- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Electroluminescence from amorphous GIZO/p-GaN heterojunction light-emitting diodes
摘要： The electroluminescence from the amorphous gallium-indium-zinc oxide (a-GIZO)/p-GaN heterojunction light-emitting diodes (LEDs) were demonstrated. The heterojunction LEDs showed a current flow under both forward and reverse bias voltages. The light emissions were observed at around 410 nm (originating from p-GaN) and ~450–800 nm (originating from interfacial layer and/or from a-GIZO), which were particularly pronounced under reverse bias condition. As a result, the standard white light with the chromaticity coordinate of (0.2899, 0.3034) was obtained.
关键词： Light emitting diode,Gallium-indium-zinc oxide,Heterojunction,Amorphous
更新于2025-09-23 15:21:01
-
High color rendering index white light-emitting diode based on enviromental friendly carbon and AIZS nanoparticles
摘要： Solid-state white light-emitting diodes (WLEDs) based on carbon dots (CDs) have attracted broad attention due to their high brightness and enviromental friendly. However, the poor performance including low efficiency and weak emission of red-emitting CDs further hindered its application on WLED devices. Herein, we constructed one outstanding WLEDs device by combining carbon dots (blue emission, green emission) and Ag-In-Zn-S (AIZS) nanoparticles with red emission. Moreover, by adjusting the volume ratio of the three materials, the WLED showed maximum color rendering index (CRI) of 97 and maintained CRI value above 90 during the correlated color temperature (CCT) tuned from 3387 to 8018 K. Meanwhile, the as-fabricated WLED devices showed excellent color rendering stability during the working voltages from 3.0V to 3.5V. This work may provide one new avenue for development of low-cost, environmental friendly and high-performance CDs phosphor-based WLEDs.
关键词： AIZS nanoparticles,color rendering index,white light-emitting diode,carbon dots,environmental friendly
更新于2025-09-23 15:21:01
-
[IEEE 2018 4th International Conference on Applied and Theoretical Computing and Communication Technology (iCATccT) - Mangalore, India (2018.9.6-2018.9.8)] 2018 4th International Conference on Applied and Theoretical Computing and Communication Technology (iCATccT) - A concept of energy efficient LED lighting using Power-over-Ethernet (PoE) technology
摘要： LED lighting is found universal acceptance for being affordable and energy ef?cient. The next big step for LED lighting is enabling LED ?xtures to work in Internet-of- Things (IoT) infrastructure. Power-over-Ethernet(PoE) standard delivers power and data via a Ethernet cable from a power source such as a hub directly to the network port of a connected powered device, in the case of lighting the powered device can be a LED bulb.In this paper the concept of energy ef?cient LED lighting using PoE technology is discussed in brief.The bene?ts PoE technology provides and challenges that needs to be addressed are highlighted.
关键词： energy,lighting,ef?ciency,light emitting diode,solid state lighting,Power over Ethernet,POE,LED,SSL
更新于2025-09-23 15:21:01
-
Blue LED phototherapy in preterm infants: effects on an oxidative marker of DNA damage
摘要： background Phototherapy is used on the majority of preterm infants with unconjugated hyperbilirubinaemia. The use of fluorescent tube phototherapy is known to induce oxidative DNA damage in infants and has largely been replaced by blue light- emitting diode phototherapy (BLP). To date, it is unknown whether BLP also induces oxidative DNA damage in preterm infants. Objective To determine whether BLP in preterm infants induces oxidative DNA damage as indicated by 8- hydroxy-2′deoxyguanosine (8- OHdG). Design Observational cohort study. Methods Urine samples (n=481) were collected in a cohort of 40 preterm infants (24–32 weeks’ gestational age) during the first week after birth. Urine was analysed for the oxidative marker of DNA damage 8- OHdG and for creatinine, and the 8- OHdG/creatinine ratio was calculated. Durations of phototherapy and levels of irradiance were monitored as well as total serum bilirubin concentrations. results BLP did not alter urinary 8- OHdG/creatinine ratios (B=0.2, 95% CI ?6.2 to 6.6) at either low (10–30 μW/cm2/nm) or high (>30 μW/cm2/nm) irradiance: (B=2.3, 95% CI ?5.7 to 10.2 and B=?3.0, 95% CI ?11.7 to 5.6, respectively). Also, the 8- OHdG/creatinine ratios were independent on phototherapy duration (B=?0.1, 95% CI ?0.3 to 0.1). Conclusions BLP at irradiances up to 35 μW/cm2/nm given to preterm infants ≤32 weeks’ gestation does not affect 8- OHdG, an oxidative marker of DNA damage.
