N. Ohtsu, K. Yonemoto, A. Yoshino, Y. Kitadate, M. Nakai, M. Hirano, Wear resistance improvement of steinles sttel by a facile laser surface processing,
The14th TSME International Conference on Mechanical Engineering, TSME-ICOME 2024 (12/10-13,Pattaya, Thailand)
(Invited)N. Ohtsu, An open atmosphere laser nitriding on metal surfaces utilizing a laser induced plasma,
6th Asia Conference on Material and Manufacturing Technology, ACMMT 2024 (11/25-28, Online)
M. Hirano, K. Maruyama, N. Ohtsu, Enhancing hardness of commercial pure Ti via radio-frequency magnetron He plasma,
The 12th Vacuum and Surface Science Confernce of Asia and Australia, VASSCAA-12 (10/13-17, Taipei, Taiwan)
N. Ohtsu, A. Yoshino, K. Yonemoto, An open atmosphere nitriding phenomenon on metal surfaces triggered by laser induced plasma,
19th Conference on Plasma Surface Engineering, PSE 2024 (9/2-5, Erfurt, Germany)
K. Yonemoto, A. Yoshino, Y. Kitadate, N. Ohtsu, Characteristic variation of the focused pulsed laser-irradiated titanium surface in N2-O2 atmosphere with different mixture ratio,
19th Conference on Plasma Surface Engineering, PSE 2024 (9/2-5, Erfurt, Germany)
A. Yoshino, K. Yonemoto, Y. Kitadate, T. Kiba, N. Ohtsu, Optimization of laser-induced plasma for facilitating the open atmosphere laser nitriding on titanium surface,
19th Conference on Plasma Surface Engineering, PSE 2024 (9/2-5, Erfurt, Germany)
N. Ohtsu, R. Takada R. Kawakami, Dominant characteristic of an anodized NiTi alloy surface that suppress a Ni ion release in biological environment,
European Conference on Application of Surface and Interface Analysis, ECASIA 2024 (6/9-14,Gothenburg,Sweden)
N. Ohtsu, A. Tsuruta, R. Kawakami, M. Hirano, Fabrication of high durability photocatalytic N-doped TiO2 layer
on Ti substrate through anodization in hot non-aqueous nitrate electrolyteals,
The International Conference on Applied Physics and Materials Applications, ICAPMA2023 (12/6-9, Pattaya, Thailand)
(Invited) N. Ohtsu, H. Taniho, K. Tate, Z. Wang, M. Ohta, Pulsed anodization to improve the
biocompatibility of superelastic NiTi alloy, The 11th Pacific Rim International Conference on Advanced Materials and Processing,
PRICM 11 (11/19-23, Jeju, Korea)
Y. Matsui, R. Kawakami, Y. Sakurai, N. Ohtsu, Endothelial cell behavior on pulsed-anodized NiTi alloys using different electrolytes
, The 11th Pacific Rim International Conference on Advanced Materials and Processing,
PRICM 11 (11/19-23, Jeju, Korea)
R. Kawakami, Y. Matsui, R. Takada, N. Ohtsu, Variation of Ni ion release behavior of a pulsed-anodized NiTi alloy
surface by a voltage setting , The 11th Pacific Rim International Conference on Advanced Materials and Processing,
PRICM 11 (11/19-23, Jeju, Korea)
N. Ohtsu,
An open atmosphere nitriding phenomenon on metal surfaces triggered by laser induced plasma,
Euromat'2023 (9/3-7, Frankfurt, Germany)
R. Kawakami, K.Tate, Y. Matsui, A. Tsuruta, N. Ohtsu, Variation of Ni-ion
release behaviour of the pulsed anodized NiTi alloy by the adjustment of
pulse waveform, International Conference on Processing & Manufacturing
of Advanced Materials, Thermec'2023 (7/2-7, Vienna, Austria)
(Invited) N. Ohtsu, R. Endo, S. Takeda An open atmosphere nitriding phenomenon on
metal surfaces triggered by laser induced plasma , International Conference
on Processing & Manufacturing of Advanced Materials, Thermec'2023 (7/2-7,
Vienna, Austria)
Y. Sakuraba, N. Ohtsu, R. Kawakami, Hardness distribution generation in
a welded AISI H13 steel and its removal by laser heat treatment, International
Conference on Processing & Manufacturing of Advanced Materials, Thermec'2023
(7/2-7, Vienna, Austria)
