Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 37

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Measurement of cesium isotopic ratio by thermal ionization mass spectrometry for neutron capture reaction studies on $$^{135}$$Cs

Shibahara, Yuji*; Nakamura, Shoji; Uehara, Akihiro*; Fujii, Toshiyuki*; Fukutani, Satoshi*; Kimura, Atsushi; Iwamoto, Osamu

Journal of Radioanalytical and Nuclear Chemistry, 325(1), p.155 - 165, 2020/07

 Times Cited Count:0 Percentile:100(Chemistry, Analytical)

The measurements of isotopic ratios of Cs samples by thermal ionization mass spectrometry were performed for the analysis of their samples used to evaluate nuclear data obtained for $$^{135}$$Cs. To obtain a high intensity and stable ion beam, the effects of additive agents on the ionization of Cs were examined. The effect of silicotungstic acid on the ionization of Cs was the largest among the additive agents studied in the present study, while the silicotungstic acid also showed the largest isobaric interference of polyatomic ions. It was demonstrated that as small as 2$$times$$10$$^{-13}$$ g of a Cs sample was sufficient to achieve the analytical precision required to measure the $$^{135}$$Cs/$$^{137}$$Cs ratio in the case where an additive agent of TaO/glucose was employed. After examining of the analytical conditions, such as the interference effect due to Ba, the measurements of the isotopic ratios of two Cs samples used in our study using TIMS were conducted, and it was discussed how much the ratios contributed to evaluation of the neutron capture cross-section of $$^{135}$$Cs.

Journal Articles

Vertical distributions of Iodine-129 and iodide in the Chukchi Sea and Bering Sea

Miwa, Kazuji; Obata, Hajime*; Suzuki, Takashi

Journal of Nuclear Science and Technology, 57(5), p.537 - 545, 2020/05

 Times Cited Count:1 Percentile:58.8(Nuclear Science & Technology)

This study investigated the vertical distribution of Iodine-129 ($$^{129}$$I) which is mainly produced by European nuclear reprocessing plants in the Chukchi Sea and Bering Sea. $$^{129}$$I was found to be distributed almost uniformly in fallout level, and an increasing in $$^{129}$$I concentration levels caused by high $$^{129}$$I water inflow from the Atlantic Ocean was not observed. Additionally, we revealed the vertical distribution of iodide, one chemical form of iodine, from the Bering Shelf area to the Chukchi Sea for the first time. The increasing tendency of iodide near sea bottom was observed.

Journal Articles

Measurements of thermal-neutron capture cross-section of cesium-135 by applying mass spectrometry

Nakamura, Shoji; Shibahara, Yuji*; Kimura, Atsushi; Iwamoto, Osamu; Uehara, Akihiro*; Fujii, Toshiyuki*

Journal of Nuclear Science and Technology, 57(4), p.388 - 400, 2020/04

 Times Cited Count:1 Percentile:58.8(Nuclear Science & Technology)

The thermal-neutron capture cross-section ($$sigma_{0}$$) and resonance integral(I$$_{0}$$) were measured for the $$^{135}$$Cs(n,$$gamma$$)$$^{136}$$Cs reaction by an activation method and mass spectrometry. We used $$^{135}$$Cs contained as an impurity in a normally available $$^{137}$$Cs standard solution. An isotope ratio of $$^{135}$$Cs and $$^{137}$$Cs in a standard $$^{137}$$Cs solution was measured by mass spectrometry to quantify $$^{135}$$Cs. The analyzed $$^{137}$$Cs samples were irradiated at the hydraulic conveyer of the research reactor in Institute for Integral Radiation and Nuclear Science, Kyoto University. Wires of Co/Al and Au/Al alloys were used as neutron monitors to measure thermal-neutron fluxes and epi-thermal Westcott's indices at an irradiation position. A gadolinium filter was used to measure the $$sigma_{0}$$, and a value of 0.133 eV was taken as the cut-off energy. Gamma-ray spectroscopy was used to measure induced activities of $$^{137}$$Cs, $$^{136}$$Cs and monitor wires. On the basis of Westcott's convention, the $$sigma_{0}$$ and I$$_{0}$$ values were derived as 8.57$$pm$$0.25 barn, and 45.3$$pm$$3.2 barn, respectively. The $$sigma_{0}$$ obtained in the present study agreed within the limits of uncertainties with the past reported value of 8.3$$pm$$0.3 barn.

