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41.
A fluorescein–spiropyran conjugate (2) behaves as a receptor for colorimetric sensing of cyanide anion (CN?) in aqueous media under irradiation of UV light. The compound 2, which exists as a spirocycle-closed (SP) form in the dark condition, is isomerized to the spirocycle-opened merocyanine (MC) form upon irradiation of UV light and shows absorption bands at 467 and 568 nm. Addition of CN? to the solution leads to a decrease in these bands and an appearance of new absorption band at 512 nm, via a nucleophilic interaction between CN? and the spirocarbon of MC form. This absorption change occurs selectively with CN? and enables ratiometric quantification of CN? by absorption analysis. 相似文献
42.
The behavior of heavy solutes present in a sample injected on the precolumn has not been clarified in on-column injection onto gas chromatograph having a capillary column coupled to an uncoated precolumn in an oven. To investigate this point, an on-column gas chromatograph has been developed which is constructed with a heatable precolumn outside the oven. Some experiments were carried out in order to evaluate the performance. As a result, it was found that heavy solutes reach the first part of the main capillary column after the solvent has gone, resulting in sharp peaks without solvent effects. The reason why sharp peaks appear for the heavy solutes is also discussed. The cold-trapping effect has been shown to play an important role in narrowing the band width of the heavy solutes. Some of the advantages of the gas chromatograph developed are also presented. 相似文献
43.
44.
Simultaneous electrodeposition of actinides 总被引:1,自引:0,他引:1
Shu-Tian Liu Ying Ban Shuichi Sumiya Junichiro Ishida Makoto Iwai 《Journal of Radioanalytical and Nuclear Chemistry》1988,121(1):167-174
A new system for simultaneous electrodeposition of U, Np, Pu, Am and Cm has been developed. The system consists of (NH4)2C2O4–H2SO4–HCl. The effects on recovery of pH, current density, interfering ions and the amount of added HCl have been studied. The optimum condition for simultaneous electrodeposition of actinides has been recommended. Under the recommended condition recoveries of U, Np, Pu, Am and Cm have been obtained by using232U,237Np,241Am,242Pu and244Cm. The counting sources prepared are uniform, adherent and suitable for -spectrometry. 相似文献
45.
46.
Kubo Y Grezes C Dewes A Umeda T Isoya J Sumiya H Morishita N Abe H Onoda S Ohshima T Jacques V Dréau A Roch JF Diniz I Auffeves A Vion D Esteve D Bertet P 《Physical review letters》2011,107(22):220501
We report the experimental realization of a hybrid quantum circuit combining a superconducting qubit and an ensemble of electronic spins. The qubit, of the transmon type, is coherently coupled to the spin ensemble consisting of nitrogen-vacancy centers in a diamond crystal via a frequency-tunable superconducting resonator acting as a quantum bus. Using this circuit, we prepare a superposition of the qubit states that we store into collective excitations of the spin ensemble and retrieve back into the qubit later on. These results constitute a proof of concept of spin-ensemble based quantum memory for superconducting qubits. 相似文献
47.
Takeshi Shimomura Touru Sumiya Masatoshi Ono Tetsuji Ito Taka-aki Hanaoka 《Analytical and bioanalytical chemistry》2013,405(1):297-305
A disposable amperometric biosensor for ketone 3-β-hydroxybutyrate (3HB) has been developed successfully. The sensor is based on a screen-printed carbon electrode containing Meldola’s Blue (MB) and sensing components containing nicotinamide adenine dinucleotide (NAD+) and 3-β-hydroxybutyrate dehydrogenase (3HBDH) immobilized in mesoporous silica (FSM8.0) using an aqueous photo-cross-linkable polymer matrix of polyvinyl alcohol (O-391), and it requires only a small sample volume of 10 μL for the measurement. The behavior of a resulting biosensor, i.e., 3HBDH–FSM8.0/NAD+/MB-SPCE, was examined in terms of NAD+ concentration for construction, pH, applied potential, operational range, selectivity, and storage stability. The sensor showed an optimum response at a pH of 7.6 and at an applied potential of ?50 mV. The determination range and the response time for 3HB were from 30 μM to 8 mM and approximately 30 s, respectively. In addition, the sensor was quite stable and maintained >90 % of its initial response after being stored for over 6 months. This result implies that our method provides a novel biosensor for ketone 3-β-hydroxybutyrate which is easy-to-use, cost-effective, and has good reproducibility, which are vital for commercial purposes. Figure
Layer structure and operation mechanism of 3HB biosensor 相似文献
48.
