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JAEA Reports

Structural investigation of simulated waste glass samples by using XAFS measurement in soft X-ray region (Joint research)

Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Ota, Toshiaki*; Kojima, Kazuo*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*

JAEA-Research 2020-009, 48 Pages, 2020/09

JAEA-Research-2020-009.pdf:4.67MB

The local structure of glass-forming elements and waste elements in waste glass varies with its chemical composition. In this study, borosilicate glass frit and simulated waste glass samples were prepared and the local structure and chemical state regarding boron (B), oxygen (O), and waste elements of cerium (Ce), cesium (Cs) were estimated by using XAFS measurement in soft X-ray region. Following results were obtained by XAFS measurements of prepared glass frit and simulated waste glass samples: (1) The existence ratio of four coordinate sp$$^{3}$$ structure (BO$$_{4}$$) tends to increase with increasing Na$$_{2}$$O content in glass samples. (2) The height of a pre-edge which appears by K-edge XANES spectrum of O is so high that the Fe content in glass samples. Following results were obtained by XAFS measurements of simulated waste glass samples after immersion test to investigate long chemical stability. (1) The existence ratio of four coordinate sp$$^{3}$$ structure (BO$$_{4}$$) increases by immersion test. (2) Ce which exists in the surface layer is oxidized by immersion test, and much of Cs in surface layer is lost after leach testing. Even if the glass frit form (fiber cartridge or beads) and manufacturing method were changed and a glass sample of the similar chemical composition was prepared, these observed Raman spectra of samples were different.

Journal Articles

Investigation of chemical state of simulated waste glasses by using XAFS measurement

Nagai, Takayuki; Shimoyama, Iwao; Okamoto, Yoshihiro; Akiyama, Daisuke*; Arima, Tatsumi*

Photon Factory Activity Report 2019 (Internet), 3 Pages, 2020/00

no abstracts in English

JAEA Reports

XAFS measurement of simulated waste glass samples (Joint research)

Nagai, Takayuki; Sasage, Kenichi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamagishi, Hirona*; Ota, Toshiaki*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*; Takahashi, Tomoe*; et al.

JAEA-Research 2019-003, 94 Pages, 2019/09

JAEA-Research-2019-003.pdf:7.92MB

The local structures of glass-forming elements and waste elements would change by the chemical composition of waste glass including those elements. In this study, simulated waste glass samples were prepared from borosilicate glass frit including phosphorus (P) or vanadium (V), and we investigated local structures of boron, sodium, and waste elements in these P glass and V glass samples by using synchrotron XAFS measurements in soft and hard X ray region.

JAEA Reports

XAFS measurement of simulated waste glass samples prepared from borosilicate glass frit including phosphorus pentaoxide (Joint research)

Nagai, Takayuki; Kobayashi, Hidekazu; Shimamura, Keisuke; Oyama, Koichi; Sasage, Kenichi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamanaka, Keisuke*; Ota, Toshiaki*

JAEA-Research 2018-005, 72 Pages, 2018/09

JAEA-Research-2018-005.pdf:28.2MB

Addition of radioactive waste to a borosilicate glass frit affects the local structures of glass-forming elements and waste elements in a waste glass produced in a vitrification process. In this study, simulated waste glass samples were prepared from borosilicate glass frit including phosphorus pentaoxide, and we investigated local structures of sodium (Na), boron (B), and waste elements in these glass samples by using synchrotron XAFS measurements in soft and hard X ray region.

JAEA Reports

XAFS measurement of simulated waste borosilicate glass samples (Joint research)

Nagai, Takayuki; Kobayashi, Hidekazu; Sasage, Kenichi; Ayame, Yasuo; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamanaka, Keisuke*; Ota, Toshiaki*

JAEA-Research 2017-005, 54 Pages, 2017/06

JAEA-Research-2017-005.pdf:16.17MB

Addition of radioactive waste to a borosilicate frit affects the local structures of boron (B) and waste elements in a waste glass. Synchrotron XAFS measurement was applied to investigate the local structural changes by using simulated waste borosilicate glass samples. Following results were obtained by the B K-edge XAFS analysis. It was confirmed that B K-edge XAFS analysis enables us to discriminate sp$$^{2}$$ type boron (BO$$_{3}$$) from sp$$^{3}$$ type boron (BO$$_{4}$$). Addition of waste elements to a glass frit increases the percentage of BO$$_{3}$$ and decreases that of BO$$_{4}$$. By decreasing the SiO$$_{2}$$/Al$$_{2}$$O$$_{3}$$ ratio or increasing the (SiO$$_{2}$$+B$$_{2}$$O$$_{3}$$)/Al$$_{2}$$O$$_{3}$$ ratio in the glass composition, the BO$$_{3}$$ percentage increases and the BO$$_{4}$$ percentage decreases. Addition of P$$_{2}$$O$$_{5}$$ decreases the BO$$_{3}$$ percentage and increases the BO$$_{4}$$ percentage. Following results were obtained from XAFS measurement of the waste elements. Cerium (Ce) valence is more reduced with the increase of the B$$_{2}$$O$$_{3}$$ content. Addition of P$$_{2}$$O$$_{5}$$ has a tendency to reduce the Ce valence and to enhance deposition of Zr oxide. Deposition of ruthenium compounds separated from glass phase can not be improved by changing the B$$_{2}$$O$$_{3}$$ content. This study was performed as a part of the project, "Improvement of vitrification process of high-level radioactive liquid wastes" on the foundation business of the Agency for Natural Resources and Energy.

