Sprouts are ready-to-eat and are recognized worldwide as functional components of the human diet.Recent advances in innovative agricultural techniques could enable an increase in the production of healthy food.The use...Sprouts are ready-to-eat and are recognized worldwide as functional components of the human diet.Recent advances in innovative agricultural techniques could enable an increase in the production of healthy food.The use of light-emitting diode(LED)in indoor agricultural production could alter the biological feedback loop,increasing the functional benefits of plant foods such as wheat and lentil sprouts and promoting the bioavailability of nutrients.The effects of white(W),red(R),and blue(B)light were investigated on the growth parameters and nutritional value of wheat and lentil sprouts.In the laboratory,seeds were sown under three different LED treat-ments:white,red,and blue light,while normal incandescent light served as a control.Percentage seed germina-tion improved by 18.34%and 12.67%for wheat and 18.34%and 12.67%for lentil sprouts under LED treatments R and B,respectively.An increase in total soluble protein and sugar by 33.4%and 9.23%in wheat and by 31.5%and 5.87%in lentils was observed under the R LED treatment.Vitamin C concentrations in wheat and lentils were significantly increased by R LED compared to all other treatments.Other parameters,including potassium and sodium concentrations,were significantly increased under red and blue light compared to the control;white light,on the other hand,significantly decreased all these parameters.According to the experimental data,red and blue LED light could be beneficial in the production of functional wheat and lentil sprouts with high nutrient concentrations.展开更多
Miniaturized light sources at telecommunication wavelengths are essential components for on-chip optical communication systems.Here,we report the growth and fabrication of highly uniform p-i-n core-shell InGaAs/InP si...Miniaturized light sources at telecommunication wavelengths are essential components for on-chip optical communication systems.Here,we report the growth and fabrication of highly uniform p-i-n core-shell InGaAs/InP single quantum well(QW)nanowire array light emitting diodes(LEDs)with multi-wavelength and high-speed operations.Two-dimensional cathodoluminescence mapping reveals that axial and radial QWs in the nanowire structure contribute to strong emission at the wavelength of~1.35 and~1.55μm,respectively,ideal for low-loss optical communications.As a result of simultaneous contributions from both axial and radial QWs,broadband electroluminescence emission with a linewidth of 286 nm is achieved with a peak power of~17μW.A large spectral blueshift is observed with the increase of applied bias,which is ascribed to the band-filling effect based on device simulation,and enables voltage tunable multi-wavelength operation at the telecommunication wavelength range.Multi-wavelength operation is also achieved by fabricating nanowire array LEDs with different pitch sizes on the same substrate,leading to QW formation with different emission wavelengths.Furthermore,high-speed GHz-level modulation and small pixel size LED are demonstrated,showing the promise for ultrafast operation and ultracompact integration.The voltage and pitch size controlled multi-wavelength highspeed nanowire array LED presents a compact and efficient scheme for developing high-performance nanoscale light sources for future optical communication applications.展开更多
The phosphors of KY_(1-x)(MoO_(4))_(2-y)(WO_(4))y:xLn^(3+)(Ln^(3+)=Tm^(3+),Dy^(3+),Eu^(3+))were synthesized by using a sol-gel method.Then,the crystal structure,luminescence properties,energy transfer,and white emissi...The phosphors of KY_(1-x)(MoO_(4))_(2-y)(WO_(4))y:xLn^(3+)(Ln^(3+)=Tm^(3+),Dy^(3+),Eu^(3+))were synthesized by using a sol-gel method.Then,the crystal structure,luminescence properties,energy transfer,and white emission of the prepared materials were researched.The molar ratio of the anion group on the photoluminescence(PL)emission and excitation intensity were investigated,revealing that the optimum intensity could be obtained by using=3:1.The optimal Dy^(3+) doping concentration of KY(MoO_(4))1.5(WO4)0.5was obtained.In addition,the color-tunable emissions of Dy^(3+)/Eu^(3+)-codoped KY(MoO_(4))1.5(WO4)0.5phosphors were observed because of the effective energy transfer(ET)from Dy^(3+)to Eu^(3+)ions.Finally,by doping appropriate concentrations of Tm^(3+),Dy^(3+),and Eu^(3+)and different concentrations of(WO_(4))^(2-),white light emitting phosphors KY_(0.92)(WO_(4))2:0.01Tm^(3+),0.06Dy^(3+),0.01Eu^(3+)with excellent color-rending properties were obtained.The chromaticity coordinate was calculated as(x=0.3238,y=0.3173),closing to the artificial daylight(D65,x=0.313,y=0.329)illuminant,and which indicates the potential application of near ultraviolet White light-emitting diodes(WLEDs).展开更多
基金Supported by Researchers Supporting Project Number(RSP2024R410)King Saud University,Riyadh,Saudi Arabia.
