論文 - 山本 雅博
-
A revisit to the non-Bornian theory of the Gibbs energy of ion transfer between two immiscible liquids 査読あり
Wataru Murakami, Kazuo Eda, Masahiro Yamamoto, Toshiyuki Osakai
Journal of Electroanalytical Chemistry 704 38 - 43 2013年9月
-
Potentiometric coulometry based on charge accumulation with a peroxidase/osmium polymer-immobilized electrode for sensitive determination of hydrogen peroxide 査読あり
Chi-Hua Nieh, Yuki Kitazumi, Osamu Shirai, Masahiro Yamamoto, Kenji Kano
Electrochemistry Communications 33 135 - 137 2013年8月
-
Effects of polymorphic transformation on pharmaceutical properties of direct compressed tablets containing theophylline anhydrate bulk powder under high humidity 査読あり
Yuta Otsuka, Masahiro Yamamoto, Hiroyuki Abe, Makoto Otsuka
Colloids and Surfaces B: Biointerfaces 102 931 - 936 2013年2月
共著
The effect of high humidity on the pharmaceutical properties of direct compression tablets containing theophylline anhydrate (TA) was investigated to prepare high quality pharmaceuticals. A mixed powder (230. mg) containing the TA, β-lactose anhydrate, microcrystalline cellulose (MCC) and magnesium stearate was compressed in a die by 8-mm diameter punches with flat surfaces at 4.8. kN. The TA tablets were stored in desiccators at 96% relative humidity and 20°C. Physicochemical properties of the tablets were measured using, powder X-ray diffraction (XRD), X-ray computed tomography (XCT), the tablet hardness test and the dissolution test. The water absorption process could be divided into two stages: 1.0% absorption at for 0-6. h due to absorption of MCC, and 4% absorption at 6-24. h due to hydration of TA. The XRD and XCT results were supported be tablet weight changes in the initial and later stages, respectively. The relationship between tablet hardness and water absorption indicated that the first stage of absorption was more significant. In contrast, the relationship between the dissolved amount at 20. min (D20) and water absorption indicated that the first stage was less effective. The first stage of absorption was due to MCC, but the second was due to hydration of the TA bulk powder. © 2012 Elsevier B.V.
-
Numerical simulation of diffuse double layer around microporous electrodes based on the Poisson-Boltzmann equation 査読あり
Y. Kitazumi et al.
Electrochimica Acta 2013年
共著
-
Effects of polymorphic transformation on pharmaceutical properties of direct compressed tablets containing theophylline anhydrate bulk powder under high humidity 査読あり
Y. Otsuka et al.
Colloids and Surfaces B: Biointerfaces 2013年
共著
-
Diffusion-controlled Detection of Glucose with Microelectrodes in Mediated Bioelectrocatalytic Oxidation 査読あり
T. Noda et al.
Anal. Sci. 2013年
共著
-
Potentiometric coulometry based on charge accumulation with a peroxidase/osmium polymer-immobilized electrode for sensitive determination of hydrogen peroxide 査読あり
Chi-Hua Nieh et al.
Electrochem. Comm. 2013年
共著
-
A revisit to the non-Bornian theory of the Gibbs energy of ion transfer between two immiscible liquids 査読あり
T. Osakai et al.
J. Electroanal. Chem. 2013年
共著
-
Tatsuo NODA, Mizue WANIBUCHI, Yuki KITAZUMI, Seiya TSUJIMURA, Osamu SHIRAI, Masahiro YAMAMOTO, Kenji KANO
Analytical Sciences 29 ( 3 ) 279 - 281 2013年
-
Numerical simulation of diffuse double layer around microporous electrodes based on the Poisson-Boltzmann equation
Yuki Kitazumi, Osamu Shirai, Masahiro Yamamoto, Kenji Kano
Electrochimica Acta 112 171 - 175 2013年
共著
The structure of the diffuse double layer around a nm-sized micropore on porous electrodes has been studied by numerical simulation using the Poisson-Boltzmann equation. The double layer capacitance of the microporous electrode strongly depends on the electrode potential, the electrolyte concentration, and the size of the micropore. The potential and the electrolyte concentration dependence of the capacitance is different from that of the planner electrode based on the Gouy's theory. The overlapping of the diffuse double layer becomes conspicuous in the micropore. The overlapped diffuse double layer provides the mild electric field. The intensified electric field exists at the rim of the orifice of the micropore because of the expansion of the diffuse double layers. The characteristic features of microporous electrodes are caused by the heterogeneity of the electric field around the micropores. © 2013 Elsevier Ltd. All rights reserved.
-
Particle Stabilization of Oil-in-Water-in-Air Materials: Powdered Emulsions 査読あり
Ryo Murakami, Hiroshi Moriyama, Masahiro Yamamoto, Bernard P. Binks, Anaïs Rocher
Advanced Materials 24 ( 6 ) 767 - 771 2012年2月
-
“Particle stabi- lization of oil-in-water-in-air materials: powdered emulsions” 査読あり
Murakami, R.; Moriyama, H.; Yamamoto, M.; Binks, B. P.; Rocher, A.
