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121.
An imaging method for partially coherent objects is proposed by the aid of the propagation law of mutual intensity, and it can be reduced to principles used in holography and radio astronomy if the coherence reaches the both extremes, i.e., perfect coherence and complete incoherence, respectively. 相似文献
122.
Takio Y Pasqualetti M Kuraku S Hirano S Rijli FM Kuratani S 《Nature》2004,429(6989):1 p following 262
123.
James R. Evans Shigeru Tsubakitani 《The Journal of the Operational Research Society》1993,44(2):175-184
We investigate the application of Benders' partitioning to a mixed integer programming formulation of the segregated storage problem. The dual subproblem reduces to an efficiently-solvable network flow problem. This approach is compared empirically to Neebe's multiplier adjustment procedure. Benders' procedure is shown to be computationally effective for an important class of practical applications having high demand-to-capacity ratios and fewer products than compartments. 相似文献
124.
Shingo Sato Hironobu Kumagai Shigeru Matsuba Toshihiro Kumazawa Jun-Ichi Onodera Masanobu Suzuki 《Journal of heterocyclic chemistry》1999,36(5):1345-1347
A flavanone, in which a hydroxyl group at the 5-position was protected with a methyl group, converted to the corresponding 5-methoxy-2-phenyl-4-quinolone via flavylium salt under mild conditions. Flavanone-O-rhamnoglucoside, naringin, was also converted to 5-methoxy-2-phenyl-4-quinolon-7-O-rhamnoglucoside in the same way in an overall 25% yield. 相似文献
125.
Shigeru Yabumoto Kiyoshi Ishii Koichiro Arita 《Journal of polymer science. Part A, Polymer chemistry》1969,7(7):1577-1588
Copolymerization of acrylonitrile with styrene spontaneously occurred on addition of zinc chloride without addition of any other radical initiator. The composition of the copolymer approached that of strictly alternating copolymer as zinc chloride added to the copolymerization system increased. The significance of the apparent monomer reactivity ratios of this copolymerization system was studied from a kinetic point of view, and it was shown that the monomer sequence distribution is indicated by the apparent monomer reactivity ratios. Further, equations which represent the relation between the apparent monomer reactivity ratios and Q,e values at a given salt concentration were derived. These equations reasonably accounted for the decrease of the apparent monomer reactivity ratios of the copolymerization of acrylonitrile with styrene in the presence of zinc chloride and the behavior of the other acrylonitrile copolymerization systems in the presence of zinc chloride. The initiation step of the spontaneous radical copolymerization of acrylonitrile with styrene in the presence of zinc chloride was explained by a cross-initiation mechanism. 相似文献
126.
Hiroshi Kashiwagi Toshikazu Takada Shigeru Obara Eisaku Miyoshi Kimio Ohno 《International journal of quantum chemistry》1978,14(1):13-27
Ab initio LCAO SCF MO calculations are carried out on planar Co-porphine with a basis set of roughly double zeta quality for Co and N and of single zeta quality for C and H. The net charge on Co and N and the overlap population between them are 1.78, ?0.57, and 0.06, respectively, in the 2A1g, state, which is known to be the ground state by experiment. The bonding in this complex is thus largely ionic. The first and second calculated ionization potentials are 6.51 and 6.77 eV, respectively, and are in reasonable agreement with the observed ionization potentials of 6.44 and 6.62 eV for Ni-tetraphenylporphine. CI calculations within the framework of the ligand field theory are also performed. The calculated order of the five lowest states is 4B2g ≈ 4Eg, 4A2g, 2A1g, 4Eg from below and is not in agreement with the semiempirical order of 2A1g ≈ 4B2G, 4A2g, 2Eg, 4Eg determined by Lin. 相似文献
127.
Shirakawa E Yamagami T Kimura T Yamaguchi S Hayashi T 《Journal of the American Chemical Society》2005,127(49):17164-17165
Iron and copper complexes cooperatively catalyzed the arylmagnesiation of unfunctionalized alkynes including dialkylacetylenes, where the presence of both iron and copper catalysts is essential for high yields of 2-aryl-1-alkenylmagnesium bromides. 相似文献
128.
129.
Yoshiyuki Kani Shigeru Ohba Mami Kunita Yuzo Nishida 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e198-e198
The title mononuclear copper(II) complex, [CuCl(C18H26N4)]ClO4, shows a square‐pyramidal coordination with the diethylamino N atom at the apical position. Large anisotropies in the displacement parameters of the non‐H atoms of the ligand seem to be due to rotational disorder of the ClO4? anion. 相似文献