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31.
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
32.
The racemic structure of (1RS,3RS)-1,2,3,4-tetrahydro-6,7-dihydroxy-1-methyl-3-isoquinolinecarboxylic acid [(1RS,3RS)-1] was examined based on the melting point, solubility, and IR spectrum, with the aim of optical resolution by preferential crystallization. (1RS,3RS)-1 was indicated from these results to exist as a conglomerate. The successive optical resolution by preferential crystallization of (1RS,3RS)-1 yielded (1S,3S)- and (1R,3R)-1 with optical purities of 85--95% at 66--81% degrees of resolution, which were fully purified by recrystallization. 相似文献
33.
Muliadi Ramli Nasrullah Idris Kenichi Fukumoto Hideaki Niki Fujio Sakan Tadashi Maruyama Koo Hendrik Kurniawan Tjung Jie Lie Kiichiro Kagawa 《Spectrochimica Acta Part B: Atomic Spectroscopy》2007,62(12):1379-1389
A TEA CO2 laser (350 mJ–1.5 J, 10.6 μm, 200 ns, 10 Hz) was focused onto a metal sub-target under He as host gas at 1 atmospheric pressure with a small amount of impurity gas, such as water and ethanol vapors. It was found that the TEA CO2 laser with the help of the metal sub-target is favorable for generating a strong, large volume helium gas breakdown plasma at 1 atmospheric pressure, in which the helium metastable-excited state was then produced overwhelmingly. While the metal sub-target itself was never ablated. The helium metastable-excited state produced after the strong helium gas breakdown plasma was considered to play an important role in exciting the atoms. This was confirmed by the specific characteristics of the detected H emission, namely the strong intensity with low background, narrow spectral width, and the long lifetime. This technique can be used for gas and solid samples analysis. For nonmetal solid analysis, a metal mesh was introduced in front of the nonmetal sample surface to help initiation of the helium gas breakdown plasma. For metal sample, analysis can be carried out by combining the TEA CO2 laser and an Nd–YAG laser where the Nd–YAG laser is used to ablate the metal sample. The ablated atoms from the metal sample are then sent into the region of helium gas breakdown plasma induced by the TEA CO2 laser to be excited through the helium metastable-excited state. This technique can be extended to the analysis of other elements, not limited only to hydrogen, such as halogens. 相似文献
34.
Toyohide Takeuchi Mototada Watanabe Tadashi Hamanaka Hiroki Haraguchi Daido Ishii 《Journal of separation science》1990,13(9):606-609
Capillary columns of 0.3-0.5 mm i.d. packed with 3- to 30-μm silica-based stationary phases for liquid chromatography were used for gas chromatographic separation of hydrocarbons. Column efficiencies were evaluated for various commercially available packing material. The best column efficiency was achieved with 5-μm octadecyl group bonded silica gel, the surface of which was coated with a poly (dimethylsiloxane) film. The 30-cm column produced 11,000 theoretical plates. 相似文献
35.
The percutaneous absorption of ketoprofen (KPF) from gel patches containing d-limonene and ethanol was investigated in rats. Plasma levels of KPF varied with the kind of polymers which constitute the gel patch, and the highest level was observed when the copolymer of ethylacrylate (EA) and diethyleneglycolmethacrylate (DEGMA) was used as a vehicle. The amount of KPF permeating through the rat skin from the gel patch was well correlated with that of ethanol. Permeations were enhanced with increase in the amount of d-limonene distributed from the vehicle to the skin tissue. The amount of d-limonene accumulated in the skin varied greatly with the kind of polymers; the highest accumulation was observed with the EA-DEGMA copolymer, and decreased with increasing affinity of d-limonene to the polymers. The reason EA-DEGMA copolymer showed the highest percutaneous absorption of KPF from gel patches containing d-limonene may be the hydrophilic nature of this polymer which showed the lowest affinity to d-limonene. 相似文献
36.
