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职业接触苯乙烯工人静脉血中蛋白质环氧苯乙烯加合物的分析测定 总被引:1,自引:0,他引:1
静脉血中蛋白质-环氧苯乙烯(SO)加合物的分析测定是将蛋白质中半胱氨酸残留经分解后,用Raney Ni催化反应生成两种加合物:α-苯己醇,β-苯已醇,再用五氟苯氯衍生,GC/MS测定,用同样的方法测SD大鼠血的蛋白质加合物,结果表明动物血中蛋白质加的与实验的苯乙烯或SO剂量有较好的相关性;而且SO与半胱氨酸的反应α位强于β位,在人群实验中,对一个石棉厂职业接触苯乙烯工人静脉血中的蛋白质加合物进行测 相似文献
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A laboratory study demonstrated that ferrate pretreatment significantly enhanced lead and cadmium removal in alum coagulation, under the conditions of natural surface water. The enhancement of lead removal was approximately 21 to 37% by ferrate pretreatment at a dosage of 1 to 5 mg/L. The enhanced removal of cadmium by ferrate pretreatment at a dosage of 1 to 5 mg/L exceeded the removal by alum coagulation alone 2-to 12-fold. Cadmium is much more difficult to remove than lead in alum coagulation. The performance of ferrate in enhancing the removal of lead and cadmium in alum coagulation was better than that of ferric chloride. The removal of lead and cadmium was highly pH-dependent, following the general trend of higher pH being related to higher removal. Satisfactory removal of cadmium could be expected by ferrate pretreatment combined with adjusting the pH of the water. 相似文献
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Influence of hydrogeochemical processes on zero-valent iron reactive barrier performance: a field investigation 总被引:1,自引:0,他引:1
Geochemical and mineralogical changes were evaluated at a field Fe0-PRB at the Oak Ridge Y-12 site concerning operation performance during the treatment of U in high NO3- groundwater. In the 5-year study period, the Fe0 remained reactive as shown in pore-water monitoring data, where increases in pH and the removal of certain ionic species persisted. However, coring revealed varying degrees of cementation. After 3.8-year treatment, porosity reduction of up to 41.7% was obtained from mineralogical analysis on core samples collected at the upgradient gravel-Fe0 interface. Elsewhere, Fe0 filings were loose with some cementation. Fe0 corrosion and pore volume reduction at this site are more severe due to the presence of NO3- at a high level. Tracer tests indicate that hydraulic performance deteriorated: the flow distribution was heterogeneous and under the influence of interfacial cementation a large portion of water was diverted around the Fe0 and transported outside the PRB. Based on the equilibrium reductions of NO3- and SO4(2-) by Fe0 and mineral precipitation, geochemical modeling predicted a maximum of 49% porosity loss for 5 years of operation. Additionally, modeling showed a spatial distribution of mineral precipitate volumes, with the maximum advancing from the interface toward downgradient with time. This study suggests that water quality monitoring, coupled with hydraulic monitoring and geochemical modeling, can provide a low-cost method for assessing PRB performance. 相似文献
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Geochemical and mineralogical changes were evaluated at a field Fe0-PRB at the Oak Ridge Y-12 site concerning operation performance during the treatment of U in high NO3- groundwater. In the 5-yr study period, the Fe0 remained reactive as shown in pore water monitoring data, where increases in pH and the removal of certain ionic species persisted. However, coring revealed varying degrees of cementation. After 3.8-yr treatment, porosity reduction of up to 41.7% was obtained from mineralogical analysis on core samples collected at the upgradient gravel-Fe0 interface. Elsewhere, Fe0 filings were loose with some cementation. Fe0 corrosion and pore volume reduction at this site are more severe due to the presence of NO3- at a high level. Tracer tests indicate that hydraulic performance deteriorated: the flow distribution was heterogeneous and under the influence of interfacial cementation a large portion of water was diverted around the Fe0 and transported outside the PRB. Based on the equilibrium reductions of NO3- and SO4(2-) by Fe0 and mineral precipitation, geochemical modeling predicted a maximum of 49% porosity loss for 5 yr of operation. Additionally, modeling showed a spatial distribution of mineral precipitate volumes, with the maximum advancing from the interface toward downgradient with time. This study suggests that water quality monitoring, coupled with hydraulic monitoring and geochemical modeling, can provide a low-cost method for assessing PRB performance. 相似文献
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