start-ver=1.4 cd-journal=joma no-vol=7 cd-vols= no-issue=5 article-no= start-page=056402 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200504 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Synthesis of solvent-free conductive and flexible cellulose-carbon nanohorn sheets and their application as a water vapor sensor en-subtitle= kn-subtitle= en-abstract= kn-abstract=Carbon nanohorns (CNHs) are mixed with cellulose to make freestanding thin-film conductive sheets. CNHs, at different ratios (5, 10, 25, 50 wt%), form composites with cellulose (hydroxyethylcellulose). Freestanding cellulose-carbon nanohorn (CCN) sheets were fabricated using a 100 mu m-thick metal bar coater. Surfactants or any other chemical treatments to tailor the surface properties of CNHs were avoided to obtain composite sheets from pristine CNHs and cellulose. Utilizing the hygroscopic property of hydroxyethylcellulose and the electrical conductivity of CNHs paved a path to perform this experiment. The synthesis technique is simple, and the fabrication and drying of the sheets were effortless. As the loading concentration of CNH increased, the resistance, flexibility, and strength of the CCN composite sheets decreased. The maximum loading concentration possible to obtain a freestanding CCN sheet is 50 wt%. The resistance of the maximum loading concentration of CNH was 53 k omega. The response of the CCN sheets to water vapor was 4 s and recover time was 13 s, and it is feasible to obtain a response for different concentrations of water vapor. High-resolution transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, resistance measurement, tensile strength measurement, and thermogravimetric analysis were used to investigate the mechanical, morphological, electrical, and chemical properties of the CCN sheets. en-copyright= kn-copyright= en-aut-name=Paneer SelvamKarthik en-aut-sei=Paneer Selvam en-aut-mei=Karthik kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NakagawaTomohiro en-aut-sei=Nakagawa en-aut-mei=Tomohiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=MaruiTatsuki en-aut-sei=Marui en-aut-mei=Tatsuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=InoueHirotaka en-aut-sei=Inoue en-aut-mei=Hirotaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=NishikawaTakeshi en-aut-sei=Nishikawa en-aut-mei=Takeshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=HayashiYasuhiko en-aut-sei=Hayashi en-aut-mei=Yasuhiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=4 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=5 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=6 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=carbon nanohorns kn-keyword=carbon nanohorns en-keyword=cellulose kn-keyword=cellulose en-keyword=conductive sheets kn-keyword=conductive sheets en-keyword=vapor sensor kn-keyword=vapor sensor END start-ver=1.4 cd-journal=joma no-vol=24 cd-vols= no-issue=1 article-no= start-page=18 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2021 dt-pub=20211023 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Synthesis and characterization of conductive flexible cellulose carbon nanohorn sheets for human tissue applications en-subtitle= kn-subtitle= en-abstract= kn-abstract=Background
Conductive sheets of cellulose and carbon nanomaterials and its human skin applications are an interesting research aspect as they have potential for applications for skin compatibility. Hence it is needed to explore the effects and shed light on these applications.
Method
To fabricate wearable, portable, flexible, lightweight, inexpensive, and biocompatible composite materials, carbon nanohorns (CNHs) and hydroxyethylcellulose (HEC) were used as precursors to prepare CNH-HEC (Cnh-cel) composite sheets. Cnh-cel sheets were prepared with different loading concentrations of CNHs (10, 20 50,100mg) in 200mg cellulose. To fabricate the bio-compatible sheets, a pristine composite of CNHs and HEC was prepared without any pretreatment of the materials.
Results
The obtained sheets possess a conductivity of 1.83x10(-10)S/m and bio-compatible with human skin. Analysis for skin-compatibility was performed for Cnh-cel sheets by h-CLAT in vitro skin sensitization tests to evaluate the activation of THP-1 cells. It was found that THP-1 cells were not activated by Cnh-cel; hence Cnh-cel is a safe biomaterial for human skin. It was also found that the composite allowed only a maximum loading of 100mg to retain the consistent geometry of free-standing sheets of <100m thickness. Since CNHs have a unique arrangement of aggregates (dahlia structure), the composite is homogeneous, as verified by transmission electron microscopy (TEM) and, scanning electron microscopy (SEM), and other functional properties investigated by Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), conductivity measurement, tensile strength measurement, and skin sensitization.