Journal Articles

Activation measurement for thermal-neutron capture cross-section of Cesium-135

Nakamura, Shoji; Kimura, Atsushi; Iwamoto, Osamu; Shibahara, Yuji*; Uehara, Akihiro*; Fujii, Toshiyuki*

KURNS Progress Report 2018, P. 106, 2019/08

Under the ImPACT project, the neutron capture cross-section measurements of Cesium-135 ($$^{135}$$Cs) among the long-lived fission products have been performed at Kyoto University. This paper reports measurements of the thermal-neutron capture cross-section of $$^{135}$$Cs at the Kyoto University Research Reactor (KUR).

Journal Articles

Ion desorption from bulk cesium chloride at moderate temperature ($$<$$500$$^{circ}$$C) under electric field

Baba, Yuji; Shimoyama, Iwao

e-Journal of Surface Science and Nanotechnology (Internet), 16, p.53 - 59, 2018/03

Surface ionization for cesium chloride and Cs-adsorbed soil has been investigated. For cesium chloride, neutral cesium was desorbed around 645$$^{circ}$$C which is close to the melting point of cesium. While Cs$$^{+}$$ ion was desorbed from 400$$^{circ}$$C. The ratio of desorbed ions and neutrals (Cs$$^{+}$$/Cs$$^{0}$$) has a maximum around 410 $$^{circ}$$C. Temperature dependence of Cs$$^{+}$$/Cs$$^{0}$$ was analyzed using Saha-Langmuir equation, As a result, it was found that the temperature maximum is due to the changes of the surface work function induced by the phase transition of CsCl.

Journal Articles

Inductively coupled plasma-mass spectrometry

Esaka, Fumitaka

Analytical Sciences, 33(10), p.1097 - 1098, 2017/10

 Times Cited Count:2 Percentile:22.41(Chemistry, Analytical)

Inductively coupled plasma-mass spectrometry (ICP-MS) is widely used in various fields such as environmental, geological, and clinical sciences. In this report, recent advances of the ICP-MS analysis and expected applications are described.

Journal Articles

High precision analysis of isotopic composition for samples used for nuclear cross-section measurements

Shibahara, Yuji*; Hori, Junichi*; Takamiya, Koichi*; Fujii, Toshiyuki*; Fukutani, Satoshi*; Sano, Tadafumi*; Harada, Hideo

EPJ Web of Conferences, 146, p.03028_1 - 03028_4, 2017/09

 Times Cited Count:0 Percentile:100

Journal Articles

Application of automated particle screening for effective analysis of individual uranium particles by thermal ionization mass spectrometry

Esaka, Fumitaka; Suzuki, Daisuke; Yomogida, Takumi; Magara, Masaaki

Analytical Methods, 8(7), p.1543 - 1548, 2016/02

AA2015-0572.pdf:0.66MB

 Times Cited Count:6 Percentile:42.47(Chemistry, Analytical)

The isotope ratio analysis of individual uranium particles in environmental samples taken at nuclear facilities is important to clarify their origins for nuclear safeguards. In the present study, automated particle screening was used to select uranium particles prior to precise isotope ratio analysis by thermal ionization mass spectrometry (TIMS). As a result, molecular ion interferences on the uranium mass region were able to be almost completely avoided in the analysis of real inspection samples using APM-TIMS. Therefore, the performance of APM-TIMS was sufficient for obtaining isotope ratio data of individual particles without molecular ion interferences.

