石油套管用钢(/%:0.26~0.29C,0.25~0.35Si,0.40~0.50Mn,≤0.009P,≤0.004S,0.95~1.05Cr,0.09~0.11V,0.02~0.04Al,0.015~0.020Ti,≤0.006 0N)的生产流程为铁水预处理-120 t BOF-吹氩-LF-喂CaSi线-RH-合金化-喂CaSi线-软吹氩-Φ220 mm圆...石油套管用钢(/%:0.26~0.29C,0.25~0.35Si,0.40~0.50Mn,≤0.009P,≤0.004S,0.95~1.05Cr,0.09~0.11V,0.02~0.04Al,0.015~0.020Ti,≤0.006 0N)的生产流程为铁水预处理-120 t BOF-吹氩-LF-喂CaSi线-RH-合金化-喂CaSi线-软吹氩-Φ220 mm圆坯连铸工艺。通过热力学分析得出钢中N含量超过50×10^(-6)以及工业试验得出生产的圆铸坯中的N含量为67×10^(-6)时,在铸坯中易形成2μm以上的TiN夹杂。通过控制BOF终点[N]≤30×10^(-6),LF终点[S]≤25×10^(-6),[O]≤25×10^(-6),[N]≤35×10^(-6),RH合金化后终点[N]≤35×10^(-6),[H]≤1.5×10^(-6),稳定喂CaSi线速度300~400 m/min,控制中间包[N]≤40×10^(-6),严格连铸保护浇铸工艺,则铸坯中的N含量≤50×10^(-6),钢中TiN夹杂数量显著下降,未发现大尺寸TiN夹杂物。展开更多
This study aims to evaluate the subacute toxic effects of oil under different treatments on marine organism by simulating natural contaminative processes. In this study, 120# （RMD15） fuel oil was selected as the pol...This study aims to evaluate the subacute toxic effects of oil under different treatments on marine organism by simulating natural contaminative processes. In this study, 120# （RMD15） fuel oil was selected as the pollutant and marine medaka （Oryzias melastigma） embryos as the experimental organism. The developmental toxicity of different volume concentrations （0.05%, 0.2%, 1% and 5%） of water-accommodated fractions, biologically-enhanced water-accommodated fractions, and chemically-enhanced water-accommodated fractions on the embryos in different exposure time （8, 15 and 22 d） were compared and the content of relevant polycyclic aromatic hydrocarbons （PAHs） was studied （in dispersion and in vivo）. The subacute toxic effects were assessed in terms of antioxidant activities of enzymes （superoxide dismutase, catalase and glutathione S-transferase） and the blue sac disease （BSD） indexes.The results showed that the BSD indexes of the treatment groups were significantly higher than the respective control groups and showed positive correlations with both concentration and exposure time. The experiments with three antioxidant enzymes indicated that enzymatic activities of the embryos changed dramatically under the oxidation stress of petroleum hydrocarbons, especially after adding the dispersants. With the increase of petroleum hydrocarbon concentration and exposure time, the three enzymes showed different degrees of induction and inhibition effects.展开更多
以小球藻和发光细菌作为受试生物,定量比较120#燃料油在使用消油剂分散前后对两种受试生物的急性毒性效应.结果表明,消油剂本身对两种受试生物的毒性很小,而120#燃料油分散液和乳化液对小球藻急性毒性的96 h EC50分别为5.066 mg/L和2.62...以小球藻和发光细菌作为受试生物,定量比较120#燃料油在使用消油剂分散前后对两种受试生物的急性毒性效应.结果表明,消油剂本身对两种受试生物的毒性很小,而120#燃料油分散液和乳化液对小球藻急性毒性的96 h EC50分别为5.066 mg/L和2.626 mg/L,对发光细菌急性毒性效应的EC50值分别为2.502 mg/L和2.203 mg/L.120#燃料油乳化液的EC50值比分散液显著减小,说明120#燃料油经消油剂处理后,生物毒性有所增强,且发光细菌对120#燃料油相对于小球藻更为敏感.展开更多
基金The National Natural Science Foundation of China under contract No.41276105/D0608
文摘This study aims to evaluate the subacute toxic effects of oil under different treatments on marine organism by simulating natural contaminative processes. In this study, 120# （RMD15） fuel oil was selected as the pollutant and marine medaka （Oryzias melastigma） embryos as the experimental organism. The developmental toxicity of different volume concentrations （0.05%, 0.2%, 1% and 5%） of water-accommodated fractions, biologically-enhanced water-accommodated fractions, and chemically-enhanced water-accommodated fractions on the embryos in different exposure time （8, 15 and 22 d） were compared and the content of relevant polycyclic aromatic hydrocarbons （PAHs） was studied （in dispersion and in vivo）. The subacute toxic effects were assessed in terms of antioxidant activities of enzymes （superoxide dismutase, catalase and glutathione S-transferase） and the blue sac disease （BSD） indexes.The results showed that the BSD indexes of the treatment groups were significantly higher than the respective control groups and showed positive correlations with both concentration and exposure time. The experiments with three antioxidant enzymes indicated that enzymatic activities of the embryos changed dramatically under the oxidation stress of petroleum hydrocarbons, especially after adding the dispersants. With the increase of petroleum hydrocarbon concentration and exposure time, the three enzymes showed different degrees of induction and inhibition effects.
