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151.
Y. Hashimoto L. Matsuoka D. NagamotoS. Hasegawa 《Spectrochimica Acta Part B: Atomic Spectroscopy》2008
We developed an ion trap — laser cooling system for observing the laser induced fluorescence (LIF) of a single ion, in the view of utilizing it for the trace isotope analysis of Ca. We observed stepwise LIF signals, which correspond to the numbers of trapped 40Ca+ ions (40Ca/Ca = 96.9%). The detection efficiency was evaluated and the observation of single ions demonstrated the experimental feasibility of trace isotope analysis. Furthermore, as the next step towards trace isotope analysis, we report observation of the even calcium isotopes, 44Ca (44Ca/Ca = 2.09%) and 48Ca (48Ca/Ca = 0.187%), without the use of a selective loading method. 相似文献
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Tamio Kamidate Yasunori Hashimoto Hirofumi Tani Akihiko Ishida 《Analytical sciences》2002,18(3):273-276
The uptake of Cu2+ was investigated using various types of liposomes composed of phosphatidylcholine (PC), cholesterol (Chol) and dicethylphosphate (DCP). DCP played a role as a ligand for Cu2+. Multilamellar vesicles (MLVs) were more effective for the uptake of Cu2+ compared to unilamellar vesicles prepared by the extrusion technique. The uptake efficiency of MLVs for Cu2+ was dependent on the molar ratio of DCP in MLVs. The uptake percent of Cu2+ was 92% using MLVs having a PC:DCP:Chol molar ratio of 4:3:3; 95% of the total vesicle Cu2+ was bound to DCP of the outer membrane surface of the MLVs, and the remaining 5% of the total Cu2+ was distributed into the interior side of the MLVs. MLVs having a PC:DCP:Chol molar ratio of 4:3:3 were also effective as separation media for Mn2+, Co2+, Ni2+ and Zn2+. The uptake efficiency of the MLVs for the transition-metal ions increased in the order Co2+ < Zn2+ < Ni2+ < Mn2+ < Cu2+. 相似文献
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Langmuir-Blodgett (LB) monolayers of 22-tricosenoic acid deposited on layered tungsten diselenide (WSe2) have been investigated by Scanning Tunneling Microscopy (STM) in air. Reproducible molecular scale imaging of extended areas (16×16 nm) of the films was possible over more than two months after preparation. This indicates a high stability of the films on this type of polar substrates. The two-dimensional lattice of the organic film is incommensurate to the lattice of the WSe2 substrates. The STM experiments also indicate that the tip partially penetrates the organic film without destroying the film structure. 相似文献
158.
Tamotsu Hashimoto Yusuke Makino Michio Urushisaki Toshikazu Sakaguchi 《Journal of polymer science. Part A, Polymer chemistry》2008,46(5):1629-1637
Living cationic polymerization of 2‐adamantyl vinyl ether (2‐vinyloxytricyclo[3.3.1.1]3,7decane; 2‐AdVE) was achieved with the CH3CH(OiBu)OCOCH3/ethylaluminum sesquichloride/ethyl acetate [CH3CH(OiBu)OCOCH3/Et1.5AlCl1.5/CH3COOEt] initiating system in toluene at 0 °C. The number‐average molecular weights (Mn's) of the obtained poly(2‐AdVE)s increased in direct proportion to monomer conversion and produced the polymers with narrow molecular weight distributions (MWDs) (Mw/Mn = ~1.1). When a second monomer feed was added to the almost polymerized reaction mixture, the added monomer was completely consumed and the Mn's of the polymers showed a direct increase against conversion of the added monomer. Block and statistical copolymerization of 2‐AdVE with n‐butyl vinyl ether (CH2?CH? O? CH2 CH2CH2CH3; NBVE) were possible via living process based on the same initiating system to give the corresponding copolymers with narrow MWDs. Grass transition temperature (Tg) and thermal decomposition temperature (Td) of the poly(2‐AdVE) (e.g., Mn = 22,000, Mw/Mn = 1.17) were 178 and 323 °C, respectively. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1629–1637, 2008 相似文献
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Hiroki Hotta Kazuya Tatsuno Yoji Hattori Takuya Hashimoto Masayuki Uehara Kin-ichi Tsunoda 《Electrochemistry communications》2008,10(9):1351-1354
The H+ concentration change was monitored near an electrode surface through an electrolysis using a slab optical waveguide technique. Indium tin oxide transparent electrode modified by porous insulating polymer to which methyl red was covalently immobilized was used as a guiding layer, and the absorbance change of the polymer film was monitored. H+ generation at the vicinity of the electrode through the oxidation of ascorbic acid could be monitored by this technique. 相似文献