关键词： preterm infants,phototherapy,8-hydroxy-2′deoxyguanosine,blue light-emitting diode phototherapy,oxidative DNA damage
更新于2025-09-23 15:21:01
-
Effect of supplementing blue/green LED to white LED light on broiler growth, stress and welfare
摘要： LED lighting provides an affordable lighting option for use in commercial poultry production. However, more information is needed to understand the effects of LED color on broiler welfare and growth. Five consecutive flocks (1 in summer, 1 in fall, 2 in winter, and 1 in spring) of straight run Ross 708 x Ross 708 broilers were reared in commercial type barns to 45 d. In treatment WO (white only), birds were reared under white LED only (Agrishift? MLB, Once Inc., Plymouth, MN). In treatment WS (white supplemented), birds were reared under white LED (Agrishift? MLB, Once Inc., Plymouth, MN) in the center aisle, with supplemental blue/green LED (Agrishift? MLBg, Once Inc., Plymouth, MN) above feed and water lines on either side of the barn. Each barn housed 26,200 chicks, and there were 2 barns in each treatment (n=52,400 per treatment). Treatments were rotated among barns between each flock. On d 45 blood samples were collected from 20 birds per barn (n=40/treatment) to assess plasma corticosterone (CORT) and heterophil/lymphocyte (H/L) ratio. On d 45, 100 birds/barn (n=200/treatment) were weighed individually and assigned scores for hock burn and foot pad dermatitis. All measures were affected by trial (P < 0.001). Plasma CORT and body weight were affected by the treatment*trial interaction (P ≤ 0.001). Overall, birds in the WS treatment had higher d 45 live body weight (P < 0.001) and lower hock burn scores (P = 0.032) than birds in the WO treatment. Birds in the WS treatment had higher d 45 body weight overall (P < 0.001) and in trials 1, 3 and 5, although overall body weight was lower in trials 1, 3 and 5 than in trials 2 and 4. Supplemental blue/green LED improved hock burn scores and increased d 45 body weight overall. However, trial differences suggest that more data is needed to determine whether supplementing blue/green LED to white LED improves body weight gain in mixed sex broiler chickens.
关键词： growth,stress,welfare,light emitting diode,broiler
更新于2025-09-23 15:21:01
-
An Empirical Study on the Absorption of Carbon Dioxide in OLED-Mixed Concrete through Carbonation Reaction
摘要： In this study, the ability to absorb CO2 in concrete, in terms of carbonation reaction, was evaluated by utilizing organic light emitting diode (OLED) waste glass as a cementitious binder. The substitution level was set 10%, 20%, and 30% by weight of the binder, and water to binder ratio was kept at 0.4 for all mixes. Prior to estimate the concentration of CO2 uptake, an influence of OLED replacement on pozzolanic reactivity and thus strength development of concrete was investigated. CO2 absorption was calculated by molar concentration of carbonatable phases and carbonation depth derived from quantitative X-ray analysis and accelerating carbonation test, respectively. As a result, the blended concrete exhibits a higher strength with an increase of OLED replacement ratio due to the pozzolanic reaction, compared to the control specimen. Also, the content of CO2 uptake for the mixtures was increased with the substitution level of OLED, of which the OLED-mixed concrete was 1.81- 2.76 times higher than the ordinary Portland cement (OPC) 100% concrete. This behavior may be attributed to an increased rate of carbonation progress. Therefore, it is concluded that the capacity of CO2 absorption is improved by the use of OLED glass powder as a cementitious material in a concrete mixture.
