Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.I...Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.In this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically characterized.Under different colored lights,S.platensis all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light intensities.At the same light intensity,different colored lights show different growth rate of S.platensis following the sequence of red>white>green>yellow>blue.The maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red LED.The energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>yellow.Transcriptomic analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism pathways.This study provides a conducive and efficient way to promote biomass production and protein accumulation of S.platensis by regulating light conditions.展开更多
Stress state of microalgal cells is caused under unfavorable conditions such as disordered light regime and depleted nitrogen. The stress state can impair photosynthetic efficiency, inhibit cell growth and result in t...Stress state of microalgal cells is caused under unfavorable conditions such as disordered light regime and depleted nitrogen. The stress state can impair photosynthetic efficiency, inhibit cell growth and result in the accumulation of triacylglycerol(TAG) from protective mechanisms. Continuous light or nitrogen starvation was applied on microalgae and performed effectively on inducing TAG production. To evaluate the light regime effect on inducing TAG production, the effect of different light regimes on nitrogen-starved Isochrysis zhangjiangensis was investigated in this work. The continuous light and nitrogen starvation elevated TAG content of biomass by 73% and 193%, respectively. Furthermore, the TAG accumulation of I. zhangjiangensis cell under nitrogen starvation decreased under aggravated stress from continuous illumination. Our results demonstrated that culturing the cells with 14 L: 10 D light regime under nitrogen starvation is the optimal mode to achieve maximal accumulation of TAG. A recovery in light regime was necessary for I. zhangjiangensis cultivation.展开更多
We theoretically and experimentally investigate a switchable spin Hall effect（SHE） of light in reflection near the Brewster angle at an air-uniaxial crystal interface.We find a large transverse spin splitting near t...We theoretically and experimentally investigate a switchable spin Hall effect（SHE） of light in reflection near the Brewster angle at an air-uniaxial crystal interface.We find a large transverse spin splitting near the Brewster angle,whose sign can be altered by rotating the optical axis.As an analogy of the SHE in an electronic system,a switchable spin accumulation in the SHE of light is detected.We are able to switch the direction of the spin accumulation by adjusting the optical axis angle of the uniaxial crystal.These findings may give opportunities for photon spin manipulating and developing a new generation of nano-photonic devices.展开更多
P-InGaN/p-GaN superlattices （SLs） are developed for a hole accumulation layer （HAL） of a blue light emitting diode （LED）. Free hole concentration as high as 2.6× 1018 cm-3 is achieved by adjusting the Cp2Mg...P-InGaN/p-GaN superlattices （SLs） are developed for a hole accumulation layer （HAL） of a blue light emitting diode （LED）. Free hole concentration as high as 2.6× 1018 cm-3 is achieved by adjusting the Cp2Mg flow rate during the growth of p-InGaN/p-GaN SLs. The p-InGaN/p-GaN SLs with appropriate Cp2Mg flow rates are then incorporated between the multi-quantum well and A1GaN electron blocking layer as an HAL, which leads to the enhancement of light output power by 29% at 200 mA, compared with the traditional LED without such SL HAL. Meanwhile, the efficiency droop is also effectively alleviated in the LED with the SL HAL. The improved performance is attributed to the increased hole injection efficiency, and the reduced electron leakage by inserting the p-type SL HAL.展开更多
In this paper, we conduct theoretical research on design and implementation on wind and light complementary LED lighting controller based on the novel base board packaging technology. LED, as a kind of device can conv...In this paper, we conduct theoretical research on design and implementation on wind and light complementary LED lighting controller based on the novel base board packaging technology. LED, as a kind of device can convert electric power into visible light directly the homomorphism of semiconductor devices, with high efficiency and small energy consumption, good light quality, use safety, long service life, green environmental protection, flexible control as this is common lamps and lanterns is incomparable advantage. Therefore, it is considered to be 21 century of a new generation of lighting source. Based on the superiority of LED, it is widely applied in many fields of lighting. To enhance the traditional solar based pure LED system, we enhance it with the combination of the wind power and the optimized controller that holds specific meaning.展开更多
Taking the ecological, environmental protection as the starting point, in view of our country road lighting with excessive power consumption problems, the paper proposes design scheme of S type spiral lamp that is sui...Taking the ecological, environmental protection as the starting point, in view of our country road lighting with excessive power consumption problems, the paper proposes design scheme of S type spiral lamp that is suitable the coastal city, highway zone by solar energy combined with wind energy generation. This design uses class of S spiral with the highest wind energy utilization rate, and the surface has materials that can absorb solar energy, its structure built in simple and the design fit standard proportion lamp. This design has the advantages of beautiful apnearance, easv to produce, has the very big use value.展开更多
基金the National Natural Science Foundation of China(Nos.42061134020,32070380)the Natural Science Foundation of Shandong Province(No.ZR2019ZD17)。
文摘Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.In this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically characterized.Under different colored lights,S.platensis all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light intensities.At the same light intensity,different colored lights show different growth rate of S.platensis following the sequence of red>white>green>yellow>blue.The maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red LED.The energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>yellow.Transcriptomic analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism pathways.This study provides a conducive and efficient way to promote biomass production and protein accumulation of S.platensis by regulating light conditions.
