3-hydroxyflavone (3-HF) is an organic molecule with an excited-stated intramolecular proton transfer (ESIPT) effect. All-optical switchings and beam deflections of 3-HF in three kinds of solvents (cyclohexane, et...3-hydroxyflavone (3-HF) is an organic molecule with an excited-stated intramolecular proton transfer (ESIPT) effect. All-optical switchings and beam deflections of 3-HF in three kinds of solvents (cyclohexane, ethanol and dimethyl sulfoxide) have been investigated by using the third-harmonic generation (355 nm) of a mode-locked Nd:YAG laser as a pump beam and a continuous-wave (cw) He-Ne laser (632.8 nm) as a probe beam. The nonlinear refractive indices of 3-HF in the three different solvents are determined by using the Z-scan technique under an ultraviolet (UV) pump beam at a wavelength of 355 nm. It has been found that the optical switching and beam deflection effects result from the change in refractive index of 3-HF under the irradiation of the pump beam. On the basis of the analyses of absorption spectra and fluorescence spectra, we conclude that the change in refractive index of 3-HF is due to not the thermal effect but the ESIPT effect of 3-HF under the pump beam. As the ESIPT is exceedingly fast, 3-HF might be an excellent candidate for high-speed optical switching.展开更多
Direct measurement of dipole potential in biological membranes has been impossible and 3-hydroxyflavones(3HFs) have allowed detection of changes in dipole potential in biological systems.In the present study,sixteen d...Direct measurement of dipole potential in biological membranes has been impossible and 3-hydroxyflavones(3HFs) have allowed detection of changes in dipole potential in biological systems.In the present study,sixteen derivatives of 3HF with aliphatic hydrocarbon chains of different lengths at 4′-position and 6-position were synthesized.The basic fluorescence properties of 3HFs are maintained in all the probes in terms of strong blue shift in maximum fluorescence emission wavelength and>100 fold increase in quantum yield in organic solvents and in dioleoylphosphatidylcholine(DOPC) small unilamellar vesicles(SUV) in comparison to in aqueous Hepes buffer(15 mmol/L,pH 7.4).More importantly,the ability of the new compounds to report dipole potential changes in biological systems are also maintained,since all the new probes showed spectrum properties that are similar to yet different from that of F4N1,which potentially may allow more sensitive measurement of the dipole potential change in membranes.展开更多
[目的]3-(3′,4′-次甲二氧苯基)-N-正丙基丙烯酰胺是具有广谱抑菌活性的化合物,将其研制成优良环保剂型悬浮剂,可为实现田间应用提供技术依据。[方法]采用湿法研磨制备了12种不同配方的悬浮剂,通过质量指标检测确定最佳配方,测定其表...[目的]3-(3′,4′-次甲二氧苯基)-N-正丙基丙烯酰胺是具有广谱抑菌活性的化合物,将其研制成优良环保剂型悬浮剂,可为实现田间应用提供技术依据。[方法]采用湿法研磨制备了12种不同配方的悬浮剂,通过质量指标检测确定最佳配方,测定其表面张力及其在黄瓜叶面的动态接触角,并开展了防治黄瓜白粉病田间药效试验。[结果]最佳配方为3-(3′,4′-次甲二氧苯基)-N-正丙基丙烯酰胺40%(折百)、S043%、D4252%、W071%、乙二醇3%、硅酸镁铝0.4%、黄原胶0.12%、B150.12%、消泡剂X600.3%、水补足。此悬浮剂在有效成分0.27 g a.i./L时的表面张力以及在黄瓜叶面的动态接触角均小于对照药剂40%苯醚甲环唑SC,表明其具有良好的润湿性能。在有效成分0.27 g a.i./L下的防效为88.38%,与对照药剂25%嘧菌酯SC 0.20 g a.i./L相当,且对黄瓜安全。[结论]制备悬浮剂为类白色均匀悬浮液,流动性好,粒径合格,悬浮率稳定在98.5%左右,pH为4.09,黏度为452 mPa·s,入水分散性合格,热储、低温及冻融稳定性良好,未出现沉淀,各项指标均达标,对黄瓜白粉病防效优良,具有良好的开发应用前景。展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 60178025)
