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951.
952.
Tae‐Yeon Oh Nam‐Su Kang Ki‐Young Dong Seongpil Chang Jung‐Ho Park Shin‐Woo Jung Seung‐Jun Lee Byeong‐Kwon Ju 《固体物理学:研究快报》2011,5(3):101-103
We fabricated 6,13‐bis(triisopropylsilylethynyl)–pentacene (TIPS–pentacene) thin film transistors using a direct metal transfer method. Using different metals, such as Au and Ag ink, electrode patterns are formed from the relief region of the polymer mold. TIPS–pentacene TFTs using the Ag ink transfer method show a similar performance to those using the Au metal transfer method. This method has advantages over the Au metal transfer method because it does not require vacuum equipment and a dry etching process. The self‐assembled monolayer (SAM) treated device exhibits a carrier mobility of 9.5 × 10–2 cm2/V · s, and an on/off ratio of 4.6 × 104. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
953.
We amplified acoustic evanescent waves using metamaterial slabs with a negative effective density. For the amplifying effect of the slab to overcome the dissipation, it is necessary that the imaginary part of the effective density is much smaller than the real part, a condition not satisfied so far. We report the construction of membrane-based two-dimensional negative-density metamaterials which exhibited remarkably small dissipation. Using a slab of this metamaterial we realized a 17-fold net amplitude gain at a remote distance from the evanescent wave source. Potential applications include acoustic superlensing. 相似文献
954.
955.
We demonstrate a sliding-frequency mode-locked (SFM) erbium fiber laser generating 20 ps pulses with center wavelengths rapidly sweeping across a spectral range of 50 nm. Excess optical nonlinearity in the laser cavity leads to multipulsing, with a tendency to tight pulse bunching (<3 ns) at the fundamental cavity frequency of 25 MHz. The addition of a parallel optical delay line, with a path difference equal to a rational fraction of the cavity length, distributes the pulses uniformly across the entire cavity and achieves a harmonic SFM up to 1 GHz. The result establishes cavity nonlinearity as a critical design parameter for picosecond wavelength-swept lasers. 相似文献
956.
We report on lasing action from colonies of Escherichia coli bacteria that are genetically programmed to synthesize the green fluorescent protein (GFP). When embedded in a Fabry-Perot type cavity and excited by ns-pulses of blue light (465 nm), the bacteria generate green laser emission (~520 nm). Broad illumination of pump light yields simultaneous lasing over a large area in bacterial colonies. 相似文献
957.
Lee SS Greig IR Vocadlo DJ McCarter JD Patrick BO Withers SG 《Journal of the American Chemical Society》2011,133(40):15826-15829
The effects of fluorine substitution at the C-5 center of pyranosyl fluorides on the reactivity at the C-1 anomeric center was probed by studying a series of 5-fluoroxylosyl fluoride derivatives. X-ray structures of their per-O-acetates detailed the effects on the ground-state structures. First-order rate constants for spontaneous hydrolysis, in conjunction with computational studies, revealed that changes in the stereochemistry of the 5-fluorine had minimal effects on the solvolysis rate constants and that the observed rate reductions were broadly similar to those caused by additional fluorine substitution at C-1 but significantly less than those due to substitution at C-2. Differences in the trapping behavior of 5- versus 2-fluoro-substituted glycosyl fluorides with α- and β-glycosidases arise more from differences in steric effects and hydrogen-bonding interactions than from intrinsic reactivity differences. 相似文献
958.
Kyung-In JangByung-Kwon Min Jongwon Seok 《Journal of magnetism and magnetic materials》2011,323(10):1324-1329
A model that considers the mutual interaction between particles and the external field in a magnetorheological (MR) fluid is proposed. The model predicts the magnetization, interaction energy density, and shear stress against an imposed strain along the planar direction under a uniform magnetic field. Using the Lekner summation method, slowly convergent magnetization functions are transformed into rapidly convergent ones. By applying the proposed model to an application suitable for commercial clutches and dampers working in direct shear mode, it is revealed that the mean magnetization vector and the associated functional quantities of the MR fluid behave harmonically with respect to the imposed shear strain. 相似文献
959.
Jae Gon Kim On-Yu Kang Sang Mee Kim Guldana Issabayeva In Seok Oh Yaeji Lee Won Hyung Lee Hwan Jung Lim Seong Jun Park 《Molecules (Basel, Switzerland)》2020,25(23)
Herein, we describe novel pentafluorosulfanyl (SF5) group-containing meta-diamide insecticides. For the facile preparation of the SF5-based compounds 4a–d, practical synthetic methods were applied. Among newly synthesized compounds, 3-benzamido-N-(2,6-dimethyl-4-(pentafluoro-λ6-sulfanyl)phenyl)-2-fluorobenzamide 4d showed (i) a high insecticidal activity, (ii) an excellent selectivity to insects, and (iii) good levels of water solubility and log P values. In this study, we demonstrated that the pentafluorosulfanyl moiety could serve as an attractive functionality for the discovery of a new scope of crop-protecting agents. 相似文献
960.
Pai Liu Weiqiang Fu Peter Verwilst Miae Won Jinwoo Shin Zhengxu Cai Bin Tong Jianbing Shi Yuping Dong Jong Seung Kim 《Angewandte Chemie (International ed. in English)》2020,59(22):8435-8439
Heteroatom‐containing spiropolymers were constructed in a facile manner by a catalyst‐free multicomponent spiropolymerization route. P1a2b as the most potent of these spiropolymers, demonstrates cluster‐triggered emission resulting from strong interactions with the MDM2 protein. By preventing the anti‐apoptotic p53/MDM2 interaction, P1a2b triggers apoptosis in cancerous cells, while demonstrating a good biocompatibility and non‐toxicity in non‐cancerous cells. The combined results from solution and cell‐based cluster‐triggered emission studies, docking, protein expression experiments and cytotoxicity data strongly support the MDM2‐binding hypothesis and indicate a potential application as a fluorescent cancer marker as well as therapeutic for this spiropolymer. 相似文献