The Ti-supported lead dioxide electrode(Ti/PdO2) consisted of a Sb2O3/SnO2 semiconductive interlayer and electrodeposited PbO2 films was prepared. The optimum ratio of Sb2O3 to SnO2 was 15%25%. Addition of NaF(0.40...The Ti-supported lead dioxide electrode(Ti/PdO2) consisted of a Sb2O3/SnO2 semiconductive interlayer and electrodeposited PbO2 films was prepared. The optimum ratio of Sb2O3 to SnO2 was 15%25%. Addition of NaF(0.40 g/L) in electroplating solution could decrease the rate of PbO2 deposition, which resulted in the formation of small crystal particles and compact PbO2 films. XRD study showed the β-form crystal of electrode. The electrode was tested in synthesis of 4-picoline acid by electro-oxidation of 4-picoline, showing good electroconductivity and stable life.展开更多
Amphichoterpenoids A-C(1-3),unprecedented picoline-derived meroterpenoids possessing a pyrano[3,2-c]pyridinyl-g-pyranone scaffold,were characterized from the ascidian-derived fungus Amphichorda felina SYSU-MS7908.Thei...Amphichoterpenoids A-C(1-3),unprecedented picoline-derived meroterpenoids possessing a pyrano[3,2-c]pyridinyl-g-pyranone scaffold,were characterized from the ascidian-derived fungus Amphichorda felina SYSU-MS7908.Their structures were elucidated by spectroscopic methods,X-ray diffraction and electronic circular dichroism(ECD)calculations.A plausible biosynthetic pathway was proposed.The isolated compounds displayed moderate inhibitory activity against acetylcholinesterase with 50%inhibiting concentration(IC_(50))values of 18.8-53.2 mmol/L.展开更多
利用2277热活性检测仪的流动测量系统测定了298.15K时,乙酰胺与三种甲基吡啶异构体在水溶液中混合过程焓变以及各自的稀释焓,根据M cM illan-M ayer理论关联得到了各级焓作用系数。三种异构体分子亲水和疏水基团的数目是相等的,只是位...利用2277热活性检测仪的流动测量系统测定了298.15K时,乙酰胺与三种甲基吡啶异构体在水溶液中混合过程焓变以及各自的稀释焓,根据M cM illan-M ayer理论关联得到了各级焓作用系数。三种异构体分子亲水和疏水基团的数目是相等的,只是位置不同,但溶质-溶质相互作用理论及基团贡献法理论都无法解释空间异构所造成的热效应的差异。而通过理论计算分别得到其最稳定的氢键络合物和结合能,通过对络合物空间构型及键角、键长的分析很好地解释了热效应的不同。展开更多
文摘The Ti-supported lead dioxide electrode(Ti/PdO2) consisted of a Sb2O3/SnO2 semiconductive interlayer and electrodeposited PbO2 films was prepared. The optimum ratio of Sb2O3 to SnO2 was 15%25%. Addition of NaF(0.40 g/L) in electroplating solution could decrease the rate of PbO2 deposition, which resulted in the formation of small crystal particles and compact PbO2 films. XRD study showed the β-form crystal of electrode. The electrode was tested in synthesis of 4-picoline acid by electro-oxidation of 4-picoline, showing good electroconductivity and stable life.
基金the National Natural Science Foundation of China(No.41806155)the Guangdong MEPP Fund(No.GDOE(2019)A21)+2 种基金the National Key R&D Program of China(No.2019YFC0312501)the Natural Science Foundation of Guangdong Province(No.2018A030310304)the Key-Area Research and Development Program of Guangdong Province(No.2020B1111030005)for generous support。
文摘Amphichoterpenoids A-C(1-3),unprecedented picoline-derived meroterpenoids possessing a pyrano[3,2-c]pyridinyl-g-pyranone scaffold,were characterized from the ascidian-derived fungus Amphichorda felina SYSU-MS7908.Their structures were elucidated by spectroscopic methods,X-ray diffraction and electronic circular dichroism(ECD)calculations.A plausible biosynthetic pathway was proposed.The isolated compounds displayed moderate inhibitory activity against acetylcholinesterase with 50%inhibiting concentration(IC_(50))values of 18.8-53.2 mmol/L.
文摘利用2277热活性检测仪的流动测量系统测定了298.15K时,乙酰胺与三种甲基吡啶异构体在水溶液中混合过程焓变以及各自的稀释焓,根据M cM illan-M ayer理论关联得到了各级焓作用系数。三种异构体分子亲水和疏水基团的数目是相等的,只是位置不同,但溶质-溶质相互作用理论及基团贡献法理论都无法解释空间异构所造成的热效应的差异。而通过理论计算分别得到其最稳定的氢键络合物和结合能,通过对络合物空间构型及键角、键长的分析很好地解释了热效应的不同。