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Although the tandem WOLED have the potential of high efficiency and long lifetime, the high voltage of tandem structure usually limits its application inAR/VR products. To achieve low voltage WOLED, it is necessary to develop single structure. Most of the reported single WOLED with the use of TADF materials show a relatively large CIE coordinates. In this work, we use the combination of blue fluorescence and yellow TADF materials with a 1‐2 nm p‐type interlayer material between them. The energy is transferred from blue fluorescence to TADF. And finally, the single WOLED with tunable color temperature was realized. The CIE coordinates can be tuned from the warm white point of (0.313, 0.323) to the cold white point of (0.285, 0.279). The roll‐off of efficiency from 240 nit to 3000 nit is lower than 10%, and the lifetime (LT95) can reach 1300 h at 1000 nit. [ABSTRACT FROM AUTHOR]

In this paper, a novel CGL structure is designed and studied to improve the lateral leakage in stacked OLED devices. Experiments confirmed that the position of transverse leakage mainly occurred in the CGL layer, and the new CGL structure was realized by optimizing the n‐CGL material. Compared with the reference CGL structure device, the voltage of the new structure device decreased by 0.05v, and the current efficiency increased by 5%. The average value of the color gamuts was improved by 5%, demonstrating the effectiveness and stability of the new CGL structure. The mechanism of the new CGL structure was verified by EOD. The carrier transmission performance of the new CGL structure was worse, but the carrier injection performance was improved, so as to improve the lateral leakage problem under the premise of ensuring the role of CGL. [ABSTRACT FROM AUTHOR]

Due to its high quantum yield and unique spectral characteristics, quantum dots (QDs) color conversion materials have attracted great attention in the application of luminescent display products. However, there is a lack of effective optical model for QD color conversion materials, especially for the propagation and distribution of light, when the QD ink contains scattering particles. In this paper, a full‐view optical model of QD conversion and blue backlight device architecture is established. The model can not only output the spectral information in the front view, but also predict the spectral information of the QD color conversion device in other different views. At the same time, the effects of QD concentration, thickness, particle size and refractive index on the luminous efficiency of the device structure are also studied by using this optical model. On the other hand, the influence of conversion efficiency of QD and EL backlight on the power consumption and lifetime of QD products is also studied by using this optical model. The model can realize the output of the optical influence on the future products by the parameters related to QD color conversion materials and backlight without actual device fabrication, which can greatly reduce time and labor cost. [ABSTRACT FROM AUTHOR]

A novel CGL structure is designed and studied to improve the lateral leakage in stacked OLED devices. Experiments confirmed that the position of transverse leakage mainly occurred in the CGL layer, and the new CGL structure was realized by optimizing the n‐CGL material. Compared with the reference CGL structure device, the voltage of the new structure device decreased by 0.05v, and the current efficiency increased by 5%. The average value of the color gamuts was improved by 5%, demonstrating the effectiveness and stability of the new CGL structure. The mechanism of the new CGL structure was verified by EOD. The carrier transmission performance of the new CGL structure was worse, but the carrier injection performance was improved, so as to improve the lateral leakage problem under the premise of ensuring the role of CGL. [ABSTRACT FROM AUTHOR]

According to the demand of image quality improvement, the color gamut standard has been adjusted from DCI‐P3 to BT.2020. At present, the color gamut of some QD products can reach 80%~90%, while that of white OLED products is only about 75%. In this paper, the composite film with SiO2/SiNX distributed Bragg resonator (DBR) structure is designed and studied. The results show that the film can form a strong microcavity structure with simultaneous enhancement of RGB for white OLED devices, which overcomes the bottleneck that the strong microcavity structure can't be used in white OLED devices. It can effectively improve the performance of OLED devices, and at the same time, it has the water vapor barrier effect. It can realize the integration of multiple effects such as high color gamut, low power consumption and reliability improvement in product applications. Using the refractive index difference of SiO2/SiNx thin film, the DBR structure was fabricated by carefully designing the thickness. Based on this DBR structure, a white OLED device is fabricated. The external quantum efficiency of the device is improved, and the color gamut is up to 85% (BT.2020), which is 11.2% higher than that of the device without DBR structure. Compared with the device without DBR structure, it has reached the QD display level, and the white light power consumption is reduced by 34.1%, HDR power consumption is reduced by 20.3%, and the overall performance is greatly improved. It provides technical support for products with high color gamut, low power consumption and long life. [ABSTRACT FROM AUTHOR]

We report a highly enhanced light extraction from a top emission organic light emitting diode with little image blurring. Integration of a high refractive index micro lens array on the top of the transparent indium zinc oxide top electrode of a green and blue OLED shows a significant EQE gain of 16% and 8%, respectively. [ABSTRACT FROM AUTHOR]

