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Osan, South Korea

Kim K.H.,Korea University | An H.-M.,Osan College | Kim H.-D.,Korea University | Kim T.G.,Korea University
Nanoscale Research Letters | Year: 2013

We propose a transparent conductive oxide electrode scheme of gallium oxide nanoparticle mixed with a single-walled carbon nanotube (Ga2O3 NP/SWNT) layer for deep ultraviolet light-emitting diodes using spin and dipping methods. We investigated the electrical, optical and morphological properties of the Ga2O3 NP/SWNT layers by increasing the thickness of SWNTs via multiple dipping processes. Compared with the undoped Ga2O3 films (current level 9.9 × 10-9 A @ 1 V, transmittance 68% @ 280 nm), the current level flowing in the Ga2O3 NP/SWNT increased by approximately 4 × 105 times and the transmittance improved by 9% after 15 times dip-coating (current level 4 × 10-4 A at 1 V; transmittance 77.0% at 280 nm). These improvements result from both native high transparency of Ga2O3 NPs and high conductivity and effective current spreading of SWNTs. © 2013 Kim et al.

Park S.,Korea University | Lee J.H.,Korea University | Kim H.-D.,Korea University | Hong S.M.,Korea University | And 3 more authors.
Physica Status Solidi - Rapid Research Letters | Year: 2013

The authors report the resistive switching characteristics of sol-gel based ZnO nanorods (NRs) fabricated on flexible substrates. A resistance ratio of 10, endurance of over 100 cycles, and narrower dispersion in the ON/OFF voltages and resistances compared to ZnO thin-film devices are demonstrated. Furthermore, the resistive switching characteristics on flexible substrates are maintained under severe substrate bending because of the ductile properties of the nanorods. Devices composed of the Au/sol-gel based NRs/Au structure have the potential for low-temperature flexible nonvolatile memory applications. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An I.-S.,Konkuk University | An S.,Konkuk University | Kwon K.J.,Konkuk University | Kim Y.J.,Osan College | Bae S.,Konkuk University
Oncology Reports | Year: 2013

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer insensitive to chemotherapy. Efforts are, therefore, directed toward understanding the molecular mechanisms of chemotherapy insensitivity and the development of new anticancer drugs. Ginsenoside Rh2, one of the components in ginseng saponin, has been shown to have antiproliferative effect on human NSCLC cells and is being studied as a therapeutic drug for NSCLC. microRNAs (miRNAs) are small, non-coding RNA molecules that play a key role in cancer progression and prevention. However, the miRNA portrait of ginsenoside Rh2-treated NSCLC cells has not yet been studied. In this study, we identified a unique set of changes in the miRNA expression profile in response to Rh2 treatment in the human NSCLC cell line A549. Using miRNA microarray analysis, we identified 44 and 24 miRNAs displaying changes in expression greater than 2-fold in Rh2-treated A549 cells. In addition, using an miRNA target prediction program, we discovered that these miRNAs are predicted to have several target genes related to angiogenesis, apoptosis, chromatic modification, cell proliferation and differentiation. Thus, these results may assist in the better understanding of the anticancer mechanism of Rh2 in NSCLC.

Kim H.-D.,Korea University | Kim H.-D.,Sejong University | Kim K.H.,Korea University | An H.-M.,Korea University | And 2 more authors.
Journal of Physics D: Applied Physics | Year: 2015

Charge-trap flash (CTF) memory using a zirconium nitride (ZrN)-based memristor switch (MRS) is demonstrated for next-generation nonvolatile memory. This device consists of a metal/MRS/nitride/oxide/silicon (M/MRS/N/O/S) structure so that electrical transport via the ZrN-based MRS layer can be utilized. Compared to previous oxide materials used as conduction paths, the proposed CTF device with a ZrN-based MRS exhibits a faster program/erase switching speed (20 ns/7 ns), along with comparable endurance and retention properties. © 2015 IOP Publishing Ltd.

Yun M.J.,Korea University | Kim H.-D.,Korea University | Kim K.H.,Korea University | Sung H.J.,Korea University | And 4 more authors.
Thin Solid Films | Year: 2013

In this paper, we report a transparent conductive oxide electrode scheme working for ultraviolet light-emitting diodes based on indium tin oxide (ITO)-rod and a single walled carbon nanotube (SWCNT) layer. We prepared four samples with ITO-rod, SWCNT/ITO-rod, ITO-rod/SWCNT, and SWCNT/ITO-rod/SWCNT structures for comparison. As a result, the sample with SWCNT/ITO-rod/SWCNT structures showed the highest transmittance over 90% at 280 nm and the highest Ohmic behavior (with sheet resistance of 5.33 kΩ/□) in the current-voltage characteristic curves. © 2013 Elsevier B.V.

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