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51.
Toru Ikeda 《Geometriae Dedicata》2014,170(1):177-183
The aims of this paper is to prove that every closed connected orientable 3-manifold with an orientation-preserving periodic diffeomorphism contains infinitely many, setwise invariant, spatial graphs whose exteriors are hyperbolic 3-manifolds. 相似文献
52.
Hong Xia Yoshio Hashimoto Toru Morita Toshihiro Hirai 《Journal of Polymer Science.Polymer Physics》2014,52(13):887-892
Few solvents are capable of dissolving polyketones (PKs). 1,1,1,3,3,3‐Hexafluoro‐2‐propanol (hexafluoroisopropanol, HFIP) is a better solvent than trifluoroethanol and m‐cresol. When HFIP was evaporated from a PK/HFIP solution, a porous cast‐film with a microparticle structure was formed because the isotactic PKs adopted a helical conformation, and convection during evaporation of the high polarity and low‐boiling‐point HFIP caused aggregation and rolling of the polymer molecules. The addition of plasticizer suppressed particle formation, improving the surface structure and mechanical properties of the film. In particular, the dielectric properties of the film improved significantly. This will enable PKs, which are rigid insulating materials, to be used as dielectric materials, broadening their range of applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 887–892 相似文献
53.
Positivity - We introduce mixed Morrey spaces and show some basic properties. These properties extend the classical ones. We investigate the boundedness in these spaces of the iterated maximal... 相似文献
54.
Toru Sasahara 《Journal of Geometry and Physics》2010,60(6-8):884-895
We classify biminimal Lagrangian surfaces in complex space forms under the condition that the integral curves of Maslov vector field are geodesics. 相似文献
55.
Toru Minami Ryoji Kouno Tatsuo Okauchi Mitsuharu Nakamura Junji Ichikawa 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):689-692
The α-phosphonovinyl anions, generated in situ from treatment of β-hetero-substituted vinyl-phosphonates 1a-c with LDA (or LTMP), were trapped with various electrophiles such as chlorotriorganosilanes, chlorotrimethylgermane, chlorotriorganotins, dimethyl disulfide, and halogen to afford the corresponding β-hetero-substituted α-functionalized vinylphosphonates 2–14 in good to excellent yields. The Friedel-Crafts reaction of α-(silyl) or α-(germyl)phosphonoketene dithioacetals 2, 9 or 4 with acid chlorides gave α-acylated phosphonoketene dithioacetals 15–19 in 53–91 % yields. The palladium-catalyzed cross-coupling reaction of β-ethoxy-α-(tributylstannyl)vinylphosphonate 13 with a variety of organic halides (R = acyl, allyl, aryl etc.) provided β-ethoxy-α-substituted vinylphosphonates 20–25 in good to moderate yields. The palladium-mediated cross-coupling reaction of α-(iodo)-vinyl-phosphonates 7, 14 with terminal acetylenes afforded α-alkynylated vinylphosphonates 26–29 in 69–83 % yields. 相似文献
56.
Takahiro Egawa Kazuhisa Hirabayashi Dr. Yuichiro Koide Chiaki Kobayashi Dr. Naoya Takahashi Dr. Tomoko Mineno Dr. Takuya Terai Dr. Tasuku Ueno Dr. Toru Komatsu Dr. Yuji Ikegaya Prof. Norio Matsuki Prof. Tetsuo Nagano Dr. Kenjiro Hanaoka 《Angewandte Chemie (International ed. in English)》2013,52(14):3874-3877
57.
Naoyuki Masuda Osamu Yamamoto Masahiro Fujii Tetsuro Ohgami Ayako Moritomo Toru Kontani 《合成通讯》2013,43(17):2305-2316
Various N‐3‐alkylated thiazolidenesulfonamide derivatives were efficiently prepared by the direct endo‐selective alkylation of thiazolylsulfonamides. The effects of different bases and solvents were investigated, and the NaH–THF combination was found to be the most effective at conferring high yields and endo‐selectivity. 相似文献
58.
UV rays in sunlight are an important factor in the degradation of chemicals. In this study, we investigated the degradation of nonionic surfactants, nonylphenol polyethoxylates (NPEOs) with 10 or 70 ethylene oxide (EO) units using UVA, B and C, and their genotoxic change based on phosphorylation of histone H2AX (γ‐H2AX), a marker of DNA damage. NPEOs were degraded dependent on the energy of UV, that is, UVC having the highest energy was most effective, whereas UVA having the lowest energy caused little change. The EO side chain of NPEO(70) was broken near the benzene ring by UV, producing NPEOs with a shortened EO chain (around 10 units). The generation of γ‐H2AX reflected the pattern of degradation; shortening of the EO chain changed NPEO(70) into an inducer for γ‐H2AX, and degradation of NPEO(10) attenuated the genotoxicity. The γ‐H2AX generated by NPEO(10) and UV‐degraded NPEO(70) was independent of the cell cycle. The formation of DNA double strand breaks detected by gel electrophoresis was consistent with the results for γ‐H2AX. These results suggested that UV rays can make NPEOs harmless or genotoxic according to the degradation of the EO side chain, the effects being dependent on wavelength. 相似文献
59.
Hemin was physically adsorbed onto porous carbon felt (CF), a microelectrode ensemble of micro-carbon fiber (ca. 7 μm in diameter) and possessing a three-dimensional random structure. The hemin-CF exhibited a well-defined redox wave that is due to Fe(III)/Fe(II) redox process in hemin, with a formal potential of ?0.32 V (vs. Ag/AgCl) in deoxygenated buffer solution of pH 7.0. The surface coverage of the electroactive hemin molecules on the surface of the CF was calculated to be 5.0?×?10?11 mol cm?2, and the apparent heterogeneous electron transfer rate constant is 3.35 s?1. The hemin-CF electrode displays excellent electrocatalytic activity for the reduction of dissolved oxygen (DO), and the magnitude of the cathodic current increases with increasing concentrations of DO in the sample solution. The electrode was used as a flow-through detector for sensitive and rapid consecutive determination of DO. Deoxygenated pH 7.0 solutions were analyzed at a flow rate of 8.0 mL min?1 at an applied potential of ?0.2 V, and highly reproducible cathodic peak current responses to DO were observed in the 0.72 to 13.3 mg L?1 concentration range. The maximum throughput is 170 samples h?1. The hemin-CF-based amperometric flow-sensor was applied to determine the concentration of DO in environmental water samples. Graphical abstract
Hemin was physically adsorbed onto porous carbon felt (CF), a microelectrode ensemble of micro-carbon fiber (ca. 7 μm in diameter). The hemin-CF electrode was used as a flow-through detector for highly sensitive and rapid determination of dissolved oxygen. 相似文献
60.
A three-step synthesis of (R)-7-hydroxycarvone (1), which is anticipated to be a valuable building block for the versatile preparation of natural products, is described. Optimization of the reaction conditions for photooxygenation and migration of (S)-α-pinene 2, tetrapropylammonium perruthenate (TPAP) oxidation of the generated alcohol, and a subsequent ring-opening reaction in the presence of Cu(OTf)2 led to the synthesis of 1 with good reproducibility. The desired product 1 was thus obtained in 46% yield over three steps. 相似文献