Journal Articles

Transmission secondary ion mass spectrometry using 5 MeV C$$_{60}$$$$^{+}$$ ions

Nakajima, Kaoru*; Nagano, Kengo*; Suzuki, Motofumi*; Narumi, Kazumasa; Saito, Yuichi; Hirata, Koichi*; Kimura, Kenji*

Applied Physics Letters, 104(11), p.114103_1 - 114103_4, 2014/03

 Times Cited Count:5 Percentile:70.65(Physics, Applied)

Journal Articles

Mass-spectrometric study of PuCd$$_{2}$$

Nakajima, Kunihisa; Arai, Yasuo; Yamashita, Toshiyuki

Journal of Physics and Chemistry of Solids, 66(2-4), p.639 - 642, 2005/02

 Times Cited Count:2 Percentile:86.56(Chemistry, Multidisciplinary)

PuCd$$_{2}$$ intermetallic compound was prepared by heating pure Pu and Cd metals at about 950K. PuCd$$_{2}$$ was found to be a prototype of CdI$$_{2}$$ by means of powder X-ray diffractometry. Mass-spectrometric experiment was performed in the temperature range of 650-770K. It was found that the vapor pressures of Cd over PuCd$$_{2}$$+Pu were three to five orders of magnitude lower than those over Cd in this temperature range. From these vapor pressures, Gibbs free energy of formation of PuCd$$_{2}$$ was evaluated.

JAEA Reports

Development of frequency stabilized laser system for long-lived isotope analysis, 2; Simultaneous locking system for multiple diode lasers using Zeeman effect and interferometer

Miyabe, Masabumi; Kato, Masaaki; Oba, Masaki; Wakaida, Ikuo; Watanabe, Kazuo

JAERI-Tech 2004-065, 19 Pages, 2004/10

JAERI-Tech-2004-065.pdf:0.99MB

In nuclear waste materials there are various radionuclides to which standard analytical techniques are difficult to be applied. We are developing an analytical technique where such nuclides are ionized and mass-analyzed using diode laser based multi-step RIMS technique. The diode laser, however, has one drawback, i.e. its oscillation wavelength is readily drifted by acoustic, electric and optical noise, and thus the laser without frequency stabilization is not suitable for the analysis. In this study, we have developed (1) the diode laser whose frequency is stabilized to an intense absorption line of Rb by Zeeman effect and (2) the stabilization system where diode lasers for 3-step ionization of Ca are locked to the Rb-stabilized laser using a Fabry-perot interferometer. Additionally, to evaluate overall frequency stability of the stabilization system, fluctuations in the photoion and fluorescence signals arising from 3-step RIMS of Ca were simultaneously observed.

JAEA Reports

Development of frequency stabilized laser system for long-lived isotope analysis, 1; Development of Littrow configuration extended cavity diode laser

Miyabe, Masabumi; Oda, Koichi*; Oba, Masaki; Kato, Masaaki; Wakaida, Ikuo; Watanabe, Kazuo

JAERI-Tech 2004-064, 33 Pages, 2004/10

JAERI-Tech-2004-064.pdf:1.89MB

In nuclear waste materials there are various radionuclides to which standard analytical techniques are difficult to be applied. We are developing an analytical technique where such nuclides are analyzed using multi-step resonance ionization mass spectrometry. In this study, we have developed an external cavity diode laser applicable to the analysis. The wavelength and output power dependence on injection current and temperature were investigated for various types of laser diodes. Based on the data, we have obtained a suitable condition to operate the ECDL in stable single-mode oscillation, so that a continuous scanning range of about 100 GHz was realized. Additionaly, to evaluate the bandwidth of the developed ECDL, we have performed Doppler-free spectroscopy. The reasonable agreement of the measured isotope shift and HFS splitting with the reported values demonstrated that the developed ECDL is applicable to a precise laser spectroscopy as well as a laser trace analysis.

