Aim To study isolation and purification of Gonyautoxins from two differentstrains of Alexandrium minutum Halim. Methods Ethanol extracts of the two culture strains ofAlexandrium minutum Halim were fractionated by gel ...Aim To study isolation and purification of Gonyautoxins from two differentstrains of Alexandrium minutum Halim. Methods Ethanol extracts of the two culture strains ofAlexandrium minutum Halim were fractionated by gel filtration and ion exchange chromatography toobtain gonyautoxins. The toxin profiles were tested by HPLC method. Results Both strains containgonyautoxin-1, gonyautoxin-2, gonyautoxin-3 and gonyautoxin-4. The total gonyautoxin content ofAmtk4 strain is almost 10 times higher than that of Amtk2 strain. Conclusion Alexandrium minutumHalim Amtk4 strain is suitable for the preparation of Gonyautoxins.展开更多
In this paper,after discussing the prime implication filter of lattice implication algebra,we introduced the concept of prime space of lattice implication algebra,in which we analysised its topological property and di...In this paper,after discussing the prime implication filter of lattice implication algebra,we introduced the concept of prime space of lattice implication algebra,in which we analysised its topological property and discussed the relation between the category of topological space and the category of lattice implication algebras.展开更多
A new method by liquid-liquid-liquid three phase system, consisting of acidified primary amine N1923 (abbreviated as A-N1923), poly(ethylene glycol) (PEG) and (NH4)2S04 aqueous solution, was suggested for the ...A new method by liquid-liquid-liquid three phase system, consisting of acidified primary amine N1923 (abbreviated as A-N1923), poly(ethylene glycol) (PEG) and (NH4)2S04 aqueous solution, was suggested for the separation and simultaneous extraction of Ⅴ(Ⅴ) and Cr(Ⅵ) from the acidic leach solutions of high- chromium vanadium-titanium magnetite. Experimental results indicated that Ⅴ(Ⅴ) and Cr(Ⅵ) could be selectively enriched into the A-N1923 organic top phase and PEG-rich middle phase, respectively, while AI(Ⅲ) and other co-existing impurity ions, such as Si(Ⅳ), Fe(Ⅲ), Ti(Ⅳ), Mg(Ⅱ) and Ca(Ⅱ) in acidic leach solutions, could be enriched in the (NH4)2SO4 bottom aqueous phase. During the process for extraction and separation of Ⅴ(Ⅴ) and Cr(Ⅵ), almost all of impurity ions could be removed. The separation factors between Ⅴ (Ⅴ) and Cr(Ⅵ) could reach 630 and 908, respectively in the organic top phase and PEG middle phase, and yields of recovered Ⅴ(Ⅴ) and Cr(Ⅵ) in the top phase and middle phase respectively were all above 90%. Various effects including aqueous pH, A-N1923 concentration, PEG added amount and (NH4)2SO4 concentration on three-phase partitioning of Ⅴ(Ⅴ) and Cr(Ⅵ) were discussed. It was found that the partition of Cr(Ⅵ) into the PEG-rich middle phase was driven by hydrophobic interaction, while extraction of Ⅴ(Ⅴ) by A-N1923 resulted of anion exchange between NO; and H2V10O4-28. Stripping of Ⅴ(Ⅴ) and Cr(Ⅵ) from the top organic phase and the middle PEG-rich phase were achieved by mixing respectively with NANO3 aqueous solutions and NaOH-(NH4)2SO4 solutions. The present work highlights a new approach for the extraction and purification of V and Cr from the complex multi-metal co-existing acidic leach solutions of high-chromium vanadium-titanium magnetite.展开更多
文摘Aim To study isolation and purification of Gonyautoxins from two differentstrains of Alexandrium minutum Halim. Methods Ethanol extracts of the two culture strains ofAlexandrium minutum Halim were fractionated by gel filtration and ion exchange chromatography toobtain gonyautoxins. The toxin profiles were tested by HPLC method. Results Both strains containgonyautoxin-1, gonyautoxin-2, gonyautoxin-3 and gonyautoxin-4. The total gonyautoxin content ofAmtk4 strain is almost 10 times higher than that of Amtk2 strain. Conclusion Alexandrium minutumHalim Amtk4 strain is suitable for the preparation of Gonyautoxins.
文摘In this paper,after discussing the prime implication filter of lattice implication algebra,we introduced the concept of prime space of lattice implication algebra,in which we analysised its topological property and discussed the relation between the category of topological space and the category of lattice implication algebras.
基金Supported by the National Basic Research and Development Program of China(973ProgramNo.2013CB632602)the National Natural Science Foundation of China(Nos.51574213,51074150)
文摘A new method by liquid-liquid-liquid three phase system, consisting of acidified primary amine N1923 (abbreviated as A-N1923), poly(ethylene glycol) (PEG) and (NH4)2S04 aqueous solution, was suggested for the separation and simultaneous extraction of Ⅴ(Ⅴ) and Cr(Ⅵ) from the acidic leach solutions of high- chromium vanadium-titanium magnetite. Experimental results indicated that Ⅴ(Ⅴ) and Cr(Ⅵ) could be selectively enriched into the A-N1923 organic top phase and PEG-rich middle phase, respectively, while AI(Ⅲ) and other co-existing impurity ions, such as Si(Ⅳ), Fe(Ⅲ), Ti(Ⅳ), Mg(Ⅱ) and Ca(Ⅱ) in acidic leach solutions, could be enriched in the (NH4)2SO4 bottom aqueous phase. During the process for extraction and separation of Ⅴ(Ⅴ) and Cr(Ⅵ), almost all of impurity ions could be removed. The separation factors between Ⅴ (Ⅴ) and Cr(Ⅵ) could reach 630 and 908, respectively in the organic top phase and PEG middle phase, and yields of recovered Ⅴ(Ⅴ) and Cr(Ⅵ) in the top phase and middle phase respectively were all above 90%. Various effects including aqueous pH, A-N1923 concentration, PEG added amount and (NH4)2SO4 concentration on three-phase partitioning of Ⅴ(Ⅴ) and Cr(Ⅵ) were discussed. It was found that the partition of Cr(Ⅵ) into the PEG-rich middle phase was driven by hydrophobic interaction, while extraction of Ⅴ(Ⅴ) by A-N1923 resulted of anion exchange between NO; and H2V10O4-28. Stripping of Ⅴ(Ⅴ) and Cr(Ⅵ) from the top organic phase and the middle PEG-rich phase were achieved by mixing respectively with NANO3 aqueous solutions and NaOH-(NH4)2SO4 solutions. The present work highlights a new approach for the extraction and purification of V and Cr from the complex multi-metal co-existing acidic leach solutions of high-chromium vanadium-titanium magnetite.