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91.
This study compared stabilities of tocopherols and lutein in oil extracted from roasted mustard seeds (RMSO) with those in
oil from unroasted seeds (URMSO) during oil oxidation at 60°C in the dark for 12 days. Tocopherols and lutein were determined
by high performance liquid chromatography, and the oil oxidation was monitored with conjugated dienoic acid (CDA) content
and fatty acid composition by gas chromatography. The rate of CDA increase was lower in RMSO (0.038%/day) than in URMSO (0.047%/day)
during 12-day oxidation in the dark, with little change in fatty acid composition in both oils. Tocopherols and lutein were
more abundant in RMSO, initially 465.38 and 100.55 μg/g, respectively, than in URMSO, and their stability was higher in RMSO
(−4.63 and −5.94%/day of degradation in tocopherols and lutein, respectively) than in URMSO during 12-day oxidation of oil,
both of which contributed to higher autoxidative stability of RMSO than URMSO. 相似文献
92.
El-Tahawy Moustafa Jenei Péter Kolonits Tamás Han Gigap Park Hyeji Choe Heeman Gubicza Jenő 《Metallurgical and Materials Transactions A》2020,51(7):3447-3460
Metallurgical and Materials Transactions A - The tensile and compressive behaviors of 316L stainless steel at room temperature were compared. The differences between the stress–strain... 相似文献
93.
Ravi Shanker Seungse Cho Ayoung Choe Minsoo P. Kim Ziyauddin Khan Saewon Kang Hyunhyub Ko 《Advanced functional materials》2019,29(39)
Flexible alternating‐current electroluminescent (ACEL) devices have attracted considerable attention for their ability to produce uniform light emission under bent conditions and have enormous potential for applications in back lighting panels, decorative lighting in automobiles, and panel displays. Nevertheless, flexible ACEL devices generally require a high operating bias, which precludes their implementation in low power devices. Herein, solution‐processed La‐doped barium titanate (BTO:La) nanocuboids (≈150 nm) are presented as high dielectric constant (high‐k) nanodielectrics, which can enhance the dielectric constant of an ACEL device from 2.6 to 21 (at 1 kHz), enabling the fabrication of high‐performance flexible ACEL devices with a lower operating voltage as well as higher brightness (≈57.54 cd m?2 at 240 V, 1 kHz) than devices using undoped BTO nanodielectrics (≈14.3 cd m?2 at 240 V, 1 kHz). Furthermore, a uniform brightness across the whole panel surface of the flexible ACEL devices and excellent device reliability are achieved via the use of uniform networks of crossaligned silver nanowires as highly conductive and flexible electrodes. The results offer experimental validation of high‐brightness flexible ACELs using solution‐processed BTO:La nanodielectrics, which constitutes an important milestone toward the implementation of high‐k nanodielectrics in flexible displays. 相似文献
94.
Nanoparticle‐Enhanced Silver‐Nanowire Plasmonic Electrodes for High‐Performance Organic Optoelectronic Devices 下载免费PDF全文
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
95.
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
96.
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
97.
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
98.
Rational and Facile Construction of 3D Annular Nanostructures with Tunable Layers by Exploiting the Diffraction and Interference of Light 下载免费PDF全文
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
99.
ASTUDYOFCARBIDEGROWTHINMAR-M247LCALLOYBYDIRECTIONALSOLIDIFICATIONMETHODJ.HLee;J.Chen;S.J.Choe;Y.T.LeeandH.M.Kim(HighTemperatu... 相似文献
100.
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