文摘Sprouts are ready-to-eat and are recognized worldwide as functional components of the human diet.Recent advances in innovative agricultural techniques could enable an increase in the production of healthy food.The use of light-emitting diode(LED)in indoor agricultural production could alter the biological feedback loop,increasing the functional benefits of plant foods such as wheat and lentil sprouts and promoting the bioavailability of nutrients.The effects of white(W),red(R),and blue(B)light were investigated on the growth parameters and nutritional value of wheat and lentil sprouts.In the laboratory,seeds were sown under three different LED treat-ments:white,red,and blue light,while normal incandescent light served as a control.Percentage seed germina-tion improved by 18.34%and 12.67%for wheat and 18.34%and 12.67%for lentil sprouts under LED treatments R and B,respectively.An increase in total soluble protein and sugar by 33.4%and 9.23%in wheat and by 31.5%and 5.87%in lentils was observed under the R LED treatment.Vitamin C concentrations in wheat and lentils were significantly increased by R LED compared to all other treatments.Other parameters,including potassium and sodium concentrations,were significantly increased under red and blue light compared to the control;white light,on the other hand,significantly decreased all these parameters.According to the experimental data,red and blue LED light could be beneficial in the production of functional wheat and lentil sprouts with high nutrient concentrations.
文摘Miniaturized light sources at telecommunication wavelengths are essential components for on-chip optical communication systems.Here,we report the growth and fabrication of highly uniform p-i-n core-shell InGaAs/InP single quantum well(QW)nanowire array light emitting diodes(LEDs)with multi-wavelength and high-speed operations.Two-dimensional cathodoluminescence mapping reveals that axial and radial QWs in the nanowire structure contribute to strong emission at the wavelength of~1.35 and~1.55μm,respectively,ideal for low-loss optical communications.As a result of simultaneous contributions from both axial and radial QWs,broadband electroluminescence emission with a linewidth of 286 nm is achieved with a peak power of~17μW.A large spectral blueshift is observed with the increase of applied bias,which is ascribed to the band-filling effect based on device simulation,and enables voltage tunable multi-wavelength operation at the telecommunication wavelength range.Multi-wavelength operation is also achieved by fabricating nanowire array LEDs with different pitch sizes on the same substrate,leading to QW formation with different emission wavelengths.Furthermore,high-speed GHz-level modulation and small pixel size LED are demonstrated,showing the promise for ultrafast operation and ultracompact integration.The voltage and pitch size controlled multi-wavelength highspeed nanowire array LED presents a compact and efficient scheme for developing high-performance nanoscale light sources for future optical communication applications.
文摘The phosphors of KY_(1-x)(MoO_(4))_(2-y)(WO_(4))y:xLn^(3+)(Ln^(3+)=Tm^(3+),Dy^(3+),Eu^(3+))were synthesized by using a sol-gel method.Then,the crystal structure,luminescence properties,energy transfer,and white emission of the prepared materials were researched.The molar ratio of the anion group on the photoluminescence(PL)emission and excitation intensity were investigated,revealing that the optimum intensity could be obtained by using=3:1.The optimal Dy^(3+) doping concentration of KY(MoO_(4))1.5(WO4)0.5was obtained.In addition,the color-tunable emissions of Dy^(3+)/Eu^(3+)-codoped KY(MoO_(4))1.5(WO4)0.5phosphors were observed because of the effective energy transfer(ET)from Dy^(3+)to Eu^(3+)ions.Finally,by doping appropriate concentrations of Tm^(3+),Dy^(3+),and Eu^(3+)and different concentrations of(WO_(4))^(2-),white light emitting phosphors KY_(0.92)(WO_(4))2:0.01Tm^(3+),0.06Dy^(3+),0.01Eu^(3+)with excellent color-rending properties were obtained.The chromaticity coordinate was calculated as(x=0.3238,y=0.3173),closing to the artificial daylight(D65,x=0.313,y=0.329)illuminant,and which indicates the potential application of near ultraviolet White light-emitting diodes(WLEDs).
