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91.
Nanoparticle‐Enhanced Silver‐Nanowire Plasmonic Electrodes for High‐Performance Organic Optoelectronic Devices
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Taehyo Kim Saewon Kang Jungwoo Heo Seungse Cho Jae Won Kim Ayoung Choe Bright Walker Ravi Shanker Hyunhyub Ko Jin Young Kim 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
Improved performance in plasmonic organic solar cells (OSCs) and organic light‐emitting diodes (OLEDs) via strong plasmon‐coupling effects generated by aligned silver nanowire (AgNW) transparent electrodes decorated with core–shell silver–silica nanoparticles (Ag@SiO2NPs) is demonstrated. NP‐enhanced plasmonic AgNW (Ag@SiO2NP–AgNW) electrodes enable substantially enhanced radiative emission and light absorption efficiency due to strong hybridized plasmon coupling between localized surface plasmons (LSPs) and propagating surface plasmon polaritons (SPPs) modes, which leads to improved device performance in organic optoelectronic devices (OODs). The discrete dipole approximation (DDA) calculation of the electric field verifies a strongly enhanced plasmon‐coupling effect caused by decorating core–shell Ag@SiO2NPs onto the AgNWs. Notably, an electroluminescence efficiency of 25.33 cd A?1 (at 3.2 V) and a power efficiency of 25.14 lm W?1 (3.0 V) in OLEDs, as well as a power conversion efficiency (PCE) value of 9.19% in OSCs are achieved using hybrid Ag@SiO2NP–AgNW films. These are the highest values reported to date for optoelectronic devices based on AgNW electrodes. This work provides a new design platform to fabricate high‐performance OODs, which can be further explored in various plasmonic and optoelectronic devices. 相似文献
92.
Ilhwan Ryu Geunpyo Choe Hyemin Kwon Dajung Hong Sanggyu Yim 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(20):2207270
It is substantially challenging for transition metal oxide nanoparticle (NP)-based electrodes for supercapacitors to achieve high transparency and large capacity simultaneously due to the inherent trade-off between optical transmittance (T) and areal capacitance (CA). This study demonstrates how this trade-off limitation can be overcome by replacing some electrode NPs with transparent tin oxide (SnO2) NPs. Although SnO2 NPs are non-capacitive, they provide effective paths for charge transport, which simultaneously increase the CA and T550nm of the manganese oxide (Mn3O4) NP electrode from 11.7 to 13.4 mF cm−2 and 82.1% to 87.4%, respectively, when 25 wt% of Mn3O4 are replaced by SnO2. The obtained CA values at a given T are higher than those of the transparent electrodes previously reported. An energy storage window fabricated using the mixed-NP electrodes exhibits the highest energy density among transparent supercapacitors previously reported. The improved energy density enables the window to operate various electronic devices for a considerable amount of time, demonstrating its applicability in constructing a reliable and space-efficient building-integrated power supply system. 相似文献
93.
This paper proposes a new temporal error concealment algorithm in H.264 video sequences based on scene change detection and PCA model. In order to detect scene change, dynamic threshold and image similarity metric are presented using coding prediction mode and DCT AC energy in H.264 baseline. UPCA (Updated PCA) model is presented by combining the scene change feature with Index transformation-Buffer updating approach. The lost images are concealed by Projection onto Convex Sets algorithm with UPCA model. Experimental results show that the proposed algorithm can achieve better error concealment performance for the higher motion and the frequent scene change, compared with the related method. 相似文献
94.
Choe Jaehoon Kwon Youngwoon Kim Yeongdae Song Hyun-Seob Song Kwang Ho 《Korean Journal of Chemical Engineering》2003,20(2):268-272
A mixing device composed of a micron scale flow channel was applied as a continuous reactor to control exothermic reaction
heat and to increase the product yield, in a synthesis of a pharmaceutical intermediate of quinolone antibiotics. The model
reaction featured a fast reaction rate, high heat generation, and impurity formation due to a prolonged contact time between
reactants and products. Using the micromixer reactor, the reaction heat was efficiently removed so that virtually no impurities
were produced during the reaction. A product yield comparable to the theoretical value was achieved in a single micromixer
unit. Optimum operating conditions were acquired from a statistical method by using factorial design, which was also verified
by a CFD calculation. 相似文献
95.
