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51.
Kazuhisa Makino 《Discrete Applied Mathematics》2010,158(18):2024-2030
Gopalan et al. studied in [P. Gopalan, P.G. Kolaitis, E.N. Maneva, C.H. Papadimitriou, The connectivity of Boolean satisfiability: computational and structural dichotomies, in: Proceedings of the 33rd International Colloquium on Automata, Languages and Programming, ICALP 2006, 2006, pp. 346-357] and [P. Gopalan, P.G. Kolaitis, E.N. Maneva, C.H. Papadimitriou, The connectivity of Boolean satisfiability: computational and structural dichotomies, SIAM J. Comput. 38 (6) (2009) 2330-2355] connectivity properties of the solution-space of Boolean formulas, and investigated complexity issues on the connectivity problems in Schaefer’s framework. A set S of logical relations is Schaefer if all relations in S are either bijunctive, Horn, dual Horn, or affine. They first conjectured that the connectivity problem for Schaefer is in P. We disprove their conjecture by showing that there exists a set S of Horn relations such that the connectivity problem for S is -complete. We also investigate a tractable aspect of Horn and dual Horn relations with respect to characteristic sets. 相似文献
52.
53.
A new tripodal fluorescent chemosensor 1 having amidepyridinium moiety as the key binding site and anthracene moiety as the sensing subunit was synthesized. In competitive polar organic solvent, this chemosensor 1 displayed high selectivity toward by formation of binding-induced excimer emission. 相似文献
54.
Kazuhisa Murata Masahiro Saito Isao Takahara Megumu Inaba 《Reaction Kinetics and Catalysis Letters》2008,93(1):51-58
Rhodium and cerium were found to be suitable additives for improving the sulfur-tolerance of Ni-based gasoline reforming catalysts.
In these cases, the Rh content was only 0.1 wt.% with 5 wt.% of Ce. The lifetime of Rh-Ce-modified Ni-based catalyst is found
to be above 600 hours at 1023K, which is over a ten times longer lifetime than that of the unmodified catalysts, when premium
gasoline was used. 相似文献
55.
We redox-regulated alpha-helicity of short peptides intramolecularly cross-linked with a ferrocenyl linker between amino acid side chains. The helical content of the cross-linked peptide was estimated to be 56% in the neutral state of the ferrocene core at 25 degrees C. The addition of an oxidant to the solution of the cross-linked peptide enhanced the helicity up to 75%. The increased helical content returned to the same level as that in the previous ferrocene state by further addition of a reductant. 相似文献
56.
57.
Simon Burk Markus Albrecht Kazuhisa Hiratani 《Journal of inclusion phenomena and macrocyclic chemistry》2008,61(3-4):353-359
A novel tripodand-type ligand (L1) having three 2,3-dihydroxynaphthalene end groups and a C3 symmetric 1,3,5-tryimethylbenzene based backbone was prepared by the reaction of 1,3,5-tris(bromomethyl)-2,4,6-trimethylbenzene with 3-(2-(hydroxymethyl)allyloxy)naphthalene-2-ol followed by triple Claisen rearrangement. A 1:1 titanium complex which acts as a metallo-cryptand is obtained by the reaction of ligand (L1) with Ti(IV)(=O)(acac)2 in the presence of base. The formation of the metallo-cryptand strongly depends on templating effects by counter cations and it shows a high selectively for the encapsulation of cesium cations in its cavity. 相似文献
58.
Shimizu H Fujimoto K Furusyo M Maeda H Nanai Y Mizuno K Inouye M 《The Journal of organic chemistry》2007,72(4):1530-1533
We newly prepared para- and meta-linked alkynylpyrene oligomers and examined their photophysical properties. Oligomerization of monomeric building blocks was performed by CuI-promoted oxidative coupling reaction. The resulting oligomers mainly consist of 2-mer to 6-mer that were assigned on the basis of MALDI-TOF mass spectra, and the 2-mer, 3-mer, and 4-mer were isolated and fully characterized. From their absorption and fluorescence spectra, the para-linked oligomers were found to be somewhat pi-conjugated compared with meta-linked ones, and the fluorescence quantum yields decreased with increasing oligomer length (Phif = 0.79-0.55). 相似文献
59.
Kazuhisa Yano Arimitsu Usuki Akane Okada 《Journal of polymer science. Part A, Polymer chemistry》1997,35(11):2289-2294
Polyimide-clay hybrid films with four different sizes of clay minerals have been synthesized to investigate the effect of the size of clay minerals to the properties of the hybrids. Hectrite, saponite, montmorillonite, and synthetic mica were used as clay minerals. Those clays consist of stacked silicate sheets about 460 Å (hectrite), 1650 Å (saponite), 2180 Å (montmorillonite), and 12300 Å (synthetic mica) in length, 10 Å in thickness. The longer the length of clay mineral was, the more effectively properties of polyimide were improved. In the case of polyimide-mica hybrid, only 2 wt % addition of synthetic mica brought permeability coefficients of water vapor to value less than one-tenth of that of ordinary unfilled polyimide, and thermal expansion coefficient was lowered at the level of 60% of the original one. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2289–2294, 1997 相似文献
60.
Takashi Nakamura Keiji Yashiro Kazuhisa Sato Junichiro Mizusaki 《Journal of solid state chemistry》2009,182(5):1121-299
In order to elucidate the relation between thermodynamic quantities, the defect structure, and the defect equilibrium in La2−xSrxNiO4+δ, statistical thermodynamic calculation is carried out and calculated results are compared to those obtained from experimental data. Partial molar enthalpy of oxygen and partial molar entropy of oxygen are obtained from δ-P(O2)-T relation by using Gibbs-Helmholtz equation. Statistical thermodynamic model is derived from defect equilibrium models proposed before by authors, localized electron model and delocalized electron model which could well explain the variation of oxygen content of La2−xSrxNiO4+δ. Although assumed defect species and their equilibrium are different, the results of thermodynamic calculation by localized electron model and delocalized electron model show minor difference. Calculated results by the both models agree with the thermodynamic quantities obtained from oxygen nonstoichiometry of La2−xSrxNiO4+δ. 相似文献