Bacterial endophthalmitis (BE) is an acute eye infection and potentially irreversible blinding ocular disease. The empirical intravitreous injection of antibiotic is the primary treatment once diagnosed as BE. However, the overuse of antibiotic contributes to the drug resistance of pathogens and the retinal toxicity of antibiotic limits its application in clinic. Herein, a cationic aggregation‐induced emission luminogens named with triphenylamine thiophen pyridinium (TTPy) is reported for photodynamic treatment of BE. TTPy can selectively discriminate and kill bacteria efficiently over normal ocular cells. More importantly, TTPy shows excellent antibacterial ability in BE rat models infected by Staphylococcus aureus. Meanwhile, the bacterial killing behavior triggered by TTPy induces innate immune response at an early stage of infection, limiting subsequent robust inflammation and protecting retina from bacterial toxins and inflammation‐induced bystander damage. In addition, TTPy performs better antibacterial ability than commercially used Rose Bengal, suggesting its excellent capability of vision salvage in acute BE. This study exhibits an efficient photodynamic antibacterial treatment to BE, which induces an early intraocular immune response and saves useful vision, endowing TTPy a promising potential for clinical application of ocular infections. [ABSTRACT FROM AUTHOR]

Next generation WOLED displays demand high color gamut and low power consumption, but it is a severe challenge for the WOLED display technology to meet the needs for high color gamut and low power consumption simultaneously. In this paper, with the optimization of WOLED spectrum which was well matched with CF, wide color gamut close to 99% at DCI‐P3 standard and lower power consumption of W/R/G/B as well as BDR power consumption is obtained. [ABSTRACT FROM AUTHOR]

A series of bottom‐emitting Blue OLEDs with an optimal efficiency and lifetime are successfully fabricated by introducing different electrical material combinations. Distinct EQE‐Current density performance are analyzed and validated by the transient EL response, which reveal the Triplet‐Triplet Annihilation (TTA) impact differently. Overall, an efficiency‐lifetime‐trade‐off have been obtained, with 60% Lifetime promotion, 3% EQE decline and 6% voltage rise. The investigation of mechanism and experimental validation provide a method in long‐lifetime and high‐efficiency device design. [ABSTRACT FROM AUTHOR]

"Fangfeng" in Chinese Materia Medica refers to the dried root of Saposhnikovia divaricata (Trucz.) Schischk. The confusion regarding the species emerged centuries ago. Various medicinal plants from the family Umbelliferae have been documented under the name Fangfeng or other similar names in different areas of China. However, the efficacy and chemical profiles of these herbs can vary widely. In recent years, studies on medicinal material markets have revealed that "ChoutaiFangfeng" and "ShiFangfeng" are sold as Fangfeng. Previous studies on the differences among these herbs were not accurate; therefore, comprehensive authentication of these species is required. Investigation of the microscopic features of the transverse sections and powders of herbs is of great significance in identifying traditional Chinese medicine. This approach offers the advantages of easy operation and rapid results. In this study, microscopic observation of cross‐sectional tissues and powders of the herbs was performed using common light microscopy and polarized light microscopy, respectively, to identify Fangfeng, ChoutaiFangfeng, and ShiFangfeng. We found that phloem, clefts, and other significant tissue characteristics can be used to distinguish Fangfeng herbs. The developed method can also be applied to distinguish counterfeits of Fangfeng. Moreover, the macroscopic and microscopic characteristics of Fangfeng and its two adulterants were determined. [ABSTRACT FROM AUTHOR]

There is an increasing attention paid to improving transparent conductive electrodes for applications in highly transparent and large area displays. We optimized top‐emitting blue organic light‐emitting diodes (TE‐BOLEDs) using hybrid cathode consisting of a thermally evaporated Mg/Ag capped with IZO. The device of cd/A/CIEy which used the hybrid cathode improved by 20% more than that with the identical organic layers and conventional Mg/Ag cathode. Meanwhile the transparency increased by 13% and sheet resistance decreased by half. Balancing the device performance, transparency and resistivities, different hybrid cathode structure could meet various requirements. [ABSTRACT FROM AUTHOR]

Highly efficient tandem blue OLEDs based on fluorescent materials were developed for quantum dot OLED applications. We optimize the optical micro‐cavity structure for maximal efficiency, and the dependence of luminescence on the thickness uniformity is theoretically and experimentally confirmed with two different type of blue emitters. We also demonstrate that the selection of charge generation layer (CGL) and electrontransporting material adjacent to CGL have significant impact on the electroluminescence performance of the tandem blue OLEDs. Here, a two‐stack tandem blue OLED achieves a current efficiency of 13.3 cd/A with a CIE coordinate of (0.137, 0.047) and a blue index (BI) of 287, which is approximately 1.7 times higher than that of single unit. [ABSTRACT FROM AUTHOR]

