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Journal Articles

Incorporation of U, Pb and rare earth elements in calcite through crystallisation from amorphous calcium carbonate; Simple preparation of reference materials for microanalysis

Miyajima, Yusuke*; Saito, Ayaka*; Kagi, Hiroyuki*; Yokoyama, Tatsunori; Takahashi, Yoshio*; Hirata, Takafumi*

Geostandards and Geoanalytical Research, 45(1), p.189 - 205, 2021/03

 Times Cited Count:0 Percentile:0.01(Geochemistry & Geophysics)

Uncertainty for elemental and isotopic analyses of calcite by LA-ICP-MS is largely controlled by the homogeneity of the reference materials (RMs) used for normalization and validation. In order to produce calcite RMs with homogeneous elemental and isotopic compositions, we incorporated elements including U, Pb, and rare earth elements into calcite through heat- and pressure-induced crystallization from amorphous calcium carbonate that was precipitated from element-doped reagent solution. X-ray absorption spectra showed that U was present as U(VI) in the synthesized calcite, probably with a different local structure from that of aqueous uranyl ions. The uptake rate of U by our calcite was higher in comparison to synthetic calcite of previous studies. Variations of element mass fractions in the calcite were better than 12% 2RSD, mostly within 7%. The $$^{207}$$Pb/$$^{206}$$Pb ratio in the calcite showed $$<$$1% variations, while the $$^{238}$$U/$$^{206}$$Pb ratio showed 3-24% variations depending on element mass fractions. Using the synthetic calcite as primary RMs, we could date a natural calcite RM, WC-1, with analytical uncertainty as low as $$<$$3%. The method presented can be useful to produce calcite with controlled and homogeneous element mass fractions, and is a promising alternative to natural calcite RMs for U-Pb geochronology.

Journal Articles

Potential for remote controllable systematization of the method of testing reinforced concrete using guided-wave on rebar

Furusawa, Akinori; Nishimura, Akihiko; Takenaka, Yusuke; Muramatsu, Toshiharu

Proceedings of International Topical Workshop on Fukushima Decommissioning Research (FDR 2019) (Internet), 4 Pages, 2019/05

The aim of this work presented here is to demonstrate the potential of our method for remote controllable systematization, of testing reinforced concrete based on ultrasonic guided-wave on rebar. In order to investigate how the deteriorated phenomena has the effects on the ultrasonic guided-wave propagating on the rebar, following experiments are conducted. Test pieces used for the experiments are made of bare steel rod and cylindrically pored mortar to be representing the actual reinforced concrete. Irradiating the end face of the rod with nanosecond pulsed laser makes the ultrasonic guided-wave induced, at the other end face, the guided wave signal is measured with ultrasonic receiver. One test piece is with no damage and the other is deteriorated test piece. The deterioration is made by electrolytic corroded method. The guided-wave signal from the deteriorated test piece is measured with respect to each energization time, the change in the waveform is investigated. Analyzing the results from the experiments above, it is found that the deterioration of rebar has remarkable effects on the guided-wave signal. The signal from test piece with no damage has strong peak at both specific frequency and lower region, on the other hand, signals from deteriorated test piece has only at the specific frequency depending on the diameter of the steel rod. Finally, discussion concerning with the experimental results and future perspective for remote controllable systematization of our method is carried out.

Journal Articles

Laser-induced breakdown spectroscopy and related resonance spectroscopy for nuclear fuel cycle management and for decommissioning of "Fukushima Daiichi Nuclear Power Station"

Wakaida, Ikuo; Oba, Hironori; Miyabe, Masabumi; Akaoka, Katsuaki; Oba, Masaki; Tamura, Koji; Saeki, Morihisa

Kogaku, 48(1), p.13 - 20, 2019/01

By Laser Induced Breakdown Spectroscopy and by related resonance spectroscopy, elemental and isotope analysis of Uranium and Plutonium for nuclear fuel materials and in-situ remote analysis under strong radiation condition for melt downed nuclear fuel debris at damaged core in "Fukushima Daiichi Nuclear Power Station", are introduced and performed as one of the application in atomic energy research field.

