The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform

Junji Nishii - One of the best experts on this subject based on the ideXlab platform.

  • Surface relief hologram formed by selective SiO2 deposition on soda-lime silicate glass.
    PLOS ONE, 2019
    Co-Authors: Daisuke Sakai, Keiga Kawaguchi, Kenji Harada, Hiroyuki Shibata, Junji Nishii
    Abstract:

    We propose the fabrication of surface relief holograms via selective SiO2 deposition on soda-lime silicate glass substrates. Initially, the original hologram was recorded on an azobenzene photosensitive polymer film coated on the soda-lime silicate glass by irradiation with a conventional continuous wave Ar+ laser with a wavelength of 514.5 nm. The hologram was transferred to the soda-lime silicate glass surface via a Corona Discharge Treatment as an index modulation hologram, which was created by partial substitution of protons for sodium ions during the Corona Discharge Treatment in air. After the Corona Discharge Treatment, the polymer film was removed from the substrate. The diffraction efficiency of the index hologram on the soda-lime silicate glass was estimated to be 5.8 × 10−2% at a wavelength of 532 nm. Finally, the glass substrate was subjected to Corona Discharge Treatment in air with vaporized cyclic siloxane. A surface relief hologram with the diffraction efficiency of 2.3% was successfully fabricated on the soda-lime silicate glass.

  • dense proton injection into phosphate glasses using Corona Discharge Treatment
    Applied Surface Science, 2018
    Co-Authors: Takuya Kinoshita, Keiga Kawaguchi, Daisuke Sakai, Atsushi Miyazaki, Takuya Yamaguchi, Takahisa Omata, Tomohiro Ishiyama, Masaya Fujioka, Hideo Kaiju, Junji Nishii
    Abstract:

    Abstract Sodium ions in 25NaO 1/2 -6LaO 3/2 -6GeO 2 -63PO 5/2 (mol%) glasses were substituted with protons using Corona Discharge Treatment (CDT) under a H 2 atmosphere. The substitution of sodium ion to proton proceeded from the anode side to the cathode side with constant current flow during the CDT. A crystalline free and transparent glass plate of 0.3 mm thickness was obtained after CDT for 96 h. The maximum decrease rate from sodium ion to proton was 78 ± 10%. The proton conductivity of 8.5 × 10 −4 S/cm was attained at 400 °C.

  • alkali ion migration between stacked glass plates by Corona Discharge Treatment
    Applied Surface Science, 2015
    Co-Authors: Keiga Kawaguchi, Daisuke Sakai, Shiro Funatsu, Keiichiro Uraji, Kiyoshi Yamamoto, Toshio Suzuki, Kenji Harada, Hiroshi Ikeda, Junji Nishii
    Abstract:

    Abstract Corona Discharge reflects the spatial migration of alkali ions over a gap between two glass plates. This study examined stacked glass plates containing different alkali ions treated with the Corona Discharge plasma generated by applied voltage of 4.5 kV at 200 °C. Protons generated at the anode electrode penetrate into the potassium-ion-containing upper glass plate, which is located 5 mm below the anode electrode. Potassium ions intruded into the lower glass plate containing sodium ions placed on the cathode electrode, even over a 1 mm gap separating the plates. Finally, the sodium ion Discharged on the cathode electrode. The hydrogen atmosphere was effective at inhibiting the potassium ion reaction with ambient gases during the spatial migration between the two glass plates.

  • accelerated formation of sodium depletion layer on soda lime glass surface by Corona Discharge Treatment in hydrogen atmosphere
    Applied Surface Science, 2014
    Co-Authors: Keiga Kawaguchi, H Ikeda, Daisuke Sakai, Shiro Funatsu, Keiichiro Uraji, Kiyoshi Yamamoto, Toshio Suzuki, Kenji Harada, Junji Nishii
    Abstract:

    Formation of a sodium depletion layer on a soda lime glass surface was accelerated efficiently using a Corona Discharge Treatment in H2 atmosphere. One origin of such acceleration was the preferential generation of H+ with a larger mobility at an anode needle end with a lower applied voltage than that in air. The second origin was the applied voltage across the glass plate during the Corona Discharge Treatment, which was estimated theoretically as 2.7 times higher than that in air. These two effects doubled the depletion layer thickness compared with that in air.

