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111.
Yukihiro Tsutsumi 《Mathematische Zeitschrift》2004,246(1-2):167-175
A method for constructing hyperbolic knots each of which bounds accidental incompressible Seifert surfaces of arbitrarily high genus is given.
Mathematics Subject Classification (2000):57N10, 57M25.The author was supported in part by Research Fellowships of the Japan Society for the Promotion of Science for Young Scientists. 相似文献
112.
113.
A joint-transform phase correlation is made by an extracted phase from the joint power spectrum using a phase-shifting Mach-Zehnder
interferometer with a wavelength-shifted laser diode (LD), and then by numerically Fourier-transforming a measured phase.
The algorithm in six steps is insensitive to the power changes in an LD. The phase correlator gives the best discrimination
performance. Discriminative multiple-object recognition is performed with no intermodulation noise and artifact noise-free
correlation by arranging the multiple objects in a regularly equal-spaced array. The experimental and numerical results are
shown. 相似文献
114.
Yukihiro Mitsuda Takashige Fujikawa Katsumi Nakasaka Takahiro Uno Masataka Kubo Takahito Itoh 《Journal of polymer science. Part A, Polymer chemistry》2004,42(15):3800-3811
The spontaneous reactions of 1‐(2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione‐5‐ylidene)‐4‐(dicyanomethylene)‐2,5‐cyclohexadiene (QM‐1) with a vinyl ether, butyl vinyl ether (BVE), and a cyclic ketene acetal, 2‐methylene‐1,3‐dioxepane (MDOP), were investigated. The reaction of QM‐1 with BVE produced a terpolymer composed of QM‐1, 7‐butoxy‐8,8‐dicyanoquinodimethane, and BVE units as a hexane‐insoluble product and a one‐to‐one adduct of methylene Meldrum's acid and BVE as a hexane‐soluble product. The spontaneous reaction of QM‐1 with BVE produced, in the presence of 2,2,6,6‐tetramethylpiperidine‐1‐oxy (TEMPO), a terpolymer carrying TEMPO units in the chain ends, and in the presence of methanol, a one‐to‐one‐to‐one adduct of QM‐1, BVE, and methanol was isolated. The spontaneous reaction with bulkier, electron‐donating MDOP produced a low‐molecular‐weight alternating cooligomer of QM‐1 with MDOP. The spontaneous polymerization was proposed to proceed via a zwitterionic intermediate taking two forms, gauche and trans, depending on the bulkiness of the comonomer. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3800–3811, 2004 相似文献
115.
Hiroyoshi Kamogawa Yuichiro Haramoto Yukihiro Misaka Yasuhiro Asada Yumiko Ohno Masato Nanasawa 《Journal of polymer science. Part A, Polymer chemistry》1985,23(5):1517-1526
p-Styrenesulfonate esters of primary and secondary perfume alcohols and phenols, including citronellol, 1-menthol, borneol, β-phenethyl alcohol, eugenol, p-anisyl alcohol, cinnamyl alcohol, and geraniol, and herbicide alcohols such as 2,4-dichloro- and 2,4,5-trichlorophenoxy-ethanols were synthesized using p-styrenesulfonyl chloride in the presence of bases such as pyridine, triethylamine, sodium hydrogen carbonate, and sodium hydride. The hydrolytic behavior of sulfonate ester monomers and their copolymers with N-vinyl-2-pyrrolidone to liberate perfume and herbicide alcohols was structure-dependent, thereby affording chemical release control. 相似文献
116.
Fourier-transform (FF) Raman spectroscopy and chemometrics were used for nondestructive analysis of ivories. The discrimination of five kinds of ivories, two subspecies of African elephant, mammoth, hippopotamus, and sperm whale, was investigated, and a calibration model for predicting their specific gravity was developed. FT-Raman spectra were measured in situ for them and chemometrics analyses were carried out for the 3050-350 cm(-1) region. The five kinds of ivories were clearly discriminated from each other on the scores plots of two or three principal components (PCs) obtained by principal component analysis (PCA). The loadings plot for PC 1 shows that the discrimination relies on the content ratio of organic collagenous protein and inorganic hydroxyapatite of ivories. The loadings plot for PC 2 shows that bands due to the CH3 and CH2 stretching modes of the protein also play a role in the discrimination. Using partial least squares regression (PLSR), we developed a calibration model that predicts the specific gravity of the ivories from the FT-Raman spectra. The correlation coefficient and root mean square error of cross validation (RMSECV) of this model were 0.980 and 0.024, respectively. 相似文献
117.
