The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode （ISE） and solidoid balance methods, and t...The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode （ISE） and solidoid balance methods, and the degree of influence on Fluorine pollu- tion generated by coal and clay was analyzed according to the proportion characteristics of coal used by resident households. The results show that the Fluorine release rate of coal is more than 95% during combustion; The Fluorine release rate of clay is more than 99%; The Fluorine release rate of coal mixed with clay is between 56.44% and 96.64%, and the average value is 76.68%. The clay as a binder for fine coal is one important source of Fluorine pollution caused by coal-combustion in Zhaotong, Yunnan Province. When the Fluorine content of coal is less than 80 mg/kg, the F[uodne amount released from clay （in which Fluorine content is more than 530 mg/kg） is more than 50% of the total Fluorine amount released from coal and clay during coal-combustion. The Fluorine amount released from clay （in which Fluorine content is more than 1 000 mg/kg） is more than 70% of total Fluorine amount released from coal and clay during coal-combustion.展开更多
Water soluble upconversion （UC） luminescence hexagonal-phase NaGdF4： yb3＋/Tm3＋ nanoparticles have been successfully synthesized by the hydrothermal method. XRD, SEM, UC photoluminescence spectra and electron para...Water soluble upconversion （UC） luminescence hexagonal-phase NaGdF4： yb3＋/Tm3＋ nanoparticles have been successfully synthesized by the hydrothermal method. XRD, SEM, UC photoluminescence spectra and electron paramagnetic resonance （EPR） spectrum were used to characterize the nanoparticles. The intensity of UC emission region could be controlled through different sodium source and the fluorine source, 6PJ→8S7/2 emission of Gd3＋ is also observed at 310 nm. A broad spectrum with a dominant resonance at g of about 2 was observed by the EPR spectrum of the NaGdF4：Yb3＋/Tm3＋ nanoparticles. The transparent NaGdF4：yb3＋/Tm3＋ solution presented naked eye-visible violet-blue light under the 980 nm LD excitation. The current work paves the way for their potential application in infrared tomography and magnetic resonance imaging （MRI）.展开更多
基金Supported by the National High-Tech Research and Development Program of China(2006AA06Z380)the National Natural Science Fundation of China(40872210)Western Key Fund(90202017)
文摘The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode （ISE） and solidoid balance methods, and the degree of influence on Fluorine pollu- tion generated by coal and clay was analyzed according to the proportion characteristics of coal used by resident households. The results show that the Fluorine release rate of coal is more than 95% during combustion; The Fluorine release rate of clay is more than 99%; The Fluorine release rate of coal mixed with clay is between 56.44% and 96.64%, and the average value is 76.68%. The clay as a binder for fine coal is one important source of Fluorine pollution caused by coal-combustion in Zhaotong, Yunnan Province. When the Fluorine content of coal is less than 80 mg/kg, the F[uodne amount released from clay （in which Fluorine content is more than 530 mg/kg） is more than 50% of the total Fluorine amount released from coal and clay during coal-combustion. The Fluorine amount released from clay （in which Fluorine content is more than 1 000 mg/kg） is more than 70% of total Fluorine amount released from coal and clay during coal-combustion.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （Grant No. 51361009）, Key Program for International S＆T Cooperation Projects of Hainan Province, China （GJXM201103）, Science and Technology Department of Hainan Province, China （Grant No. 090401）, and the Natural Science Foundation of Hainan Province, China （Grant No. 513136）.
文摘Water soluble upconversion （UC） luminescence hexagonal-phase NaGdF4： yb3＋/Tm3＋ nanoparticles have been successfully synthesized by the hydrothermal method. XRD, SEM, UC photoluminescence spectra and electron paramagnetic resonance （EPR） spectrum were used to characterize the nanoparticles. The intensity of UC emission region could be controlled through different sodium source and the fluorine source, 6PJ→8S7/2 emission of Gd3＋ is also observed at 310 nm. A broad spectrum with a dominant resonance at g of about 2 was observed by the EPR spectrum of the NaGdF4：Yb3＋/Tm3＋ nanoparticles. The transparent NaGdF4：yb3＋/Tm3＋ solution presented naked eye-visible violet-blue light under the 980 nm LD excitation. The current work paves the way for their potential application in infrared tomography and magnetic resonance imaging （MRI）.