Guizhen Ke - One of the best experts on this subject based on the ideXlab platform.

  • effects of Corona Discharge Treatment on the surface properties of wool fabrics
    Journal of Materials Processing Technology, 2008
    Co-Authors: Weilin Xu, Guizhen Ke, Weidong Yu, Xiaolin Shen
    Abstract:

    Wool fabric was treated by Corona Discharge and treating conditions were optimized. The surface properties of the treated wool fabrics, such as hydrophilicity and dyeability with natural dyes, have been investigated. After the Corona Discharge Treatment, the hydrophilicity of the wool fabric was improved and the dyeability with Rhizoma coptidis was increased. Scanning electron microscope (SEM) images indicated that some epicuticle scales on the wool surface became loose. The X-ray photoelectron spectroscopic (XPS) analyses show the oxygen contents of the wool surface were increased and sulphur contents decreased after Treatment.

Gilson Khang - One of the best experts on this subject based on the ideXlab platform.

  • Adhesion comparison of human bone marrow stem cells on a gradient wettable surface prepared by Corona Treatment
    Applied Surface Science, 2008
    Co-Authors: Yu Na Shin, Gilson Khang
    Abstract:

    Corona Discharge Treatment was applied to modify the surface of polyethylene (PE). The wettability of PE surface was gradually increased by power increase of a Corona Treatment along the PE length, indicating that the hydrophilicity of PE surface increased gradually. The adhesion and proliferation behavior of human bone marrow stem cells (hBMSCs) on the gradient PE surface was evaluated. We found that hBMSCs were adhered to and proliferated on better highly hydrophilic than hydrophobic surfaces. The plot of proliferation rate vs. the water contact angles was parabolic. These results indicate that surface wettability plays an important role in the cell attachment and proliferation.

  • Proliferation rate of fibroblast cells on polyethylene surfaces with wettability gradient
    Journal of Applied Polymer Science, 2004
    Co-Authors: Jong-hwa Choee, John M. Rhee, Gilson Khang
    Abstract:

    Surface wettability on anchorage-dependent cells has an important role in cell growth rate. In our previous studies, we prepared a wettability gradient on polyethylene (PE) surfaces using Corona Discharge Treatment from a knife-type electrode whose power increased gradually along the sample length. The PE surfaces were oxidized gradually with increasing power and characterized by Fourier transform infrared spectroscopy, contact angle goniometry, and electron spectroscopy for chemical analysis. The purpose of this study is to determine the rate of proliferation on polymer surfaces with different wettability. The behavior of cell growth for NIH/3T3 fibroblast cells attached on the polymer surfaces with different hydrophilicity was investigated using wettability gradient PE surfaces prepared by Corona Discharge Treatment. They were investigated for the number of grown cells from 24 to 60 h in terms of surface wettability. From the slope of cell number on PE gradient surface versus culture time, the proliferation rates (number of cell/cm2 · h) were calculated. It was observed that the proliferation rate was increased more on positions with moderate hydrophilicity of the wettability gradient surface than on the more hydrophobic or hydrophilic positions, i.e., 1111 (number of cell/cm2 · h) of 57° of water contact angle at the 2.5-cm position (P < 0.05). This result seems closely related to the serum protein adsorption on the surface: the serum proteins were also adsorbed more on the moderately hydrophilic surface. In conclusion, surface wettability plays an important role in cell adhesion, spreading, and proliferation on the polymer surfaces. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 599–606, 2004

  • The effect of surface wettability on induction and growth of neurites from the PC-12 cell on a polymer surface.
    Journal of colloid and interface science, 2003
    Co-Authors: Gilson Khang
    Abstract:

