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101.
S. Hisamatsu T. Katsumata Y. Takizawa 《Journal of Radioanalytical and Nuclear Chemistry》1992,161(2):455-463
Tritium (3H) concentrations in diet samples from Akita City, northern Japan, and in human tissue samples from the general population of Akita Prefecture were analyzed to study fallout3H transfer.3H concentrations in human soft-tissue samples have been previously found to be similar to those in diet samples. In this study, higher organically-bound3H (OBT) concentrations were found in human costal cartilage and sternum samples than in the soft-tissues. Mean residence times of OBT in the cartilage and sternum were estimated to be 57 years and <6 years, respectively, with a single compartment model which took into account compartment growth. 相似文献
102.
Masataka Mochizuki Takako Anjo Yuko Wakabayashi Toshie Sone Masashi Okada 《Tetrahedron letters》1980,21(18):1761-1764
N-alkyl-N-(1-hydroperoxyalkyl)nitrosamines were prepared by treatment of the corresponding 1-acetoxyalkyl nitrosamines with hydrogen peroxide in acetic acid through an acid-catalyzed nucleophilic substitution. 相似文献
103.
104.
Tricyclic sulfonamides were synthesized by the generation of aziridinyllithiums from N-tosylaziridines followed by an intramolecular nucleophilic reaction and the subsequent reaction with electrophiles using a flow microreactor system. The reactions could be carried out at 0 °C, although much lower temperatures such as ?78 °C are needed for batch macro reactors. 相似文献
105.
Prof. Dr.-Ing. S. Igarashi K. Shibukawa Prof. Dr. rer. nat. É. I. Takizawa 《Archive of Applied Mechanics (Ingenieur Archiv)》1985,55(5):333-341
Summary The equations of deflection of a thick plate presented in a previous paper are solved for an infinite plate under sinusoidally distributed pressure acting at its upper surface.The deflection and stress of the plate are calculated from the solutions of the approximate equations. The results are compared with those calculated from the exact solution and also with those obtained from other approximate methods.
Über die Durchbiegung einer dicken Platte unter einer sinusförmigen Last
Übersicht Die in einer früheren Arbeit gegebenen Gleichungen für die Durchbiegung einer dicken Platte werden für den Fall einer unendlichen Platte gelöst, deren Deckfläche durch einen sinusförmigen verteilten Druck belastet wird.Aus den Lösungen der Näherungsgleichungen werden die Durchbiegung und die Spannung einer dicken Platte berechnet. Die Ergebnisse werden mit dem aus der exakten Lösung erlangten Resultat sowie mit den aus anderen Näherungsverfahren erhaltenen Ergebnissen verglichen.相似文献
106.
Masahiro Inoue Yamato Hayashi Hirotsugu Takizawa Katsuaki Suganuma 《Colloid and polymer science》2010,288(10-11):1061-1069
Nanostructured Ag films composed of nanoparticles and nanorods can be formed by the ultrasonication of ethanol solutions containing Ag2O particles. The present work examined the formation process of these films from ethanol solutions by two different agitation methods, including ultrasonication and mechanical stirring. The mass-transfer process from Ag2O particles to ethanol solvent is accelerated by the mechanical effects of ultrasound. Ag+ ions and intermediately reduced Ag clusters were released into the ethanol. These Ag+ ions and Ag clusters provide absorption bands at 210, 275 and 300 nm in UV-vis spectra. These bands were assigned to the absorption of Ag+, Ag 4 2+ and Agn (n?≈?3). The Agn clusters that readily grow to become Ag nanoparticles were formed due to the surface reaction of Ag2O particles with ethanol under ultrasonication. The reactions of Ag+ ions in ethanol to form Ag nanomaterials (through the formation of Ag 4 2+ clusters) were also accelerated by ultrasonication. 相似文献
107.
108.
Ayumi Takizawa Eriko Doi Akio Murai Hidetoshi Kawai Takanori Suzuki 《Tetrahedron》2006,62(31):7408-7435
Convergent synthesis of the common FGHI-ring part (54) of ciguatoxins was achieved via the following key steps: (i) the Nozaki-Hiyama-Kishi reaction connecting the F-ring part (6) with the I-ring part (7); (ii) regio- and stereoselective epoxidation; (iii) the 6-exo-epoxide opening reaction forming simultaneously the H-ring and the quaternary asymmetric center at C30; (iv) inversion of the C29 stereocenter by a two-step oxidation/reduction process, where the successful inversion depended on proper management of the steric environment of the substrate; and (v) final reductive cyclization constructing the G-ring. 相似文献
109.
The effect of inorganic salts with different charge numbers of cations on the adsorption and micelle formation of dodecylammonium chloride (DAC) was clarified by applying the thermodynamic treatment of surfactant mixtures to mixtures of DAC with calcium and lanthanum chlorides and comparing the results with those of the sodium chloride-DAC mixture in the previous study. Surface tension of aqueous solutions of the salt-DAC mixture was measured as a function of the total molality of the mixture and the mole fraction of DAC in the mixture at 298.15 K under atmospheric pressure. Judging from the phase diagrams of adsorption and micelle formation obtained from the surface tension measurement, dodecylammonium cations expel inorganic cations from the adsorbed film and micelle and the repulsive interaction between dodecylammonium and inorganic cations increases with increasing charge number of the inorganic cation. 相似文献
110.
Thibault RJ Takizawa K Lowenheilm P Helms B Mynar JL Fréchet JM Hawker CJ 《Journal of the American Chemical Society》2006,128(37):12084-12085
Using facile, highly modular synthetic approaches, a new monomer family based on a 1,2,3-triazole-4-vinyl building block has been prepared, and various functional derivatives have been obtained. Subsequent homo- and copolymerization of these novel functionalized monomers gives polymeric materials with unique physical properties, combining many attractive features of more traditional monomers, such as styrene, vinylpyridine, and meth/acrylates. 相似文献