The pure bixbyite Mn 2O 3 was prepared by first applying in situ redox precipitation hydrothermal synthesis method under the very mild conditions, and characterized by XRD, TEM, BET and TGA. The effects of alkalinity,...The pure bixbyite Mn 2O 3 was prepared by first applying in situ redox precipitation hydrothermal synthesis method under the very mild conditions, and characterized by XRD, TEM, BET and TGA. The effects of alkalinity, crystallization time and temperature on the product were investigated. The results demonstrated that the alkalinity has an obvious effect on the product whereas the crystallization time and temperature has only a little influence on the product. Too low alkalinity results in no formation of product, and too high alkalinity leads to no formation of pure product with a smaller particle size. Under optimized conditions, the pure bixbyite Mn 2O 3 powder with a better morphology and distribution can be obtained. The average diameter of product is approximate to 80 nm. The normal LiMn 2O 4 spinel used as cathode material can be prepared using as synthesized bixbyite Mn 2O 3 as manganese precursor at 650 ℃ for 2 h by solid state reaction.展开更多
在方差分析中,用字母标记法表示 SSR 测验的结果,较其他方法具有简洁明了的特点。本文利用 BASIC 语言中的字符串截取函数与并置功能,设计编制了用字母标记法进行 SSR 测验的 BAISC 程序,可在 IBM PC、长城0520、PB—700和 PC—1500等...在方差分析中,用字母标记法表示 SSR 测验的结果,较其他方法具有简洁明了的特点。本文利用 BASIC 语言中的字符串截取函数与并置功能,设计编制了用字母标记法进行 SSR 测验的 BAISC 程序,可在 IBM PC、长城0520、PB—700和 PC—1500等微机上运行。展开更多
The effects of galvanic interaction between galena and pyrite on their flotation and electrochemical characters were studied by electrochemical,adsorption,flotation and FTIR techniques,respectively.Electrochemical tes...The effects of galvanic interaction between galena and pyrite on their flotation and electrochemical characters were studied by electrochemical,adsorption,flotation and FTIR techniques,respectively.Electrochemical tests indicate that galena is electrochemically more active than pyrite and serves as an anode in galvanic combination with pyrite.The galvanic current density from a mixture of galena and pyrite is 4 times as high as the self corrosion current density of galena,which indicates that the corrosion rate of galena is accelerated.Adsorption tests show that the adsorption of butyl xanthate on galena surface is enhanced,and affected by a combination of pyrite-galena mixtures and conditioning time.Compared with individual mineral particles,galvanic interaction reduces the floatability difference between galena and pyrite.The flotation recovery of galena decreases while that of pyrite increases when two minerals are mixed together due to the influence of galvanic interaction on the formation of hydrophilic/hydrophobic product.The FTIR results show that the formation of dixanthogen on pyrite surface is depressed due to the galvanic interaction.展开更多
Relativistic configuration interaction calculations for the states of 1s^22s^2, 1s^22s3l （l = s,p,d） and 1s^22p31 （l=s,p,d） configurations of iron are carried out using relativistic configuration interaction （RCI...Relativistic configuration interaction calculations for the states of 1s^22s^2, 1s^22s3l （l = s,p,d） and 1s^22p31 （l=s,p,d） configurations of iron are carried out using relativistic configuration interaction （RCI） and multi-configuration Dirac-Fock （MCDF） method in the active interaction approach. In the present calculation, a large-scale configuration expansion was used in describing the target states. These results are extensively compared with other available calculative and experimental and observed values, the corresponding present results are in good agreement with experimental and observed values, and some differences are found with other available calculative values. Because more relativistic effects are considered than before, the present results should be more accurate and reliable.展开更多
Potassium chloride, Na-pyrophosphate, CuCl2, NH4-oxalate, dithionite-citrate-bicarbonate (DCB) and Na-citrate solutions were employed to extract aluminum (Al) and iron (Fe) sequentially and separately from 15 acidic s...Potassium chloride, Na-pyrophosphate, CuCl2, NH4-oxalate, dithionite-citrate-bicarbonate (DCB) and Na-citrate solutions were employed to extract aluminum (Al) and iron (Fe) sequentially and separately from 15 acidic soils located at the Mangshan Mountains, Hunan Province, China. Many evidences showed that separate pyrophosphate extracted mainly KCI-extractable Al, organo-Al complexes and some inorganic Al compounds, whereas separate CuCl2 extracted KCl-extractable Al and some organo-Al complexes. CuCl2 extracted much less amounts of Al than pyrophosphate did from the soils. Separate oxalate did not extract all KCl-Pyrophosphate- CuCl2 -oxalate sequentially extractable Al and Fe. Also, separate DCB did not extract all KCl- pyrophosphate- CuCl2 -oxalate- DCB sequentially extractable Al. The forms of Al extracted by oxalate and DCB from the soils were majorly noncrystalline. The interlayered materials of 1.4-nm intergrade minerals of the soils were attributed mainly to hydroxy Al polymers.展开更多
