Recent work on the Panzhihua intrusion has produced two separate models for the crystallisation of the intrusion：（1） low-Ti,high CaO and low H2O（0.5 wt.%） parent magma（equivalent to Emeishan low-Ti basalt） at F...Recent work on the Panzhihua intrusion has produced two separate models for the crystallisation of the intrusion：（1） low-Ti,high CaO and low H2O（0.5 wt.%） parent magma（equivalent to Emeishan low-Ti basalt） at FMQ;and（2） high-Ti,low CaO and higher H2O（＆gt;1.5 wt.%） parent magma（equivalent to Emeishan high-Ti basalt） at FMQ ＋ 1.5.Modelling of these parent magma compositions produces significantly different results. We present here detailed f（O2） and H2O modelling for average compositions of both Emeishan high-Ti and low-Ti ferrobasalts in order to constrain the effects on crystallisation sequences for Emeishan ultra-mafic -mafic layered intrusions.Modelling is consistent with numerous experimental studies on ferro-basaltic magmas from other localities（e.g.Skaergaard intrusion）.Modelling is compared with the geology of the Panzhihua intrusion in order to constrain the crystallisation of the gabbroic rocks and the Fe-Ti oxides ore layers.We suggest that the gabbroic rocks at the Panzhihua intrusion can be best explained by crystallisation from a parent magma similar to that of the high-Ti Emeishan basalt at moderate H2O contents（0.5-1 wt.%） but at the lower end of TiO2 content for typical high-Ti basalts（2.5 wt.%TiO2）. Distinct silicate disequilibrium textures in the Fe-Ti oxide ore layers suggest that an influx of H2O may be responsible for changing the crystallisation path.An increase in H2O during crystallisation of gabbroic rocks will result in the depression of silicate liquidus temperatures and resultant disequilibrium with the liquid.Continued cooling of the magma with high H2O then results in precipitation of Mt-Uv alone. The H2O content of parent magmas for mafic layered intrusions associated with the ELIP is an important variable.H2O alters the crystallisation sequence of the basaltic magmas so that at high H2O and f（O2） Mt -Uv crystallises earlier than plagioclase and clinopyroxene.Furthermore,the addition of H2O to an anhydrous magma can explain silicate disequilibrium texture observed in the Fe-Ti oxide ore layers.展开更多
采用溶胶-凝胶法制备Ti/Sn O_2-F电极,进行全氟辛酸(PFOA)电氧化降解的研究,实验考察了F替代Sb掺杂、电流密度、初始pH值和支持电解质对PFOA降解效率的影响。结果表明,当F替代Sb掺杂Sn O_2,电流密度为20 m A/cm^2,初始pH值3.7,支持电解...采用溶胶-凝胶法制备Ti/Sn O_2-F电极,进行全氟辛酸(PFOA)电氧化降解的研究,实验考察了F替代Sb掺杂、电流密度、初始pH值和支持电解质对PFOA降解效率的影响。结果表明,当F替代Sb掺杂Sn O_2,电流密度为20 m A/cm^2,初始pH值3.7,支持电解质为NaClO_4时,电解30 min后PFOA的降解率达98%。采用液相色谱-质谱联用(HPLC-MS/MS)和离子色谱(IC)对PFOA降解产物进行分析,解析了PFOA电氧化降解的反应机理。展开更多
基金funding through South African National Science Foundation(NRF)Grant SA/China Project 67220 to SP and Mei-Fu ZhouGH also acknowledges the support of a doctoral fellowship from the NRF for 2011-2012
文摘Recent work on the Panzhihua intrusion has produced two separate models for the crystallisation of the intrusion：（1） low-Ti,high CaO and low H2O（0.5 wt.%） parent magma（equivalent to Emeishan low-Ti basalt） at FMQ;and（2） high-Ti,low CaO and higher H2O（＆gt;1.5 wt.%） parent magma（equivalent to Emeishan high-Ti basalt） at FMQ ＋ 1.5.Modelling of these parent magma compositions produces significantly different results. We present here detailed f（O2） and H2O modelling for average compositions of both Emeishan high-Ti and low-Ti ferrobasalts in order to constrain the effects on crystallisation sequences for Emeishan ultra-mafic -mafic layered intrusions.Modelling is consistent with numerous experimental studies on ferro-basaltic magmas from other localities（e.g.Skaergaard intrusion）.Modelling is compared with the geology of the Panzhihua intrusion in order to constrain the crystallisation of the gabbroic rocks and the Fe-Ti oxides ore layers.We suggest that the gabbroic rocks at the Panzhihua intrusion can be best explained by crystallisation from a parent magma similar to that of the high-Ti Emeishan basalt at moderate H2O contents（0.5-1 wt.%） but at the lower end of TiO2 content for typical high-Ti basalts（2.5 wt.%TiO2）. Distinct silicate disequilibrium textures in the Fe-Ti oxide ore layers suggest that an influx of H2O may be responsible for changing the crystallisation path.An increase in H2O during crystallisation of gabbroic rocks will result in the depression of silicate liquidus temperatures and resultant disequilibrium with the liquid.Continued cooling of the magma with high H2O then results in precipitation of Mt-Uv alone. The H2O content of parent magmas for mafic layered intrusions associated with the ELIP is an important variable.H2O alters the crystallisation sequence of the basaltic magmas so that at high H2O and f（O2） Mt -Uv crystallises earlier than plagioclase and clinopyroxene.Furthermore,the addition of H2O to an anhydrous magma can explain silicate disequilibrium texture observed in the Fe-Ti oxide ore layers.