(Invited)N. Ohtsu,
An open atmosphere laser nitridng process on titanium,
2nd International Materials Engineering and Advanced Manufacturing Technologies Congress, IMEAMTC'23,
(1/12〜13, Online)
N. Ohtsu, Fractional Analysis Process of Surface-Adsorbed Proteins Using Sds-Page,
Pacific Rim Symposium on Surface, Coatings & Interface, PacSurf 2022
(12/11〜15, Hawaii)
K. Tate、Y. Matsui, R. Kawakami, N. Ohtsu,
Cell responses on pulsed-anodized nitinol alloy with different surface property,
6th International Conference on Nanomaterials and Biomaterials,ICNB 2022 (11/12〜14, Bangkok)
S. Takeda, M. Hiranoi, N. Ohtsu,
Fabrication of antibacterial nanopillars on AISI 316 surface via argon plasma etchingprocess,
4th Asia Conference on Material and Manufacturing Technology, ACMMT 2022 (11/12〜14, Bangkok)
R. Endo, S. Takeda, N. Ohtsu,
A nitride layer formation on titanium surface through laser irradiation in an open atmospheric condition,
4th Asia Conference on Material and Manufacturing Technology, ACMMT 2022 (11/12〜14, Bangkok)
M. Hirano, S. Taleda, N. Ohtsu,
Effect of crystal phase and composition of stainless steels on antibacterial nanopillar surface fabricated by argon plasma etching,
22th International Vacuum Congress, IVC-22 (9/11〜16, Sapporo)
H. Taniho, K. Tate、R. Kawakami, N. Ohtsu,
Characteristic variation of pulsed anodized NiTi surface caused by the voltage-OFF period,
Materials Research Meetin 2021, MRM2021(12/13〜16, Yokohama)
K.Tate, H. Taniho, R. Kawakami, N. Ohtsu,
Cell responses on a pulsed anodized NiTi surface with a different Ni releasing behavior,
Materials Research Meetin 2021, MRM2021(12/13〜16, Yokohama)
Y. Yotsuji, Y. Funane, N. Ohtsu,
Investigation of photocatalytic antiviral performance on an anodized titanium surface using a temperature-controlled alcoholic nitrate electrolyte,
Materials Research Meetin 2021, MRM2021(12/13〜16, Yokohama)
(Invited) N. Ohtsu, H. Taniho, K. Tate, Z. Wang, M. Ohta
Biological responses on a surface modified nitinol alloy through the anodization technique,
18th International Conference on Flow Dynamics, ICFD2021,(10/27-29, Virtual)
K. Yamasaki, H. Taniho, K. Tate, N, Ohtsu,
Ni ion release from a pulsed anodized NiTi alloy surface using various electrolytes,
14th Inbternarional COnference on Surfaces, Coatings and Nanostructured Materials, NANOSMAT 2020 (9/8〜10, Virtual)
M.Hirano, S. Takeda, K. Miura, M. Yamane, N. Ohtsu,
Fabrication of antibacterial nanopillars on stainless steel surface ,
14th Inbternarional COnference on Surfaces, Coatings and Nanostructured Materials, NANOSMAT 2020 (9/8〜10, Virtual)
H. Taniho, K. Yamasaki, N. Ohtsu,
Enhancement of Ni release inhibition effect on pulsed anodized NiTi alloy through the pulse width optimization,
14th Inbternarional COnference on Surfaces, Coatings and Nanostructured Materials, NANOSMAT 2020 (9/8〜10,Virtual)
Y.Funane, S. Yotsuji, N. Ohtsu,
Improvement of performances on anodic TiO2 layer using nitrate/non-aqueous electrolyte via temperatures optimization,
14th Inbternarional COnference on Surfaces, Coatings and Nanostructured Materials, NANOSMAT 2020 (9/8〜10,Virtual)
M.Hirano, K. Miura, M. Yamane, N. Ohtsu,
Fabrication of antibacterial nanopillars on stainless steel surface,
11th World Biomaterials Congress, WBC 2020 (12/11〜15, Virtual)
N. Ohtsu, T. Kawakami, Y. Konaka, K. Kuroda,
Establishment of fractional determination process of adsorbed proteins on titanium surface using SDS-PAGE,
11th World Biomaterials Congress, WBC 2020 (12/11〜15, Virtual)
N. Ohtsu, M. Gotoh, Y. Kohari, Y. Shimotori, T.-Y. Chiou, Y. Nagata, H. Arai, M. Murata,
Production of antimicrobial agent from a peppermint herbal water,
