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61.
We describe the dopant dependence of Raman gain in germanium- and fluorine-doped optical fibers. We clarify, both theoretically and experimentally, the effective Raman gain characteristic in an optical fiber, which is closely related to the fiber's refractive-index profile and electromagnetic field profile. We also show that this experimentally determined relationship can be used to evaluate the effective Raman gain characteristic in a germaninum- or a fluorine-doped optical fiber with an arbitrary index profile. 相似文献
62.
Yamada K Kurokawa T Tokuyama H Fukuyama T 《Journal of the American Chemical Society》2003,125(22):6630-6631
The total synthesis of (+)-duocarmycin A and SA through a common indoline intermediate is described. The key reactions include selective lithiation of a 2,6-dibromoiodobenzene derivative and diastereoselective addition to a chiral nitroalkene, copper-mediated aryl amination, and addition of aryllithium to azlactones. 相似文献
63.
The direct alpha-bromination of various ketones using trifluoromethanesulfonic anhydride and Grignard reagent or magnesium bromide in ether gave the corresponding alpha-bromo ketones in moderate to good yields under mild reaction conditions. 相似文献
64.
65.
Yuko Ikeda Youichi Kurokawa Koji Nakane Nobuo Ogata 《Cellulose (London, England)》2002,9(3-4):369-379
We developed a new entrap-immobilization method, using a gel formationof cellulose acetate and metal (Ti, Zr) alkoxide. Several biocatalysts(-galactosidase, -chymotrypsine, invertase, urease, lipase andSaccharomyces cereviciae) were successfullyentrap-immobilized on this composite gel fiber. The immobilization process wassimple and the resultant immobilized biocatalysts on the gel fiber were easy tohandle. It is considered that the biocatalysts are physically entrapped amongthe gel networks and distribute throughout the gel fiber. The gel fiber wasstable in phosphate buffer solution, electrolyte solution and organic solvent,because the gel formation was due to coordination interaction between celluloseand transition metal. Therefore, it can be applicable as a support for abiotransformation in various reaction media. We examined some enzyme reactionsand biotransformation using the immobilized biocatalysts on this gel fiber andevaluated this immobilization matrix in the reactions compared to the resultsobtained by the other immobilization method. The immobilized biocatalyst showedstable activity for repeated cycles and over a long period of time. Moreover,continuous reaction could be carried out in a column reactor packed with thisimmobilized biocatalyst. 相似文献
66.
Au and Ag nanometer-size particle-doped alumina films were prepared by the aqueous sol–gel method. Their XPS and third-order nonlinear optical properties were examined. The XPS results gave evidence of an interaction between Au and alumina. Third-order susceptibilities, χ(3) and χ(3)/ obtained by degenerate four-wave mixing method were in the order of 10−8 esu and 10−10 esu.cm for doped films, respectively. 相似文献
67.
Masafumi Jinno Hisayoshi Kurokawa Masaharu Aono Hideki Ninomiya 《Czechoslovak Journal of Physics》2000,50(3):433-439
The similarity of the abundance of heavy nuclei in the Universe with that of the nuclei produced in the fully reproducible reactions of protons in host metals like palladium, nickel or others is evident and can be described by the same exponential function of the distribution probability N(Z) depending on the proton number Z of the nuclides. This agrees with the earlier derived consequence of a 3
n
relation for magic numbers and an alternative foundation of the nuclear shell model. Compared to femtometer-attosecond reactions in the big bang, the low energy nuclear reactions in the host metals have picometer distances and megasecond duration. For this picometer distance, a combination of the swimming electron layer and Debye screening model with a metal-plasma dielectric model is presented. 相似文献
68.
69.
We study gamma and sine functions attached to a finite dimensional linear representation of a Lie group including their multiple versions via zeta regularizations. These definitions allow us to understand several multiple gamma and sine functions known so far, such as Barnes' gamma functions, Shintani's sine functions, and their q-analogues, in a unified way. Further, we discuss period integrals for such gamma functions. 相似文献
70.
Masashi Ban Keiko Kurokawa Rei Momose Osamu Hirota 《International Journal of Theoretical Physics》1997,36(6):1269-1288
An optimum quantum measurement that minimizes the average probability of error is considered for symmetric quantum states.
The positive operator-valued measure (POM) which satisfies the necessary and sufficient condition for the minimization of
the average probability of error is derived by using the quantum Bayes strategy. It is also shown that the mutual information
obtained in the optimum quantum measurement becomes extremum. Furthermore, an optimum quantum measurement for parameter estimation
is found for symmetric quantum states by applying the maximum-likelihood estimation. The optimum POM for the parameter estimation
has the same structure as that for the quantum state discrimination. 相似文献