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71.
Photo‐Stable Organic Thin‐Film Transistor Utilizing a New Indolocarbazole Derivative for Image Pixel and Logic Applications 下载免费PDF全文
Ji Hoon Park Hee Sung Lee Soohyung Park Sung‐Wook Min Yeonjin Yi Cheon‐Gyu Cho Jiwon Han Tae Woong Kim Seongil Im 《Advanced functional materials》2014,24(8):1109-1116
Small molecule pentacene layer has been a representative among many organic thin‐film transistor (OTFT) channels with decent p‐type mobilities, but it is certainly light‐sensitive due to its relatively small highest occupied molecular orbital‐lowest unoccupied molecular orbital (HOMO‐LUMO) gap (1.85 eV). Although a few other small molecule‐based layers have been reported later, their photo‐stabilities or related device applications have hardly been addressed. Here, a new photostable organic layer is reported, heptazole (C26H16N2), which has almost the same HOMO level as that of pentacene but with a higher HOMO‐LUMO gap (≈2.95 eV). This heptazole OTFT displays a decent mobility comparable to that of conventional amorphous Si TFTs, showing good photostability unlike pentacene OTFTs. An image pixel driving the photostable heptazole OTFT connected to a pentacene/Al Schottky photodiode is demonstrated. This heptazole OTFT also conveniently forms a logic inverter coupled with a pentacene OTFT, sharing Au for source/drain. 相似文献
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Hyun‐Ju Yang Ji‐Hyeon Lee Ka‐Yeon Lee Kyung Bin Song 《International Journal of Food Science & Technology》2017,52(2):398-403
To develop a value‐added product, we used the under‐utilised seaweed Undaria pinnatifida as a source material for the fabrication of a biodegradable film by extracting U. pinnatifida protein (UPP). UPP/gelatine composite films with different constituent ratios were prepared. In addition, the UPP/gelatine composite films containing vanillin (0.05%, 0.1% and 0.5%) were prepared as antimicrobial packaging material. To evaluate the utility of the UPP composite film containing 0.5% vanillin as food packaging material, smoked chicken breast samples inoculated with Escherichia coli were packed with the film and stored at 4 °C for 10 days. It was observed that packaging of smoked chicken breast with the UPP composite film containing vanillin decreased the population of the inoculated E. coli by 1.12 log CFU g?1 compared with that in the control sample. Thus, the UPP/gelatine composite film with added vanillin can be utilised as a packaging material for smoked chicken breast. 相似文献
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Lee HR Lee KY Park NC Shin JS Moon DJ Lee BG Kim YC 《Journal of nanoscience and nanotechnology》2006,6(11):3396-3398
The performance of Ni/delta-Al2O3 catalyst in propane autothermal reforming (ATR) for hydrogen production was investigated in the present study. The catalysts were characterized using XRD, TEM, and SEM. The activity of the Ni/delta-Al2O3 catalyst manufactured by the water-alcohol method was better than those of the catalysts manufactured by the impregnation and chemical reduction methods. The Ni/delta-Al2O3 catalysts were modified by the addition of promoters such as Mg, La, Ce, and Co, in order to improve their stability and yield. Hydrogen production was the largest for the Ni-Co-CeO2/Al2O3, catalyst. 相似文献
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Kwang Myung Jeon Su Yeon Park Chan Jun Chun Nam In Park Hong Kook Kim 《ETRI Journal》2017,39(3):398-405
In this paper, an artificial stereo extension method that creates stereophonic sound from a mono sound source is proposed. The proposed method first trains deep neural networks (DNNs) that model the nonlinear relationship between the dominant and residual signals of the stereo channel. In the training stage, the band‐wise log spectral magnitude and unwrapped phase of both the dominant and residual signals are utilized to model the nonlinearities of each sub‐band through deep architecture. From that point, stereo extension is conducted by estimating the residual signal that corresponds to the input mono channel signal with the trained DNN model in a sub‐band domain. The performance of the proposed method was evaluated using a log spectral distortion (LSD) measure and multiple stimuli with a hidden reference and anchor (MUSHRA) test. The results showed that the proposed method provided a lower LSD and higher MUSHRA score than conventional methods that use hidden Markov models and DNN with full‐band processing. 相似文献
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Dong‐Ha Kim Sang‐Ho Lee Se‐Kook Park Min‐Jung Choi Kyoung‐Hee Shin Chang‐Su Jin Yun Jung Lee Sun‐Hwa Yeon 《国际能源研究杂志》2017,41(8):1202-1210
A cyclic ultracapacitor is a promising energy storage device that can be used for grid energy storage. The cyclic ultracapacitor combines the advantages of both ultracapacitors and flow batteries, enabling rapid charging and large‐scale energy use. To improve the electrochemical performance under the flow condition, it is necessary to find a more electrical active material and design a flow cell that minimizes the resistance. In this study, we investigate the effects of changing the ratio of the active material in a slurry electrode under various operating conditions. Slurry electrodes were prepared with different ratios of active material and conductive additive but with a fixed electrolyte amount. Voltage–time curves of both a single and a stack‐flow cell in the constant‐current mode were obtained to analyze the relationship between the active materials ratio and the cell performance. Having more adsorption sites according to the active material amount is more important than increasing the electric conductivity by the conductive additive amount with regard to cell performance capabilities in a low resistance condition such as a non‐flow mode. However, higher electrical conductivity on a slurry electrode is more beneficial to improve the electrochemical performance in the stack‐flow mode, which has harsh resistance levels. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
80.
Kotesh Kumar Mandari Anil Kumar Reddy Police Jeong Yeon Do Misook Kang Chan Byon 《International Journal of Hydrogen Energy》2018,43(4):2073-2082
In this experimental studies, we report the synthesis of TiO2 co-doped by both cationic and anionic sites by simple sol-gel based method. All the prepared samples exhibit the anatase crystalline morphology however, showed lattice distortion caused by the displacement of Ti4+ sites by Gd3+. The improved visible absorption is witnessed by the Gd and N co-doping with an assured redshift in the absorption edge. The N and Gd displacement inside TiO2 lattice accompanied by the creation of OTiN and GdOTi bonds are characterized by the X-ray photoelectron spectra. The strong resonance signal by Gd4f electrons in the electron paramagnetic resonance spectroscopy further substantiate the displacement of lattice cites of TiO2 by Gd3+ ions. The longevity of the photo produced charges observed in fluorescence spectra of Gd and N co-doped TiO2 is because of the effective transfer of charges to the defect sites. The aforementioned catalysts are tested for their capacity for the H2 production from water splitting. The 2 wt% gadolinium and nitrogen co-doped TiO2 has shown 10764 μmol g?1 H2 production which is 26 times higher than the commercial Degussa P-25 catalyst. The enhanced activity for hydrogen production can be attributed to factors such as increased absorptivity under visible light and effective charge carrier separation. 相似文献