International Conference on Functional Materials and Chemical Engineering, ICFMCE 2019 (12/15〜17, Bangkok, Thailand)
N. Ohtsu, T. Kawakami, Y. Konaka, K. Kuroda,Fractional analytical procedure for adsorbed proteins onto a material surface,
International Conference on Materials and Systems for Sustainability, ICMaSS 2019 (11/1〜3, Nagoya, Japan)
R. Kuroda, K. Kuroda, M. Okido, K. Yamaguchi, N. Ohtsu, Antibacterial Properties of Ti Surface Using Metallic Ions Adsorption,
International Conference on Materials and Systems for Sustainability, ICMaSS 2019 (11/1〜3, Nagoya, Japan)
K. Yamasaki, K. Takiguchi, S. Komai, N. Ohtsu, Surface characteristics and Ni ion release behavior of anodized NiTi alloy surface
using the mixed electrolyte comprising HNO3 and H3PO4 ,
International Conference on Materials and Systems for Sustainability, ICMaSS 2019 (11/1〜3, Nagoya, Japan)
K. Miura,M. Yamane, N. Ohtsu, Phase control of the plasma-nitrided SUS316 surface by N2 and H2 gas mixture ratio,
International Conference on Materials and Systems for Sustainability, ICMaSS 2019 (11/1〜3, Nagoya, Japan)
N. Ohtsu, M. Oku, K. Wagatsuma, XPS spectra of clean metallic silicide surfaces obtained by in-situ fracture,
European Conference on Application of Surface and Interface Analysis, ECASIA 2019 (9/16〜20, Dresden, Germany)
T. Kawakami, H. Sawagucti, T. Syouji, N. Ohtsu, Effect of the surface chemical state on competitive protein adsorption on titanium surface
: A combinational analysis using SDS-PAGE and XPS,
European Conference on Application of Surface and Interface Analysis, ECASIA 2019 (9/16〜20, Dresden, Germany)
S. Komai, M. Hirano, N. Ohtsu, Characterization of strontium-contained apatite layer fabricated
using calcium-phosphate slurry processing,
European Conference on Application of Surface and Interface Analysis, ECASIA 2019 (9/16〜20, Dresden, Germany)
K. Yamaguchi, Y. Funane, Y. Konaka, N. Ohtsu, Characteristics of anodic oxide layer on titanium substrate
using nitrate electrolyte in various alcohols as solvent,
European Conference on Application of Surface and Interface Analysis, ECASIA 2019 (9/16〜20, Dresden, Germany)
M. Hirano, M. Yamane, N. Ohtsu, Hydrophilic properties of plasma-treated titanium surface
: Effect of gas composition and discharge modes,
European Conference on Application of Surface and Interface Analysis, ECASIA 2019 (9/16〜20, Dresden, Germany)
K. Takiguchi, M. Yamane, N. Ohtsu, Surface modification of pure iron through a focused pulse Nd: YAG laser
irradiation in nitrogen atmosphere,
European Conference on Application of Surface and Interface Analysis, ECASIA 2019 (9/16〜20, Dresden, Germany)
S. Komai, M. Hirano, N. Ohtsu, Preparation of strontium-doped apatite layer
on titanium substrate through calcium phosphate slurry processing and ion release from the layer,
International Symposium for Advanced Materials Research, ISAMR 2019 (8/22〜25, Kaohsiung, Taiwan)
K. Takuguchi, K. Yamasaki, N. Ohtsu, Effect of anion species and concentration in electrolyte on NiTi anodization,
International Symposium for Advanced Materials Research, ISAMR 2019 (8/22〜25, Kaohsiung, Taiwan)
K. Yamaguchi, Y. Funane, N. Ohtsu, Comparison of anodized layer on titanium
using nitrate electrolyte in various alcohol solvents for investigating layer growth mechanism,
International Symposium for Advanced Materials Research, ISAMR 2019 (8/22〜25, Kaohsiung, Taiwan)
(Invited) N. Ohtsu ,
Simple chemical treatment process to give osteoconductivity and antibacterial efficacy on titanium implant ,
International Symposium for Advanced Materials Research, ISAMR 2019 (8/22〜25, Kaohsiung, Taiwan)
