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81.
82.
Takuya?Satoh Thomas?Lottermoser Manfred?FiebigEmail author 《Applied physics. B, Lasers and optics》2004,79(6):701-706
Resonance-enhanced sum-frequency generation is introduced as a novel tool for investigation of magnetically ordered compounds. A tunable laser at frequency 1 is used to excite an intermediate electronic transition resonantly while a second laser at frequency 2 is used to scan the nonlinear spectrum at 1+2. The technique is particularly useful for investigation of centrosymmetric compounds since resonance enhancement at 1 leads to large nonlinear signals even in the case of weakly allowed nonlinear processes. The technique is demonstrated on antiferromagnetic NiO and KNiF3 and also shown to be useful for investigation of samples with large thickness or absorption. PACS 42.65.Ky; 78.20.Ls; 42.62.FiThis revised version was published in October 2004 with a correction to the name of Takuya Satoh. 相似文献
83.
We theoretically study the mechanical interaction between radiation and a semiconductor nanoparticle, based on a microscopic model of confined excitons. The exerted force is calculated by using the Maxwell stress tensor expressed in terms of the microscopic response field. The numerical demonstrations clarify the following: (1) The enhancement of the force by using electronic resonance is remarkable for a particle with a radius of less than 100 nm for semiconductor materials. (2) The spectral peak position of the exerted force is considerably sensitive to nanoscale-size changes which would be useful for highly accurate size-selective manipulation. 相似文献
84.
85.
We show that the Nomura algebra of the nonsymmetric Hadamard model coincides with the Bose–Mesner algebra of the directed Hadamard graph. 相似文献
86.
Kazuhiro Nagata Daisuke Sano Yu Shimizu Michiko Miyazaki Takuya Kanemitsu Takashi Itoh 《Tetrahedron: Asymmetry》2009,20(21):2530-2536
The catalytic asymmetric alkylation of α-cyanocarboxylates and acetoacetates with an alkyl halide was performed under phase-transfer conditions to afford compounds which have a chiral quaternary carbon with up to 97% and 94% ee, respectively. As applications of this method, chiral 2-oxindole derivatives and a β-lactam derivative were synthesized. 相似文献
87.
88.
89.
Kazuchika Ohta Hiroshi Ema Yasue Morizumi Takuya Watanabe Tetsuya Fujimoto Iwao Yamamoto 《Liquid crystals》1990,8(3):311-330
Two novel types of transition-metal-containing liquid crystals, bis(p-n-koxydithiobenzoato)nickel(II) (abbreviated as (CnO-DTB)2Ni), and (p-n-alkoxydithiobenzoato)(p-n-alkoxyperthiobenzoato)nickel(II) (abbreviated as (CnO-DTB)(CnO-PTB)Ni), were synthesized. It was found that the (CnO-DTB)2Ni complex for n = 8 has smectic H and C mesophases, and that the (CnO-DTB)2Ni complexes for n = 4 and 8 easily transform into the corresponding monoperthio complexes, nO-PTB)Ni, by heating at temperatures between 230°C and 285°C. It was confirmed that the transformation originates from an intermolecular reaction between the (CnO-DTB)2Ni complexes at high temperatures, and that the origin of the extra sulphurs in the resulting (CnO-DTB)(CnO-PTB)Ni complexes is the neighbouring (CnO-DTB)2Ni complexes. Interestingly, each of the (CnO-DTB)(CnO-PTB)Ni complexes (n = 4 and 8), has nematic mesophase and exhibits a unique double melting behaviour via the nematic phase, which is the first example in liquid crystals. The reversible transformation between the blue smectic rod-like (CnO-DTB)2Ni complex and the red nematic Λ-like (CnO-DTB)(CnO-PTB)Ni complex is possible. 相似文献
90.
Takuya Masuzawa 《International Journal of Game Theory》2008,37(2):185-201
In this paper, we discuss the computational complexity of the strategic cores of a class of n-person games defined by Masuzawa (Int J Game Theory 32:479–483, 2003), which includes economic situations with monotone externality.
We propose an algorithm for finding an α-core strategy of any game in this class which, counting the evaluation of a payoff
for a strategy profile as one step, terminates after O(n
3· M) operations, where M is the maximum size of a strategy set of any of the n players. The idea underlying this method is based on the property of reduced games.
This paper is based on a part of the doctoral dissertation of the author. The author thanks Mikio Nakayama, Masashi Umezawa,
William Thomson, an associate editor, and the anonymous referee for their helpful comments, suggestions, and advice. Thanks
are also due to Yukihiko Funaki for a comment that led the author to this subject. The author is responsible for errors and
inadvertencies. 相似文献