Conclusion
It can be concluded that cellulose and CNHs sheets are conductive and compatible to human skin applications. en-copyright= kn-copyright= en-aut-name=SelvamKarthik Paneer en-aut-sei=Selvam en-aut-mei=Karthik Paneer kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NagahataTaichi en-aut-sei=Nagahata en-aut-mei=Taichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KatoKosuke en-aut-sei=Kato en-aut-mei=Kosuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=KoreishiMayuko en-aut-sei=Koreishi en-aut-mei=Mayuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=NakamuraToshiyuki en-aut-sei=Nakamura en-aut-mei=Toshiyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=NakamuraYoshimasa en-aut-sei=Nakamura en-aut-mei=Yoshimasa kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=NishikawaTakeshi en-aut-sei=Nishikawa en-aut-mei=Takeshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=SatohAyano en-aut-sei=Satoh en-aut-mei=Ayano kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=HayashiYasuhiko en-aut-sei=Hayashi en-aut-mei=Yasuhiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= affil-num=4 en-affil=Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= affil-num=5 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=6 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=7 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=8 en-affil=Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= affil-num=9 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=Carbon Nanohorns kn-keyword=Carbon Nanohorns en-keyword=Cellulose kn-keyword=Cellulose en-keyword=Skin sensitization kn-keyword=Skin sensitization en-keyword=Composites kn-keyword=Composites en-keyword=Bio-compatible kn-keyword=Bio-compatible END start-ver=1.4 cd-journal=joma no-vol=95 cd-vols= no-issue=23 article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2005 dt-pub=200511 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Opacity effect on extreme ultraviolet radiation from laser-produced tin plasmas en-subtitle= kn-subtitle= en-abstract= kn-abstract=

Opacity effects on extreme ultraviolet (EUV) emission from laser-produced tin (Sn) plasma have been experimentally investigated. An absorption spectrum of a uniform Sn plasma generated by thermal x rays has been measured in the EUV range (9-19 nm wavelength) for the first time. Experimental results indicate that control of the optical depth of the laser-produced Sn plasma is essential for obtaining high conversion to 13.5 nm-wavelength EUV radiation; 1.8% of the conversion efficiency was attained with the use of 2.2 ns laser pulses.

en-copyright= kn-copyright= en-aut-name=FujiokaShinsuke en-aut-sei=Fujioka en-aut-mei=Shinsuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NishimuraHiroaki en-aut-sei=Nishimura en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NishiharaKatsunobu en-aut-sei=Nishihara en-aut-mei=Katsunobu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=SasakiAkira en-aut-sei=Sasaki en-aut-mei=Akira kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=SunaharaAtsushi en-aut-sei=Sunahara en-aut-mei=Atsushi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=OkunoTomoharu en-aut-sei=Okuno en-aut-mei=Tomoharu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=UedaNobuyoshi en-aut-sei=Ueda en-aut-mei=Nobuyoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=AndoTsuyoshi en-aut-sei=Ando en-aut-mei=Tsuyoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=TaoYezheng en-aut-sei=Tao en-aut-mei=Yezheng kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=ShimadaYoshinori en-aut-sei=Shimada en-aut-mei=Yoshinori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=HashimotoKazuhisa en-aut-sei=Hashimoto en-aut-mei=Kazuhisa kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= en-aut-name=YamauraMichiteru en-aut-sei=Yamaura en-aut-mei=Michiteru kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=12 ORCID= en-aut-name=ShigemoriKeisuke en-aut-sei=Shigemori en-aut-mei=Keisuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=13 ORCID= en-aut-name=NakaiMitsuo en-aut-sei=Nakai en-aut-mei=Mitsuo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=14 ORCID= en-aut-name=NagaiKeiji en-aut-sei=Nagai en-aut-mei=Keiji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=15 ORCID= en-aut-name=NorimatsuTakayoshi en-aut-sei=Norimatsu en-aut-mei=Takayoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=16 ORCID= en-aut-name=NishikawaTakeshi en-aut-sei=Nishikawa en-aut-mei=Takeshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=17 