Hiizu Iwamura Tadashi Sugawara Yuzo Kawada Kazuo Tori Ryonosuke Muneyuki Ryoji Noyori 《Tetrahedron letters》1979,20(36):3449-3452
Natural-abundance 17O NMR spectra have been measured for twenty one oxiranes. Their chemical shifts covering a 100 ppm range were interpreted in terms of the paramagnetic β- and diamagnetic γ-effects. In addition, through-space orbital interaction between the ethylenic π and the Walsh orbitals of the oxirane ring was suggested by a lowfield shift in norbornadiene -oxide. 相似文献
37.
Matsuo G Kawamura K Hori N Matsukura H Nakata T 《Journal of the American Chemical Society》2004,126(44):14374-14376
Brevetoxin-B (BTX-B), produced by the red tide organism, Gymnodium breve Davis, is the first member of marine polycyclic ethers to be structurally elucidated and one of the most potent neurotoxins. The structural feature is a trans-fused polycyclic ether ring system with 23 stereocenters. Its unique, complex structure and potent biological activity have attracted the attention of synthetic organic chemists. Total synthesis of BTX-B has been accomplished via the coupling of the ABCDEFG and IJK-ring segments, each ether ring of which was stereoselectively and efficiently constructed on the basis of SmI2-induced intramolecular cyclization, 6-endo-cyclization of hydroxy epoxide, ring-closing olefin metathesis, and SmI2-induced intramolecular Reformatsky-type reaction. Several kinds of double reactions at the left and right sides were efficiently used through the synthesis. 相似文献
38.
Tadashi Kawai Masako Komaki Tomokazu Iyoda 《Journal of molecular catalysis. A, Chemical》2002,190(1-2):45-53
Metathesis of 2-vinyl aromatic heterocycles such as furan, thiophene, pyrrole and pyridine in the presence of a molybdenum-based Schrock catalyst has been investigated from a synthetic point of view. The self-metathesis of 2-vinyl aromatic heterocycles was not successful. However, in cross-metathesis of thiophene, furan and styrene with 1-octene, the cross-metathesis product, heterodimer, was readily obtained selectively, together with only small amounts of the two corresponding self-metathesis products. The origin of the surprisingly high selectivity of heterodimer formation was elucidated through metallacyclobutane intermediate mechanism, observations of carbenes by in situ 1H NMR, and reaction products. 相似文献
39.
Kawasaki H Sasaki A Kawashima T Sasaki S Kakehashi R Yamashita I Fukada K Kato T Maeda H 《Langmuir : the ACS journal of surfaces and colloids》2005,21(13):5731-5737
Lyotropic phase behavior of the nonionic and the half-ionized oleyldimethylamine oxide (OlDMAO)/water systems was investigated using polarized light microscopy, small-angle X-ray diffraction, and differential scanning calorimetry. Nonionic OlDMAO formed isotropic micellar solution, nematic, hexagonal, cubic, and lamellar liquid crystalline phases as the surfactant concentration increased. In contrast, half-ionized OlDMAO (i.e., 1:1 mixture of the nonionic and the protonated species) had a greater tendency to form bilayer structures, and the phase diagram became quite similar to those of double-chained ionic surfactants rather than single-chained ones, despite the introduction of positive charges to the nonionic one. The preference of the bilayer structures in the half-ionized OlDMAO was interpreted in terms of the dimers stabilized by the hydrogen bond between the nonionic and protonated species. For alkyldimethylamine oxides with a saturated hydrocarbon chain (CnDMAO, chain length: n = 14, 16, and 18), the phase sequence of lyotropic liquid crystals was hardly affected by the protonation, but an elongation of the cylinders of the hexagonal phase was observed for the half-ionized C14DMAO. Consequently, it can be considered that the dominant bilayer formation of the half-ionized OlDMAO is attributed to the combined effect of the hydrogen-bonded dimer formation and the cis-double-bond configuration of the alkyl chain. 相似文献
40.
Enzyme heterobilayer-modified electrodes were fabricated by successively covalently binding to the surface of a tin(IV) oxide plate horseradish peroxidase (HRP), then an oxidase (lactate, pyruvate or cholesterol oxidase or uricase), which liberates hydrogen peroxide by reaction with the respective substrate. The cooperative action of oxidase-HRP leads to an efficient amperometric sensor system with the minimum amount of enzyme immobilized on an electrode. 相似文献