Rational and Facile Construction of 3D Annular Nanostructures with Tunable Layers by Exploiting the Diffraction and Interference of Light
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This paper reports a rational and facile approach to fabricating arrays of 3D annular nanostructures with tunable layers by utilizing the diffraction and interference of UV light. Based on discretized Fresnel bright spots and standing waves formed within a photoresist film, the structures with nanoscale features are realized using simple, conventional photolithography. The 3D annular nanostructures are produced in arrays of single‐, double‐, and triple‐layered ring structures with the height of single layer on a 100 nm scale. The structural formation process and features of the nanostructures are analyzed and explained through 3D modeling that integrates the effects of both UV exposure dose and chemical kinetics. The approach to generating 3D annular nanostructures with tunable layers and discrete heights can be adapted for various applications that require the 3D structures fabricated over a large area with high throughput. 相似文献
96.
ASTUDYOFCARBIDEGROWTHINMAR-M247LCALLOYBYDIRECTIONALSOLIDIFICATIONMETHODJ.HLee;J.Chen;S.J.Choe;Y.T.LeeandH.M.Kim(HighTemperatu... 相似文献
97.
The dynamic behavior of dispersion-type tubular reactors, referred to as finite and truncated models depending on the boundary
condition representations at the reactor exit, was investigated through numerical simulations. It was found that the dynamic
behavior of the two models can be identical or different depending on how thePéclet number changes. 相似文献
98.
Chang-Yong Jo Neil Jones Seung-Joo Choe David Knowles 《Metals and Materials International》1998,4(5):1017-1025
The second generation DS alloy, CM186LC is used in the as-cast and double aged condition which has creep-rupture properities
equivalent to the first generation single crystal alloys CMSX-2 and CMSX-3. In production, cast vane components have to be
subjected to a brazing treatment for joining into pairs. The effect of the brazing treatment and modified brazing treatment
(heat treatment) on mechanical properities at high temperature was studied in accordance with microstructure. Brazing treatments
gave no effect on tensile properities and creep failure mode of DS CM186LC, although a small decrease in stress-rupture life
was observed. Creep failure was related to the solidified microstructure. Creep cracks began at the grain boundary normal
to the applied stress, especially at the γ/γ’ eutectic phase on grain boundaries. Most of γ/γ’ eutectics which had solidified
at the last stage of casting, had microporosity which became a crack initiation site during creep. MC carbide reaction with
the matrix γ was observed in the creep failed specimens. 相似文献
99.
Approaches to predict da/dN-àK for environmental situations; including empirical interpolative equations, linear superposition
of mechanical fatigue and time-based environmental cracking, and mechanism-based models; are presented. For several material-environment
systems, these models were incorporated in fracture mechanics life prediction methods, and successes have been reported in
evaluating the corrosion fatigue contribution. Considerable uncertainties are, however, associated with these models. The
linear superposition analysis is emphasized; material-environment systems that are severely environment-sensitive should be
adequately described by this method. Direct and indirect methods exist to define time-based crack growth rates for use in
linear superposition predictions of da/dN. The linear superposition approach is effective, but only for those cases where
KISCC is high relative to typical flawed component stress intensity levels. Empirical curve-fit models require an extensive environmental
crack growth rate data base, which are costly to develop, and are effective for interpolations but not predictions of fatigue
crack growth data. Mechanism-based models for broad predictions of cycle-time dependent da/dN versus àK, and other variables
such as frequency or hold time, are in an infant state. 相似文献
100.
Sangcheol Kim Won Ho Jo Junkyung Kim Soon Ho Lim Chul Rim Choe 《Journal of Materials Science》1999,34(1):161-168
In an effort to investigate the effect of the crystalline morphology of a poly(butylene terephthalate) (PBT) phase on the toughening of PBT/epoxy blends, the blends, having different degrees of perfectness of the PBT crystalline phase, were prepared by blending PBT and epoxy at various temperatures ranging from 200 to 240 °C. As the blending temperature decreases, the degree of perfectness of the PBT crystalline phase increases as a result of the increase of crystal growth rate. For PBT/epoxy blends, the change in crystalline morphology induced by processing may be the most important cause for the dependency of the fracture energy on blending temperatures. It has been found that PBT phases with a well-developed Maltese cross are most effective for epoxy toughening. This dependency reveals the occurrence of a phase transformation toughening mechanism. Also, the higher relative enhancement of fracture energy of a higher molecular weight epoxy system is further indirect evidence for a phase transformation toughening mechanism. Some other toughening mechanisms observed from the fracture surfaces, such as crack bifurcation, crack bridging, and ductile fracture of PBT phases, have been found to also be affected by the blending temperatures. 相似文献