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21.
Koichi Kikuta Koji Noda Shin Okumura Toshiaki Yamaguchi Shin-ichi Hirano 《Journal of Sol-Gel Science and Technology》2007,42(3):381-387
Orientation control of perovskite compounds was investigated by the application of a seed layer prepared from oxide nanosheets.
An aqueous suspension of oxide nanosheets was prepared by the exfoliation of a layered compound of KCa2Nb3O10 oxide grains. A seed layer composed of (TBA)Ca2Nb3O10 nanosheets (TBA = tetrabutylammonium) was formed on a glass substrate by simply dip coating it in the suspension. Two kinds
of perovskite compounds, LaNiO3 (LNO) and Pb(Zr,Ti)O3 (PZT) with a preferred orientation of (00l) were successfully grown on this seeded glass substrate. In this study, the relation between lattice mismatch and electrical
properties is investigated. A large, oriented PZT film with a size of 5 ×4 cm shows an improved P-E hysteresis behavior by
use of this orientation control. 相似文献
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Vitamin E glycosides were synthesized and enzymatic hydrolysis was examined for use as potential pro-drugs, however, the glycoside bond was found to be stable. On the other hand, among the glycosides synthesized, dl-alpha-tocopherylglucoside (6b) and dl-alpha-tocopherylmannoside (6c) showed strong inhibitory action on histamine release from mast cells. In addition, 6c also showed a suppressive action on IgE antibody formation. Thus, tocopheryl glycoside showed new properties compared to tocopherol (vitamin E). In particular, 6c was shown to be a novel lead compound with excellent manifold anti-allergic activity and anti-inflammatory activity. 相似文献
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26.
Shin-Ichi Hirano Toshinobu Yogo Ko-Ichi Kikuta Wataru Sakamoto 《Journal of Sol-Gel Science and Technology》1994,2(1-3):329-334
The sol-gel processing is one of promising methods to fabricate well-derived integrated thin films at relatively low temperature. Ferroelectric niobates films do afford the possibilities for adding the values by the hybridization with semiconductor and/or electro-optic systems. The molecular level designing of the precursor solution was stressed as well as the control of key processing factors. The advantages of this sol-gel have been extended to prepare the ferroelectric Pb(Mg, Nb)O3-PbTiO3 solid solution films integrated on Si wafers. The crystallization of the films with desired crystal structure could be promoted by the controlled partial hydrolysis of designed alkoxide solution in the intermediate state and the pre-heated treatment of alkoxide-derived films in flow of water vapor and oxygen gas mixture. 相似文献
27.
Takushi Kurihara Mariko Sugiyama Hiroshi Hirano Ken-Ichi Tomita Masayoshi Sakaki 《Journal of heterocyclic chemistry》1975,12(3):541-545
Reaction of o-nitrobenzylideneacetylacetone ( 1a ) with hydrazine dihydrochloride in methanol gave 4-(α-methoxy-o-nitrobenzyl)-3,5-dimethylpyrazole hydrochloride ( 4a ), whose structure was unambigously confirmed by an X-ray crystallographic analysis, via 4-(o-nitrobenzylidene)-3,5-dimethylisopyrazole ( 2a ). Compound 2a was synthesized by condensation of 1a with hydrazine dihydrochloride in acetonitrile. Analogously the corresponding o-chloro derivatives ( 2b, 4b ) were obtained. These were converted to N-methyl ( 6b ) and N-acetyl ( 7a,b ) derivatives and the behaviors on bromination and pyrolysis were investigated. 相似文献
28.
Separation of sodium dodecyl sulfate (SDS)-protein complexes is difficult on plastic microchips due to protein adsorption onto the wall. In this paper, we elucidated the reasons for the difficulties in separating SDS-protein complexes on plastic microchips, and we then demonstrated an effective method for separating proteins using polymethyl methacrylate (PMMA) microchips. Separation difficulties were found to be dependent on adsorption of SDS onto the hydrophobic surface of the channel, by which cathodic electroosmotic flow (EOF; reversed flow) was generated. Our developed method effectively utilized the reversed flow from this cathodic EOF as a driving force for sample proteins using permanently uncoated but dynamic SDS-coated PMMA microchips. High-speed (6 s) separation of proteins and peptides up to 116 kDa was successfully achieved using this system. 相似文献
29.
Oyamatsu D Hirano Y Kanaya N Mase Y Nishizawa M Matsue T 《Bioelectrochemistry (Amsterdam, Netherlands)》2003,60(1-2):115-121
The enzymatic activity of diaphorase (Dp) immobilized on a solid substrate was characterized using a scanning electrochemical microscope (SECM) with shear force feedback to control the substrate-probe distance. The shear force between the substrate and the probe was monitored with a tuning fork-type quartz crystal and used as the feedback control to set the microelectrode probe close to the substrate surface. The sensitivity and the contrast of the SECM image were improved in the constant distance mode (distance, 50 nm) with the shear force feedback compared to the image in the constant height mode without the feedback. By using this system, the SECM and topographic images of the immobilized diaphorase were simultaneously measured. The microelectrode tip used in this study was ground aslant like a syringe needle in order to obtain the shaper topographic images. This shape was also effective for avoiding the interference during the diffusion of the enzyme substrates. 相似文献
30.
Tomohisa?Yamaguchi Keisuke?Kimura Akira?Tsuchida Tsuneo?OkuboEmail author Mitsuhiro?Matsumoto 《Colloid and polymer science》2005,283(10):1123-1130
Macroscopic and microscopic dissipative structural patterns formed in the course of drying the fractionated and monodisperse bentonite particles (plate-like in their shape) in aqueous deionized suspension and in the presence of NaCl have been studied on a cover glass. The patterns coexisted with the broad ring of the hill accumulated with the particles and with the round hills are formed around the outside edges of the film and in the center, respectively, in the macroscopic scale. By the addition of NaCl the pattern shifts from the broad ring to the round hill in the center. The spoke-like cracks, which have been observed for the suspensions of the spherical particles so often hitherto, are not observed at all for the bentonite suspensions. The characteristic convection flow of the particles and the interactions among the particles and substrate are important for the macroscopic pattern formation. Wrinkled, branch-like and/or star-like fractal patterns are observed in the microscopic scale. These patterns are determined mainly by the electrostatic and polar interactions between the particles and/or between the particle and the substrate in the course of drying. 相似文献