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191.
K. Kato K. Tanaka S. Kayukawa K. Suzuki Y. Masuda T. Kimura K. Nishizawa T. Miki 《Applied Physics A: Materials Science & Processing》2007,88(2):273-276
CaBi4Ti4O15 (CBTi144) micro-plateaus were fabricated on Si wafers and Pt foils using a self-assembled monolayer (SAM) and a complex metal
alkoxide solution. The micro-plateaus are delineated by metal masks, which are used for shadowing against the ultraviolet
(UV) irradiation for decomposition of SAM to make the surface hydrophilic. The micro-plateaus crystallized to a ferroelectric
phase with random orientation. The crystallization depended on the SAM-derived ultra thin layers at the surface of the substrates.
The primitive PFM measurements without any top electrodes confirmed that the micro-plateaus exhibited the piezoresponse behaviors.
The piezoelectric constant, d33, had some distribution, and the maximum d33 was confirmed as about 45 pm/V, which is identical to the d33 of the polar-axis oriented CBTi144 thin films.
PACS 77.84.-s; 81.20.Fw; 77.65.-j 相似文献
192.
Kimura Kyoko 《偏微分方程通讯》2013,38(12):1335-1361
193.
194.
Toshimitsu Ichimori Shinichi Yamazaki Kunio Kimura 《Journal of polymer science. Part A, Polymer chemistry》2011,49(21):4613-4617
The influence of shear flow, especially the timing for the application of shearing, was examined to enhance the selectivity for the preparation of poly(p‐oxybenzoyl) (Pp‐OB) by using hydrodynamically induced phase separation during polymerization of 4‐(4‐acetoxybenzoyloxy)benzoic acid (p‐ABAD) and m‐acetoxybenzoic acid (m‐ABA). The polymers containing few m‐oxybenzoyl (m‐OB) moieties were obtained as precipitates even at high content of m‐OB moiety in feed (χf) under shear flow. The content of m‐OB moiety in the precipitates (χp) prepared under shearing throughout the polymerization at the shear rate (γ) of 489 s?1 was 6.3 mol % even at χf of 60 mol %. Especially, the Pp‐OB was obtained as the precipitates at χf of less than 50 mol %. The timing of the application of the shearing influenced the selectivity significantly, and the shearing just after the precipitation of the oligomers started was quite efficient to enhance the selectivity more. The χp of the precipitates prepared with shearing at γ of 489 s?1 just after the precipitation was only 3.9 mol % even at χf of 60 mol %. The shear flow reduced the difference in the reactivity between p‐ABAD and m‐ABA, resulting in the decrease in the selectivity with regard to the formation of p‐oxybenzoyl homo‐oligomer. However, the shear flow enhanced the difference in the miscibility between homo‐oligomers and co‐oligomers. This change in the miscibility by shear flow brought about the more rapid precipitation of homo‐oligomers, leading to the enhancement of the selectivity. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
195.
Masahiro Kihara Shin‐Ichiro Kohama Shota Umezono Kanji Wakabayashi Shinichi Yamazaki Kunio Kimura 《Journal of polymer science. Part A, Polymer chemistry》2011,49(5):1088-1096
Poly(p‐oxybenzoyl) (POB) crystals were prepared by reaction‐induced crystallization during direct polymerization of p‐hydroxybenzoic acid in the presence of boronic anhydrides. Polymerizations were carried out at 300 °C in dibenzyltoluene at a concentration of 1% with three kinds of anhydrides of boronic acid such as 3,4,5‐trifluorophenylboronic acid (TFB), 4‐methoxyphenylboronic acid (MPB) and 4‐biphenylboronic acid (BPB). The POB crystals were formed as precipitates in the solution and the morphology was considerably influenced by both the structure of the boronic anhydride and its concentration (cB). Needle‐like crystals were firmed in the presence of TFB anhydride (TFBA) at cBs of 5 and 10 mol % by the spiral growth of lamellae. Spherical aggregates of slab‐like crystals were formed at cBs from 50 to 100 mol %. The polymerization with MPB anhydride and BPB anhydride (BPBA) also yielded the needle‐like crystals at cBs of 50 and 5 mol %, respectively. The polymerization with TFBA at lower cB was favorable to prepare the needle‐like crystal. Molecular weight was also influenced by the structure of the boronic anhydride and cB. Mn increased generally with cB and BPBA gave the highest Mn of 14.7 × 103 at cB of 100 mol %. The loose packing of the molecules in the crystal caused by the bulkiness of the end‐groups made the polymerization in the crystals more efficiently. Morphology and molecular weight of the POB crystals could be controlled by the chemical structure and the content of boronic anhydride. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011. 相似文献
196.
197.
We report the synthesis of block and alternating thiophene/phenylene co‐oligomers that is based either on the Suzuki coupling reaction or on the Grignard reaction. These reaction schemes enable us to obtain the target compounds at reasonably high yields. The resulting materials have been fully characterized through the solid‐state 13C nmr and Fourier‐transform ir as well as the 1H nmr. Of these, the solid‐state 13C nmr and ir are particularly useful in characterizing the materials of higher molecular weight, since those materials are difficult to dissolve in organic solvents. 相似文献
198.
T. Kawahara M. Miyazaki A. Kimura Y. Okamoto J. Morimoto T. Miyakawa 《Applied Physics A: Materials Science & Processing》1999,69(3):343-346
The noncontact imaging of the buried structures is carried out in the open-air atmosphere by using the photothermal deflection
(PTD) method. We applied these techniques to the layered samples. Besides the PTD images for the optically opaque buried structures,
the parameters of the materials such as thermal diffusivity can also be calculated from the PTD amplitude and phase signal
in the PTD scanning images. When the PTD signals at two different modulation frequencies are used, the thermal diffusivity
of the buried structure can be obtained from the PTD signal outside of the sample nondestructively.
Received: 27 November 1998 / Accepted: 18 March 1999 / Published online: 7 July 1999 相似文献
199.
Takayoshi Kimura Sekai Iwama Satoko Kido Mohammad Abdullah Khan 《The Journal of chemical thermodynamics》2009,41(10):1170-1177
Enthalpies of mixing and the densities of ethanol solution of R- and S-enantiomers of camphor, 10-camphorsulfonamide, 10-camphorsulfonic acid, camphorquinone, and 10-camphorsulfonyl chloride have been measured for a wide range of mole fractions of heterochiral components at 298.15 K. Enthalpies of mixing were exothermic for all concentrations and heterochiral solutions were more stable than each of the homochiral solutions. Enthalpic stabilization of mixing of heterochiral solutions was increased with a decreasing concentration of all the camphor derivatives measured. The sequence of enthalpic stabilization on mixing was 10-camphorsulfonyl chloride, 10-camphorsulfonic acid, 10-camphorsulfonamide, camphor, and camphorquinone. Apparent molar volumes were determined and excess volumes of mixing of heterochiral solutions were small and negative. Enthalpic stabilizations were found to be dependent on dipole–dipole interaction between solutes and solvents. 相似文献
200.