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101.
Sydulu Singu Bal Srinivasan Palaniappan Yoon Kuk Ro 《Journal of Solid State Electrochemistry》2016,20(12):3447-3457
Journal of Solid State Electrochemistry - Nanocomposites consisting of the conducting polymer, polyaniline (PANI), and multiwalled carbon nanotubes (MWNT) were prepared by in situ emulsion... 相似文献
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104.
Kim SH Choi WI Kim G Song YJ Jeong GH Hatakeyama R Ihm J Kuk Y 《Physical review letters》2007,99(25):256407
Metal-filled single wall carbon nanotubes (SWCNTs) are examined for possible application to conducting wires in nanoelectronics architecture. The local electronic structure of SWCNTs partially filled with cesium atoms is studied with scanning tunneling spectroscopy. The conduction and valence bands are shifted downward with two localized states in the gap at the location where the Cs atoms are filled. From a first-principles calculation, we confirm that these two gap states are bound states originating from the two lowest conduction bands. 相似文献
105.
Melfi PJ Kim SK Lee JT Bolze F Seidel D Lynch VM Veauthier JM Gaunt AJ Neu MP Ou Z Kadish KM Fukuzumi S Ohkubo K Sessler JL 《Inorganic chemistry》2007,46(13):5143-5145
A uranyl complex, the first metal complex to be formed from the cyclo[n]pyrrole series of expanded porphyrins, is formed when cyclo[6]pyrrole is treated with the uranyl cation under aerobic conditions. Spectroscopic, spectroelectrochemical, and electron spin resonance data of this species are consistent with the ligand in the complex being oxidized to an antiaromatic form. 相似文献
106.
Kim JS Lee SJ Jung JH Hwang IC Singh NJ Kim SK Lee SH Kim HJ Keum CS Lee JW Kim KS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(11):3082-3088
The Hinsberg test to recognize the type of amine (1 degrees -3 degrees amines), which has been established for more than 100 years and well documented in textbooks, is not possible without conducting complicated organic reactions. We report for the first time unique chemosensors that are capable of showing selective color changes toward 1 degrees -3 degrees amines as a color version of the Hinsberg test. This simple and straightforward qualitative analysis, using the synthesized novel compounds herein, can be considered a new innovative tool for discriminating 1 degrees -3 degrees amines as an alternative to the historical Hinsberg test. 相似文献
107.
We observed, for the first time, the vibronic emission spectrum of the jet-cooled mesityl radical that was formed from mesitylene seeded in a large amount of inert carrier gas helium using a pinhole-type glass nozzle in a corona excited supersonic expansion. The well-resolved vibronic emission spectrum was recorded in the visible region with a long path monochromator. The spectrum was analyzed to identify the origin of the D(2) --> D(0) and D(1) --> D(0) transitions as well as the frequencies of the vibrational modes in the ground electronic state of the mesityl radical by comparison with those of the known data of the precursor and an ab initio calculation. 相似文献
108.
Kee?Sung?LeeEmail author Shiwoo?Lee Ji?Haeng?Yu Doo?Won?Seo Sang?Kuk?Woo 《Journal of Solid State Electrochemistry》2007,11(9):1295-1301
Improvement of long-term stability of 40vol.%NiO–60vol.% yttria-stabilized zirconia (YSZ) anode material in reducing atmosphere
and under exposure to thermal shock through the modification of vacancy concentration and pore shape has been investigated
for a solid oxide fuel cell. We varied the amount of Y2O3 additives from 8 to 10 mol% in YSZ and the type of carbon pore former, from plated activated carbon to spherical carbon black,
to improve the strength and the stability of porous NiO–YSZ anode materials. Modifications by varying the amount of Y2O3 additives and carbon pore former result in a highly stable anode, even upon exposure to a reducing atmosphere for 1,200 h.
In particular, the strengths of the new anode materials are markedly improved at the same porosity level. Higher strengths
do not degrade during a longtime durability test in a reducing atmosphere or upon thermal shock testing. The relatively smaller
degradation of electrical conductivity of the new anode material is discussed in terms of the possibility of suppression of
the disconnectivity of Ni phases during operation of a solid oxide fuel cell. 相似文献
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Kuk Young Cho Chang-Hyeon Kim Jong-Woo Lee Jung-Ki Park 《Macromolecular rapid communications》1999,20(11):598-601
Poly(ethylene glycol) grafted poly(L -lactide) was prepared by ring opening polymerization of L -lactide and epoxy-terminated poly(ethylene glycol) methyl ether (PEGME). Stannous octoate and Al(Et)3·0.5 H2O were tested as polymerization catalysts, and Al(Et)3·0.5 H2O was found to be more effective for the ring-opening of the epoxy group of the modified PEGME monomer. The synthesized polymers were characterized by NMR and the efficiency of the incorporation of epoxy-terminated PEGME in the copolymer was determined. 相似文献