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991.
Sumino Y Kitahata H Shinohara Y Yamada NL Seto H 《Langmuir : the ACS journal of surfaces and colloids》2012,28(7):3378-3384
The motion of an oil-water interface that mimics biological motility was investigated in a Hele-Shaw-like cell where elastic surfactant aggregates were formed at the oil-water interface. With the interfacial motion, millimeter-scale pillar structures composed of the aggregates were formed. The pillars grew downward in the aqueous phase, and the separations between pillars were roughly equal. Small-angle X-ray scattering using a microbeam X-ray revealed that these aggregates had nanometer-scale lamellar structures whose orientation correlated well with their location in the pillar structure. It is suggested that these hierarchical spatial structures are tailored by the spontaneous interfacial motion. 相似文献
992.
Ke Wu Zhenzi Jing LiLi Pan Lei Zhou Emile Hideki. Ishida 《Research on Chemical Intermediates》2012,38(7):1637-1646
Diatomaceous earth (DE) solidifies hydrothermally with analcime formation. With analcime formation, strength development was much greater than that with calcium silicate hydrate (CSH) formation. NaOH addition conditioned analcime formation because NaOH solution not only promoted dissolution of quartz and montmorillonite but also provided Na+ to form the analcime. Curing temperature and time affected analcime formation, and, in this study, over 6 h (at 200 °C) and 175 °C (for 12 h), analcime seemed to form readily. After hydrothermal treatment, the skeletons of diatoms can still be seen in the solid after analcime formation but can hardly be found after CSH formation. 相似文献
993.
Prof. Dr. Tohru Wada Dr. Hideki Ohtsu Prof. Dr. Koji Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(8):2374-2381
A bis(ruthenium–bipyridine) complex bridged by 1,8‐bis(2,2′:6′,2′′‐terpyrid‐4′‐yl)anthracene (btpyan), [Ru2(μ‐Cl)(bpy)2(btpyan)](BF4)3 ([ 1 ](BF4)3; bpy=2,2′‐bipyridine), was prepared. The cyclic voltammogram of [ 1 ](BF4)3 in water at pH 1.0 displayed two reversible [RuII,RuII]3+/[RuII,RuIII]4+ and [RuII,RuIII]4+/[RuIII,RuIII]5+ redox couples at E1/2(1)=+0.61 and E1/2(2)=+0.80 V (vs. Ag/AgCl), respectively, and an irreversible anodic peak at around E=+1.2 V followed by a strong anodic currents as a result of the oxidation of water. The controlled potential electrolysis of [ 1 ]3+ ions at E=+1.60 V in water at pH 2.6 (buffered with H3PO4/NaH2PO4) catalytically evolved dioxygen. Immediately after the electrolysis of the [ 1 ]3+ ion in H216O at E=+1.40 V, the resultant solution displayed two resonance Raman bands at $\tilde \nu $ =442 and 824 cm‐1. These bands shifted to $\tilde \nu $ =426 and 780 cm?1, respectively, when the same electrolysis was conducted in H218O. The chemical oxidation of the [ 1 ]3+ ion by using a CeIV species in H216O and H218O also exhibited the same resonance Raman spectra. The observed isotope frequency shifts (Δ$\tilde \nu $ =16 and 44 cm?1) fully fit the calculated ones based on the Ru? O and O? O stretching modes, respectively. The first successful identification of the metal? O? O? metal stretching band in the oxidation of water indicates that the oxygen–oxygen bond at the stage prior to the evolution of O2 is formed through the intramolecular coupling of two Ru–oxo groups derived from the [ 1 ]3+ ion. 相似文献
994.
The ordering and antiphase boundary (APB)-like fault found in the α″-martensite of β-Ti shape memory alloys are studied. Long-range chemical ordering was not found, but APB-like faults were observed in every martensite plate studied by transmission electron microscopy. These faults have morphology similar to the APBs observed in ordered phases. The superlattice reflections observed in some previous works were a consequence of multiple diffractions. APB-like faults were not observed in the parent phase, leading to the conclusion that the faults were introduced by the martensite transformation. The fault took the form of a wavy tube running perpendicular to the habit plane. The fault was a ‘transformation-induced APB’ with an additional small displacement due to the pre-existing athermal ω phase. The displacement vector was determined to be [–3/50, ?23/50, 1/2]. Geometrical aspects of the formation of APB-like faults are also discussed. 相似文献
995.
