Search Results 1-20 of 55

  • 1 / 3
  • Sub-Microsecond TADF Emission in D-D′-A Emitters

    Auffray Morgan , Balijapalli Umamahesh , Ribierre Jean-Charles , Tsuchiya Youichi , Adachi Chihaya

    … Due to different molecular configurations of the emitters, multiple triplet states were detected and happen to drive one thermally activated delayed fluorescence (TADF) with very short lifetime of the order of nanoseconds. … A longer TADF component of microsecond order was also observed, thus showing an interesting case of dual upconversion. … These results reveal how TADF becomes efficient enough to overwhelm the prompt fluorescence with the assistance of vibrational and rotational motions.</p> …

    Chemistry Letters 49(8), 932-935, 2020

    J-STAGE 

  • Acute hepatotoxicity of multimodal targeted imaging contrast agent NaLuF<sub>4</sub>:Gd,Yb,Er-PEG/PEI-FA in mice

    Chen Yuan , Hou Mingsheng , Xu Lin , Yu Zhangsen , Fei Xiaoxiao , Ye Chenqiao , Qian Qinqing , Ye Zhiqiu , Xie Siqi , Chen Jiamin , Zhu Mingliao , Ran Na

    … <p>In the past few decades, upconversion nanoparticles (abbreviated as UCNPs) have been more widely applied in the biomedical fields, such as <i>in vitro</i> … upconversion fluorescent bioimaging, photodynamic therapy, biological macromolecular detection, imaging mediated drug delivery and so on. … But meanwhile, there is still not much research on the acute toxicity of upconversion nanoparticles <i>in vivo</i>, such as acute hepatotoxicity. …

    The Journal of Toxicological Sciences 44(9), 621-632, 2019

    J-STAGE  Ichushi Web 

  • Photon Upconversion Dyes System with Red to Yellow Wavelength Conversion Function

    YAMANE Hirokazu , KAWAHARA Mayo , TAKATOKI Genta , TAGUCHI Masataka , YAMASAKI Yasuhiro , NAGAMURA Toshihiko

    … <p>Photon upconversion (UC) is a technique to convert long wavelength light into short wavelength light. … UC fluorescence by triplet-triplet annihilation (TTA) follows a mechanism involving two kinds of molecules as sensitizer and emitter. …

    IEICE Transactions on Electronics E102.C(2), 107-112, 2019

    J-STAGE 

  • Near-Infrared to Visible Upconversion Emission Induced Photopolymerization: Polystyrene Shell Coated NaYF<sub>4</sub> Nanoparticles for Fluorescence Bioimaging and Nanothermometry

    Kamimura Masao , Yano Yuto , Kuraoka Shuhei , Suyari Satoru , Ube Takuji , Wortmann Laura , Soga Kohei

    … In this study, upconversion (UC) photopolymerization of non-polar polystyrene (PSt) shells on rare-earth doped ceramic nanophosphors (RED-CNPs) was investigated to improve the optical properties. … NPs are promising candidates for fluorescence imaging and as nanothermometry agents. …

    Journal of Photopolymer Science and Technology 30(3), 265-270, 2017

    J-STAGE 

  • Enhanced Red Upconversion Emission of NaYF<sub>4</sub>:Yb<sup>3+</sup>, Er<sup>3+</sup>, Mn<sup>2+</sup> Nanoparticles for Near-infrared-induced Photodynamic Therapy and Fluorescence Imaging

    Kamimura Masao , Omoto Ayumu , Chiu Hsin-Cheng , Soga Kohei

    … The MnUNPs showed tissue-penetrable over-1000 nm (OTN-) near-infrared (NIR) and strong red upconversion (UC) emission under NIR excitation. …

    Chemistry Letters 46(8), 1076-1078, 2017

    J-STAGE 

  • Effect of Substituents at the 4,7-Positions on the Structural Change Dynamics of Cu(I) Bis(phenanthroline) Complexes in the MLCT Excited State

    Iwamura Munetaka , Kobayashi Fumiaki , Nozaki Koichi

    … In this work, the structural change dynamics of Cu(I) bis(phenanthroline) complexes with substituents at the 4,7-positions of the ligands were investigated using femtosecond fluorescence upconversion measurements. …

    Chemistry Letters 45(2), 167-169, 2016

    J-STAGE 

  • Effects of Silver and Gold Nanoparticles on Photon Upconversion Based on Sensitized Triplet-Triplet Annihilation

    Yonemura Hiroaki , Naka Yuji , Matsumoto Ryuji , Yamada Sunao

    … Effects of silver nanoparticle (AgNP) and gold nanoparticle (AuNP) on photon upconversion based on sensitized triplet-triplet annihilation were examined in the system of platinum(II) octaethylporphyrin (PtOEP) and 9,10-diphenylanthracene (DPA). … In the sandwich samples, the enhancements of upconversion fluorescence from DPA were observed in the presence of AgNP, while the quenching of the upconversion fluorescence in the presence of AuNPs. …