Journal Articles

Improvement in quantitative performance of underwater laser-induced breakdown spectroscopy based on the understanding of laser ablation phenomena

Matsumoto, Ayumu

Reza Kako Gakkai-Shi, 23(3), p.222 - 231, 2016/10

no abstracts in English

Journal Articles

Effect of defocusing on laser ablation plume observed by laser-induced fluorescence imaging spectroscopy

Oba, Masaki; Miyabe, Masabumi; Akaoka, Katsuaki; Wakaida, Ikuo

Japanese Journal of Applied Physics, 55(2), p.022401_1 - 022401_4, 2016/02

 Times Cited Count:2 Percentile:12.91(Physics, Applied)

We used laser-induced fluorescence imaging with a varying beam focal point to observe ablation plumes from metal and oxide samples of gadolinium. The plumes expand vertically when the focal point is far from the sample surface. In contrast, the plume becomes hemispherical when the focal point is on the sample surface. In addition, the internal plume structure and the composition of the ablated atomic and ionic particles also vary significantly. The fluorescence intensity of a plume from a metal sample is greater than that from an oxide sample, which suggests that the number of monatomic species produced in each plume differs. For both the metal and oxide samples, the most intense fluorescence from atomic (ionic) species is observed with the beam focal point at 3-4 mm (2 mm) from the sample surface.

JAEA Reports

Proceedings of the 15th Symposium on Advanced Photon Research; November 13-14, 2014, Kizugawa, Kyoto, Japan

Secretariat of Symposium on Advanced Photon Research

JAEA-Conf 2015-001, 93 Pages, 2015/07

JAEA-Conf-2015-001.pdf:27.43MB

The 15th Symposium on Advanced Photon Research was held at Kansai Photon Science Institute, Japan Atomic Energy Agency (JAEA-KPSI) in Kizugawa city, Kyoto on November 13 - 14, 2014. This report consists of invited and contributed papers presented at the oral and poster sessions in the Symposium.

Journal Articles

Hydrodynamics driven by ultrashort laser pulse; Simulations and the optical pump - X-ray probe experiment

Inogamov, N. A.*; Zhakhovsky, V. V.*; Hasegawa, Noboru; Nishikino, Masaharu; Yamagiwa, Mitsuru; Ishino, Masahiko; Agranat, M. B.*; Ashitkov, S. I.*; Faenov, A. Y.*; Khokhlov, V. A.*; et al.

Applied Physics B, 119(3), p.413 - 419, 2015/06

 Times Cited Count:6 Percentile:40.44(Optics)

Journal Articles

Formation of fullerene(C$$_{60}$$) by laser ablation in superfluid helium at 1.5K

Aratono, Yasuyuki; Wada, Akira*; Akiyama, Kazuhiko; Kitazawa, Shinichi; Hojo, Kiichi; Naramoto, Hiroshi*

Chemical Physics Letters, 408(4-6), p.247 - 251, 2005/06

 Times Cited Count:1 Percentile:3.19(Chemistry, Physical)

C$$_{60}$$ fulleren was detected in the deposit produced by the laser ablation in superfluid helium at 1.5K. From the mass spectrometry, it was found that the ratio, $$^{12}$$C$$_{60}$$/$$^{12}$$C$$_{59}$$$$^{13}$$C, differs from statistical one calculated by Poisson distribution for natural graphite. Assuming the recombination of atomic carbons to C$$_{2}$$ molecules as an initial stage for C$$_{60}$$ formation, the different isotopic ratio of C$$_{60}$$ from Poisson statistics was ascribed to the tunneling recombination between $$^{12}$$C and $$^{13}$$C atoms in the bubble state.

Journal Articles

Diagnostics of pulsed plasma in laser ablation of boron compounds

Oba, Hironori; Saeki, Morihisa; Yokoyama, Atsushi

Proceedings of Plasma Science Symposium 2005/22nd Symposium on Plasma Processing (PSS-2005/SPP-22), p.331 - 332, 2005/01

A plasma produced by a XeCl laser ablation of boron compound was investigated using ion probes and a quadrupole mass spectrometer. Although the ablated neutral boron atoms had a natural abundance ratio, the isotope ratio of singly ionized boron atoms having a greatly different from the natural abundance ratio was observed. The observed isotope ratio of boron ions was different from the natural abundance.