文摘3-hydroxyflavone (3-HF) is an organic molecule with an excited-stated intramolecular proton transfer (ESIPT) effect. All-optical switchings and beam deflections of 3-HF in three kinds of solvents (cyclohexane, ethanol and dimethyl sulfoxide) have been investigated by using the third-harmonic generation (355 nm) of a mode-locked Nd:YAG laser as a pump beam and a continuous-wave (cw) He-Ne laser (632.8 nm) as a probe beam. The nonlinear refractive indices of 3-HF in the three different solvents are determined by using the Z-scan technique under an ultraviolet (UV) pump beam at a wavelength of 355 nm. It has been found that the optical switching and beam deflection effects result from the change in refractive index of 3-HF under the irradiation of the pump beam. On the basis of the analyses of absorption spectra and fluorescence spectra, we conclude that the change in refractive index of 3-HF is due to not the thermal effect but the ESIPT effect of 3-HF under the pump beam. As the ESIPT is exceedingly fast, 3-HF might be an excellent candidate for high-speed optical switching.
文摘Direct measurement of dipole potential in biological membranes has been impossible and 3-hydroxyflavones(3HFs) have allowed detection of changes in dipole potential in biological systems.In the present study,sixteen derivatives of 3HF with aliphatic hydrocarbon chains of different lengths at 4′-position and 6-position were synthesized.The basic fluorescence properties of 3HFs are maintained in all the probes in terms of strong blue shift in maximum fluorescence emission wavelength and>100 fold increase in quantum yield in organic solvents and in dioleoylphosphatidylcholine(DOPC) small unilamellar vesicles(SUV) in comparison to in aqueous Hepes buffer(15 mmol/L,pH 7.4).More importantly,the ability of the new compounds to report dipole potential changes in biological systems are also maintained,since all the new probes showed spectrum properties that are similar to yet different from that of F4N1,which potentially may allow more sensitive measurement of the dipole potential change in membranes.
文摘[目的]3-(3′,4′-次甲二氧苯基)-N-正丙基丙烯酰胺是具有广谱抑菌活性的化合物,将其研制成优良环保剂型悬浮剂,可为实现田间应用提供技术依据。[方法]采用湿法研磨制备了12种不同配方的悬浮剂,通过质量指标检测确定最佳配方,测定其表面张力及其在黄瓜叶面的动态接触角,并开展了防治黄瓜白粉病田间药效试验。[结果]最佳配方为3-(3′,4′-次甲二氧苯基)-N-正丙基丙烯酰胺40%(折百)、S043%、D4252%、W071%、乙二醇3%、硅酸镁铝0.4%、黄原胶0.12%、B150.12%、消泡剂X600.3%、水补足。此悬浮剂在有效成分0.27 g a.i./L时的表面张力以及在黄瓜叶面的动态接触角均小于对照药剂40%苯醚甲环唑SC,表明其具有良好的润湿性能。在有效成分0.27 g a.i./L下的防效为88.38%,与对照药剂25%嘧菌酯SC 0.20 g a.i./L相当,且对黄瓜安全。[结论]制备悬浮剂为类白色均匀悬浮液,流动性好,粒径合格,悬浮率稳定在98.5%左右,pH为4.09,黏度为452 mPa·s,入水分散性合格,热储、低温及冻融稳定性良好,未出现沉淀,各项指标均达标,对黄瓜白粉病防效优良,具有良好的开发应用前景。
基金国家自然科学基金联合基金项目(U21A20485)浙江省高等教育“十四五”本科教育教学改革项目(jg20220019)+3 种基金浙江省产学合作协同育人项目(202018)浙江大学2023年度本科教学创新实践项目重点项目(202309)浙江省基础公益研究计划项目(LGG22F030008)浙江大学第一批AI For Education系列实证教学研究项目(202402)。