    Transactions of the Materials Research Society of Japan 40(3), 195-201, 2015

    J-STAGE 

  • Surface structure of Er<sup>3+</sup>-doped LaOCl nanophosphors modified using acetyl chloride

    KONISHI Tomoya , NII Saori , ITAMI Shin , NISHIWAKI Nagatoshi

    Upconversion emissive ceramic nanophosphors like Er<sup>3+</sup>-doped LaOCl are useful for advanced security printings and fluorescence bioimaging techniques. …

    Journal of the Ceramic Society of Japan 122(1427), 561-564, 2014

    IR  J-STAGE 

  • Photon-Avalanche Effect of Y<sub>2</sub>O<sub>3</sub>:Er,Yb Nanoparticles Prepared by Laser Ablation in Liquid

    Onodera Yuji , Nunokawa Takashi , Odawara Osamu , Wada Hiroyuki

    … Optical properties of upconversion nanoparticles Y<sub>2</sub>O<sub>3</sub>:Er,Yb were investigated. … The upconversion nanoparticles were prepared by laser ablation in liquid, which was one of the promising plasma processes to fabricate nanoparticle-dispersed solution. … Upconversion spectra with an excitation of 980 nm were measured by fluorescence spectrophotometer. …

    Transactions of the Materials Research Society of Japan 38(2), 317-320, 2013

    J-STAGE 

  • 7PM1-A-4 Cellular nanoimagig by cathodoluminescence microscope  [in Japanese]

    Furukawa Taichi , Niioka Hirohiko , Fukushima Syoichiro , Ichimiya Masayoshi , Nagata Tomohiro , Ashida Masaaki , Miyake Jun , Araki Tsutomu , Hashimoto Mamoru

    … In addition, we propose a new correlative imaging method using upconversion (UC) fluorescence and cathodoluminescence. … The results suggest that correlative microscopy using CL, secondary electrons and fluorescence imaging could enable multi-scale investigation of molecular localization from the nanoscale to the microscale. …

    The Proceedings of the Symposium on Micro-Nano Science and Technology 2013.5(0), 271-272, 2013

    J-STAGE 

  • Calcination-Free Liftoff Photolithography of Mixed Dip-Coated Films Consisting of Rare-Earth-Ion-Doped Nanoparticles on Plastic Sheets

    Watanabe Satoshi , Hyodo Hiroshi , Taguchi Hirohisa , Soga Kohei , Takanashi Yoshifumi , Matsumoto Mutsuyoshi

    … Green and red upconversion luminescence were emitted from the RE-nanoparticles prepared from Y<sub>2</sub>O<sub>3</sub> … Near-infrared (NIR) fluorescence was also observed in the RE-1- and RE-2-nanoparticles. … The intensity ratio of the green to red upconversion luminescence was controlled by adjusting the mixing ratio of the RE-1- and RE-2-nanoparticles. …

    Journal of Oleo Science 61(10), 565-573, 2012

    J-STAGE 

  • Preparation of Lipid-Modified NaYF<SUB>4</SUB> Upconversion Fluorescence Nanoparticles  [in Japanese]

    Ishida Tomoki , Katagiri Kiyofumi , Koumoto Kunihito , Tomita Koji

    現在、蛍光ナノ粒子はバイオイメージング等の分野で応用が期待されており、さかんに研究されている。しかし、量子ドット等の蛍光ナノ粒子は、励起光である紫外光が生体組織への透過性が低く、また原料として人体に有害であるカドミウムを含んでいる点で課題も多い。これに対し、生体組織への透過性が高い近赤外光を励起光源とするアップコンバージョン(UPC)蛍光体が注目を集めている。本研究では、液相プロセスで有機溶媒中に …

    Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011S(0), 98-98, 2011

    J-STAGE 

  • Low-Temperature Flux Growth of NaYF<SUB>4</SUB>:Ln(Ln=Yb,Er,Tm) Crystals with Upconversion Fluorescence  [in Japanese]

    Wakabayashi Toshiko , Teshima Katsuya , Lee SunHyung , Oishi Shuji

    アップコンバージョン蛍光体は,励起波長よりも短い波長の光を放出する。励起光として赤外あるいは近赤外光を用いるため,特にバイオイメージングへの応用が期待されている。本研究で採用したフラックス法は,高品質な結晶をその物質の融点よりもはるかに低い温度で育成できることが特長である。我々はこれまでに,1100ºC でのNaF(あるいはKF-NaF)フラックスからNaYF<SUB>4&l …

    Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010S(0), 3L12-3L12, 2010

    J-STAGE 

  • Acceleration of guanine oxidation under visible light irradiation by photon upconversion based on triplet-triplet annihilation

