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241.
Y. Yabushita Y. Kanayama T. Tarohda S. Enomoto R. Amano 《Journal of Radioanalytical and Nuclear Chemistry》2003,256(3):481-488
Radioactive multitracer technique was applied to study the screening of in vivo interrelations between radioactive tracers (46Sc, 54Mn, 58Co, 65Zn, 75Se, 83Rb, 85Sr and 88Zr) and stable Zn species. Comparative uptake rates were examined in the blood, nine organs (thymus, lung, cardiac muscle, spleen, pancreas, kidney, liver, testes and bone) and eight brain regions (cerebral cortex, striatum, hippocampus, thalamus and hypothalamus, midbrain, cerebellum, pons and medulla, olfactory bulb) using 3-week-old mice fed by four kinds of Zn-deficient, -adequate and -excessive diets with Zn content from 0.7 to 3520 ppm. As a result, no significant difference between the dietary Zn-deficient state (Zn content: 3.6 ppm) and Zn-adequate state (Zn content: 36 ppm) was observed in the uptake rates of 65Zn and other 46Sc, 54Mn, 58Co and 75Se, except for 83Rb. In addition, significant differences among the organ and brain regional uptakes of 46Sc, 54Mn, 58Co, 75Se and 83Rb were found in the dietary Zn-excessive state (Zn content: 3520 ppm). These results indicate that the organ and brain regional uptakes of tracers in Zn-deficient and excessive mice are strongly correlated with the blood uptakes and retentions of the tracers. Furthermore, the multitracer screening gives us new findings concerning the diet-related element-element interrelations in living bodies. 相似文献
242.
243.
S. Enomoto M. Asahina S. Satoh 《Journal of polymer science. Part A, Polymer chemistry》1966,4(6):1373-1390
Poly(vinyl chloride) (PVC) and all its deuterated derivatives were prepared by variation of the polymerization method and polymerization temperature to study the structure of PVC and the mechanism of addition polymerization by infrared spectroscopy and high resolution NMR spectroscopy. The CH and CH2 stretching modes of PVC were assigned completely from the infrared spectra of PVC-αd1, PVC-β,βd2 and PVC-d3. The frequencies of the CCI stretching modes of the polymers depended not only on the substituents in the trans position to the Cl atom across both adjacent C? C bonds, but also on the atom attached to the C atom of the C? Cl bond. The frequency shifts were used to assign the CCl stretching modes of PVC-βd1 and PVC-α,βd2 and to study the opening of the double bond of VC in the addition polymerization. The differences of the chemical shifts of the α and β protons of PVC due to the tacticity were determined experimentally by PVC-β,βd2 and PVC-αd1 without using the spin-decoupling technique. With PVC-α,βd2, the conception of the tetrad was required to interpret the four observed peaks whose intensities changed with the polymerization temperature and the trans–cis composition of the monomer used. 相似文献
244.
Masayuki Enomoto Yoshio Ito Tsutomu Katsuki Masaru Yamaguchi 《Tetrahedron letters》1985,26(10):1343-1344
Alkylation of lithiated -(benzyloxyacetyl)--2,5-bis(mehtoxyymethoxymethyl)- pyrrolidine proceeded with high stereoselectivity (≥96% de) and subsequent transformations of the alkylated products gave synthetically useful α-benzyloxy acids or α-hydroxy acids of high enantiomeric purity. 相似文献
245.
S. Enomoto 《Journal of polymer science. Part A, Polymer chemistry》1969,7(5):1255-1267
Polymerization of vinyl chloride (VC) was studied. natural evolution of HCl from VC occurred in the polymerization. VC, VC-αd1, VC-β,βd2 and VC-d3 were used to study the reactivities of the hydrogen atoms in the polymerization and the β-hydrogen atoms contributed to the chain transfer. Chemical and physical methods were used to observe irregular structures, such as branching, double bonds, and head-to-head or tail-to-tail addition, and also to confirm the relation between conversion and the irregular structures. 相似文献
246.