基金supported by the National High Technology Research and Development Program ‘863’ (No. 2012 AA052101)the Hundred Talent Program of the Chinese Academy of Sciences (No. A1097)
文摘Stress state of microalgal cells is caused under unfavorable conditions such as disordered light regime and depleted nitrogen. The stress state can impair photosynthetic efficiency, inhibit cell growth and result in the accumulation of triacylglycerol(TAG) from protective mechanisms. Continuous light or nitrogen starvation was applied on microalgae and performed effectively on inducing TAG production. To evaluate the light regime effect on inducing TAG production, the effect of different light regimes on nitrogen-starved Isochrysis zhangjiangensis was investigated in this work. The continuous light and nitrogen starvation elevated TAG content of biomass by 73% and 193%, respectively. Furthermore, the TAG accumulation of I. zhangjiangensis cell under nitrogen starvation decreased under aggravated stress from continuous illumination. Our results demonstrated that culturing the cells with 14 L: 10 D light regime under nitrogen starvation is the optimal mode to achieve maximal accumulation of TAG. A recovery in light regime was necessary for I. zhangjiangensis cultivation.
基金Project supported by the National Natural Science Foundation of China (Grants Nos. 61025024 and 11074068)the Hunan Provincial Natural Science Foundation of China (Grant No. 12JJ7005)
文摘We theoretically and experimentally investigate a switchable spin Hall effect（SHE） of light in reflection near the Brewster angle at an air-uniaxial crystal interface.We find a large transverse spin splitting near the Brewster angle,whose sign can be altered by rotating the optical axis.As an analogy of the SHE in an electronic system,a switchable spin accumulation in the SHE of light is detected.We are able to switch the direction of the spin accumulation by adjusting the optical axis angle of the uniaxial crystal.These findings may give opportunities for photon spin manipulating and developing a new generation of nano-photonic devices.
文摘P-InGaN/p-GaN superlattices （SLs） are developed for a hole accumulation layer （HAL） of a blue light emitting diode （LED）. Free hole concentration as high as 2.6× 1018 cm-3 is achieved by adjusting the Cp2Mg flow rate during the growth of p-InGaN/p-GaN SLs. The p-InGaN/p-GaN SLs with appropriate Cp2Mg flow rates are then incorporated between the multi-quantum well and A1GaN electron blocking layer as an HAL, which leads to the enhancement of light output power by 29% at 200 mA, compared with the traditional LED without such SL HAL. Meanwhile, the efficiency droop is also effectively alleviated in the LED with the SL HAL. The improved performance is attributed to the increased hole injection efficiency, and the reduced electron leakage by inserting the p-type SL HAL.
文摘In this paper, we conduct theoretical research on design and implementation on wind and light complementary LED lighting controller based on the novel base board packaging technology. LED, as a kind of device can convert electric power into visible light directly the homomorphism of semiconductor devices, with high efficiency and small energy consumption, good light quality, use safety, long service life, green environmental protection, flexible control as this is common lamps and lanterns is incomparable advantage. Therefore, it is considered to be 21 century of a new generation of lighting source. Based on the superiority of LED, it is widely applied in many fields of lighting. To enhance the traditional solar based pure LED system, we enhance it with the combination of the wind power and the optimized controller that holds specific meaning.
文摘Taking the ecological, environmental protection as the starting point, in view of our country road lighting with excessive power consumption problems, the paper proposes design scheme of S type spiral lamp that is suitable the coastal city, highway zone by solar energy combined with wind energy generation. This design uses class of S spiral with the highest wind energy utilization rate, and the surface has materials that can absorb solar energy, its structure built in simple and the design fit standard proportion lamp. This design has the advantages of beautiful apnearance, easv to produce, has the very big use value.
