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31.
10Gbit/s time-spread/wavelength-hop optical code generation and decoding are performed by dispersion-compensating fiber Bragg grating (FBG) en/decoder pair. Error-free 10km single mode fiber (SMF) transmission of 10Gbit/s optical code division multiplexing (OCDM) has been experimentally demonstrated. 相似文献
32.
Yuuki Hirayama Kentaro Yamaguchi Shigeru Sakamoto Michiko Iwamura 《Tetrahedron letters》2005,46(6):1027-1030
A new AB2 type building block for synthesis of dendritic compounds is made starting from Michael addition of 2 equiv of 3-hydroxyacetophenone to acrylate, followed by decarboxylation and deprotection of either carboxyl or hydroxyl protecting groups. [G1]-[G4] dendrons and [G2] dendrimer were synthesized by the reiterative [hydrogenolysis then DCC/DPTS coupling] sequence using a combination of convergent and divergent growth methods. 相似文献
33.
The titanium(IV) chloride-mediated aldol condensation between title compounds proceeds with high diastereoselectivity (Cram) to give exclusively (99% purity). 相似文献
34.
A note on chance constrained programming with fuzzy coefficients 总被引:17,自引:0,他引:17
This paper deals with nonlinear chance constrained programming as well as multiobjective case and goal programming with fuzzy coefficients occurring in not only constraints but also objectives. We also present a fuzzy simulation technique for handling fuzzy objective constraints and fuzzy goal constraints. Finally, a fuzzy simulation based genetic algorithm is employed to solve a numerical example. 相似文献
35.
M Hori T Iwamura T Morita E Imai H Oji T Kataoka H Shimizu M Ban M Nozaki M Niwa 《Chemical & pharmaceutical bulletin》1989,37(8):2222-2224
Synthesis of 3-cyclopropylmethyl-, 3-cyclobutylmethyl-, and 3-methyl-8-benzoylthio-2,6-methano-3-benzazocines (1j-l) was performed by regio-selective chlorosulfonation of non-narcotic 8-deoxy derivatives (1a-c) followed by reduction and benzoylation. 3-Benzoylthiomorphinans (2h-j) were also obtained by the same method. Compounds having small-ring substituents (1k, 1l, 2i, 2j) were found to be weak but pure mu- and delta-opioid antagonists. The analgetic activity of 1k was almost equal to that of pentazocine. 相似文献
36.
M Hori T Iwamura E Imai H Shimizu T Kataoka M Nozaki M Niwa H Fujimura 《Chemical & pharmaceutical bulletin》1989,37(5):1245-1248
3-Acylthiomorphinans, 3-carbamoylthio-3-deoxydihydromorphine and 3-benzoylthio-9-aza-17-carbamorphinan were synthesized by Newman-Kwart rearrangement of the corresponding O-thiocarbamates. The analgetic activities were lower than that of pentazocine, and the opioid receptor binding affinities were very weak. These acylthiomorphinans showed low antinociceptive activity compared with corresponding sulfur-containing benzomorphans. 3-Carbamoylthio-deoxydihydromorphine had no significant analgetic activity. 相似文献
37.
Hirayama Y Nakamura T Uehara S Sakamoto Y Yamaguchi K Sei Y Iwamura M 《Organic letters》2005,7(4):525-528
New aliphatic polyester-type dendrimers were synthesized using a new AB2-type building block 3, prepared from benzyl acetoacetate and 2 equiv of tert-butyl acrylate by acetoacetic acid ester synthesis. The reiterative [deprotection by HCO2H, then EDCI/DMAP coupling] sequence using divergent growth method gave [G1]-4tBu-[G5]-64tBu dendrimers. 13C NMR relaxation time (T1) measurements on the carboxy carbons show that the extended chain conformations are predominant in CDCl3. [structure: see text] 相似文献
38.
39.
Hiizu Iwamura Hiroshi Kihara Soichi Misumi Yoshiteru Sakata Teruo Umemoto 《Tetrahedron》1978,34(23):3427-3434
Various modes of the out-of-plane deformation of a benzene ring have been examined theoretically the MINDO/2 methods. Deformation to the boat conformation is predicted to be more facile than that to the half-boat or the chair conformation as observed in triple-layered[2.2]-metacyclophanes. The energy partitioning analysis reveals that a minimal loss of resonance energy at the gunwale of benzene boats appears to be responsible for the ease of boat deformations. The out-of-plane bending of the H atom at the bow of die benzene boats is coupled to the displacement of the H at the gunwale in such a way that the torsion of the bond between the bow and gunwale C atoms may be kept as small as possible. 相似文献
40.
Munehide Ishiguro Katsuya Nakaishi Tomo Nakajima 《Colloids and surfaces. A, Physicochemical and engineering aspects》2003,230(1-3):81-88
Acid rain is supposed to influence soil structures, because soils have pH-dependent charges. The adverse effects of acid rain on soils must be assessed. Although repulsive potential energy among soil clay particles generates swelling and dispersion, thereby changing the soil’s hydraulic conductivity, the relationship between hydraulic conductivity and repulsive potential energy has not been evaluated. Moreover, research into repulsive potential energy in multivalent counterionic systems has been rare. In this paper, repulsive potential energies for a volcanic ash soil (allophanic Andisol), which is characterized by a number of pH-dependent charges, were evaluated in a multivalent counterionic system. Changes in saturated hydraulic conductivity (K) of volcanic ash soil during dilute acid leaching and their relationship with the repulsive potential energies were examined. When nitric acid at pH 3 or 4 was leached, K decreased rapidly. On the other hand, the decrease in K attenuated as the proportion of sulfate in the dilute acid increased. Electrophoretic mobilities were measured and the zeta potentials were estimated. From the zeta potentials and the calculation of repulsive potential energies between the clay particles in the NO3–SO4 system, we concluded that the decrease in K for an acid solution with a high proportion of nitrate was due to swelling and dispersion of the soil induced by electrostatic repulsive potential energy. Because sulfate formed complexes on the clay surface, the repulsive potential energy decreased as the proportion of sulfate in the dilute acid increased. Then, the flocculation of the soil was maintained, thereby inhibiting the decrease in K. 相似文献