A set of top‐emitting OLED with wide‐color gamut and high‐efficiency were successfully fabricated by using 3‐stacked B/RG/B tandem structure and color filter. Optimization of MgAg and Indium Zinc Oxide (IZO) composite structure made the devices with IZO served as capping layer almost identical to the devices with conventional organic capping layer. On the whole, they exhibited 90% color gamut coverage of the ultra‐high definition display standard BT.2020, while maintaining high efficiency of red 15.5 cd/A, green 26.6 cd/A, blue 3.5 cd/A. The impressive properties make them applicable to a variety of occasions, such as the medium‐sized notebook monitors, emerging high‐specification virtual and augmented reality (VR/AR) technologies, and special medical displays. [ABSTRACT FROM AUTHOR]

Organic light‐emitting diodes (OLEDs) have been regarded as one of the most promising technologies for future displays, and efficient encapsidation technology is the key to improve lifetime of OLED devices. Herein, we explore the injitience of different Ultraviolet (UV) lamps (High pressure mercury UV lamp (hereinafter abbreviated as mercury UV lamp) and Light Emitting Diode (LED) UV lamp) on OLED encapsulation filler curing efficiency and probe into the inherent causes. The results show that mercury UV lamp presents a higher filler curing efficiency than LED UV lamp, attributing to its wider light spectrum. Unfortunately, the short wavelength below 325 nm in mercury UV lamp light can cause fast deterioration for filler film. Obviously, this discovery has important guiding effect in optimized design of encapsulation process. [ABSTRACT FROM AUTHOR]

There is an increasing attention paid to improving transparent conductive electrodes for applications in highly transparent and large size displays. We optimized top‐emitting organic light‐emitting diodes (TE‐OLEDs) using high resistance IZO as a short reduction layer to reduce leakage current through a shorting defect. Leakage current devices have decreased by 5% and brightness decreased by 11% less than the devices with the identical organic layers and standard IZO cathode. [ABSTRACT FROM AUTHOR]

The purposeful modulation of the optoelectronic properties was realised on the basis of a series of the large, conjugated, phosphine oxide hosts 9,9-bis-{4′-[2-(diphenylphosphinoyl)phenoxy]biphenyl-4-yl}-9 H-fluorene (DDPESPOF), 9,9-bis-{3′-(diphenylphosphinoyl)-4′-[2-(diphenylphosphinoyl)phenoxy]biphenyl-4-yl}-9 H-fluorene (DDPEPOF), 9-[4′-(9-{4′-[2-(diphenylphosphoryl)phenoxy]biphenyl-4-yl}-9 H-fluoren-9-yl)biphenyl-4-yl]-9 H-carbazole (DPESPOFPhCz) and 9-[4′-(9-{3′-(diphenylphosphoryl)-4′-[2-(diphenylphosphoryl)phenoxy]biphenyl-4-yl}-9 H-fluoren-9-yl)biphenyl-4-yl]-9 H-carbazole (DPEPOFPhCz). The last two are quaternary with fluorenyls as linking bridges, diphenylphosphine oxide (DPPO) moieties as electron acceptors and diphenylethers and carbazolyls as two different kinds of electron donors. Owing to the fine-organised molecular structures and the mixed indirect and multi-insulating linkages, all of these hosts achieve the same first triplet energy levels (T1) of 2.86 eV for exothermic energy transfer to phosphorescent dopants. The first singlet energy levels (S1) and the carrier injection/transportation ability of the hosts were accurately modulated, so that DPESPOFPhCz and DPEPOFPhCz revealed extremely similar optoelectronic properties. However, the T1 state of the former is localised on fluorenyl, whereas the carbazolyl mainly contributes to the T1 state of the latter. A lower driving voltages and much higher efficiencies of the devices based on DPESPOFPhCz indicated that the chromophore-localised T1 state can suppress the quenching effects through realising independent contributions from the different functional groups to the optoelectronic properties and the embedding and protecting effect on the T1 states by peripheral carrier transporting groups. [ABSTRACT FROM AUTHOR]

Layered nickel silicate nanoflowers (NSFs) with a hierarchical nanostructure have been successfully fabricated by a template-free solvothermal method. The as-prepared nanoflowers were composed of many interconnected edge-curving lamellae with a thickness of about 15 nm and had a high specific surface area (279 m2 g−1) and large pore volume (0.67 cm3 g−1). The highly dispersed small silver nanoparticles (AgNPs) were immobilized on the surface of NSFs through the in situ reduction of Ag+ by Sn2+. The AgNP/NSF nanocomposites showed a high performance in the catalytic reduction of 4-nitrophenol. In particular, there was no visible decrease in the catalytic activity of the reused catalysts even after being recycled four times. The as-prepared AgNP/NSF nanocomposites might be an excellent catalyst owing to their availability, formability, chemical and thermal stability, and high specific surface area. [ABSTRACT FROM AUTHOR]

The article presents a study on the impact of implementing black-box warnings (BBW)-based alerts regarding medications in electronic health records on physician adherence to the warnings. It evaluates the effect of delivering such alerts in outpatients in an electronic health record on the level of adherence among clinicians through multivariate analysis. It reveals that computerized order entry of prescribing alerts about BBWs did not improve physicians' overall adherence to such warnings.