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Jong‐Woon Ha Yuntae Kim Jeongkyun Roh Fei Xu Jong Il Park Jeonghun Kwak Changhee Lee Do‐Hoon Hwang 《Journal of polymer science. Part A, Polymer chemistry》2014,52(22):3260-3268
New low‐temperature curable organic/inorganic hybrid polymers were designed and synthesized as gate dielectrics for organic thin‐film transistors (OTFTs). Allyl alcohols were introduced to polyhedral oligomeric silsesquioxane (POSS) via hydrosilyation to produce an alcohol‐functionalized POSS derivative (POSS‐OH). POSS‐OH was then reacted with hexamethoxymethylmelamine at carrying molar ratios at 80 °C in the presence of a catalytic amount of p‐toluenesulfonic acid to give highly cross‐linked network polymers (POSS‐MM). The prepared thin films were smooth and hard after the thermal cross‐linking reaction and had very low leakage currents (<10?8 A/cm2) with no significant absorption over the visible spectral range. Pentacene‐based OTFTs using the synthesized insulators as gate dielectric layers had higher hole mobilities (up to 0.36 cm2/Vs) than a device using thermally cross‐linked poly(vinyl phenol) and melamine as the gate dielectric layer (0.18 cm2/Vs). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3260–3268 相似文献
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In this paper a quantum particle trapped in a finite harmonic oscillator confined in the moving interval is investigated. With a help of a suitable unitary transform, the wave functions and time-dependent energy levels are obtained. 相似文献
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Coordination‐Driven Self‐Assembly and Anticancer Potency Studies of Ruthenium–Cobalt‐Based Heterometallic Rectangles
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Dr. Nem Singh Dr. Sunphil Jang Jae‐Ho Jo Dong Hwan Kim Dae Won Park InHye Kim Dr. Hyunuk Kim Prof. Se Chan Kang Prof. Ki‐Whan Chi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(45):16157-16164
Three new cobalt–ruthenium heterometallic molecular rectangles, 1 – 3 , were synthesized through the coordination‐driven self‐assembly of a new cobalt sandwich donor, (η5‐Cp)Co[C4‐trans‐Ph2(4‐Py)2] (L ; Cp: cyclopentyl; Py: pyridine), and one of three dinuclear precursors, [(p‐cymene)2Ru2(OO∩OO)2Cl2] [OO∩OO: oxalato ( A1 ), 5,8‐dioxido‐1,4‐naphthoquinone ( A2 ), or 6,11‐dioxido‐5,12‐naphthacenedione ( A3 )]. All of the self‐assembled architectures were isolated in very good yield (92–94 %) and were fully characterized by spectroscopic analysis; the molecular structures of 2 and 3 were determined by single‐crystal X‐ray diffraction analysis. The anticancer activities of bimetallic rectangles 1 – 3 were evaluated with a 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT) assay, an autophagy assay, and Western blotting. Rectangles 1 – 3 showed higher cytotoxicity than doxorubicin in AGS human gastric carcinoma cells. In addition, the autophagic activities and apoptotic cell death ratios were increased in AGS cells by treatment with 1 – 3 ; the rectangles induced autophagosome formation by promoting LC3‐I to LC3‐II conversion and apoptotic cell death by increasing caspase‐3/7 activity. Our results suggest that rectangles 1 – 3 induce gastric cancer cell death by modulating autophagy and apoptosis and that they have potential use as agents for the treatment of human gastric cancer. 相似文献
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Yea‐Yang Su Chun‐Che Shih Lung‐Ching Chen Chun‐Ming Shih Shing‐Jong Lin 《Surface and interface analysis : SIA》2010,42(2):59-65
Wallstent has been successfully used to open up clogged peripheral arteries. Co? Cr alloy is the preferred metal for the construction of wallstent. Unfortunately, major complications such as in‐stent intimal hyperplasia,stent obstruction, and stent stricture are often reported, and these complications could be related to the metallic properties of the wallstent. In this study, the electrochemical properties of Co? Cr wires from wallstent were investigated using cyclic polarization, open‐circuit potential, potentiostatic condition, and electrochemical impedance spectroscopy. Scanning electron microscopy and X‐ray mapping were also employed to investigate the surface morphology and elemental distribution after electrochemical measurement. Results of this study showed the heterogeneous electrochemical properties of Co? Cr alloy wires that could result in severe galvanic corrosion of wallstent after implantation. Severe corrosion process could cause fracture of wallstent, resulting in localized inflammation, allergy, and thicker neointima. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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H.Y. Kwon J.H. Seok Y.Z. Wu C. Won 《Journal of magnetism and magnetic materials》2010,322(18):2742-2748
Stripe domain phase in a two-dimensional magnetic system was studied using model calculation and Monte-Carlo simulation in the spin reorientation transition (SRT) region. We find that near the SRT point the stripe domains evolve into a static spin wave structure with a fractional in-plane magnetization along the stripe direction and a fractional out-of-plane magnetization in a sinusoidal form. With increase in the uniaxial perpendicular anisotropy, both the wavelength and the height of the static spin wave increase slowly until the saturation of the wave height, after which the stripe width increases exponentially with the magnetic anisotropy. Our theoretical result is in good agreement with experimental observations. 相似文献
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