文摘The pure bixbyite Mn 2O 3 was prepared by first applying in situ redox precipitation hydrothermal synthesis method under the very mild conditions, and characterized by XRD, TEM, BET and TGA. The effects of alkalinity, crystallization time and temperature on the product were investigated. The results demonstrated that the alkalinity has an obvious effect on the product whereas the crystallization time and temperature has only a little influence on the product. Too low alkalinity results in no formation of product, and too high alkalinity leads to no formation of pure product with a smaller particle size. Under optimized conditions, the pure bixbyite Mn 2O 3 powder with a better morphology and distribution can be obtained. The average diameter of product is approximate to 80 nm. The normal LiMn 2O 4 spinel used as cathode material can be prepared using as synthesized bixbyite Mn 2O 3 as manganese precursor at 650 ℃ for 2 h by solid state reaction.
基金Project(51274255)supported by the National Natural Science Foundation of ChinaProject supported by the Co-innovation Center for Clean and Efficient Utilization of Strategic Metal Mineral Resources,China
文摘The effects of galvanic interaction between galena and pyrite on their flotation and electrochemical characters were studied by electrochemical,adsorption,flotation and FTIR techniques,respectively.Electrochemical tests indicate that galena is electrochemically more active than pyrite and serves as an anode in galvanic combination with pyrite.The galvanic current density from a mixture of galena and pyrite is 4 times as high as the self corrosion current density of galena,which indicates that the corrosion rate of galena is accelerated.Adsorption tests show that the adsorption of butyl xanthate on galena surface is enhanced,and affected by a combination of pyrite-galena mixtures and conditioning time.Compared with individual mineral particles,galvanic interaction reduces the floatability difference between galena and pyrite.The flotation recovery of galena decreases while that of pyrite increases when two minerals are mixed together due to the influence of galvanic interaction on the formation of hydrophilic/hydrophobic product.The FTIR results show that the formation of dixanthogen on pyrite surface is depressed due to the galvanic interaction.
基金supported by the Leshan Teachers College under Grant No.206113
文摘Relativistic configuration interaction calculations for the states of 1s^22s^2, 1s^22s3l （l = s,p,d） and 1s^22p31 （l=s,p,d） configurations of iron are carried out using relativistic configuration interaction （RCI） and multi-configuration Dirac-Fock （MCDF） method in the active interaction approach. In the present calculation, a large-scale configuration expansion was used in describing the target states. These results are extensively compared with other available calculative and experimental and observed values, the corresponding present results are in good agreement with experimental and observed values, and some differences are found with other available calculative values. Because more relativistic effects are considered than before, the present results should be more accurate and reliable.
文摘Potassium chloride, Na-pyrophosphate, CuCl2, NH4-oxalate, dithionite-citrate-bicarbonate (DCB) and Na-citrate solutions were employed to extract aluminum (Al) and iron (Fe) sequentially and separately from 15 acidic soils located at the Mangshan Mountains, Hunan Province, China. Many evidences showed that separate pyrophosphate extracted mainly KCI-extractable Al, organo-Al complexes and some inorganic Al compounds, whereas separate CuCl2 extracted KCl-extractable Al and some organo-Al complexes. CuCl2 extracted much less amounts of Al than pyrophosphate did from the soils. Separate oxalate did not extract all KCl-Pyrophosphate- CuCl2 -oxalate sequentially extractable Al and Fe. Also, separate DCB did not extract all KCl- pyrophosphate- CuCl2 -oxalate- DCB sequentially extractable Al. The forms of Al extracted by oxalate and DCB from the soils were majorly noncrystalline. The interlayered materials of 1.4-nm intergrade minerals of the soils were attributed mainly to hydroxy Al polymers.
