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31.
Ken-ichi Mimura Kosuke Hiramatsu Makoto Moriya Wataru Sakamoto Satoshi Kawado Yoshiaki Uesu Toshinobu Yogo 《Journal of nanoparticle research》2010,12(5):1933-1943
A transparent BaTiO3 particle/polymer hybrid was synthesized from a Ba–Ti double alkoxide modified with an organic ligand and its refractive index
and second harmonic generation were studied. BaTiO3 particles modified with 2-vinyloxyethanol (ethylene glycol monovinyl ether, EGMVE) were polymerized with methyl methacrylate
(MMA) yielding the transparent BaTiO3 particle/poly MMA hybrid. X-ray photoelectron spectra indicated that the formation of chemical bonds between BaTiO3 nanoparticles and the organic matrix. The refractive indexes of the hybrid films depended on the crystallite size of BaTiO3 nanoparticles and the volume fractions of BaTiO3 and polymer phases. The hybrid film synthesized at BaTiO3/8EGMVE/30H2O/PMMA revealed a refractive index of 1.65 at 589 nm with an Abbe number of 54. The hybrid film exhibited a second harmonic
wave of 532 nm on irradiation with a fundamental wave of 1,064 nm. 相似文献
32.
Rod-like assembled magnetite (Fe3O4) nanoparticles (NPs) were successfully synthesized in a one-pot process using a polysiloxane template derived from a dialkoxysilane. The assembly was constructed using the thiol-ene click reaction between thiol groups on the polysiloxane chain and allyl groups on Fe3O4 NPs. The thiol-containing polysiloxane chain and the allyl-containing Fe3O4 NPs were synthesized by the hydrolysis–condensation of 3-mercaptopropyl(dimethoxy)methylsilane and iron (III) allylacetylacetonate, respectively. Fe3O4 NPs of around 5 nm were uniformly dispersed on the siloxane rods and exhibited neither remanent magnetization nor coercivity. A fluid containing a dispersion of rod-like assembled Fe3O4 NPs showed yield stress even without the application of an external magnetic field, whereas spherical Fe3O4 NPs exhibited no yield stress. The rod-like assembled Fe3O4 NPs on anisotropic siloxane clearly exhibited typical magnetorheological behavior. 相似文献
33.
Kosaku Hirota Mitsuomi Shirahashi Shigeo Senda Motoi Yogo 《Journal of heterocyclic chemistry》1990,27(3):717-721
Several 6-substituted thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione derivatives were synthesized. 6-Ethoxycarbonyl derivatives 3 and 7 were prepared by treatment of 6-chloro-5-formyluracil 1 and 6-chloro-5-cyanouracil 6 with ethyl 2-mercaptoacetate in the presence of a base. Electrophilic substitution reactions (Vilsmeier-Haack reaction, bromination, and nitration) of 5,6-unsubstituted thieno[2,3-d]pyrimidine 9 , prepared by condensation of 6-mercaptouracil 8 with chloroacetaldehyde, afforded the corresponding 6-formyl-, 6-bromo-, and 6-nitrothieno[2,3-d]pyrimidines 10, 15 and 16 , respectively. 相似文献
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35.
Vladimir Tuboltsev Alexander Savin Wataru Sakamoto Atsushi Hieno Toshinobu Yogo Jyrki Räisänen 《Journal of nanoparticle research》2011,13(11):5603-5613
Multiferroics conventionally refer to the materials exhibiting co-existing electric, magnetic, and structure order parameters.
Interplay between ferroelectricity, magnetism, and ferroelasticity in a single phase makes multiferroics truly multifunctional
providing control over magnetic and electric ordering by applying electric and magnetic fields, respectively. Incorporation
of multiferroic-based components into nanoscale applications will enable additional degrees of freedom in manipulating with
spin and charge not easily attainable otherwise. Multiferroic bismuth ferrite lead titanate has been chemically synthesized
in form of nanocrystalline films. The morphology of the films revealed a single perovskite phase confined within crystalline
grains of few tens of nm in size. The films were found to exhibit ferroelectricity and ferromagnetism with characteristic
electric polarization and magnetization hysteresis loops, transformations associated with spin reorientation in an external
magnetic field and the spin-glassy behavior well above the room temperature. High degree of magnetic frustration and disorder
in the spin system spatially confined in the nanograins, distribution of the grains anisotropy axis, inter-grain interactions,
and the effects of uncompensated spins on the large effective surface/interface favored by the nanocrystalline morphology
were assumed to be responsible for the anomalous magnetic properties and glassy dynamics in the films. 相似文献
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37.
