In an alkaline 2-propanol solution with 5,10,15,20-tetra(4-methoxyl phenyl) porphyrin iron chloride(TOMPPFeCl) as a catalyst and oxygen as a cheap green oxidant, 2-naphthol was conversed to 2-hydroxy-\{1,4-naphthoquin...In an alkaline 2-propanol solution with 5,10,15,20-tetra(4-methoxyl phenyl) porphyrin iron chloride(TOMPPFeCl) as a catalyst and oxygen as a cheap green oxidant, 2-naphthol was conversed to 2-hydroxy-\{1,4-naphthoquinone(HNQ)\} with a yield of 62.17% and a selectivity of 100%, and the conversion number of TMOPPFeCl catalyst was 8.32/min. The catalytic oxidation products were characterized by means of UV-Vis, IR, GC-MS, ~ 1H NMR and melting point determination. In this catalytic oxidation, the catalytic activity of TMOPPFeCl was researched in detail and the reacting conditions were optimized. A possible reaction mechanism is summarized based on in situ EPR determination.展开更多
In an alkali-methanol solution, both 1- and 2-naphthol can be converted into 2-hydroxy-1,4-naphthoquinone(HNQ) with selectivity more than 95% by H_2O_2 over metalloporphyrin catalyst. The UV-Vis spectra indicate that ...In an alkali-methanol solution, both 1- and 2-naphthol can be converted into 2-hydroxy-1,4-naphthoquinone(HNQ) with selectivity more than 95% by H_2O_2 over metalloporphyrin catalyst. The UV-Vis spectra indicate that a high valence oxygen-ferreous porphyrin intermediate has been produced by addition of an aqueous solution of H_2O_2 into the catalytic system. This intermediate formation rate is influenced by the concentrations of low valence ferrous porphyrin, H_2O_2, and NaOH existing in the system. With the aid of the UV-Vis spectrum varieties, the rate equations and formation rate constants of the intermediate at different temperatures can be determined by changing the original concentration of each reactant. The formation activation energy of this intermediate was also determined by changing temperature.展开更多
Objective To find out a proper way to detect green fluorescent protein (GFP). Methods Kidneys, livers and femurs from GFP transgenic mice and C57BL/6J wild type mice were employed for in vivo study. The samples were d...Objective To find out a proper way to detect green fluorescent protein (GFP). Methods Kidneys, livers and femurs from GFP transgenic mice and C57BL/6J wild type mice were employed for in vivo study. The samples were dehydrated with alcohol and acetone individually before embedding, then frozen, paraffin and resin sections were made for the detection of GFP. C3 P12 cells which derived from calvaria bone cells of GFP transgenic mouse were used for the detection of GFP in vitro. Cells were exposed to alcohol, acetone and PBS after paraformaldehyde fixation. Laser scanning microscopy was employed for GFP detection. Results In frozen sections, both kidney and liver samples which exposed to 4% buffered paraformaldehyde fixation had strong GFP signals, while GFP signal disappeared completely in fresh frozen sections without fixation. Much stronger GFP intensity was found in acetone treated samples than in alcohol treated paraffin sections, but without apparent difference in GFP intensity in acetone and alcohol treated resin samples. Acetone and alcohol made no difference in fixed C3 cells in different time courses. Conclusion Acetone treated paraffin sections are preferable for GFP detection.展开更多
文摘In an alkaline 2-propanol solution with 5,10,15,20-tetra(4-methoxyl phenyl) porphyrin iron chloride(TOMPPFeCl) as a catalyst and oxygen as a cheap green oxidant, 2-naphthol was conversed to 2-hydroxy-\{1,4-naphthoquinone(HNQ)\} with a yield of 62.17% and a selectivity of 100%, and the conversion number of TMOPPFeCl catalyst was 8.32/min. The catalytic oxidation products were characterized by means of UV-Vis, IR, GC-MS, ~ 1H NMR and melting point determination. In this catalytic oxidation, the catalytic activity of TMOPPFeCl was researched in detail and the reacting conditions were optimized. A possible reaction mechanism is summarized based on in situ EPR determination.
文摘In an alkali-methanol solution, both 1- and 2-naphthol can be converted into 2-hydroxy-1,4-naphthoquinone(HNQ) with selectivity more than 95% by H_2O_2 over metalloporphyrin catalyst. The UV-Vis spectra indicate that a high valence oxygen-ferreous porphyrin intermediate has been produced by addition of an aqueous solution of H_2O_2 into the catalytic system. This intermediate formation rate is influenced by the concentrations of low valence ferrous porphyrin, H_2O_2, and NaOH existing in the system. With the aid of the UV-Vis spectrum varieties, the rate equations and formation rate constants of the intermediate at different temperatures can be determined by changing the original concentration of each reactant. The formation activation energy of this intermediate was also determined by changing temperature.
文摘Objective To find out a proper way to detect green fluorescent protein (GFP). Methods Kidneys, livers and femurs from GFP transgenic mice and C57BL/6J wild type mice were employed for in vivo study. The samples were dehydrated with alcohol and acetone individually before embedding, then frozen, paraffin and resin sections were made for the detection of GFP. C3 P12 cells which derived from calvaria bone cells of GFP transgenic mouse were used for the detection of GFP in vitro. Cells were exposed to alcohol, acetone and PBS after paraformaldehyde fixation. Laser scanning microscopy was employed for GFP detection. Results In frozen sections, both kidney and liver samples which exposed to 4% buffered paraformaldehyde fixation had strong GFP signals, while GFP signal disappeared completely in fresh frozen sections without fixation. Much stronger GFP intensity was found in acetone treated samples than in alcohol treated paraffin sections, but without apparent difference in GFP intensity in acetone and alcohol treated resin samples. Acetone and alcohol made no difference in fixed C3 cells in different time courses. Conclusion Acetone treated paraffin sections are preferable for GFP detection.
