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51.
Silver in solution is determined in situ by the frequency change of a piezoelectric quartz crystal on electrodeposition on the electrode of the crystal. The electrolyte solution flows through a cell containing the platinum-plated electrode (cathode) of the quartz crystal, a coiled platinum-wire anode and a silver—silver(I) chloride reference electrode, and is electrolyzed at —0.2 V vs. . The frequency change is proportional to the silver concentration in the range 10-5–5 × 10-7 M after electrodeposition for 5 min, and in the range 10-8–10-9 M by recycling 20 ml of the solution over the electrodes for 3 h. 相似文献
52.
Akon Higuchi Masatomo Abe Jiro Komiyama Toshiro Iijima 《Journal of membrane science》1984,21(2):113-121
Permeabilities and diffusion coefficients of various gases, Ar, N2, O2, CO2, CH4, C2H4, C3H8 and C4H10, were measured for Water-swollen gel cellophane membranes. No dependence of permeabilities on gas pressure below 1 atm was found. It was observed that the permeability coefficients were not related linearly to the coefficients in bulk water. For the two states of water in the membrane, an analytical method is presented to estimate the diffusion coefficients and the solubilities in free water and non-freezing water. It was found that the diffusion coefficients in non-freezing water were lower than those in free water, and the solubilities in non-freezing water were higher than in free water for all gases studied except CO2 and C2H4, which gave reverse results. 相似文献
53.
Y Murofushi M Kimura H Kuwano Y Iijima M Yamazaki M Kaneko 《Chemical & pharmaceutical bulletin》1988,36(10):3760-3769
54.
Arsenic has been applied to many electronic devices such as electrophotoreceptors, gallium arsenide (GaAs) semiconductors and solid-state image pickup devices. For electrophotoreceptors selenium–arsenic (Se? As) alloys are coated onto the conductive substrate of the receptors. Arsenic is mostly used in electophotoreceptors in electronic devices. During the coating process, a part of the gaseous arsenic is released through an exhaust system. In order to avoid arsenic being discharged to the atmosphere, bag filters and high-efficiency particulate air filters are set before the exhaust port. Any arsenic which still exists in the waste water after washing tools and jigs from the coating process is collected by sedimentation before discharging. The Ames salmonella/microsome plate test for As2Se3 indicated no mutagenic activity under the test system used. For the safety of workers engaged in arsenic-related jobs, they received a medical examination once every six months. No negative trends from the examination was found in 428 men who received the examination from Autumn 1980 to Spring 1987. 相似文献
55.
56.
Treatment of readily available 3-formylquinoline-2-thiol ( 1 ) with ammoniacal sodium hypochlorite directly afforded isothiazolo[5,4-b]quinoline ( 3 ) in high yield, probably via 3-formylquinoline-2-sulfenamide ( 2 ). Facile conversion of 3 to the corresponding 3-amino derivative ( 7 ) was accomplished by the following sequence: base induced opening of the isothiazole ring to 3-cyanoquinoline-2-thiol ( 5 ), oxidation of 5 to the corresponding stable sulfenamide ( 6 ) and sodium ethoxide catalysed reclosure of the isothiazole ring which provided 3-aminoisothiazolo[5,4-b]quinoline ( 7 ). 相似文献
57.
Gabyshev N Abe K Abe K Adachi I Aihara H Asano Y Aulchenko V Aushev T Bakich AM Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fratina S Gershon T Gokhroo G Golob B Gorisek A Hara T Hayashii H Hazumi M Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Imoto A Inami K Ishikawa A Itoh R Iwasaki M Iwasaki Y Kang JH Kang JS Kataoka SU 《Physical review letters》2006,97(24):242001
Using a sample of 152 x 10(6) BB pairs accumulated with the Belle detector at the KEKB e+e- collider, we study the decay mechanism of three-body charmed decay B- --> Lambdac+ ppi-. The intermediate two-body decay B--->Sigmac (2455)0 p is observed for the first time with a branching fraction of (3.7 +/- 0.7 +/- 0.4 +/- 1.0) x 10(-5) and a statistical significance of 8.4sigma. We also observe a low-mass enhancement in the (Lambdac+p) system, which can be parametrized as a Breit-Wigner function with a mass of (3.35(-0.02)(+0.01) +/-0.02) GeV/c2 and a width of (0.07(-0.03)(+0.04) +/-0.04) GeV/c2. We measure its branching fraction to be (3.9(-0.7)(+0.8) +/- 0.4 +/- 1.0) x 10(-5) with a statistical significance of 6.2sigma. The errors are statistical, systematic, and that of the Lambdac+-->pK- pi+ decay branching fraction. 相似文献
58.
Zhang M Yudasaka M Miyauchi Y Maruyama S Iijima S 《The journal of physical chemistry. B》2006,110(18):8935-8940
Through fluorescence-spectrum measurements, we investigated the effects of light-assisted oxidation with H2O2 (LAOx) on single-wall carbon nanotubes (SWNTs) that were individually dispersed in an aqueous solution of surfactant. The intensities of the fluorescence spectra were decreased remarkably by the LAOx when the light's wavelength was 400-500 nm and a little when 600-700 nm. The spectrum intensity did not recover even when the pH was restored to an original value of 6.5. The spectra changed little when the LAOx wavelength was 500-600 nm or the light was not irradiated. In addition, the effect of LAOx on SWNTs was related to the diameters of SWNTs. We inferred that these phenomena reflected that H2O2 was dissociated by absorbing the fluorescence light emitted from optically excited SWNTs, which, in turn, accelerated the burning out of SWNTs. 相似文献
59.
60.
Nishimura K Browder TE Adachi I Aihara H Arinstein K Aushev T Bakich AM Balagura V Barberio E Belous K Bhardwaj V Bischofberger M Bondar A Bozek A Bračko M Chang MC Chao Y Chen A Chen KF Chen P Cheon BG Chiang CC Cho IS Choi Y Dalseno J Danilov M Doležal Z Drutskoy A Eidelman S Gabyshev N Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hyun HJ Iijima T Inami K Itoh R Iwabuchi M Iwasaki Y Joshi NJ Julius T Kang JH Kapusta P Kawai H Kawasaki T Kichimi H Kiesling C Kim HJ 《Physical review letters》2010,105(19):191803
We report a first measurement of inclusive B→Xsη decays, where Xs is a charmless state with unit strangeness. The measurement is based on a pseudoinclusive reconstruction technique and uses a sample of 657×10(6)BB pairs accumulated with the Belle detector at the KEKB e+e- collider. For MXs < 2.6 GeV/c2, we measure a branching fraction of [26.1±3.0(stat)-2.1+1.9(syst)-7.1+4.0(model)]×10(-5) and a direct CP asymmetry of ACP=-0.13±0.04-0.03+0.02. Over half of the signal occurs in the range MXs > 1.8 GeV/c2. 相似文献