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151.
Kyungsik Ock Gabsoo Jang Yongrae Roh Sunghoon Kim Jaeho Kim Kwangnak Koh 《Microchemical Journal》2001,70(3)
In this study, we have fabricated Cu2+ ion sensor using a squarylium dye (SQ-dye) containing polymeric thin-film. Surface Plasmon Resonance (SPR) was used as a signal amplifier to achieve high sensitivity and large linear dynamic range for detection of Cu2+ ion. High selectivity to Cu2+ ion was obtained by the effective electro-static interaction between SQ-dye and Cu2+ ion in the polymeric film. The optimal analytical condition of high selectivity and sensitivity in the wider linear dynamic range obtained in this study may be a result of the cooperative ‘hard-soft’ metal ion-ligand interaction and effective detection of refractive index changes by the complexation of Cu2+ ion and SQ-dye in SPR measurement. Among 10 different alkali metal, alkaline earth metal, and transition metal ions, SQ-dye in poly(vinylchloride)–poly(vinyl acetate)–poly(vinyl alcohol) (PVC–PVAc–PVA) copolymer film showed the highest selectivity to Cu2+ ion. Although the interaction between SQ-dye and metal ions has not been well understood, both cooperative ‘hard-soft’ metal ion-ligand interaction and size-selective recognition of Cu2+ ion to SQ-dye may contribute to high selectivity. Furthermore, additional sensitivity in the detection of Cu2+ ion by SPR was obtained by matching the wavelength of probing radiation of SPR and absorption maximum of SQ-dye at 675 nm, which allow to detect small changes in the refractive index by complex formation on the sensing surface. This result may apply in development of the Cu2+ ion selective sensor for medical, biochemical, and environmental applications. 相似文献
152.
Jang Junhyuk Kim Tack-Jin Eun Hee-Chul Kim Gha-Young Lee Sungjai 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):649-654
Journal of Radioanalytical and Nuclear Chemistry - U recovery test was performed on a Zn-U alloy to confirm the feasibility of Zn as an alternative cathode material. An evaporation test of pure Zn... 相似文献
153.
The purpose of this paper is to generalize Yalçin's result [Trans. Amer. Math. Soc. 352 , 2689–2700 (2000)] from tori to solvmanifolds. As a result, we prove that if (?p)r acts freely on a solvmanifold M of dimension n, then r ≤ n (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
154.
We construct infinitely many three-bridge links each of which admits infinitely many three-bridge spheres up to isotopy. 相似文献
155.
Optical and Electrical Properties of Ferroelectric SBN Thin Films Prepared by Sol-Gel Process 总被引:1,自引:0,他引:1
Junmo Koo Jae Hyeok Jang Byeong-Soo Bae 《Journal of Sol-Gel Science and Technology》2000,19(1-3):611-614
Strontium barium niobate thin films were prepared by sol-gel method on various substrates using an improved process, two-step heating process. The two-step heating process applies an additive heat-treatment before crystallization for enhancement of the densification and the nucleation of films. Also, highly c-axis oriented SBN thin films with various compositions were obtained on MgO(100) and Pt(100)/MgO(100) substrates. Their optical and electrical properties such as optical propagation loss, refractive index, P-E hysteresis, and dielectric constant, were characterized as a function of the film composition. 相似文献
156.
Jaehyun Moon Yong-Hae Kim Choong-Heui Chung Su-Jae Lee Dong-Jin Park Yoon-Ho Song 《Applied Surface Science》2008,254(20):6422-6427
The growth of Si oxide by means of a cyclic radio-frequency (rf) plasma oxidation process has been explored in a low temperature range of 100-200 °C. The growth mechanism exhibits Cabrera-Mott (CM) oxidation, that is, the transport of mobile ionic species is assisted by an electric field. The low activation energy of 0.3 eV is attributed to the small size of O− and the assistance of the electric field. The oxide becomes off-stoichiometric as one approaches to the exterior surface of the oxide layer. 相似文献
157.
158.
159.
Yinam Li Tae‐Hoon Kim Qinghua Zhao Euh‐Kyung Kim Seung‐Hon Han Yun‐Hi Kim Jin Jang Soon‐Ki Kwon 《Journal of polymer science. Part A, Polymer chemistry》2008,46(15):5115-5122
We have designed and synthesized a new polymer, which could be used in the organic thin film transistor (OTFT). Poly[2,6‐bis(3′‐dodecythiophene‐2′‐yl)anthracene] (PDTAn), which is composed with anthracene moiety and dodecyl alkyl thiophene, was synthesized by oxidative polymerization using iron (III) chloride. The mole ratio of FeCl3 and monomer (4.2:1), keeping low temperature during the initiation reaction, amount of solvent, and dropping order were very important for oxidative polymerization without crosslinking. The molecular weight of the polymer (Mw) was measured to be 40,000 with 2.85 of polydispersity index by GPC. The physical and optical properties of the polymer were characterized by differential scanning calorimetry (DSC), cyclic voltammetry (CV), and optical absorption and photoluminescence (PL) spectroscopy. A field‐effect mobility of 1.1 × 10?4 cm2 V?1 S?1, a current on/off ratio of 105, and the Vth at ?15.2 V had been obtained for OTFTs using this polymer semiconductor by solution coating. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5115–5122, 2008 相似文献
160.
Journal of Visualization - An unbalanced panel is a dataset in which at least one subject is not observed some times. Moreover, each subject is recorded with irregular periods and intervals.... 相似文献