ORCID= en-aut-name=MiyanagaNoriaki en-aut-sei=Miyanaga en-aut-mei=Noriaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=18 ORCID= en-aut-name=IzawaYasukazu en-aut-sei=Izawa en-aut-mei=Yasukazu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=19 ORCID= en-aut-name=MimaKunioki en-aut-sei=Mima en-aut-mei=Kunioki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=20 ORCID= affil-num=1 en-affil= kn-affil=Osaka University affil-num=2 en-affil= kn-affil=Osaka University affil-num=3 en-affil= kn-affil=Osaka University affil-num=4 en-affil= kn-affil=Advanced Photon Research Center affil-num=5 en-affil= kn-affil=Institute for Laser Technology affil-num=6 en-affil= kn-affil=Osaka University affil-num=7 en-affil= kn-affil=Osaka University affil-num=8 en-affil= kn-affil=Osaka University affil-num=9 en-affil= kn-affil=Osaka University affil-num=10 en-affil= kn-affil=Institute for Laser Technology affil-num=11 en-affil= kn-affil=Institute for Laser Technology affil-num=12 en-affil= kn-affil=Institute for Laser Technology affil-num=13 en-affil= kn-affil=Osaka University affil-num=14 en-affil= kn-affil=Osaka University affil-num=15 en-affil= kn-affil=Osaka University affil-num=16 en-affil= kn-affil=Osaka University affil-num=17 en-affil= kn-affil=Okayama University affil-num=18 en-affil= kn-affil=Osaka University affil-num=19 en-affil= kn-affil=Osaka University affil-num=20 en-affil= kn-affil=Osaka University en-keyword=emission kn-keyword=emission en-keyword=targets kn-keyword=targets en-keyword=lithography kn-keyword=lithography en-keyword=fusion kn-keyword=fusion END start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=1 article-no= start-page=7307 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200429 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Controlling Electronic States of Few-walled Carbon Nanotube Yarn via Joule-annealing and p-type Doping Towards Large Thermoelectric Power Factor en-subtitle= kn-subtitle= en-abstract= kn-abstract=Flexible, light-weight and robust thermoelectric (TE) materials have attracted much attention to convert waste heat from low-grade heat sources, such as human body, to electricity. Carbon nanotube (CNT) yarn is one of the potential TE materials owing to its narrow band-gap energy, high charge carrier mobility, and excellent mechanical property, which is conducive for flexible and wearable devices. Herein, we propose a way to improve the power factor of CNT yarns fabricated from few-walled carbon nanotubes (FWCNTs) by two-step method; Joule-annealing in the vacuum followed by doping with p-type dopants, 2,3,5,6-tetrafluo-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). Numerical calculations and experimental results explain that Joule-annealing and doping modulate the electronic states (Fermi energy level) of FWCNTs, resulting in extremely large thermoelectric power factor of 2250 mu Wm(-1) K-2 at a measurement temperature of 423K. Joule-annealing removes amorphous carbon on the surface of the CNT yarn, which facilitates doping in the subsequent step, and leads to higher Seebeck coefficient due to the transformation from (semi) metallic to semiconductor behavior. Doping also significantly increases the electrical conductivity due to the effective charge transfers between CNT yarn and F4TCNQ upon the removal of amorphous carbon after Joule-annealing. en-copyright= kn-copyright= en-aut-name=MyintMay Thu Zar en-aut-sei=Myint en-aut-mei=May Thu Zar kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NishikawaTakeshi en-aut-sei=Nishikawa en-aut-mei=Takeshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OmotoKazuki en-aut-sei=Omoto en-aut-mei=Kazuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=InoueHirotaka en-aut-sei=Inoue en-aut-mei=Hirotaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=YamashitaYoshifumi en-aut-sei=Yamashita en-aut-mei=Yoshifumi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=KyawAung Ko Ko en-aut-sei=Kyaw en-aut-mei=Aung Ko Ko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=HayashiYasuhiko en-aut-sei=Hayashi en-aut-mei=Yasuhiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=4 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=5 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=6 en-affil=Department of Electrical and Electronic Engineering, Southern University of Science and Technology kn-affil= affil-num=7 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=Materials science kn-keyword=Materials science en-keyword=Nanoscience and technology kn-keyword=Nanoscience and technology END