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We fabricate mesoporous silica/epoxy polymer composites through a solvent evaporation process. The easy penetration of the epoxy polymers into mesopores is achieved by using a diluted polymer solution including a volatile organic solvent. After the complete solvent evaporation, around 90% of the mesopores are estimated to be filled with the epoxy polymer chains. Here we carefully investigate the thermal expansion behavior of the obtained mesoporous silica/polymer composites. Thermal mechanical analysis (TMA) charts revealed that coefficient of linear thermal expansion (CTE) gradually decreases, as the amount of the doped mesoporous silica increases. Compared with spherical silica particle without mesopores, mesoporous silica particles show a greater effect on lowering the CTE values. Interestingly, it is found that the CTE values are proportionally decreased with the decrease of the total amount of the polymers outside the mesopores. These data demonstrate that polymers embedded inside the mesopores become thermally stable, and do not greatly contribute to the thermal expansion behavior of the composites. 相似文献
44.
Norihiro Kamide 《Mathematical Logic Quarterly》2005,51(6):579-585
The logic just corresponding to (non‐commutative) involutive quantales, which was introduced by Wendy MacCaull, is reconsidered in order to obtain a cut‐free sequent calculus formulation, and the completeness theorem (with respect to the involutive quantale model ) for this logic is proved using a new admissible rule. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
45.
Norihiro Kamide 《International Journal of Theoretical Physics》2005,44(4):399-428
Completeness and cut-elimination theorems are proved for some Gentzen-type sequent calculi which are closely related to non-commutative involutive quantales. 相似文献
46.
Peter Cirkel Takashi Kato Norihiro Mizoshita Henri Jagt Kenji Hanabusa 《Liquid crystals》2004,31(12):1649-1653
Liquid crystalline physical gels have been prepared in a super twisted nematic configuration. These gels show a remarkable increase in switching speed from the in field to out of field relaxation. We explore whether these gels might be used in fast passive matrix displays. 相似文献
47.
Non-stereospecific ring expansions of 3-acetylbenzothiazoline sulfoxides to benzothiazines from the reaction with acetic anhydride are reported. 相似文献
48.
Ochiai M Nishi Y Mori T Tada N Suefuji T Frohn HJ 《Journal of the American Chemical Society》2005,127(30):10460-10461
Reported here for the first time are the synthesis, isolation, and characterization of hypervalent beta-haloalkenyl-lambda3-bromanes. Exposure of terminal alkynes to p-trifluoromethylphenyl(difluoro)-lambda3-bromane activated by BF3-i-Pr2O resulted in fluoro-lambda3-bromanation of the triple bonds in a Markovnikov fashion, yielding (E)-beta-fluoroalkenyl-lambda3-bromanes stereoselectively in good yields. 5-Chloro-1-pentynes undergo domino lambda3-bromanation-chlorine shift-fluorination or lambda3-bromanation-chlorine shift-alkyl shift-fluorination reaction, depending on the substituents and afford (E)-beta-chloroalkenyl-lambda3-bromanes stereoselectively in high yields. The beta-chloroalkenyl-lambda3-bromanes contain three kinds of halogen atoms, F, Cl, and Br, in the molecule. 相似文献
49.
Exposure of 1-alkynyl[p-(trifluoromethyl)phenyl](tetrafluoroborato)-lambda3-bromanes to 2-mercaptobenzimidazole or benzothiazole in dichloromethane at 0 degrees C under argon resulted in a domino Michael addition-carbene rearrangement-cyclization reaction to produce directly tricyclic heterocycles in high yields, whereas the reaction with 2-mercaptobenzoxazole afforded 1-alkynyl sulfides. 相似文献
50.
The "flexible" 3 and "rigid" cyclic viologens 4, diquarternary salts of 2,2'-bipyridine and 1,10-phenanthroline, respectively, were treated with tributylphosphine (1) in acetonitrile containing a large amount of methanol under an argon atmosphere. A single electron transfer (SET) easily occurred from the latter to the former, the SET to 4 being 10(5)-10(6) times faster than the SET to 3. The reorganization energy lambda for the latter SET is thought to be larger than that for the former SET, because 3 undergoes a structural change upon the one-electron reduction to its radical cation, whereas the one-electron reduction of 4 takes place without a structural change. Taking into account the difference in lambda, and also taking into account the bond formation energy brought about by the follow-up reaction of the phosphine radical cation 1*(+) with methanol, the observed kinetics were well interpreted in terms of the Marcus theory. 相似文献