Journal Articles

Numerical simulation of melting and evaporation of a cold foil target irradiated by a pre-pulse

Utsumi, Takayuki*; Matsukado, Koji*; Daido, Hiroyuki; Esirkepov, T. Z.; Bulanov, S. V.*

Applied Physics A, 79(4-6), p.1185 - 1187, 2004/09

 Times Cited Count:9 Percentile:35.78(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Preparation of TiO$$_{2}$$ nanoparticles by pulsed laser ablation; Ambient pressure dependence of crystallization

Matsubara, Masakazu*; Yamaki, Tetsuya; Ito, Hisayoshi; Abe, Hiroaki*; Asai, Keisuke*

Japanese Journal of Applied Physics, Part 2, 42(5A), p.L479 - L481, 2003/05

Pulsed laser ablation with a KrF excimer laser was used to prepare fine particles of titanium dioxide (TiO$$_{2}$$). The ablation in an atmosphere of Ar and O$$_{2}$$ (5:5) at total pressures of $$geq$$ 1 Torr led to the formation of TiO$$_{2}$$ nanoparticles composed of anatase and rutile structures without any suboxides. The weight fraction of the rutile/anatase crystalline phases was controlled by the pressure of the Ar/O$$_{2}$$ gas. The TiO$$_{2}$$ nanoparticles had a spherical shape and their size, ranging from 10 and 14 nm, also appeared to be dependent on the ambient pressure.

JAEA Reports

Conceptual design of cesium removal device for ITER NBI maintenance

Oka, Kiyoshi; Shibanuma, Kiyoshi

JAERI-Tech 2003-004, 57 Pages, 2003/03

JAERI-Tech-2003-004.pdf:2.36MB

Cesium is required in order to generate a stable negative ion of hydrogen in an ion source of the neutral beam injector (NBI), which is one of the plasma-heating devices for International Thermonuclear Experimental Reactor (ITER). After long time operation of NBI, the cesium deposits to the insulators supporting the electrode. Due to the deterioration of the insulation resistance, the continuous operation of the NBI will be difficult. In addition, the NBI device is activated by neutron from D-T plasma, so that a periodic removal and cleaning of the cesium on the insulators by remote handling is required. A study of the cesium removal scenario and device is therefore required considering remote handling. In this report, a cesium removal procedure and conceptual design of the cesium removal device using laser ablation technique are studied, and the feasibility of laser ablation is shown.

Journal Articles

High-quality epitaxial TiO$$_{2}$$ thin films grown on $$alpha$$-Al$$_{2}$$O$$_{3}$$ substrates by pulsed laser deposition

Shinohara, Ryuji*; Yamaki, Tetsuya; Yamamoto, Shunya; Ito, Hisayoshi; Asai, Keisuke*

Journal of Materials Science Letters, 21(12), p.967 - 969, 2002/06

 Times Cited Count:9 Percentile:38.24(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Effects of annealing and quenching treatments on reconstruction of rutile thin films on sapphire substrates

Choi, Y.; Yamamoto, Shunya; Abe, Hiroaki; Ito, Hisayoshi

Surface Science, 499(2-3), p.203 - 209, 2002/03

 Times Cited Count:13 Percentile:56.86(Chemistry, Physical)

Morphology change in rutile TiO2 thin films on sapphire substrate prepared by pulsed laser deposition under reduced oxygen envirnment was investigated as a function of film thickness, temperature and cooling treatment with AFM, XRD, and SEM/EDX. In case of 5 nm thick films, morphology strongly deponds on annealing and cooling treatments. Formation model of TiO2 particles on sapphire substrate is proposed based on instability of the substrate at elevated temperature.

