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71.
Shigehiro Hirano Ko-Ichi Yamamoto Hiroshi Inui Ming Ji Min Zhang 《Macromolecular Symposia》1996,105(1):149-154
The following dry composite beads (diameter 1.0-1-2 mm) were prepared: chitin-CaCO3, chitosan-CaCl2. chitosan-CuCl2, partially N-acetylated chitosan-CuCl2, chitosan-CuSO4, chitosan-Fe3O4, chitin-SiO2. Each of chitosan-CuCl2, chitosan-CuSO4 and chitin-CaCl2 composite beads was treated in aqueous K2CO3 at room temperature to afford a mixture of metal carbonates and hydroxides on chitin or chitosan chain. 相似文献
72.
Ir(III)‐Catalyzed C7‐Position‐Selective Oxidative CH Alkenylation of Indolines with Alkenes in Air
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An efficient method for C7‐position‐selective alkenylation of N‐substituted indolines with alkenes is reported. Various 7‐alkenylindolines were obtained in moderate to excellent yields in air in the presence of catalytic amounts of [Cp*IrCl2]2, AgOTf, and Cu(OAc)2. The protocol relies on the use of a carbonyl or carbamoyl group on the nitrogen atom of indoline as a directing group and is potentially applicable to the synthesis of 7‐alkenylindoles and 7‐alkylindoles. 相似文献
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Masao Hirano Shigetaka Yakabe James H. Clark Hiroyuki Kudo Takashi Morimoto 《合成通讯》2013,43(10):1875-1886
A wide variety of sulphides can be readily converted to the corresponding sulphoxides in good to excellent yields by treatment with a combination of sodium chlorite, (salen)manganese(III) complex, and chromatographic alumina in dichloromethane under mild and neutral conditions. 相似文献
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Supramolecular polymer gels from polystyrene bearing cyclic amidine Group and acrylic acid/n‐butyl acrylate copolymers
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Mina Sakuragi Naoto Aoyagi Yoshio Furusho Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2016,54(6):765-770
We have prepared supramolecular polymer gels by mixing solutions of a polystyrene bearing cyclic amidine pendant groups (Poly‐A) and copolymers of acrylic acid and n‐butyl acrylate (Poly‐C), followed by evaporation. FT‐IR analysis indicated that the gels were formed through three‐dimensional network of the amidinium‐carboxylate salt bridge. DSC study showed that the Poly‐A and the Poly‐C were miscible when the salt bridge content was high. On the other hand, the mixtures with small salt bridge content showed phase separation. Dynamic shear measurements showed that the gel prepared from Poly‐A and Poly‐C with acrylic acid unit content of 15% had G' higher than G″ over a temperature range of ?22 °C to 32 °C, in which the G' value reached almost 1 MPa. The gel had a crossover point of G' and G″ at 32 °C, very close to room temperature, which suggested facile processability. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 765–770 相似文献
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Jensen P Odaka TE Kraemer WP Hirano T Bunker PR 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(4):763-794
We have developed a computational procedure, based on the variational method, for the calculation of the rovibronic energies of a triatomic molecule in an electronic state that become degenerate at the linear nuclear configuration. In such an electronic state the coupling caused by the electronic orbital angular momentum is very significant and it is called the Renner effect. We include it, and the effect of spin-orbit coupling, in our program. We have developed the procedure to the point where spectral line intensities can be calculated so that absorption and emission spectra can be simulated. In order to gain insight into the nature of the eigenfunctions, we have introduced and calculated the overall bending probability density function f(p) of the states. By projecting the eigenfunctions onto the Born-Oppenheimer basis, we have determined the probability density functions f+(rho) and f-(rho) associated with the individual Born-Oppenheimer states phi(-)elec and phi(+)elec. At a given temperature the Boltzmann averaged value of the f(p) over all the eigenstates gives the bending probability distribution function F(rho), and this can be related to the result of a Coulomb Explosion Imaging (CEI) experiment. We review our work and apply it to the molecules CH2+, MgNC and NH2, all of which are of astrophysical interest. 相似文献
80.
Novel ferromagnetism in Ca(1-x)La(x)B(6) is studied in terms of the Ginzburg-Landau theory for excitonic-order parameters, taking into account symmetry of the wave functions. We found that the minima of the free energy break both inversion and time-reversal symmetries, while the product of these two remains preserved. This explains various novelties of the ferromagnetism and predicts a number of magnetic properties, including the magnetoelectric effect, which can be tested experimentally. 相似文献