R. G. Weginwar Y. Kobayashi S. Ambe B. Liu S. Enomoto F. Ambe 《Journal of Radioanalytical and Nuclear Chemistry》1996,210(1):45-54
Separation of Au(III) and various carrier-free radionuclides by solvent extraction was investigated using an Au target irradiated by an energetic heavy-ion beam. Percentage extraction of Au(III) and coextraction of the radionuclides were determined with varying parameters such as kinds of solvent, molarity of HCl or pH, and Au concentration. Under the conditions where Au(III) was effectively extracted, namely extraction with ethyl acetate or isobutyl methyl ketone from 3 mol·dm–3 HCl, carrier-free radionuclides of many elements were found to be more or less coextracted. Coextraction of radionuclides of some elements was found to increase with an increase in the concentration of Au(III). This finding is ascribed to the formation of strong association of the complex of these elements with chloroauric acid. In order to avoid serious loss of these elements by the extraction, lowering of the Au(III) concentration or the use of a masking agent such as sodium citrate is necessary. Gold(III) was shown to be effectively back extracted with a 0.1 mol·dm–3 aqueous solution of 2-amino-2-hydroxymethyl-1,3-propanediol. Thus, a radiochemical procedure has been established for preparing a carrier-free multitracer and an Au tracer with carrier form from an Au target irradiated with a heavy-ion beam. Both tracers are now used individually for chemical and biological experiments. 相似文献
247.
Naoyuki Ishida 《Colloids and surfaces. A, Physicochemical and engineering aspects》2007,300(3):293-299
Direct measurements of the interaction forces between a spherical silica particle and a small air bubble have been conducted in aqueous electrolyte solutions by using an atomic force microscope (AFM). The silica particle was hydrophobized with a silanating reagent, and the interaction forces were measured by using several particles with different surface hydrophobicities. In the measured force curves, a repulsive force was observed at large separation distances as the particle moved towards the bubble. The origin of the repulsive force was attributed to an electrostatic double-layer force because both the particle and bubble were negatively charged. After the repulsive force, an extremely long-range attractive force acted between the surfaces. These results indicate that the intervening thin water film between the particle and bubble rapidly collapsed, resulting in the particle penetrating the bubble.
The instability of the thin water film between the surfaces suggests the existence of an additional attractive force. By comparing the repulsive forces of the obtained force curves with the DLVO theory, the rupture thickness was estimated. The hydrophobicity of the particle did not significantly change the rupture thickness, whereas the pH of the solution is considered to be a critical factor. 相似文献
248.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson H Bintinger DL Blumenfeld BJ Bobbink GJ Bross AD Buchanan CD Buijs A Cain MP Caldwell DO Chamberlain O Chien C Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Eisner AM Enomoto R Erne FC Fujii T Gabioud B Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Joshi UP Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG 《Physical review letters》1986,57(1):51-54
249.
Hikoe Enomoto 《Graphs and Combinatorics》1986,2(1):37-42
In a paper with the same title [3], we proved Chvátal's conjecture thatk-tough graphs havek-factors if they satisfy trivial necessary conditions. In this paper, we prove the following stronger result: Suppose|V(G)| k + 1,k |V(G)| even, and|S| k w(G – S) – 7/8k ifw(G – S) 2, wherew(G – S) is the number of connected components ofG – S. ThenG has ak-factor. 相似文献
250.
Computational calculations of Becke's three-parameter hybrid method using the LYP correlation functional (B3LYP) have been performed on (B12H12)2− dodecaborane anions with different boron isotopic compositions. This was done in order to investigate isotopic dependence of vibrational spectral properties of B12 icosahedra, and for comparison of the optical vibrational properties of the icosahedral molecule with the characteristics of inter- or intra-icosahedral optical phonon vibrational modes in boron-rich crystals. 相似文献