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191.
Ken‐ichi Itoh Takamitsu Utsukihara Kenji Funayama Hiroshi Sakamaki Miyuki Kanamori T. Tomoyoshi Takahashi Yoshikazu Saitoh Masatoshi Matsushita Liangyou He Chikao Hashimoto Takashi Sugiyama C. Akira Horiuchi 《应用有机金属化学》2007,21(12):1029-1032
The reaction of α,β‐unsaturated ketones with cerium (IV) sulfate tetrahydrate [Ce(SO4)2·4H2O, CS] in acetic acid gave the corresponding β‐acetoxy ketones. In the case of 2‐cyclohexen‐1‐one with CS in acetic acid, benzobicyclo[2.2.2]octen‐2‐one was obtained. The reaction mechanism also was proposed. Moreover, we report the aromatization and esterification of (R)‐(?)‐carvone by CS in acetic acid. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
192.
Here we report the first photochromism of a newly designed [2.2]paracyclophane-bridged imidazole dimer in water. The photochromic dye with a hydrophilic and a hydrophobic substituent forms vesicles in water and shows instantaneous colouration upon UV light irradiation and successive rapid fading in the dark. 相似文献
193.
Shimura K Kawai H Yoshida T Yoshida H 《Chemical communications (Cambridge, England)》2011,47(31):8958-8960
Photodeposition of a Rh cocatalyst under atmospheric conditions could simultaneously provide both Rh metal and oxide nanoparticles on a K(2)Ti(6)O(13) photocatalyst, both of which cooperatively promoted the photocatalytic hydrogen production from water and methane. 相似文献
194.
Katsuya Ishizaki 《Aequationes Mathematicae》2011,81(1-2):185-198
In this paper, we treat difference Riccati equations and second order linear difference equations in the complex plane. We give surveys of basic properties of these equations which are analogues in the differential case. We are concerned with the growth and value distributions of transcendental meromorphic solutions of these equations. Some examples are given. 相似文献
195.
In our earlier papers we constructed examples of 2-dimensional nonaspherical simply-connected cell-like Peano continua, called
Snake space. In the sequel we introduced the functor SC(−,−) defined on the category of all spaces with base points and continuous mappings. For the circle S
1, the space SC(S1, *){SC(S^1, {_{*}})} is a Snake space. In the present paper we study the higher-dimensional homology and homotopy properties of the spaces SC(Z, *){SC(Z, {_{*}})} for any path-connected compact spaces Z. 相似文献
196.
A reflection-type wavelength selective IR emitter is proposed. Surface plasmon polaritons (SPPs), which occur on metallic grating at a wavelength near the pitch of the structure, are used for controlling thermal emissions. An emission peak at a wavelength nearly equal to the period of the grating is observed. As for the other wavelength, which cannot couple with the SPPs, the IR power is confined by the reflectors including the grating. The emitter temperature increases, consuming lower input power with higher power efficiency. 相似文献
197.
Mesoporous silica (MPS) materials with different pore diameters were synthesized by a sol–gel method where organic templates such as cationic surfactant (cetyltrimethylammonium bromide) and triblock co-polymer of (poly(ethylene glycol)–poly(propylene glycol)–poly(ethylene glycol) (Pluronic P123, EO20PO70EO20)), were used. MPS surface was organo-functionalized using a silane coupling reagent (ethyl-, phenyl-, or 3-mercaptpropyltriethoxysilane). Dual-enzyme, cholesterol esterase (10.0 nm × 5.4 nm × 11.0 nm) and cholesterol oxidase (6.8 nm × 8.5 nm × 8.8 nm), was immobilized on MPS materials by physical adsorption. Amount of dual-enzyme immobilized on all MPS materials, having a different pore size (2.7, 6.4, 12.4, 14.7, and 22.6 nm), and organo-functionalized MPS was similar (CE: 1.5 mg/mg silica and CO: 0.01 mg/mg silica). High activity of dual-enzyme was obtained by adjacently immobilizing on MPS materials. Its activity on MPS-2 (pore diameter: 6.4 nm) or MPS-5 (pore diameter: 22.6 nm) showed approximately 60% of native activity. Moreover, dual-enzyme immobilized on MPS with highly hydrophobic organo-functional groups (phenyl- or mercaptopropyl-group) exhibited higher activity than that on no-substituted MPS. Relative activity of dual-enzyme immobilized on organo-functionalized MPS-2 increased from 58% to 93%, under the optimum conditions. 相似文献
198.
Simplified method to prepare atomically-ordered TiO2(1 1 0)-(1 × 1) surfaces with steps and terraces
Ryota Shimizu Katsuya IwayaTakeo Ohsawa Tetsuya HasegawaTomihiro Hashizume Taro Hitosugi 《Applied Surface Science》2011,257(11):4867-4869
An effective way to prepare atomically-ordered rutile TiO2(1 1 0) surfaces that have distinct step and terrace structures suitable for oxide thin film deposition is demonstrated. Only a two-step procedure, consisting of 20% HF etching and UHV-annealing at 1100 °C, was required to yield a clean (1 × 1) structure with step and terrace structures. Investigation of the surface using scanning tunneling microscopy, low-energy electron diffraction, and Auger electron spectroscopy reveals that carbon contamination is removed at around 800 °C, and straight steps with clear terraces appear at around 1000 °C. 相似文献
199.
Kuno T Nonoyama T Hirao K Kato K 《Langmuir : the ACS journal of surfaces and colloids》2011,27(21):13154-13158
The catalytic effect of various sequential peptides for silica biomineralization has been studied. In peptide sequence design, lysine (K) and histidine (H) were selected as the standard amino acids and aspartic acid (D) was selected to promote the charge relay effects, such as in the enzyme active site. Therefore, homopolypeptides (K(10) and H(10)), block polypeptides (K(5)D(5) and H(5)D(5)), and alternate polypeptides [(KD)(5) and (HD)(5)] were designed, and the dehydration reaction ability of trimethylethoxysilane was investigated as a quantitative model of silica mineralization. The catalytic activity per basic residue of alternate polypeptide was the highest because of the charge relay effects at the surface of the peptide. In silica mineralization using tetraethoxysilane, spherical silica particles were obtained, and their size is related to the catalytic activities of the peptides in the model systems. From these results, the effect of the functional group combination by the peptide sequence design enables the control of the efficiency of mineralization and preparation of specific inorganic materials. 相似文献
200.
Nonoyama T Kinoshita T Higuchi M Nagata K Tanaka M Sato K Kato K 《Langmuir : the ACS journal of surfaces and colloids》2011,27(11):7077-7083
We studied the effect of surface-functional-group position on precipitate morphology in the earliest stage of calcium phosphate biomineralization and determined the detailed mechanism of precipitation starting from nucleation to precipitate growth. The biomineralization template was a β-sheet peptide scaffold prepared by adsorption with carboxyl groups arranged at strict 7 ? intervals. Phosphate was then introduced. Within 10 s, highly ordered embryos of calcium phosphate were formed and confined by a peptide nanofiber pattern. They repeatedly nucleated and dissolved, with the larger embryos absorbing the smaller ones in a clear demonstration of an Ostwald-ripening-like phenomenon, then aggregated in a line pattern, and finally formed highly ordered nanofibers of amorphous calcium phosphate. This multistep growth process constitutes the earliest stage of biomineralization. 相似文献