kg to Hg-treated (2 mg/kg) and untreated soils. CSP had the highest Hg content (5.1 mg/kg), followed by the NPK compound
fertilizer 15-5-5 (15% N, 5% P2O5, 5% K2O) (1.2 mg/kg), then by nitrogen fertilizers (except for ammonia sulfate) and potassium
fertilizers. Application of CSP did not obviously influence the biomass of corn roots, but it significantly increased the biomass of corn
shoots in Hg-treated soil. Application of CSP at the levels of 66.7 and 133.4 mg P2O5/kg did not obviously influence the uptake of Hg
by corn seedlings on soils without Hg treatment, but it decreased the Hg uptake of corn seedlings significantly on Hg-treated soils. The
transfer coe cient of Hg in corn seedlings improved slightly on soils without Hg treatment, but decreased slightly on Hg-treated soils
with the application of CSP. These results implied that CSP could ameliorate Hg toxicity to corn seedlings by inhibiting the uptake and
the translocation of Hg in plants on Hg-polluted soils. 相似文献
213.
微波消解ICP-AES测定电子电器产品中Pb、Cd、Hg、Cr方法的研究 总被引:1,自引:0,他引:1
对微波消解ICP-AES(电感耦合等离子体原子发射光谱法)测定电子电器产品中Pb、Cd、Hg、Cr的方法进行了初步研究,以期为准确检测电子电器中重金属类有害物质的分析方法提供参考.结果表明,所采用的微波消解法对欧洲标准参考物质中Pb、Cd、Hg、Cr的回收率分别为93%、86%、89%和90%.多因素实验所确定的最佳工作参数为功率1.2 kW,等离子气流量15 L/min,雾化气压200 kPa,观察高度10 mm.此条件下Pb、Cd、Hg、Cr的加标回收率均在95%~103.3%之间,测定相对偏差小于0.1,相对标准偏差小于1.5%,元素检出限低. 相似文献
214.
215.
Alexis Knight Satyendra P. Bhavsar Brian A. Branfireun Peter Drouin Ram Prasha Steve Petro Moustapha Oke 《环境科学学报(英文版)》2019,31(6):137-145
The use of biopsy plugs to sample fish muscle tissue for mercury analyses is a viable alternative to lethal sampling; however, the practice has yet to be widely implemented in routine monitoring due to concerns about variability of mercury concentrations in fish muscle tissues. Here we examine distribution of mercury in fillets of four fish species (Walleye, Northern Pike, Smallmouth Bass and Lake Trout), suitability of left/right side of fillet for biopsy sampling, and appropriateness of re-using a biopsy punch. The results showed that average mercury concentrations in left and right fillets of fish are similar. Mercury concentrations in biopsy plug samples, taken from the anterior dorsal area of the fish fillet, were statistically equivalent to the mercury concentrations in homogenized fillets. There was no discernible cross contamination between samples when a biopsy punch was reused after washing in hot soapy water, and as such, biopsy punches can be recycled during sampling to reduce the sampling cost. If a tissue mass collected from a specific site on the fillet is insufficient, then we suggest sampling corresponding locations on the other fillet rather than sampling two adjacent sites on one fillet to obtain more tissue. The results presented here can improve the accuracy of fillet biopsy plug sampling, minimize fish mortality for mercury monitoring, and reduce labor and material costs in monitoring programs. 相似文献
216.
燃煤飞灰对锅炉烟道气中Hg0的吸附特性 总被引:1,自引:0,他引:1
在实验室模拟研究了燃煤飞灰颗粒组分对燃煤烟道气中气相Hg的吸附脱除特性.试验结果表明,Hg吸附量随飞灰烧失量的增长而增大,飞灰中不同类型介质的气相Hg吸附特性差异显著,其中未燃尽炭的Hg吸附性能最强,吸附剂BET比表面积与其Hg吸附量呈正相关关系.载气气相Hg浓度与Hg吸附量成非线性正相关关系,即Hg浓度为5×10-7时的Hg吸附量只有5×10-6的1/2.吸附温度与Hg吸附量呈较显著负相关关系.残炭表面的含氧官能团C=O有利于Hg的氧化和化学吸附.燃煤飞灰炭粒所具有的多孔隙结构和巨大比表面积有利于吸附脱除烟道气中Hg污染物. 相似文献
217.
开封周边地区地表灰尘砷、汞背景值及其应用 总被引:3,自引:3,他引:3
在开封市周边地区采集96个地表灰尘样品和49个表土样品,用冷原子荧光法测定样品As、Hg含量,计算灰尘和土壤As、Hg背景值,并以开封城市地表灰尘为例,用地积累指数法(Igeo)和污染负荷指数法(PLI)分别开展基于灰尘和土壤背景值的污染评价.结果表明,开封市附近地区地表灰尘As、Hg背景值分别为8.04 mg·kg-1和22.37μg·kg-1,低于其土壤背景值,也低于我国潮土背景值.同一地区灰尘As、Hg背景值小于土壤,这主要与灰尘和土壤的有机质含量、颗粒大小、农业生产活动有关.基于灰尘背景值的开封城市地表灰尘As、Hg的Igeo和PLI,都大于基于我国潮土背景值的Igeo和PLI.因此,多数学者应用我国潮土背景值开展灰尘污染评价,其污染程度实质上被低估了. 相似文献
218.
219.
桐花树是我国主要的广布种红树植物,具有泌盐性。通过胁迫实验,研究桐花树幼苗叶片生理生态指标对气态单质汞(Hg0)胁迫的响应,以期了解红树植物吸收和富集气态汞的机制。结果表明:气态汞胁迫造成桐花树叶片可溶性糖含量、过氧化物酶(POD)活性下降;而丙二醛(MDA)、脯氨酸、超氧化物歧化酶(SOD)等指标上升;叶绿素含量、过氧化氢酶(CAT)活性出现先升高后降低的趋势,还原型谷胱甘肽(GSH)含量则先降低后升高。总之,虽然Hg0胁迫可增加桐花树幼苗叶的膜质过氧化程度,影响其生理代谢活动,但其叶片可通过调节抗氧化酶活性及还原型谷胱甘肽含量来提高自身抗氧化能力,进而提高对Hg0的抗性。 相似文献
220.