Journal Articles

Removal of metal-oxide layers formed on stainless and carbon steel surfaces by excimer laser irradiation in various atmospheres

Kameo, Yutaka; Nakashima, Mikio; Hirabayashi, Takakuni*

Nuclear Technology, 137(2), p.139 - 146, 2002/02

 Times Cited Count:6 Percentile:41.16(Nuclear Science & Technology)

In order to apply laser ablation technique for decontamination of metal wastes contaminated with radioactive nuclides, the effect of irradiation atmospheres on removal of oxide layers on steel surfaces by laser ablation was studied. Based on the assumption that the absorption of laser light follows the Lambert-Beer law, ablation parameters, such as absorption length and threshold fluence for ablation, of sintered Fe$$_{2}$$O$$_{3}$$ and stainless and carbon steels were measured in He, O$$_{2}$$, Kr or SF$$_{6}$$ atmosphere. The results indicated that SF$$_{6}$$ was the most effective gas of all irradiation atmospheres studied for the exclusive removal of oxide layers formed on stainless and carbon steel samples in high temperature pressurized water. Secondary ion mass spectroscopic measurement and scanning electron microscopic observation confirmed that no oxide layer existed on the steel samples after the exclusive removal with laser irradiation.

Journal Articles

Structure of hyperlithiated Li$$_{3}$$O and evidence for electronomers

Yokoyama, Keiichi; Tanaka, Hiromasa*; Kudo, Hiroshi*

Journal of Physical Chemistry A, 105(17), p.4312 - 4315, 2001/04

 Times Cited Count:20 Percentile:55.41(Chemistry, Physical)

no abstracts in English

Journal Articles

Preparation of TiO$$_{2}$$-anatase film on Si(001) substrate with TiN and SrTiO$$_{3}$$ as buffer layers

Sugiharuto; Yamamoto, Shunya; Sumita, Taishi; Miyashita, Atsumi

Journal of Physics; Condensed Matter, 13(13), p.2875 - 2881, 2001/04

 Times Cited Count:14 Percentile:61.06(Physics, Condensed Matter)

An epitaxial TiO$$_{2}$$-anatase thin film was grown on the Si(001) substrate with SrTiO$$_{3}$$/TiN as the buffer layers by pulsed laser deposition technique under an oxygen gas supply. The characterization of the epitaxial TiO$$_{2}$$-anatase film was performed using the X-ray diffraction method. The crystallographic relationships between the TiO$$_{2}$$-anatase film and SrTiO$$_{3}$$/TiN buffer layers were analyzed by the $$theta$$-2$$theta$$ scan and pole figure measurement. The growth direction of the films was determined as $$rm TiO_{2}langle 001rangle$$ / $$rm SrTiO_{3}langle 001rangle$$ / $$rm TiNlangle 001rangle$$ / $$rm Silangle 001rangle$$ and their in-plane relationship $$rm TiO_{2}{110}$$ // $$rm SrTiO_{3}{100}$$ // $$rm TiN{100}$$ // $$rm Si{100}$$. The crystalline quality of TiO$$_{2}$$-anatase was examined by the rocking curve analysis. The composition of the thin film packaging was characterized by Rutherford backscattering spectrometry (RBS) using 2.0 MeV $$^{4}$$He beam.

Journal Articles

Production of hyperlithiated Li$$_{2}$$F by a laser albation of LiF-Li$$_{3}$$N mixture

Yokoyama, Keiichi; Haketa, Naoki*; Hashimoto, Masashi; Furukawa, Katsutoshi; Tanaka, Hiromasa*; Kudo, Hiroshi*

Chemical Physics Letters, 320(5-6), p.645 - 650, 2000/04

 Times Cited Count:33 Percentile:71.13(Chemistry, Physical)

no abstracts in English

Journal Articles

Structural, optical and electrical properties of laser deposited FeTiO$$_{3}$$ films on C- and A-cut sapphire substrates

Dai, Z.*; Naramoto, Hiroshi; Narumi, Kazumasa; Yamamoto, Shunya; Miyashita, Atsumi

Journal of Applied Physics, 85(10), p.7433 - 7437, 1999/05

 Times Cited Count:21 Percentile:67.64(Physics, Applied)

no abstracts in English

Journal Articles

Single pulse nm-size grating formation in polymers using laser ablation with an irradiation wavelength of 355nm

Lippert, T.*; Gerber, T.*; Wokaun, A.*; Funk, D. J.*; Fukumura, H.; Goto, Masahiro

Applied Physics Letters, 75(7), p.1018 - 1020, 1999/00

 Times Cited Count:38 Percentile:81.7(Physics, Applied)

no abstracts in English

40 (Records 1-20 displayed on this page)