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81.
A 1-l water sample was concentrated to 20ml by freezing and analyzed for soluble, colloidal and insoluble silica by the spectrophotometric heteropoly blue method and by inductively coupled plasma/atomic emission spectrometry. High-purity water obtained from a vitreous-silica sub-boiling distillation still contained a few micrograms of insoluble silica per liter. 相似文献
82.
Yoshinori Tominaga Lyle W. Castle Raymond N. Castle 《Journal of heterocyclic chemistry》1993,30(3):845-847
6-Aminobenzo[b]naphtho[2,1-d]thiophene has been prepared by two different routes, one, a one-pot synthesis. 相似文献
83.
Yoshinori Asakawa Tsunematsu Takemoto Masao Toyota Takaaki Aratani 《Tetrahedron letters》1977,18(16):1407-1410
The stereostructures of the two new exceptional diterpene dialdehydes from the liverwort, Trichocoleopsis sacculata: sacculatal (1), responsible for the characteristic pungent taste, and isosacculatal (2) have been determined by the spectral evidence and by comparison with polygodial (3), isopolygodial (4), and drimanediol (6) of known relative configurations. 相似文献
84.
Atsuko Kawata Tadashi Oishi Yoshitaka Fukada Yoshinori Shichida Tôru Yoshizawa 《Photochemistry and photobiology》1992,56(6):1157-1166
Types of photoreceptor cells in the retinas of 36 species of vertebrates (5 classes, 14 orders) were investigated immunocytochemically with monoclonal antibodies against chicken iodopsin (Io-mAb) and antiserum against bovine rhodopsin (Rh-As). In mammals, Rh-As labeled the outer segments of some photoreceptor cells in striped squirrels (a diurnal mammal) and those of most photoreceptor cells in mice (a nocturnal mammal), while Io-mAb labeled any photoreceptor cells in either of them. In all species of birds studied, Io-mAb labeled the principal and accessory members of double cones and single cones with a red oil droplet. Rh-As labeled single cones with a yellow or clear oil droplet in addition to rods. In turtles, both Rh-As and Io-mAb labeled single cones with a red or clear oil droplet and the principal (with a yellow oil droplet) and accessory members of double cones. This suggests that the visual pigments in these cones of turtles have common epitopes with bovine rhodopsin and chicken iodopsin. In Japanese grass lizards, single cones with a yellow oil droplet and double cones were immunoreactive to both Rh-As and Io-mAb. In snakes, rods and cones could not be distinguished but both positively and negatively stained cells were observed by the use of each antibody. In geckos, however, all photoreceptor cells were immunonegative to Io-mAb. In all species studied in amphibians, Rh-As labeled rods but not cones. Neither rods nor cones reacted with Io-mAb. In fishes, almost all species studied had well developed cones, and some of these cones were labeled by Rh-As. However, Io-mAb labeled the outer segments of some cones only in loaches. Rh-As labeled photoreceptor cells in all species of fishes studied. Thus, Rh-As recognized the outer segments of rods in all species studied from fishes to mammals, whereas the epitope recognized by Io-mAb is conserved in some species of fishes, most species of reptiles and all species of birds studied. 相似文献
85.
Yoshinori Fujimoto Miki Kimura Akihiro Takasu Fathy A.M. Khalifa Masuo Morisaki Nobuo Ikekawa 《Tetrahedron letters》1984,25(14):1501-1504
Deuterated stigmasterols (10, 11 and 12) were chemically synthesized and fed to silk-worm larvae. GC-MS analysis of the metabolites, cholesterol (4) and desmosterol (6), indicates the migration of 25-hydrogen to C-24 position during stigmasterol dealkylation. 22,24(28)-Dienes(8a and 8b) were shown to be converted to 22,24-diene (5), desmosterol and cholesterol. 相似文献
86.
Regio- and diastereoselective reaction of oxygen and sulfur substituted allylic carbanions with aldehydes is described. Either threo or erythro isomer can be obtained predominantly or exclusively by merely choosing an additive. 相似文献
87.
Yoshiaki Hamada Kazuko Hashiguchi Masamichi Tsuboi Yoshinori Koga Shigeo Kondo 《Journal of Molecular Spectroscopy》1984,105(1):70-80
Methyleneimine was detected in the gas phase by a moderately high resolution infrared spectrometer as one of the intermediate species produced by a pyrolysis of amines. Observed vibrational frequencies of some isotopic derivatives have been combined with the ab initio values to reach a most reliable force constants set. Some other spectroscopic parameters, involving geometrical parameters and dipole moment derivatives, have also been calculated ab initio and compared with the observation. Its half-life in our experimental apparatus was about 10 min, which is much longer than the previously reported values, 0.1 or 10 sec. 相似文献
88.
89.
90.
Copper-mediated chemoselective trifluoromethylation at the benzylic position by the use of shelf-stable electrophilic trifluoromethylating reagents 3 in good to high yields under mild conditions is described for the first time. The generality of this trifluoromethylation for a wide variety of benzyl bromides facilitates the rapid creation of structural diversity of medicinal candidates in drug discovery. 相似文献