    Abstract Surface properties of polymeric devices that are used to regenerate nervous damage are a point to be considered for axon regeneration in nerve system. In our previous studies, we prepared a wettability gradient on polyethylene (PE) surfaces using a Corona Discharge Treatment from a knife-type electrode whose power increases gradually along the sample length. The PE surfaces were oxidized gradually with increasing power. The effect of surface wettability on the different types of cells has an important role for cell adhesion and proliferation. The purpose of this study is to investigate neurite formation on polymer surfaces with different wettability. Induction and growth of neurites from the rat pheochromocytoma (PC-12) cells attached on the polymer surfaces with different hydrophilicity were investigated using the wettability gradient PE surfaces prepared by a Corona Discharge Treatment. Neurites were investigated for number and length of neurites in terms of surface wettability. It was observed that neurite formation of PC-12 cells was increased more onto the positions with moderate hydrophilicity of the wettability gradient surface than onto the more hydrophobic or hydrophilic positions. From those results, it could be assumed that initial adhesion of PC-12 cells was caused by more calf serum (CS) protein than nerve growth factor (NGF), whereas the neurite formation of PC-12 cells was caused by more NGF than CS protein. It follows from what has been said thus far that PC-12 cells are a differentiated neuronal phenotype with a long neurite at around the position 2.5 cm (water contact angle of about 55 deg). In conclusion, surface wettability plays an important role for neurite formation on the polymer surfaces for axon regeneration.

  • Interactions of proteins and cells on functional group gradient surfaces
    Macromolecular Symposia, 1997
    Co-Authors: Gilson Khang
    Abstract:

    Charge gradient and comb-like polyethylene oxide (PEO) gradient surfaces were prepared on low density polyethylene (PE) sheets by Corona Discharge Treatment with gradually increasing power and the following graft copolymerization of chargeable functional group- and PEO-containing vinyl monomers, respectively. Those gradient surfaces were used to investigate protein or cell interactions in relation to the surface functional groups and their density of polymeric materials.

  • characterization of wettability gradient surfaces prepared by Corona Discharge Treatment
    Journal of Colloid and Interface Science, 1992
    Co-Authors: Gilson Khang, Mu Shik Jhon
    Abstract:

    Abstract A new method for preparing wettability gradients on polymer surfaces was developed. Wettability gradients were produced on low density polyethylene surfaces by treating the polymer sheets in air with Corona from a knife-type electrode whose power gradually increases along the sample length. The wettability gradient surfaces prepared by the Corona Discharge Treatment were characterized by the measurement of water contact angle, Fourier-transform infrared spectroscopy in the attenuated total reflectance mode, electron spectroscopy for chemical analysis, and scanning electron microscopy. The gradient surfaces prepared can be used to systematically investigate the interactions of biological species in terms of the surface hydrophilicity/hydrophobicity of polymeric materials.

Xiaolin Shen - One of the best experts on this subject based on the ideXlab platform.

  • effects of Corona Discharge Treatment on the surface properties of wool fabrics
    Journal of Materials Processing Technology, 2008
    Co-Authors: Weilin Xu, Guizhen Ke, Weidong Yu, Xiaolin Shen
    Abstract:

    Wool fabric was treated by Corona Discharge and treating conditions were optimized. The surface properties of the treated wool fabrics, such as hydrophilicity and dyeability with natural dyes, have been investigated. After the Corona Discharge Treatment, the hydrophilicity of the wool fabric was improved and the dyeability with Rhizoma coptidis was increased. Scanning electron microscope (SEM) images indicated that some epicuticle scales on the wool surface became loose. The X-ray photoelectron spectroscopic (XPS) analyses show the oxygen contents of the wool surface were increased and sulphur contents decreased after Treatment.

Weidong Yu - One of the best experts on this subject based on the ideXlab platform.

  • effects of Corona Discharge Treatment on the surface properties of wool fabrics
    Journal of Materials Processing Technology, 2008
    Co-Authors: Weilin Xu, Guizhen Ke, Weidong Yu, Xiaolin Shen
    Abstract:

    Wool fabric was treated by Corona Discharge and treating conditions were optimized. The surface properties of the treated wool fabrics, such as hydrophilicity and dyeability with natural dyes, have been investigated. After the Corona Discharge Treatment, the hydrophilicity of the wool fabric was improved and the dyeability with Rhizoma coptidis was increased. Scanning electron microscope (SEM) images indicated that some epicuticle scales on the wool surface became loose. The X-ray photoelectron spectroscopic (XPS) analyses show the oxygen contents of the wool surface were increased and sulphur contents decreased after Treatment.