Influence of CaO on thermal decomposition of REFCO3 was studied. The results showed that CaO did not affect significantly the decomposition ratio of REFCO3. The XRD experiment showed that there was a great deal of CaF...Influence of CaO on thermal decomposition of REFCO3 was studied. The results showed that CaO did not affect significantly the decomposition ratio of REFCO3. The XRD experiment showed that there was a great deal of CaF2 in the masting production, the gas chromatographic analysis on the gas of REFCO3 decomposed, and the 70% content of fluorine in the gas of REFCO3 added 15% CaO was reduced. CaO could absorb the fluorine from the decomposition of REFCO3, and the environmental pollution of the fluorine was greatly alleviated,展开更多
Fluorine content of tea leaves in mountainy tea gardens in Zhejiang Province and the influence factors were measured in 68 random plots,and a soil sample,a Spring’s tea sample and an Autumn’s tea sample were collect...Fluorine content of tea leaves in mountainy tea gardens in Zhejiang Province and the influence factors were measured in 68 random plots,and a soil sample,a Spring’s tea sample and an Autumn’s tea sample were collected in each plot.The results showed that 99.3% of the total tea samples met the requirement of NY659-2003 in respect of fluorine,and the mean content of all 136 samples was much lower than the average fluorine level of Chinese green tea.The leaf fluorine contents of in the Spring and Autumn tea were respectively(60.28±47.00)and(61.43±31.19)mg·kg-1 and there was no statistical difference between them.Regression analyses on the fluorine contents of tea and soil indicated that the fluorine content in soil significantly affect the fluorine content in Spring’s tea but not that in Autumn’s tea.The fluorine content of tea leaves was not different in relation to the altitude of tea gardens.However,the fluorine content was significantly(P<0.01)different among various varieties of tea plants(Camellia sinensis),which suggested the capabilities for them to absorb and accumulate fluorine from their environment were different.展开更多
基金Project supported by the National Natural Science Foundation of China (50574031)
文摘Influence of CaO on thermal decomposition of REFCO3 was studied. The results showed that CaO did not affect significantly the decomposition ratio of REFCO3. The XRD experiment showed that there was a great deal of CaF2 in the masting production, the gas chromatographic analysis on the gas of REFCO3 decomposed, and the 70% content of fluorine in the gas of REFCO3 added 15% CaO was reduced. CaO could absorb the fluorine from the decomposition of REFCO3, and the environmental pollution of the fluorine was greatly alleviated,
文摘Fluorine content of tea leaves in mountainy tea gardens in Zhejiang Province and the influence factors were measured in 68 random plots,and a soil sample,a Spring’s tea sample and an Autumn’s tea sample were collected in each plot.The results showed that 99.3% of the total tea samples met the requirement of NY659-2003 in respect of fluorine,and the mean content of all 136 samples was much lower than the average fluorine level of Chinese green tea.The leaf fluorine contents of in the Spring and Autumn tea were respectively(60.28±47.00)and(61.43±31.19)mg·kg-1 and there was no statistical difference between them.Regression analyses on the fluorine contents of tea and soil indicated that the fluorine content in soil significantly affect the fluorine content in Spring’s tea but not that in Autumn’s tea.The fluorine content of tea leaves was not different in relation to the altitude of tea gardens.However,the fluorine content was significantly(P<0.01)different among various varieties of tea plants(Camellia sinensis),which suggested the capabilities for them to absorb and accumulate fluorine from their environment were different.