    Tanaka Kazuo , Kitamura Narufumi , Inafuku Kenichi , Chujo Yoshiki

    … We report the fluorescent polymer complex which can show fluorescence emission at 380 nm with the excitation of 520 nm in aqueous media. … This photon upconversion based on triplet-triplet annihilation can efficiently take place via inter-molecular energy transfers between the Ru complex as a sensitizer and anthracene molecules as an emitter captured into the water-soluble network polymers. …

    Nucleic acids symposium series 53(1), 183-184, 2009-09

    IR 

  • Ultra-fast energy transfer process on the isolated antenna-core PSI super complex

    Yamagishi Atsushi , Ikeda Youhei , Koike Hiroyuki , Satoh Kazuhiko , Komura Masayuki , Shibata Yutaka , Itoh Shigeru

    珪藻の光化学系I(PS I)では、二種類の周辺アンテナFCP(fucoxanthin-Chl binding protein) I-1とFCP I-2がコア部分(PS I-Core)を取り巻いている。励起エネルギー移動過程を明らかにするために、珪藻<I>C. gracillis</I>から単離したFCP-PS I超複合体、PS I-Coreのみ、FCP I-1およびFCP …

    Plant and Cell Physiology Supplement 2009(0), 0044-0044, 2009

    J-STAGE 

  • Drought-induced ultra-fast Fluorescence quenching in Photosystem II in lichens studied by femto-picosecond time-resolved fluorescence spectrophotometry at cryogenic temperature

    Komura Masayuki , Miyake Hiroyuki , Yamagishi Atsushi , Shibata Yutaka , Iwasaki Ikuko , Yamamoto Yoshikazu , Itoh Shigeru

    地衣類は菌類と藻類が共生して光独立栄養的に生育し、極度の乾燥環境でも生存可能である。乾燥時には光化学系II(PSII)が吸収した光エネルギーはただちに消光され、阻害を防ぐと考えられてきた。最近、740 nmに蛍光を示すクロロフィル(Chl740)が緑藻<I>Trebouxia</I>を共生する地衣類のPSII内部で消光分子として機能すると提唱された[1]。我々は乾燥地衣類生 …

    Plant and Cell Physiology Supplement 2009(0), 0578-0578, 2009

    J-STAGE 

  • Blue up-conversion fluorescence properties of Tm, Yb codoped novel TeO<sub>2</sub>-based glass  [in Japanese]

    Hayakawa Tomokatsu , Niimi Haruo , Nogami Masayuki , Thomas Philippe

    Tm, Ybを共添加した新規TeO2系ガラスの青色アップコンバージョン蛍光について報告する。そのパワー依存性から、Ybライフタイムの測定結果, エネルギー移動確率の評価結果について議論する。

    Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009F(0), 2O06-2O06, 2009

    J-STAGE 

  • Environmentally friendly growth of functional nanocrystals with upconversion fluorescence  [in Japanese]

    Teshima Katsuya

    … and NaYF<sub>4</sub>:Ln (Ln=Yb, Er, Tm) crystals with upconversion fluorescence were successfully grown by the cooling of the solo NaF at a growth temperature of 1100 ℃. … In addition, the upconversion fluorescence property of the grown NaYF<sub>4</sub>:Ln crystals was also dependent on the cooling rate, that is, the crystal system, and type of dopant. …

    Hosokawa Powder Technology Foundation ANNUAL REPORT 17(0), 61-66, 2009

    J-STAGE 

  • Fabrication of rare-earth-doped LaOCl nanophosphors by using spray dryer  [in Japanese]

    Konishi Tomoya

    … <p>Fluorescence bioimaging is a technique to visualize biological phenomena both in vivo and in vitro by specific adsorption of fluorescence probes to target organic tissues. … One of the most serious problems in the fluorescence bioimaging is the limitation of observation time due to color-fading of the organic fluorescence probes and damages on the bio system, both of which are caused by the excitation of ultraviolet irradiation. …

    Hosokawa Powder Technology Foundation ANNUAL REPORT 17(0), 91-96, 2009

    J-STAGE 

  • Fluorescence bioimaging under near infrared excitation using upconversion in rare-earth-doped ceramic nanophosphors  [in Japanese]

    SOGA Kohei , KAMIMURA Masao , NAGASAKI Yukio

    <p>蛍光バイオイメージングは医療や生命科学における重要技術である.しかし,現在の蛍光バイオイメージングでは,励起光として用いる短波長光による蛍光体の退色や生体へのダメージ,強い光散乱により長時間の深度が深いイメージングが困難である.一方,希土類イオンを含有するセラミックスナノ粒子は,近赤外光を励起光としたさまざまな発光を示すことが知られている.本稿では,波長の長い近赤外光を励起光とし …

    Oyo Buturi 77(12), 1458-1461, 2008-12-10

    J-STAGE  References (14) Cited by (2)

  • 1 / 3
Page Top