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11.
Hideki Namba Okihiro Tokunaga Tadashi Tanaka Yoshimi Ogura Shinji Aoki Ryoji Suzuki 《Radiation Physics and Chemistry》1993,42(4-6):669-672
The fundamental research work with simulated coal-fired flue gas was performed in JAERI to get basic data for electron beam treatment of flue gas from thermal power plants in Japan. The standard condition of the experiments was set to be the same as that of next large scale pilot test in Nagoya. The concentrations of NOx and SOx were 225 ppm and 800 ppm, respectively. The temperature of the system was 65°C. The effect of multiple irradiation was observed for NOx removal. The target SOx and NOx removals (94% and 80%, respectively) with low NH3 leakage (less than 10 ppm) were achieved at 9 kGy irradiation with 0.9 NH3 stoichiometry during 7 hours continuous operation. The facility for the pilot plant (12,000 Nm3/hr) has just built at the site of Shin-Nagoya power plant of Chubu Electric Power Company and will be started in full operation in November 1992. 相似文献
12.
Hiroshi Nishikawa Ei-Ichi Terada Eishun Tsuchida Yoshimi Kurimura 《Journal of polymer science. Part A, Polymer chemistry》1978,16(10):2453-2463
The (alkyl)-bis(dimethylglyoximato)pyridinecobalt attached to polychloromethylstyrene by a cobalt–carbon bond was prepared by the reaction of Co(II)(DH)2Py with polychloromethylstyrene in benzene. The fraction of p-vinylbenzyl·Co(DH)2Py introduced to the polymer was 8.1 and 2.1 mole %. The photodecomposition of the polymer-bonded cobaloxime was investigated by following the change of the visible spectrum. The rate constant kdec of the polymer-bonded cobaloxime was 1.1 × 10?2 sec?1 in benzene; it is one-fourth of that of its monomeric analog, benzyl·Co(DH)2Py. The kdec values of the cobaloximes were also measured in benzene–dimethyl sulfoxide mixed solvents, and the polymer effects were discussed. The dependence of the photodecomposition on energy of the irradiation light was investigated, and it was found that the absorption band near 470 nm is important for the photodecomposition of the cobalt–carbon bond. Spectroscopic measurements of the ligand exchange reaction of polymer-bonded cobaloxime with pyridine in dimethyl sulfoxide gave a larger equilibrium constant (1.2 × 104 liter/mole) than that of benzyl·Co(DH)2Py (9.4 × 102 liter/mole). The kinetic data of the ligand exchange reaction indicated that the larger equilibrium constant for the polymeric system is due to the smaller rate constant of the reverse reaction. The thermodynamic parameters were also obtained. 相似文献
13.
14.
Natural graphite samples with average particle sizes of 5, 10 and 15 μm (NG5 μm, NG10 μm and NG15 μm, respectively) were fluorinated by ClF3 (3 × 104 Pa) at 200 and 300 °C for 2 min. X-ray photoelectron spectra of surface-fluorinated samples showed that surface fluorine concentration increased with increase in the particle size of graphite and reaction temperature. Small amounts of chlorine were also detected in all the fluorinated samples. Raman spectra of original and surface-fluorinated samples indicated that the surface disordering was increased for NG10 μm and NG15 μm. Surface areas were decreased by the fluorination for NG5 μm and NG10 μm but unchanged for NG15 μm. The mesopores with diameter of 1.5-2 nm increased while those of 2-3 nm decreased for all the samples. First coulombic efficiencies for NG10 μm and NG15 μm were highly increased by surface fluorination in 1 mol/dm3 LiClO4-EC/DEC/PC (EC: ethylene carbonate, DEC: diethyl carbonate, PC: propylene carbonate) solution. 相似文献
15.
The pressure effect on the decay rate of chemically induced dynamic electron spin polarization (CIDEP) was investigated on several free-radical intermediates in photolysis, and the spin-lattice relaxation times for these radicals were estimated from the decay rates of CIDEP signals at various pressures. The spin-lattice relaxation rates were retarded by increasing external pressure. From the pressure dependence of the spin-lattice relaxation rates the activation volume was estimated. The activation volumes of these radicals divide into two groups; ≈30 cm3 mol−1 for negative ions and ≈10 cm3 mol−1 for neutral radicals. 相似文献
16.
17.
A chiral amino alcohol/Ir complex catalyzes the asymmetric oxidative lactonizations of meso-diols to give the corresponding lactones in up to 81% ee. 相似文献
18.
Konoike T Matsumura K Yorifuji T Shinomoto S Ide Y Ohya T 《The Journal of organic chemistry》2002,67(22):7741-7749
A practical multikilogram-scale synthesis of enantiomerically pure S-1255 (1), a potent and orally active ET(A) receptor antagonist, is described. Utilizing readily available starting materials and reagents, the entire sequence of reactions starting from 2,5-dihydroxyacetophenone 8 proceeded under mild conditions to give 1 in an excellent chemical yield (8 steps, 41% overall yield) and in a high enantiopurity (98% ee). The crucial step of the synthesis is a dynamic resolution of key intermediate 16. (R)-Methoxy acid (R)-16 having 97-99% ee was obtained in 83-84% yield from racemic 16 as a crystalline (1S,2R)-(+)-norephedrine or (+)-cinchonine salt by the dynamic resolution comprising concurrent crystallization and in situ racemization. A mechanism of the dynamic resolution through a ring-opened zwitterionic intermediate is discussed. In the final synthetic step, an effective carbon-carbon bond formation between the C4 carbon and the p-anisyl group was accomplished by a conjugate addition-elimination reaction of Grignard reagent 3 to (R)-16 to give 1 having 98% ee. Owing to high efficiencies of functional group transformations, carbon-carbon bond formations, and the dynamic resolution, the synthesis required no chromatographic purification and was amenable to a multikilogram-scale preparation. Several kilograms of 1 for clinical trials were successfully prepared by this process. 相似文献
19.
Nishizawa M Kohno M Nishimura M Kitagawa A Niwano Y 《Chemical & pharmaceutical bulletin》2005,53(7):796-799
Using a new method having been developed for the purpose of quantitative determination for peroxyradicals, the presence of peroxyradicals was proved in cigarette smoke. In brief, peroxyradicals in cigarette smoke were measured by ESR spectrometry coupled to non-reductive scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH). As a result, peroxyradicals were found to be major reactive oxygen species (ROS) since the concentration of peroxyradicals recovered from cigarette smoke was much higher than that of any of other ROS (superoxide and hydroxyl radical) and nitric oxide. Furthermore, several antioxidants (ascorbic acid, reduced glutathione, epigallocatechin gallate, shikonin) were examined for scavenging activity against peroxyradicals in the cigarette smoke. Among them shikonin alone exerted the scavenging activity, suggesting that shikonin is promising antioxidant for cigarette filters because of its effectiveness against broad range of ROS including peroxyradicals, heat resistance, nonvolatility and high affinity to the filter. 相似文献
20.
Shimizu K Suzuki H Hayashi E Kodama T Tsuchiya Y Hagiwara H Kitayama Y 《Chemical communications (Cambridge, England)》2002,(10):1068-1069
Direct 1,4-conjugate addition of naked aldehydes to vinylketones is catalysed effectively by N-methyl-3-aminopropylated FSM-16 mesoporous silica, which can be regarded as a novel heterogeneous catalysis for a practical C-C bond formation reaction. 相似文献