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71.
72.
LetX
* be the set of Pareto-optimal solutions of a multicriteria programming problem. We are interested in finding a vectorxX
* which minimizes another criterion. SinceX
* is a nonconvex set, our problem is that of minimization over a nonconvex set. By exploiting the fact that the number of criteria is often very small compared with the number of variables, we use a dual approach to obtain a practical algorithm. We report preliminary numerical results on problems with up to 100 variables and 5 criteria.The authors express their special thanks to Professor H. P. Benson and the referees for many valuable comments and suggestions and for pointing out valuable references. They also thank Dr. Y. Ishizuka for the references of Theorem 2.2. 相似文献
73.
74.
75.
T Kosuge M Yokota K Sugiyama T Mure H Yamazawa T Yamamoto 《Chemical & pharmaceutical bulletin》1985,33(12):5355-5357
76.
77.
Yokota Y Miyazaki A Fukui K Enoki T Hara M 《The journal of physical chemistry. B》2005,109(50):23779-23782
Electroactive tetrathiafulvalene thiol islands embedded in an n-alkanethiol SAM matrix were studied under potential control using in situ scanning tunneling microscopy. Unlike previously studied stochastic switching, the apparent height of the island could be intentionally controlled in the present system by choosing the appropriate potential and the island size. The dependence of the height change on the potential and the size is explained as structural change of the island induced by the charging effect of the electroactive moiety. 相似文献
78.
Kenji Yoshii Naoshi Ikeda Yusuke Yokota Yasuhiro Yoneda Yoichi Horibe 《Journal of solid state chemistry》2009,182(7):1611-1618
We have investigated the magnetic and dielectric properties of YbFe2−xMnxO4 (0?x?1), which is an Fe-site-substituted system of new multiferroic oxides RFe2O4 (R=Y, Ho-Lu). X-ray diffraction measurements show that a solid solution is formed between YbFe2O4 (x=0) and YbFeMnO4 (x=1) for 0?x?1, whereas only compounds with x=1 (i.e., RM1M2O4; M1 and M2=trivalent and divalent cations, respectively) have been known for the Fe-site substitution in RFe2O4. The valence of the Mn ion is determined to be ∼2+, consistently with the suppression of low-temperature magnetization by the Mn substitution. The magnetic transition temperature (TN) and the dielectric constant (ε′) decrease monotonically with increasing x. This result plausibly confirms that the magnetic and dielectric properties in oxides isostructural with RFe2O4 are governed by the electron transfer between Fe-site ions, unlike ordinary ferroelectrics and dielectrics, in which the ionic displacement plays a key role. The possibility for application is briefly discussed as well. 相似文献
79.
80.
A sequence-ordered, periodic copolymer of ethylene, ethylene, and acrylic acid, poly (ethylene-per-ethylene-per-acrylic acid) (PEEA), with M
w=1.44×105 has been synthesized by alternating copolymerization of 1,3-butadiene and methyl acrylate, followed by hydrogenation and
hydrolysis. Aqueous solution and dissociation properties of the alkali-soluble PEEA were explored by potentiometric titration
and intrinsic viscosity at 25 °C. The pH values of PEEA were almost constant (pH = 6.48 ∼ 6.55) with an increasing degree
of dissociation (α) from 0.3 to 0.8 at C
s=50 mN NaCl. Correspondingly, the plots of negative logarithm of apparent dissociation constant (pK
a) against α showed a reversed S-shape curve over the whole α, indicating an extensive precipitation and subsequent tran-sition
from compact to coiled conformation. The intrinsic viscosity steeply increased with α above 0.4 up to 9.97 dl/g at α = 1.0.
Good agreement between the observed electrostatic potential and that calculated from the rod model with a smeared charge density
was observed in the region of α higher than 0.9. The dissociation and dissolution processes of PEEA with neutralization in
water were described.
Received: 14 April 1998 Accepted: 3 June 1998 相似文献