Journal Articles

Photon stimulated desorption (PSD)

Baba, Yuji

Hyomen Kagaku No Kiso To Oyo, p.751 - 755, 2004/06

no abstracts in English

Journal Articles

Coexistence of passive and active oxidation for O$$_{2}$$/Si(001) system observed by SiO mass spectrometry and synchrotron radiation photoemission spectroscopy

Teraoka, Yuden; Moritani, Kosuke; Yoshigoe, Akitaka

Applied Surface Science, 216(1-4), p.8 - 14, 2003/06

 Times Cited Count:6 Percentile:62.81(Chemistry, Physical)

The experiments concerning the oxidation of Si(001) were performed at the surface reaction analysis apparatus, installed at the beamline BL23SU in the SPring-8. The SiO desorb remarkably at surface temperature of 1000 K. The desorption yield increased with increasing the incident energy of O$$_{2}$$. On the other hand, the desorption yield increased with decreasing the incident energy in the temperature region lower than 1000 K. Oxygen uptake curves observed by O-1s photoemission measurements corresponded to the SiO desorption features. These facts reveal that the passive oxidation coexists with the SiO desorption in the temperature region from 900 K to 1000 K.

Journal Articles

Investigation of vaporization behavior of hyper-stoichiometric uranium dioxide by Knudsen effusion mass spectrometry

Nakajima, Kunihisa; Arai, Yasuo

Journal of Nuclear Materials, 317(2-3), p.243 - 251, 2003/05

 Times Cited Count:3 Percentile:72.76(Materials Science, Multidisciplinary)

The Knudsen effusion mass-spectrometric measurement of pure UO$$_{2+x}$$(s) are carried out at 1673, 1773 and 1873K to evaluate $$Delta$$G$$_{f}$$$$^{circ}$$(UO$$_{3}$$,g) as well as to measure the partial pressures of UO$$_{3}$$(g) and O$$_{2}$$(g) over UO$$_{2+x}$$(s) as function of the O/U ratio. It was found that the partial pressures of O$$_{2}$$(g) over UO$$_{2+x}$$(s) almost agree with the experimental data reported in the past and the values derived from the empirical equation given by Nakamura and Fujino. Further, it was found that the values of $$Delta$$G$$_{f}$$$$^{circ}$$(UO$$_{3}$$,g) obtained in this study are in good agreement with the recommended values.

Journal Articles

Mass-spectrometric determination of oxygen potential of hypostoichiometric urania-yttria solid solution

Nakajima, Kunihisa; Omichi, Toshihiko*; Arai, Yasuo

Journal of Nuclear Materials, 304(2-3), p.176 - 181, 2002/08

 Times Cited Count:3 Percentile:75.07(Materials Science, Multidisciplinary)

The oxygen potentials of two type urania-yttria solid solutions, one is the solid solution expressed as nearly U$$_{1-y}$$Y$$_{y}$$O$$_{2-y/2}$$ and the other is nearly stoichiometric solid solution, are investigated by use of a mass spectrometer combined with a Knudsen cell. The oxygen potentials for the nearly stoichiometric specimens are much higher than those for pure urania with similar stoichiometry. On the other hand, the oxygen potentials for fully reduced specimens almost agree with those for pure urania having the same oxygen deficiencis.

Journal Articles

Structures and bonding of hyperlithiated molecules

Kudo, Hiroshi*; Yokoyama, Keiichi

Bulletin of the Chemical Society of Japan, 69(6), p.1459 - 1469, 1996/00

 Times Cited Count:19 Percentile:30.83(Chemistry, Multidisciplinary)

no abstracts in English

Journal Articles

Note on the variation of isotopic abundance ratios of metallic lithium during vacuum evaporation-condensation process

Shinohara, Nobuo; *

Nuclear Instruments and Methods in Physics Research A, 362, p.114 - 116, 1995/00

 Times Cited Count:0 Percentile:100(Instruments & Instrumentation)

no abstracts in English

Journal Articles

Studies on chemical thermodynamics of hyperlithiated molecules by Knudsen-effusion mass spectrometry

Kudo, Hiroshi

Shitsuryo Bunseki, 41(6), p.317 - 328, 1993/00

no abstracts in English

Journal Articles

Observation of hypervalent CLi$$_{6}$$ by Knudsen-effusion mass spectrometry

Kudo, Hiroshi

Nature, 355(6359), p.432 - 434, 1992/01

 Times Cited Count:115 Percentile:3.11(Multidisciplinary Sciences)

no abstracts in English

37 (Records 1-20 displayed on this page)