Current Affiliation Organization 【 display / non-display 】

Current Affiliation Organization 【 display / non-display 】

University 【 display / non-display 】

University 【 display / non-display 】

Graduate School 【 display / non-display 】

Graduate School 【 display / non-display 】

External Career 【 display / non-display 】

External Career 【 display / non-display 】

Affiliated academic organizations 【 display / non-display 】

Affiliated academic organizations 【 display / non-display 】

Research Interests 【 display / non-display 】

Research Interests 【 display / non-display 】

Thesis 【 display / non-display 】

Thesis 【 display / non-display 】

• SmFeO₃-Sm₂O₃系触媒のVOC酸化活性とセンサ特性

  2015.03

• 土壌中における炭素鋼の腐食機構に及ぼす水分量の影響

  2023.09

Published Papers 【 display / non-display 】

Published Papers 【 display / non-display 】

• Effect of Diffusion Rate of Oxygen on Soil Corrosion and Evaluation of that in Soil

  Fujihashi Kenta, Nakagami Ryosuke, Oshikawa Wataru

  Zairyo-to-Kankyo ( Japan Society of Corrosion Engineering )  73 ( 8 ) 200 - 209   2024.08 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

• Color Tone of Corrosion Products and Estimation of Rust Composition by Image Processing

  Fujihashi Kenta, Oshikawa Wataru

  Tetsu-to-Hagane ( The Iron and Steel Institute of Japan )  advpub ( 0 )   2024

  Type of publication: Research paper (scientific journal)

  　View Summary

  <p>Appropriate maintenance and maintenance of infrastructures that has been used for a long time is required because there is the concern that safety will deteriorate due to atmospheric corrosion. However, the cost of maintenance and management is also increasing, and there is required to save labor and improve efficiency of maintenance and management. Therefore, the purpose of this study was to easily estimate the rust composition by the image processing of image of steel surface corroded by the outdoor exposure test. The outdoor exposure test was conducted in Choshi City and those conditions were open exposure and shelter exposure for 2.5 years. The compositions of those corrosion products measured by X-ray diffraction. Exposed test pieces were photographed RAW with the digital camera. Those photographs were developed and trimmed. The obtained images were converted from RGB images to La*b* and LCh images. The histograms of hue were fitted to the Gaussian function to determine the peak position and the spread of the histogram. As a result, it was indicated that the peak position shown in the histogram of hue shifted to the low-angle side due to the increase in FeFe₂O₄. In addition, it was indicated that the composition ratio of α-FeOOH, β-FeOOH, γ-FeOOH and FeFe₂O₄ can be estimated by the shape, spread and peak position of the histogram of hue. As shown in the graphical abstract, the composition ratio of the corrosion products measured by RIR method and estimated by image processing was in good agreement.</p>

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• Effect of Soil Particle Diameter on Soil Corrosion

  Fujihashi Kenta, Nakagami Ryosuke, Oshikawa Wataru

  Zairyo-to-Kankyo ( Japan Society of Corrosion Engineering )  72 ( 1 ) 22 - 30   2023.01

  Type of publication: Research paper (scientific journal)

  　View Summary

  <p>The main foundation structure of photovoltaic power generation facilities is a steel pile foundation. Soil corrosion rate is regarded as 0.02 mm/year regardless of the soil. However, it is considered that corrosion rates of each soil are difference. In this study, we estimated the soil corrosion environment by measuring the physical properties of soil and evaluated the charge transfer resistance of each soil environment by AC impedance method that regarded soil as electrolyte, in order to investigate the effect of soil particle size on soil corrosion.</p><p>Glass beads of uniform sphere haven't been packed close-packed structure, and porosity of soil with particle size distribution was nearly equal to regardless of particle size. But in case of the soil that included particles less than 50μm in a large quantity, porosity of the soil was increase. Porosity of soil that had similar particle size distribution was nearly equal regardless of water content. Therefore, it is suggested that the change of soil water content was replacement liquid phase and gas phase. The charge transfer resistance of soil corrosion decreased with decrease of gas phase ratio in soil. Therefore, it is suggested that the charge transfer resistance of soil corrosion might be estimated from the soil particle size distribution and water content.</p>

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• Exposure Corrosion Test of Metal Pile for Shallow Soil Layer

  Fujihashi Kenta, Okuji Makoto, Oshikawa Wataru, Tahara Akira, Shinohara Tadashi, Katayama Hideki

  Zairyo-to-Kankyo ( Japan Society of Corrosion Engineering )  67 ( 5 ) 216 - 221   2018.05 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

• VOC sensing behavior of semiconducting Sm2O3/SmFeO3 mixtures

  Yoshiteru Itagaki, Kenta Fujihashi, Hiromichi Aono, Masami Mori, Yoshihiko Sadaoka

  Journal of the Ceramic Society of Japan ( 公益社団法人 日本セラミックス協会 )  123 ( 10 ) 961 - 966   2015.06 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

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