Three special types of xenoliths have recently been found in an aegirine-augite syenite porphyry in Liuhe, Yunnan, China. Petrographical, petrochemical, electron microprobe, and scanning electron microscopy studies in...Three special types of xenoliths have recently been found in an aegirine-augite syenite porphyry in Liuhe, Yunnan, China. Petrographical, petrochemical, electron microprobe, and scanning electron microscopy studies indicate that pure calcite xenocrysts and quartz-bearing topaz pegmatite xenoliths result from the degassing of mantle fluids during their migration, and that black microcrystalline iron-rich silicate-melt xenoliths are the product of the extraction of mantle fluids accompanying degassing and are composed dominantly of quartz, chlorite, and iron-rich columnar and sheet silicate minerals with characteristic minerals, such as native iron, apatite, and zircon. According to the bulk-rock chemical and mineral compositions and crystallization states, the microcrystalline melt xenoliths are not the product of conventional magmatism, and especially the existence of native iron further proves that the xenoliths were mantle fluid materials under reduction or anoxic conditions. The study of the special xenoliths furnishes an important deep-process geochemical background of polymetallic mineralization in different rocks and strata in the study area.展开更多
The effect of cadmium, aluminum, and sulphate ions on struvite precipitation kinetics and morphology of solids obtained was investigated in this study. Thus, these ions were introduced as additives in solution where s...The effect of cadmium, aluminum, and sulphate ions on struvite precipitation kinetics and morphology of solids obtained was investigated in this study. Thus, these ions were introduced as additives in solution where struvite precipitation was achieved. The main results obtained showed that the Cd2+ ions cause the probable co-formation, with struvite, of an amorphous phase observed from Cd2+ concentration of 10 mg/L;the addition of aluminum ions in the solution does not affect the nature of the crystalline phase, identified as struvite. However, these ions cause the formation of agglomerates of larger and larger as the concentration rises. Moreover, their increasing improved significantly the yield of phosphates removal;although the sulfate ions have no effect on the nature of the precipitated phase identified as struvite, independently of molar ratio studied, they affect the thermal decomposition of struvite. This latter is done in a single step by increasing the concentration of these ions for the SO42−/PO43−molar ratio of 8.展开更多
基金supported by National Natural Science Foundation of China grant 40473027 and 40773031Foundation of Open Subjects of the State Key Laboratory of Geological Processes and Mineral Resources of the China University of Geosciences grant GPMR0509 and GPMR200705the Project of the State Key(Preparation Support)Disciplines of Mineralogy,Petrology and Mineral Deposit Geology of Sichuan Province.
文摘Three special types of xenoliths have recently been found in an aegirine-augite syenite porphyry in Liuhe, Yunnan, China. Petrographical, petrochemical, electron microprobe, and scanning electron microscopy studies indicate that pure calcite xenocrysts and quartz-bearing topaz pegmatite xenoliths result from the degassing of mantle fluids during their migration, and that black microcrystalline iron-rich silicate-melt xenoliths are the product of the extraction of mantle fluids accompanying degassing and are composed dominantly of quartz, chlorite, and iron-rich columnar and sheet silicate minerals with characteristic minerals, such as native iron, apatite, and zircon. According to the bulk-rock chemical and mineral compositions and crystallization states, the microcrystalline melt xenoliths are not the product of conventional magmatism, and especially the existence of native iron further proves that the xenoliths were mantle fluid materials under reduction or anoxic conditions. The study of the special xenoliths furnishes an important deep-process geochemical background of polymetallic mineralization in different rocks and strata in the study area.
文摘The effect of cadmium, aluminum, and sulphate ions on struvite precipitation kinetics and morphology of solids obtained was investigated in this study. Thus, these ions were introduced as additives in solution where struvite precipitation was achieved. The main results obtained showed that the Cd2+ ions cause the probable co-formation, with struvite, of an amorphous phase observed from Cd2+ concentration of 10 mg/L;the addition of aluminum ions in the solution does not affect the nature of the crystalline phase, identified as struvite. However, these ions cause the formation of agglomerates of larger and larger as the concentration rises. Moreover, their increasing improved significantly the yield of phosphates removal;although the sulfate ions have no effect on the nature of the precipitated phase identified as struvite, independently of molar ratio studied, they affect the thermal decomposition of struvite. This latter is done in a single step by increasing the concentration of these ions for the SO42−/PO43−molar ratio of 8.
