[Objective]This paper was to synthesize the intermediate diethyl 5-ethylpyridine-2,3-dicarboxylate of imazethapyr using 5-ethyl-2,3-pyridinedicarboxylic acid as the raw material.[Method]Diethyl 5-ethylpyridine-2,3-dic...[Objective]This paper was to synthesize the intermediate diethyl 5-ethylpyridine-2,3-dicarboxylate of imazethapyr using 5-ethyl-2,3-pyridinedicarboxylic acid as the raw material.[Method]Diethyl 5-ethylpyridine-2,3-dicarboxylate was successfully synthesized via direct esterification and indirect esterification.[Result]The structure of intermediate was confirmed by LC and1 H NMR.[Conclusion]The intermediate yield of the two methods was both above 89%.Imazethapyr was prepared from the intermediate and the purity reached 99%.展开更多
Nano 3C-SiC@multilayer graphene oxide(NS@MGO)heterostructure was in situ prepared by carbothermal reduction of pyrolyzed precursor composed of highly dispersed cured phenolic resin and silicon dioxide derived from tet...Nano 3C-SiC@multilayer graphene oxide(NS@MGO)heterostructure was in situ prepared by carbothermal reduction of pyrolyzed precursor composed of highly dispersed cured phenolic resin and silicon dioxide derived from tetraethyl orthosilicate.The heterojunction interface,number of layers of MGO,and defect content in graphene are the three most important factors for promoting photocatalytic activity.Direct contact between 3C-SiC nanograins and MGO layers facilitates the photogenerated electrons to migrate across the heterojunction interface and avoid the formation of SiO_(2) nanolayers on the surface of SiC nanograins.The number of MGO layers is supposed to be less than ten instead of over-thick MGO.The concentrations of oxygenated components,considered the defect contents,decrease with the increase of sintering temperature for NS@MGO 0.175-T-150,and relative carbon content in the multilayer graphene increases.According to the heterostructures,properties,and photocatalytic reaction performance of the NS@MGO materials,the highest photocatalytic kinetic rate constant of 0.00891/min for NS@MGO 0.175-1500-150 shows that the significant enhancement in photocatalytic degradation activity under visible light(>420 nm)irradiation is ascribed to the advantageous synergistic effects between the nano 3C-SiC particles and the direct contact multilayer graphene oxide with appropriate layers and sufficient oxygen content of 3.51%(atomic fraction)in MGO.展开更多
文摘[Objective]This paper was to synthesize the intermediate diethyl 5-ethylpyridine-2,3-dicarboxylate of imazethapyr using 5-ethyl-2,3-pyridinedicarboxylic acid as the raw material.[Method]Diethyl 5-ethylpyridine-2,3-dicarboxylate was successfully synthesized via direct esterification and indirect esterification.[Result]The structure of intermediate was confirmed by LC and1 H NMR.[Conclusion]The intermediate yield of the two methods was both above 89%.Imazethapyr was prepared from the intermediate and the purity reached 99%.
基金This work was supported by the National Key Research and Development Program of China(No.2021YFB3801301)the Shenyang National Laboratory for Materials Science(SYNL,China)Program for Youth Talent(No.L2022F39).
文摘Nano 3C-SiC@multilayer graphene oxide(NS@MGO)heterostructure was in situ prepared by carbothermal reduction of pyrolyzed precursor composed of highly dispersed cured phenolic resin and silicon dioxide derived from tetraethyl orthosilicate.The heterojunction interface,number of layers of MGO,and defect content in graphene are the three most important factors for promoting photocatalytic activity.Direct contact between 3C-SiC nanograins and MGO layers facilitates the photogenerated electrons to migrate across the heterojunction interface and avoid the formation of SiO_(2) nanolayers on the surface of SiC nanograins.The number of MGO layers is supposed to be less than ten instead of over-thick MGO.The concentrations of oxygenated components,considered the defect contents,decrease with the increase of sintering temperature for NS@MGO 0.175-T-150,and relative carbon content in the multilayer graphene increases.According to the heterostructures,properties,and photocatalytic reaction performance of the NS@MGO materials,the highest photocatalytic kinetic rate constant of 0.00891/min for NS@MGO 0.175-1500-150 shows that the significant enhancement in photocatalytic degradation activity under visible light(>420 nm)irradiation is ascribed to the advantageous synergistic effects between the nano 3C-SiC particles and the direct contact multilayer graphene oxide with appropriate layers and sufficient oxygen content of 3.51%(atomic fraction)in MGO.
