To explore the optimum temperature,light intensityand water conditions for seed germination of Siphonostegia chinensis Benth.,seed germination experiment were carried out under different temperatures(5/15,10/20,15/25,...To explore the optimum temperature,light intensityand water conditions for seed germination of Siphonostegia chinensis Benth.,seed germination experiment were carried out under different temperatures(5/15,10/20,15/25,20/30℃),different light intensity(14h light/10h darkness,complete darkness)and different concentrations(0%,5%,10%,15%,20%)of PEG-6000 solution.In terms of concentration,5%PEG was regarded as the low level,10%and 15%as the medium level,and 20%as the high level.The results showed that(1)Germination rate,germination potential,and germination index were increased with the rise of temperature.In addition,seed germination was significantly higher under the dark conditions than that with the 14h light/10h darkness.(2)No seed germination occurred when the temperature was below 10/20 C at 14h light/10h darkness.(3)Under 14h light/10h darkness,the germination rate,germination potential and germination index first increased and then decreased with the increase of PEG concentration.The low concentration was more beneficial to the seed germination.(4)Under the condition of complete darkness,the germination rate,germination potential and germination index decline with fluctuation with the increase of PEG concentration.Seed germination of Siphonostegia chinensis Benth.was inhibited in high concentration of PEG.展开更多
The requirements for dichroic laser mirrors continue to increase with the development of laser technology. The challenge of a dichroic laser mirror coating is to simultaneously obtain spectral performance with signifi...The requirements for dichroic laser mirrors continue to increase with the development of laser technology. The challenge of a dichroic laser mirror coating is to simultaneously obtain spectral performance with significantly different reflection or transmission properties as well as a high laser-induced damage threshold(LIDT) at two different wavelengths. Traditional dichroic laser mirrors composed of alternating high-and low-refractive-index pure materials often has difficulty achieving excellent spectral performance and high LIDTs at two wavelengths simultaneously. We propose to use a new design with mixture layers and sandwich-like-structure interfaces to meet the challenging requirements. An Al_(2) O_(3)-HfO_(2) mixture-based dichroic laser mirror, which can be used as a harmonic separator in a fusion-class laser or a pump/signal beam separator in a petawatt-class Ti-sapphire laser system, is experimentally demonstrated using e-beam deposition. The mixture-based dichroic mirror coating shows good spectral performance, fine mechanical property, low absorption, and high LIDT. For the s-polarized 7.7 ns pulses at a wavelength of 532 nm and the p-polarized 12 ns pulses at a wavelength of 1064 nm, the LIDTs are almost doubled. The excellent performance of this new design strategy with mixture layers and sandwich-like-structure interfaces suggests its wide applicability in high-performance laser coating.展开更多
基金supported by the National Natural Science Foundation of China(NSFC:41801027)the National Natural Science Foundation of China(NSFC:3170043).
文摘To explore the optimum temperature,light intensityand water conditions for seed germination of Siphonostegia chinensis Benth.,seed germination experiment were carried out under different temperatures(5/15,10/20,15/25,20/30℃),different light intensity(14h light/10h darkness,complete darkness)and different concentrations(0%,5%,10%,15%,20%)of PEG-6000 solution.In terms of concentration,5%PEG was regarded as the low level,10%and 15%as the medium level,and 20%as the high level.The results showed that(1)Germination rate,germination potential,and germination index were increased with the rise of temperature.In addition,seed germination was significantly higher under the dark conditions than that with the 14h light/10h darkness.(2)No seed germination occurred when the temperature was below 10/20 C at 14h light/10h darkness.(3)Under 14h light/10h darkness,the germination rate,germination potential and germination index first increased and then decreased with the increase of PEG concentration.The low concentration was more beneficial to the seed germination.(4)Under the condition of complete darkness,the germination rate,germination potential and germination index decline with fluctuation with the increase of PEG concentration.Seed germination of Siphonostegia chinensis Benth.was inhibited in high concentration of PEG.
基金supported by the National Natural Science Foundation of China(52104254,22378104)the Natural Science Foundation of Hubei Province(2022CFB504)the Open Subject of Engineering Research Center for Clean Production of Textile Printing and Dyeing,Ministry of Education(2023GCZX008)。
基金National Natural Science Foundation of China(61975215,U1831211)Youth Innovation Promotion Association of the Chinese Academy of Sciences,Strategic Priority Research Program of the Chinese Academy of Sciences(XDA25020000,XDB16030400)。
文摘The requirements for dichroic laser mirrors continue to increase with the development of laser technology. The challenge of a dichroic laser mirror coating is to simultaneously obtain spectral performance with significantly different reflection or transmission properties as well as a high laser-induced damage threshold(LIDT) at two different wavelengths. Traditional dichroic laser mirrors composed of alternating high-and low-refractive-index pure materials often has difficulty achieving excellent spectral performance and high LIDTs at two wavelengths simultaneously. We propose to use a new design with mixture layers and sandwich-like-structure interfaces to meet the challenging requirements. An Al_(2) O_(3)-HfO_(2) mixture-based dichroic laser mirror, which can be used as a harmonic separator in a fusion-class laser or a pump/signal beam separator in a petawatt-class Ti-sapphire laser system, is experimentally demonstrated using e-beam deposition. The mixture-based dichroic mirror coating shows good spectral performance, fine mechanical property, low absorption, and high LIDT. For the s-polarized 7.7 ns pulses at a wavelength of 532 nm and the p-polarized 12 ns pulses at a wavelength of 1064 nm, the LIDTs are almost doubled. The excellent performance of this new design strategy with mixture layers and sandwich-like-structure interfaces suggests its wide applicability in high-performance laser coating.