Yukihiro Motoyama 《Tetrahedron》2005,61(43):10216-10226
Atom-transfer radical cyclization (ATRC) and addition (ATRA) catalyzed by a coordinatively unsaturated diruthenium amidinate complex 4, [(η5-C5Me5)Ru(μ2-i-PrNC(Me)Ni-Pr)Ru(η5-C5Me5)]+, are investigated, and their features are compared with those of atom-transfer radical polymerization (ATRP). As an example of ATRC, a cationic diruthenium amidinate 4 is found to exhibit excellent catalytic reactivity for the cyclization of N-allyl α-halogenated acetamides including an alkaloid skeleton at ambient temperature. A catalytic species generated in situ from a halide complex, (η5-C5Me5)Ru(μ2-i-PrNC(Me)Ni-Pr)Ru(η5-C5Me5)(X) [X=Cl, Br] and sodium salts of weakly coordinating anions such as NaPF6 and NaBPh4 also shows high catalytic activity; this actually provides a solution for a problematic instability of 4 as the practical catalyst. The in situ-generated catalyst species 4 is also active towards the intermolecular ATRA of α,α,γ-trichlorinated γ-lactam with alkenes at rt to afford the corresponding α-alkylated γ-lactams in moderate yields. Examination of ATRP of methyl methacrylate (MMA) showed that both the isolated 4 [Y=PF6] and in situ-generated 4 [Y=PF6] are effective for the polymerization of MMA in the presence of 2-bromoisobutylate as the initiator. Use of the isolated catalyst results in controlled polymerization at initial stage of the reaction; in contrast, the polymerization with in situ-generated catalyst produces poly(MMA) with wide molecular weight distribution. The isolated catalyst 4 is powerful for the activation of a C-Br bond of macromolecule initiators; BrCMe2CO2[O(CH2)4]n-n-Bu (Mn=3800; Mw/Mn=1.2) initiated ATRP of MMA even at 25 °C to afford the poly(THF)-poly(MMA) block copolymer of Mn=26,000 and Mw/Mn=1.2 with the aid of 4. The roles of the coordinatively unsaturated ruthenium species for these reactions are discussed. 相似文献
118.
Toshio Kinoshita Yukihiro Watanabe Setsuko Nakao Sunao Furukawa 《Journal of heterocyclic chemistry》1992,29(7):1785-1788
The following 5-nitro-2,4(1H,3H)-pyrimidinediones possessing bromo substituted side chains at the 1- and 6-positions were prepared by bromination of 3,6-dimethyl-1-(ω-hydroxyalkyl)-5-nitro-2,4(1H,3H)-pyrimidinediones 4a and 4b and its nitrates 2a and 2b . The three of mono-bromo derivatives are: 1-(ω-acetoxyalkyl and ω-hydroxyalkyl)-6-bromomethyl-3-methyl. 6a, 6b, 7a and 7b and 1-(ω-bromoalkyl)-3,6-dimethyl-2,4(1H,3H)- pyrimidinediones 8a and 8b . The one type dibromo derivatives are: 1-(ω-bromoalkyl)-6-bromomethyl-3-methyl-2,4(1H,3H)-pyrimidinediones 5a and 5b . 相似文献
119.
Masahiro Tsunooka Toshihiro Ueda Makoto Tanaka Hiroaki Egawa 《Journal of polymer science. Part A, Polymer chemistry》1984,22(9):2217-2225
Photocationic crosslinking of a poly(2,3-epithiopropyl methacrylate) (PETMA) film containing 4-N,N-diethylaminobenzene diazonium tetrafluoroborate (DAC) was investigated. Very rapid photocrosslinking of PETMA was observed and the rate was greater than that of poly(glycidyl methacrylate) with DAC. Post-heating of the irradiated PETMA film resulted in a decrease of the insoluble fraction. This decrease was explained by scission of crosslinking points by the BF3. In the present conditions, more than 0.3 wt % of DAC was required to insolubilize the PETMA film. Photopolymerizations of propylene sulfide (PS) and 2,3-epithiopropyl pivalate (ETPP) in the presence of DAC were investigated. The polymerization of PS proceeded smoothly but addition of ethyl acetate to PS depressed the rate and the degree of polymerization. ETPP could not be polymerized but copolymerized with PS by this method. Addition of ETPP to PS depressed both the rate of the polymerization and the degree of polymerization. From these results, it is deduced that the photocrosslinking of a PETMA film is caused by a cationic polymerization of episulfide groups but the chain length is not large. 相似文献
120.
Haruyuki Okamura Shogo Toda Masahiro Tsunooka Masamitsu Shirai 《Journal of polymer science. Part A, Polymer chemistry》2002,40(17):3055-3062
Photocrosslinkable systems with thermally cleavable properties based on blends of poly(vinyl phenol) (PVP) and diepoxides were investigated. Thermally cleavable diepoxides as crosslinkers were prepared and characterized. As a thermally cleavable linkage, a tertiary ester moiety was incorporated into the crosslinker molecule. PVP/crosslinker blended films containing photoacid generators (PAGs) became insoluble in solvents after UV irradiation and subsequent post‐exposure‐bake (PEB) treatment. With a rise in the PEB temperature, the insoluble fraction of the irradiated films increased, passed through a maximum value, decreased, and increased again at elevated baking temperatures. The insolubilization profiles of the irradiated films were complicated and strongly dependent on the type of PAG used, the structure of the crosslinkers, and the PVP/crosslinker ratio. A mechanism for the thermal degradation was studied with Fourier transform infrared spectroscopy. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3055–3062, 2002 相似文献