Advanced Materials 24 767 - 771 2012年
共著
-
電気化学分析（分析化学実技シリーズ，機器分析編・１２） 木原壯林・加納健司著 共立出版 2012年8月15日発行
山本 雅博
Review of Polarography 58 ( 2 ) 103 - 104 2012年
-
“Phase-Separation of Ordered D03 Precipitates in A2 + D03 Two-Phase Microstructure of Fe-Si-V Ternary Alloy System ” 査読あり
K. Ota, T. Shinoda, T. Hayashi, T. Kozakai, M. Doi, M. Yamamoto, M. Takagi, A. Matsumuro,
Processing and Fabrication of Advanced Materials XVIII 18 12 - 14 2009年
共著
-
Lattice widening in niobium-doped TiO<inf>2</inf> nanotubes: Efficient ion intercalation and swift electrochromic contrast 査読あり
Andrei Ghicov, Masahiro Yamamoto, Patrik Schmuki
Angewandte Chemie - International Edition 47 ( 41 ) 7934 - 7937 2008年9月
共著
Widely accommodating: Novel TiO2/Nb nanotube layers (see picture, right) are grown on a titanium-niobium alloy. Niobium doping of TiO2 enlarges the cell parameters of the anatase lattice (left; Nb green, Ti gray, O red), facilitating the intercalation of H+ and Li+ ions, and even larger Na+ ions (blue) into the lattice. (Figure Presented) © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.
-
Artificially phase-separated binary self-assembled monolayers composed of 11-amino-1-undecanethiolate and 10-carboxy-1-decanethiolate on Au(1 1 1): A comparative study of two preparing methods 査読あり
Pham Hong Phong, Hyroyuki Tomono, Naoya Nishi, Masahiro Yamamoto, Takashi Kakiuchi
Electrochimica Acta 53 ( 14 ) 4900 - 4906 2008年5月
共著
出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD
Two methods have been compared for preparing artificially phase-separated two-component SAMs on Au(1 1 1) composed of 11-amino-1-undecanethiolates (AUTe) and 10-carboxyl-1-decanethiolates (CDTe), which would form, thermodynamically, a homogeneously mixed binary SAMs. The first method starts with the formation of a phase-separated binary SAM of AUTe and 2-hydroxy-1-ethanethiolate (HETe) as a template of the artificially phase-separated SAM, followed by the selective desorption of HETe domains and succeeding filling of the vacancy with CDTe. The second method utilizes fluoren-9-ylmethyl N-(11-mercaptoundecyl) carbamate (FMUCe) instead of 11-amino-1-undecanethiol in preparing the template. After the filling with CDTe, the 9-fluorenylmethyloxycarbonyl (Fmoc) group is removed to obtain AUTe domains. Both methods yield artificially phase-separated binary SAMs having AUTe domains of tens nanometer across. The molecularly flat SAM surface with nanometer-scale domains of different acid-base and electrostatic properties are thus created. For preparing binary SAMs with a higher degree of phase separation, the second method is a better choice; a more clear-cut phase separation is achieved. © 2008 Elsevier Ltd. All rights reserved.
-
Counterion binding induces attractive interactions between negatively-charged self-assembled monolayer of 3-mercaptopropionic acid on Au(111) in reductive desorption 査読あり
Yukio Kitagawa, Daisuke Hobara, Masahiro Yamamoto, Takashi Kakiuchi
Journal of Solid State Electrochemistry 12 ( 4 ) 461 - 469 2008年4月
共著
出版者・発行元：SPRINGER
The electrochemical reductive desorption of the self-assembled monolayers of 3-mercaptopropionic acid in an aqueous alkaline solution gives a sharp peak with the full width at half maximum of about 20 mV irrespective of the type of cations in a linear scan voltammogram. This suggests that a strong attractive interaction exists between negatively charged carboxylate groups in the self-assembled monolayer surface due to the counterion binding, which not only simply stabilizes the adsorbed carboxylates but also makes the interaction between the adsorbed thiolates even attractive possibly by forming a two-dimensional ionic crystal. The effect of tetraalkylammonium ions on the shape of the voltammograms was also examined. © 2007 Springer-Verlag.
-
``Lattice Widening in Niobium-Doped TiO2 Nanotubes: Efficient Ion Intercalation and Swift Electrochromic Contrast," 査読あり
Ghicov, A.; Yamamoto, M.; Schumki, P.
Angew. Chem. Int. Ed., 47 1 - 5 2008年
共著
-
``Artificially phase-separated binary self-assembled monolayers composed of 11-amino-1-undecanethiolate and 10-carboxy-1-decanethiolate on Au(111): A comparative study of two preparing methods," 査読あり
Phong, P. H.; , Tomono ,H.; Nishi, N.; Yamamoto, M. and Kakiuchi, T.
Electrochimica Acta 53 4900 - 4906 2008年
共著
-
``Counterion Binding Induces Attractive Interaction between Negatively-charged Self-assembled Monolayer of 3-Mercaptopropionic Acid on Au(111) in Reductive Desorption," 査読あり
Kitagawa, Y.; Hobara, D.; Yamamoto, M.; Kakiuchi, T.
J. Solid State Electrochem. 12 461 - 469 2008年
共著