关键词： Carbonation,Display byproduct,Pozzolanic reaction,Organic light emitting diode,CO2 absorption
更新于2025-09-23 15:21:01
-
Mixed 2D/3D perovskite with fine phase control modulated by a novel cyclopentanamine hydrobromide for better stability in light-emitting diodes
摘要： The mixed 2D/3D perovskite has been proved to be a promising candidate to increase the exciton binding energy in perovskite light-emitting diodes (PeLEDs). However, the complex phase distribution and impurity (usually referring to ligands) limit the stability of the corresponding PeLEDs. Here, a novel molecule, cyclopentanamine hydrobromide (CyPA·HBr), is adopted to construct a mixed 2D/3D perovskite by partial substitution of FA with CyPA, realizing fine phase control for improved device stability. The adoption of CyPA·HBr helps to tune perovskite grain growth and passivate the defect, resulting in high coverage and smooth thin film with improved photoluminescence property. The PeLEDs with an optimized CyPA·HBr concentration of a molar ratio of 40% exhibit a pure green emission with a full width at half maximum of 22 nm, an external quantum efficiency of 6.55%, and a maximum brightness of 9408 cd m?2 simultaneously. Interestingly, the CyPA·HBr-based device shows a half-lifetime two times longer than the one based on the most commonly used ligand of phenethylammonium bromide (PEA·HBr), assigned to the better phase control ability of CyPA·HBr in 2D/3D perovskite. Those results testify the importance of ligands to modulate perovskite phase along with efficient passivation defects for better stability of PeLEDs.
关键词： Phase control,Stability,Perovskite,Light-emitting diode,Defect passivation
更新于2025-09-23 15:21:01
-
Purine-based thermally activated delayed fluorescence emitters for efficient organic light-emitting diodes
摘要： Organic fluorescent materials possessing thermally activated delayed fluorescence (TADF) characteristics have attracted tremendous attention. Herein, two TADF emitters (1PXZP and 2PXZP) based on a novel biological base acceptor of 9-methylpurine and commonly used donor of phenoxazine (PXZ) have been successfully synthesized and characterized. Both target compounds possess nearly orthogonal configurations to reduce singlet-triplet splitting energy (ΔEST) for remarkable TADF character. The two emitters show good photoluminescence quantum yields (PLQYs), and thus the organic light-emitting diodes employing 1PXZP and 2PXZP as emitters display good performance with maximum external quantum efficiencies of 10.6% and 13.8%, respectively. The efficiencies of 1PXZP based device show nearly no roll-off at 100 cd m-2 luminance due to the short delayed lifetime (τd) of 3.2 μs. This work manifests that the biological base is a promising acceptor for designing TADF materials.
关键词： Thermally activated delayed fluorescence,organic light-emitting diode,aggregation-induced emission,purine
更新于2025-09-23 15:21:01
-
A High-Power-Factor Dimmable LED Driver with Integrated Boost Converter and Half-Bridge-Topology Converter
摘要： This paper proposes a dimmable light-emitting diode (LED) driver featuring a high power factor and zero-voltage switching on (ZVS). The circuit is obtained by integrating a boost converter and a dc-dc converter with half-bridge topology. The high power factor is achieved by operating the boost converter in discontinuous current mode (DCM). The LEDs are dimmed by the control scheme of asymmetrical pulse-width modulation (ASPWM). The developed circuit eliminates the inherited dc-o?set current of the transformer in a conventional asymmetrical half-bridge converter by introducing a balance capacitor. Both active switches can operate at ZVS by freewheeling the boost inductor current and the transformer magnetizing current to discharge the energy stored in their parasitic capacitance. The circuit operation is analyzed in detailed, and mathematical equations are derived. Finally, a 115-W prototype circuit for driving high brightness LEDs was built and tested. The experimental results verify the feasibility of the proposed LED driver with satisfactory performance. It can achieve a high power factor and ZVS operation.
关键词： power-factor correction,half-bridge converter,zero-voltage switching on (ZVS),asymmetrical pulse-width modulation (ASPWM),light-emitting diode (LED)
更新于2025-09-23 15:21:01
-
Calcium-tributylphosphine oxide passivation enables the efficiency of pure-blue perovskite light-emitting diode up to 3.3%
摘要： Metal halide perovskites are attractive for light-emitting diodes due to their superior optoelectronic properties such as tunable bandgaps, high photoluminescence quantum yields (PLQYs), high color purities and solution processability. In the past several years, impressive progress has been made in perovskite light-emitting diodes (PeLEDs) via microstructure engineering, charge balancing, surface defect passivation, metal ion doping and dimensional engineering. As such, the green, red and near-infrared PeLEDs have achieved impressive external quantum efficiencies (EQEs) exceeding 20%. However, the performances of pure-blue PeLEDs, i.e., brightness and EQEs, still lag largely behind those of the green and red counterparts, which severely impedes the PeLED application in full-color display and solid-state lighting.
关键词： passivation,pure-blue,perovskite,calcium-tributylphosphine oxide,light-emitting diode
更新于2025-09-23 15:21:01