N. Ohtsu, Y. Hirano, K. Yamaguchi, K. Yamasaki, Surface characteristics, Ni ion release,
and antibacterial efficacy of anodized NiTi alloy using HNO3 electrolyte of various concentrations,
International Conference on Applied Surface Science, ICASS 2019 (6/17〜20, Pisa, Italy)
K. Yamaguchi, Y. Konaka, N. Ohtsu, Fabrication of a photocatalytic
antibacterial layer on a Ti material through anodization with nitrate/glycerol electrolyte,
Anodizing Science Technology, AST 2019 (6/2〜5, Awaji, Japan)
N. Ohtsu, Y. Hirano, K. Takiguchi, K. Yamasaki,
Oxide layer growth on nickel-titanium alloy through anodization ,
Anodizing Science Technology, AST 2019 (6/2〜5, Awaji, Japan)
N. Ohtsu, T.Kuji, M. Hirano, Roles of Anodic Oxide Layer on the Improvement
of Cellular Response of Titanium Implan, Pacific Rim Symposium on Surface,
Coatings & Interface, Pacsurf 2018 (12/2〜6, Waikoloa, Hawaii)
N. Ohtsu, Y. Hirano, H. Arai, Control of Ni ion release from NiTi shape memory alloy using
anodization in HNO3 electrolyte, 18th Asia Pacific Corrosion Control COnference,
APCCC-18 (11/5〜9, Pattaya, Thailand)
N. Ohtsu, Y. Hirano, Corrosion behavior of nickel-titanium alloy with TiO2
layer formed via anodization in HNO3 electrolytes, The 9th Vacuum and Surface Science
Conferene of Asia and Australia, VASSCAA-9 (8/13〜16, Sydney, Australia)
K. Sakamoto, F. Hayashi, N. Ohtsu, Formation of Ni-free oxide layer on
NiTi alloy by a combination of chemical and thermal treatments, THERMEC'2018
-International Conference on processing & manufacturing of advanced
materials (7/8〜13, Paris, France)
(Invited) N. Ohtsu, T. Kuji, M. Hirano, Effects of processing
voltage on cellular response of titanium anodized in phosphoric acid electrolyte,
THERMEC'2018 -International Conference on processing & manufacturing
of advanced materials (7/8〜13, Paris, France)
N. Ohtsu, Y. Kakuchi, T. Ohtsuki, Y. Yokoiwa, Antibacterial efficacy of hydroxyapatite coating including Zn formed by chemical solution deposition,
2nd International Conference on Applied Surface Science (6/12〜15, Dalian, China)
N. Ohtsu, Y. Hirano, Comparison of nickel-titanium alloy surface anodized in phosphoric- and sulfuric-acid electrolytes,
17th European Conference on Applications of Surface and Interface Analysis (9/24〜29, Montpellier, France)
(Invited) N. Ohtsu, Y. Kakuchi, Y. Yoshida, Antibacterial hydroxyapatite coating on titanium via a simple chemical treatment process using calciunm phosphate slurry,
18th International Union of Materials Research Society - Internationa Conference in Asia (11/5〜9, Taipei, Taiwan)
Y. Hirano, N. Ohtsu, Effect of HNO3 concentration on the surface morphology and layer thickness of the anodic oxide layer on NiTi alloy,
18th International Union of Materials Research Society - Internationa Conference in Asia (11/5〜9, Taipei, Taiwan)
M. Bai, N. Ohtsu, Effect of water addition to NH4NO3/ethylene glycol electrolyte on the growth of anodic layer on titanium,
18th International Union of Materials Research Society - Internationa Conference in Asia (11/5〜9, Taipei, Taiwan)
N. Ohtsu, H. Arai, Calcium-phosphate slurry processing: a novel chemical treatment technique to activate osteogenesis on titanium,
10nd World Biomaterials Congress (5/17〜22, Montreal, Canada)
N. Ohtsu, T. Kozuka, M. Yamane, K. Ishikawa, Improvement of high temperature stability of Pd-coated Nb using surface plasma nitriding,
15th International Symposium on Metal-Hydrogen System (8/7〜12, Interlaken, Switzerland)
Y. Hirano, Y. Kakuchi, N. Ohtsu, A chemically stable TiO2 layer formation on NiTi alloy by electrochemical process,
Pure and Applied Chemistry International Conference 2017 (2/2〜3, Bangkok, Thai)