Shuji?WakaikiEmail author Hideki?Ichida Toshiki?Kawase Kohji?Mizoguchi DaeGwi?Kim Masaaki?Nakayama Yasuo?Kanematsu 《The European Physical Journal B - Condensed Matter and Complex Systems》2013,86(9):387
We have investigated the photoluminescence (PL) dynamics of ZnO thin films under intense excitation conditions using an optical-Kerr-gating method. The PL bands originating from exciton-exciton scattering (P emission) and biexciton (M emission) have been observed at 10 K. The ultrashort gating time of 0.6 ps has enabled us to obtain precise information of the temporal profiles of the peak energies and the intensities of the P- and M-PL bands. We have found that the decay time of the P emission becomes longer with increasing film thickness, while that of the M emission is independent of the film thickness. Although the decay time of the P emission is an increasing function of the film thickness, the relation is not in proportion, which is contrary to the predicted proportionality based on a simple model of photon-like polariton propagation. 相似文献
996.
Masashi Kijima Kenichi Setoh Hideki Shirakawa 《Molecular Crystals and Liquid Crystals》2013,570(1):911-918
Abstract A novel liquid crystalline N-substituted pyrrole having an ionic viologen side chain was synthesized, and was polymerized by a FeCl3 method. Thermotropic liquid crystalline behavior of the pyrrole and the polymerized material were investigated by DSC, thermo-controlled polarizing optical microscopy, and XRD. The pyrrole derivatives showed two smectic phases between isotropic and crystalline (solid) phases. Viologen functions of redox and cation-radical generation for the pyrrole derivatives were confirmed by cyclic voltammetry with UV-Vis spectroscopy. 相似文献
997.
Hideki Tanaka Jun Onoe Toshiki Kara Aiko Nakao Kazuo Takeuchi 《Molecular Crystals and Liquid Crystals》2013,570(1):701-705
Abstract The interaction between C60 and Si atoms was investigated using X-ray photoelectron spec-troscopy (XPS) for the photo-irradiated Si-deposited C60 film in order to establish a method of a synthesis for the Si-coated C60. It was found that the Cls spectrum of the photo-irradiated film contains a peak due to C-Si bonding, while no peak due to C-Si bonding was observed for the film before photo-irradiation. This indicates that Si atoms stick to C60 when using the present method. 相似文献
998.
To monitor protein-glycoprotein interactions on magnetic beads, the present study developed an electrochemical assay of the binding between concanavalin A (ConA) and ovalbumin (OVA). The system was a powerful model that could be used to evaluate cell junctions. ConA with an electroactive daunomycin was immobilized on 6 different sizes of magnetic beads (diameter: 1.0-8.9 μm) through a cross-linking agent. Six sizes of OVA-beads (diameter: 1.0-8.9 μm) were also prepared using a similar method. The binding was evaluated using an oxidation peak of ConA with daunomycin because ConA recognized OVA with α-mannose residues. When binding took place on the beads' surface, the peak current was decreased due to the electroactive moieties being covered with OVA. When ConA/daunomycin-OVA binding was evaluated, the change of the peak current obtained by the beads (diameter: 8.9 μm) modified with ConA and daunomycin was the greatest in the presence of OVA-modified beads (diameter: 2.5 μm). In contrast, particle agglomeration was observed for the smallest beads (diameter: 1.0 μm) with ConA/daunomycin and OVA. The results suggested that ConA-OVA binding depended on the size of beads. Thus, this method could be applied to measure protein-glycoprotein interactions on the cell surface. 相似文献
999.
Hirotsu M Shimizu Y Kuwamura N Tanaka R Kinoshita I Takada R Teki Y Hashimoto H 《Inorganic chemistry》2012,51(2):766-768
The reaction of manganese(II) acetate with a xanthene-bridged bis[3-(salicylideneamino)-1-propanol] ligand, H(4)L, afforded the tetramanganese(II,II,III,III) complex [Mn(4)(L)(2)(μ-OAc)(2)], which has an incomplete double-cubane structure. The corresponding reaction using manganese(II) chloride in the presence of a base gave the tetramanganese(III,III,III,III) complex [Mn(4)(L)(2)Cl(3)(μ(4)-Cl)(OH(2))], in which four Mn ions are bridged by a Cl(-) ion. A pair of L ligands has a propensity to incorporate four Mn ions, the arrangement and oxidation states of which are dependent on the coexistent anions. 相似文献
1000.
Sakai H Aikawa S Matsuda W Ohmori T Fukukita Y Tezuka Y Matsumura A Torigoe K Tsuchiya K Arimitsu K Sakamoto K Sakai K Abe M 《Journal of colloid and interface science》2012,376(1):160-164
We have developed a novel cinnamic acid-type photo-cleavable surfactant. This surfactant experiences photo-cleavage through UV-induced cyclization in aqueous solutions. The photo-cleavage not only reduces its capabilities as a surfactant but also yields two functional materials including a coumarin derivative and an aminated polyoxyethylene compound. This means that the photo-cleavable surfactant synthesized in this study is a photo-responsive function-exchangeable material. In our current study, we have characterized the photo-cleavable behavior that occurs in aqueous solutions and a resulting change in interfacial properties. The photo-cleavage induces an increased interfacial tension of a squalane/water interface and a decreased solubilization capability of the surfactant micelles. 相似文献