Giseop Kwak Ken-Ichi Sumiya Fumio Sanda Toshio Masuda 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3615-3624
Polymerization of p-(dimethylsilyl)phenylacetylene in toluene at 25 and 80 °C with RhI(PPh3)3 catalyst afforded highly regio- and stereoregular poly(dimethylsilylene-1,4-phenylenevinylene)s [cis- and trans-poly( 1a )s] containing 98% cis- and 99% trans-vinylene moieties, respectively. The trans-type polymers exhibited redshifts and hyperchromic effects in the ultraviolet–visible spectrum as compared with the cis-type counterparts. Photoirradiation of cis- and trans-poly( 1a )s gave cis-rich mixtures at equilibrium states. The trans and cis polymers exhibited different emission properties, for example—trans polymer, emissn λmax = 400 nm, quantum yield: 3.4 × 10−3 and cis polymer, emissn λmax = 380 nm, quantum yield: 1.5 × 10−3. Besides poly( 1a ), poly(dimethylsilylenearylenevinylene)s containing biphenylene and phenylenesilylenephenylene units [poly( 3 )] were prepared. The extent of conjugation in these polymers decreased in the orders of biphenylene > phenylene > phenylenesilylenephenylene as well as trans-vinylene > cis-vinylene. The quantum yield of the trans-rich polymer with biphenylene moiety was fairly large and 0.15. Polyaddition of 1,4-bis(dimethylsilyl)benzene and three types of diethynylarenes (4,4′-diethynylbiphenyl, 2,7-diethynylfluorene, and 2,6-diethynylnaphthalene) catalyzed by RhI(PPh3)3 provided novel regio- and stereoregular polymers [poly( 6 )]. These polymers displayed blue light emission with high quantum yields (4–81%). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3615–3624, 2003 相似文献
49.
K. Tamura T. Makino A. TsukazakiM. Sumiya S. FukeT. Furumochi M. Lippmaa C.H. Chia Y. Segawa H. Koinuma M. Kawasaki 《Solid State Communications》2003,127(4):265-269
We have grown nitrogen-doped ZnO (ZnO:N) films by laser molecular-beam epitaxy. The use of lattice-matched ScAlMgO4 substrates prevented the degradation of crystallinity induced by the nitrogen incorporation to the films. Despite this improvement, we have not obtained ZnO:N films which showed p-type conductivity. We studied the optical properties of these ZnO:N films. Donor-acceptor pair (DAP) luminescence was observed. The results indicate the formation of an acceptor state. The energy position of the DAP luminescence is lower than that reported by Look et al. [Appl. Phys. Lett. 81 (2002) 1830]. The DAP luminescence band shifts to lower energy with increasing nitrogen concentration. A photoluminescence recombination possibly due to the free-electron-to-acceptor (FA) transition was observed at temperatures higher than 40 K. The acceptor ionization energy was estimated from the energy position of the FA luminescence to be 266 meV. 相似文献
50.
Hayashi Y Yamaguchi J Sumiya T Hibino K Shoji M 《The Journal of organic chemistry》2004,69(18):5966-5973
The direct proline-catalyzed asymmetric alpha-aminoxylation of aldehydes and ketones has been developed using nitrosobenzene as an oxygen source, affording alpha-anilinoxy-aldehydes and -ketones with excellent enantioselectivity. Reaction conditions have been optimized, and low temperature (-20 degrees C) was found to be a key for the successful alpha-aminoxylation of aldehydes, while slow addition of nitrosobenzene is essential for that of ketones. The scope of the reaction is presented. 相似文献