Organoboranes have been recently demonstrated to be highly versatile reagents and intermediates for organic synthesis.1 Several papers have been reported dealing with allenic or propargylic boranes for such purposes.2 On the other hand, organosilicon compounds have become increasingly important in synthetic chemistry.3 In search of finding novel synthetic applications by combination of organoboranes and organosilanes, we examined a synthesis of 1-alkynyl (trimethyl) silanes from trimethylsilylpropargyl phenyl ether and trialkylboranes. 相似文献
38.
H. Ogawa K. Asahi H. Ueno K. Sakai H. Miyoshi D. Kameda T. Suzuki H. Izumi N. Imai Y.X. Watanabe K. Yoneda N. Fukuda H. Watanabe A. Yoshimi W. Sato N. Aoi M. Nagakura T. Suga K Yogo A. Goto T. Honda Y. Kobayashi W.-D. Schmidt-Ott G. Neyens S. Teughels A. Yoshida T. Kubo M. Ishihara 《The European Physical Journal A - Hadrons and Nuclei》2002,13(1-2):81-85
The electric quadrupole moment of 17B and the g-factor of 17C were measured by using the fragmentation-induced nuclear polarization technique combined with the β-NMR method. The experimental
quadrupole moment of 17B is found strikingly close to that of the neutron closed-shell isotope 13B, indicating a strong quenching of the neutron E2 core-polarization charge. From the result obtained for the 17C g-factor, we can conclude that the ground-state spin-parity of 17C is 3/2+.
Received: 1 May 2001 / Accepted: 4 December 2001 相似文献
39.
A membrane-permeant malachite green-conjugated IP3 analog (MGIP3/PM) was synthesized as a probe for small molecule-based CALI (smCALI), and its effect on the Ca2+ signaling in intact DT40 chicken B cells was examined. In DT40 B cells treated with the smCALI probe, laser irradiation inhibited IP3-induced Ca2+ oscillations in response to B cell receptor stimulation, demonstrating that IP3R was acutely inactivated. We then applied smCALI to clarify the mechanism of capacitative Ca2+ entry (CCE), in which involvement of IP3R has been suggested. Despite the inactivation of IP3R by smCALI, thapsigargin-induced CCE remained unaffected, providing evidence that functional IP3R is not required for CCE in DT40 cells. These results demonstrate the potency of the smCALI technique for the study of the roles of IP3R in complex intracellular Ca2+ dynamics. 相似文献
40.
Sakamoto Wataru Kosugi Kana Arimoto Tadashi Yogo Toshinobu Hirano Shin-ichi 《Journal of Sol-Gel Science and Technology》1999,16(1-2):65-75
Highly oriented tungsten bronze K0.4(Pb0.6Ba0.4)0.8Nb2O6 ferroelectric thin films have been prepared from metal alkoxides and metal acetate by chemical process. The formation of solid solution with potassium was found to be very effective to form the tungsten bronze phase at lower temperatures compared with (Pb0.6Ba0.4)Nb2O6. The amount of potassium in the composition of Kx(Pb0.6Ba0.4)1 – x/2Nb2O6 [0 x 0.4] is also important to crystallize in the tungsten bronze phase. K0.4(Pb0.6Ba0.4)0.8Nb2O6 films with c-axis preferred orientation were successfully synthesized on MgO(1 0 0) and Pt(1 0 0)/MgO(1 0 0) substrates above 700°C. KPBN60 thin film on Pt(1 0 0)/MgO(1 0 0) showed a remnant polarization of 20 C/cm2 and a coercive field of 140 kV/cm at –150°C. 相似文献