Degradation of Japanese lacquer caused by light irradiation was examined at various wavelengths. By exposing lacquer specimens to a narrow monochromatic light band isolated from dispersed polychromatic light emitted b...Degradation of Japanese lacquer caused by light irradiation was examined at various wavelengths. By exposing lacquer specimens to a narrow monochromatic light band isolated from dispersed polychromatic light emitted by a Xe lamp source, the wavelength sensitivity characteristics of lacquer degradation could be determined on the basis of radiant energy. Tame-Urushi (brown) lacquer displayed peak degradation maxima at 220 and 315 nm. A broad shoulder peak was also observed in UVA. For Shu-Urushi (cinnabar) lacquer, in addition to peaks in the UVA–UVB range, a large degree of degradation was observed following exposure to light in the visible range. Ao-Urushi (green) lacquer showed similar characteristics, although it was less prone to degradation. Similarly, Shin-Urushi (black) lacquer showed little change in response to light, although UV light caused limited degradation. These results indicate that along with the damage caused by UVA and UVB, visible light in the range 510 - 650 nm may also have a significant degradation effect. Our results provide experimental evidence that Japanese lacquer responds differently to light of various wavelengths and that specific wavelengths, including visible light, can cause significant degradation.展开更多
In this study,the halogen exchange reactions are investigated between KI or methylamine iodide in aqueous solution and CsPbBr_(3)NCs in toluene.The mass transfer process on the interface between water and toluene affe...In this study,the halogen exchange reactions are investigated between KI or methylamine iodide in aqueous solution and CsPbBr_(3)NCs in toluene.The mass transfer process on the interface between water and toluene affects the halogen exchange time and e fficiency.Stirring and heating can effectively improve the halogen exchange e fficiency and increases the sensing sensitivity.The photoluminescence wavelength shift of CsPbBr_(3)NCs shows good linear relationship with the concentration of I-in the range from 0 to 20 nmol/L with the detection limit of 0.2 nmol/L I^(-).Taking H_(2)O_(2)as a typical water-soluble oxide,the method is applied to the colorimetric sensing of H_(2)O_(2)in water solution.After the optimization of sensing conditions,the obvious wavelength shift could be observed with the different concentration range of H_(2)O_(2).A good linear relationship between the wavelength shift and the H_(2)O_(2)concentration from 0 to 1.0 mmol/L with the detection limit of 0.05 mmol/L H_(2)O_(2)could be found.展开更多
文摘Degradation of Japanese lacquer caused by light irradiation was examined at various wavelengths. By exposing lacquer specimens to a narrow monochromatic light band isolated from dispersed polychromatic light emitted by a Xe lamp source, the wavelength sensitivity characteristics of lacquer degradation could be determined on the basis of radiant energy. Tame-Urushi (brown) lacquer displayed peak degradation maxima at 220 and 315 nm. A broad shoulder peak was also observed in UVA. For Shu-Urushi (cinnabar) lacquer, in addition to peaks in the UVA–UVB range, a large degree of degradation was observed following exposure to light in the visible range. Ao-Urushi (green) lacquer showed similar characteristics, although it was less prone to degradation. Similarly, Shin-Urushi (black) lacquer showed little change in response to light, although UV light caused limited degradation. These results indicate that along with the damage caused by UVA and UVB, visible light in the range 510 - 650 nm may also have a significant degradation effect. Our results provide experimental evidence that Japanese lacquer responds differently to light of various wavelengths and that specific wavelengths, including visible light, can cause significant degradation.
基金funded by National Natural Science Foundations of China(21876141)the Shenzhen Science and Technology Project(JCYJ20180306172823786)
文摘In this study,the halogen exchange reactions are investigated between KI or methylamine iodide in aqueous solution and CsPbBr_(3)NCs in toluene.The mass transfer process on the interface between water and toluene affects the halogen exchange time and e fficiency.Stirring and heating can effectively improve the halogen exchange e fficiency and increases the sensing sensitivity.The photoluminescence wavelength shift of CsPbBr_(3)NCs shows good linear relationship with the concentration of I-in the range from 0 to 20 nmol/L with the detection limit of 0.2 nmol/L I^(-).Taking H_(2)O_(2)as a typical water-soluble oxide,the method is applied to the colorimetric sensing of H_(2)O_(2)in water solution.After the optimization of sensing conditions,the obvious wavelength shift could be observed with the different concentration range of H_(2)O_(2).A good linear relationship between the wavelength shift and the H_(2)O_(2)concentration from 0 to 1.0 mmol/L with the detection limit of 0.05 mmol/L H_(2)O_(2)could be found.
