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41.
It was tried to prepare hybrid microcapsules composed of porous inorganic particles and epoxy resin shell and to apply to the self‐healing agent. A water soluble imidazole of gelation promoting agent as the core material was microencapsulated in the porous inorganic particles, which were coated with epoxy resin. The porous inorganic particles were prepared with the interfacial reaction between sodium silicate and calcium ion in the (W/O) dispersion. In the experiment, the concentration of sodium silicate and the mixing speed to form the (W/O) dispersion were mainly changed. The porous inorganic particles were immersed in the aqueous solution dissolving imidazole and then, added in the corn oil dissolving epoxy resin to be microencapsulated with gelated epoxy resin. The hybrid microcapsules containing imidazole with the mean diameters from 200 to 400 µm were able to be prepared and to induce the gelation reaction of epoxy resin by breaking the hybrid microcapsule shell due to heating. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
42.
Nine new secoiridoid glucosides from Jasminum nudiflorum 总被引:2,自引:0,他引:2
Takenaka Y Tanahashi T Taguchi H Nagakura N Nish T 《Chemical & pharmaceutical bulletin》2002,50(3):384-389
Phytochemical study of the leaves of Jasminum nudiflorum has led to the isolation of nine new secoiridoid glucosides, jasnudiflosides F-L (1-7), nudifloside D (8) and isooleoacteoside (9). The structures of these compounds were elucidated on the basis of chemical and spectroscopic evidence. 相似文献
43.
[reaction: see text] Radical cascade reaction with various 1,4-dienes and 1,4-enynes using dimethyl 2-(iodomethyl)cyclopropane-1,1-dicarboxylate as a homoallyl radical precursor smoothly proceeds through an iodine atom transfer mechanism to give functionalized bicyclo[3.3.0]octane derivatives in good yields. 相似文献
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46.
Joichi Koga Keisuke Taguchi Nobuhiko Kuroki Kenzo Konishi 《Colloid and polymer science》1967,215(1):45-47
Summary Some organic acids, alcohol and amine which have an asymmetric carbon atom were used for an investigation of asymmetric absorption
on wool. Racemic mixture of hydratropic acid, mandelic acid andα-phenethylamine have shown the selective absorption on wool from their aqueous and alcoholic aqueous solutions and S-form
of their diastereoisomers preferentially absorbed on wool. According to the results we obtained so far, it is concluded that
the preferential absorption strongly depends on the configuration of the substance of which wool is composed. 相似文献
47.
Specific heat has been investigated in a layered nitride superconductor, Li(0.12)ZrNCl, with T(c)=12.7 K. The obtained data have shown a marked dichotomy: The specific heat jump at T(c) (DeltaC/gamma(n)T(c)=1.8) and the superconducting gap ratio (2Delta/k(B)T(c)=4.6-5.2) have indicated an intermediate to a strong coupling of electrons, while the upper limit of the electron-phonon coupling constant lambda has directly been estimated to be 0.22, which belongs to a weak coupling regime. Furthermore, the rapid increase of gamma as a function of magnetic field suggests that the present material has an anisotropic s wave gap. 相似文献
48.
Haverkort MW Hu Z Tanaka A Ghiringhelli G Roth H Cwik M Lorenz T Schüssler-Langeheine C Streltsov SV Mylnikova AS Anisimov VI de Nadai C Brookes NB Hsieh HH Lin HJ Chen CT Mizokawa T Taguchi Y Tokura Y Khomskii DI Tjeng LH 《Physical review letters》2005,94(5):056401
Utilizing a sum rule in a spin-resolved photoelectron spectroscopic experiment with circularly polarized light, we show that the orbital moment in LaTiO3 is strongly reduced from its ionic value, both below and above the Ne el temperature. Using Ti L2,3 x-ray absorption spectroscopy as a local probe, we found that the crystal-field splitting in the t2g subshell is about 0.12-0.30 eV. This large splitting does not facilitate the formation of an orbital liquid. 相似文献
49.
Horiba K Taguchi M Chainani A Takata Y Ikenaga E Miwa D Nishino Y Tamasaku K Awaji M Takeuchi A Yabashi M Namatame H Taniguchi M Kumigashira H Oshima M Lippmaa M Kawasaki M Koinuma H Kobayashi K Ishikawa T Shin S 《Physical review letters》2004,93(23):236401
Using hard x-ray (HX; hnu=5.95 keV) synchrotron photoemission spectroscopy (PES), we study the intrinsic electronic structure of La(1-x)Sr(x)MnO(3) (LSMO) thin films. Comparison of Mn 2p core-levels with soft x-ray (SX; hnu approximately 1000 eV) PES shows a clear additional well-screened feature only in HX PES. Takeoff-angle dependent data indicate its bulk (> or =20 A) character. The doping and temperature dependence track the ferromagnetism and metallicity of the LSMO series. Cluster model calculations including charge transfer from doping-induced states show good agreement, confirming this picture of bulk properties reflected in Mn 2p core-levels using HX PES. 相似文献
50.
Kitagawa O Miyaji S Yamada Y Fujiwara H Taguchi T 《The Journal of organic chemistry》2003,68(8):3184-3189
Treatment of N-tosyliodoaziridine derivatives with Et(3)B efficiently produces various azahomoallyl radical (2-akenylamidyl radical) species which give oxygen-functionalized pyrrolidine derivatives through iodine atom transfer [3 + 2] cycloaddition with electron-rich alkenes such as enol ethers and ketene acetal. The present cycloaddition reaction proceeds regioselectively via C-N bond cleavage of an aziridinylalkyl radical intermediate and addition of the resulting azahomoallyl radicals to the terminal carbon of an alkene. The reaction of alkenes with the cyclohexenylamidyl radical generated from an optically active bicyclic iodoaziridine [(1S,2S,6S)-2-iodo-7-(p-toluenesulfonyl)-7-azabicyclo[4.1.0]heptane, 94% ee] also proceeds to give optically active octahydroindole derivatives (84-93% ee). 相似文献