Journal Articles

Defect structure analysis of heterointerface between Pt and CeO$$_{rm x}$$ promoter on Pt electro-catalyst

Fugane, Keisuke*; Mori, Toshiyuki*; Yan, P.*; Masuda, Takuya*; Yamamoto, Shunya; Ye, F.*; Yoshikawa, Hideki*; Auchterlonie, G.*; Drennan, J.*

ACS Applied Materials & Interfaces, 7(4), p.2698 - 2707, 2015/02

 Times Cited Count:22 Percentile:30.8(Nanoscience & Nanotechnology)

no abstracts in English

Journal Articles

Oxygen thermochemistry of urania-rare earth system; UO$$_2$$-CeO$$_2$$

Hirooka, Shun; Murakami, Tatsutoshi; Nelson, A. T.*; McClellan, K. J.*

INL/EXT-14-33515, p.34 - 36, 2014/10

Collaborative study has been done on the properties of nuclear materials between the DOE and Japan and the oxygen potential of (U,Ce)O$$_2$$ was measured in this year. Experimental measurements of the oxygen potential were conducted on Ce=20% and 30% composition rates simulating Pu content in advanced MOX fuel in JAEA by gas equilibrium method where oxygen partial pressure in the atmosphere was controlled with mixing dry/wet Ar/H$$_2$$ gas. More than 100 data points were obtained in the O/M range of 1.945 $$sim$$ 2.000 at 1200$$^{circ}$$C, 1400$$^{circ}$$C and 1600$$^{circ}$$C. The experimental results were analyzed by the defect analysis and analytical equations were obtained to calculate O/M as functions of temperature and oxygen potential. From the comparison with that of (U,Pu)O$$_2$$, applicability of the same defect chemistry and S-style curve are common. Also, it is revealed that (U,Ce)O$$_2$$ requires evidently higher oxygen potential for the O/M.

JAEA Reports

Re-evaluation of neutron nuclear data for $$^{242m}$$Am, $$^{243}$$Am, $$^{99}$$Tc and $$^{140}$$Ce

Nakagawa, Tsuneo; Iwamoto, Osamu; Hasegawa, Akira

JAERI-Research 2002-035, 94 Pages, 2002/12

JAERI-Research-2002-035.pdf:2.73MB

no abstracts in English

Journal Articles

Complex magnetic phase diagram of CeRh$$_{2}$$Ge$$_{2}$$

Abe, Hideki*; Yoshii, Kenji; Kitazawa, Hideaki*

Physica B; Condensed Matter, 312-313, p.253 - 255, 2002/03

 Times Cited Count:2 Percentile:84.64(Physics, Condensed Matter)

no abstracts in English

JAEA Reports

Development of analytical method for plutonium in high active liquid waste solution by high performance spectrophotometry

Jitsukata, Shu*; *; ; ; Kurosawa, A.

JNC-TN8410 2001-002, 66 Pages, 2000/12

JNC-TN8410-2001-002.pdf:2.03MB

It was required from IAEA to determine a small amount of plutonium in the high active liquid waste solutions (HALW) in the tokai reprocessing plant. High performance spectrophotometer (HPSP), which could be obtained lower detection limit than conventional spectrophotometer, is studied to be applied to the inspection and verification analysis by the IAEA. [Cold Test] Neodymium, showing an absorption peak near the absorption wavelength of plutonium (VI), was used as an alternative element to plutonium, in order to review the calculation method of the peak intensity. As a result, the three-point correction method was found to be simple and effective. [Hot Test] Plutonium nitrate solution was used the fundamental test of this method. Since the method is known to be influenced by acidity, suspended sludge and coexistent elements in a sample, each dependency was examined. It was found that measurement results varied about 14% at a nitric acid concentration of 2-4 mol/L. Sludge should be removed by filtration before the measurement. The effect of coexisting elements could be eliminated adjusting the optical balance between reference and sample beam intensity. In the case of measuring a low concentration plutonium solution sample, a ratio of the peak intensity to the background intensity (S/B ratio) is relatively small. Therefore a method should be improved the S/B ratio by analyzing the obtained spectra. Accumulated average method, moving average method and Fourier transform method was tested. The results showed that a combination of the accumulated average method and the moving average method was the optimum method for the purpose. Linearity of the calibration curve was found between 0-11 mgPu/L. Synthetic sample solution, which simulated the actual constituents of the HALW with plutonium showed a good linear relation at 0-11 mgPu/L. The detection limit for plutonium concentration was 0.07 mgPu/L. When the synthetic HALW solution containing plutonium was measured, the de

JAEA Reports

Decontamination factor of the commerciaI detergents for the skin (Part 3)

Miyabe, Kenjiro; Takasaki, Koji; *; *

JNC-TN8420 2000-007, 100 Pages, 2000/08

JNC-TN8420-2000-007.pdf:7.66MB

The commercial detergents, which are cleansing cream, shampoo, neutral detergent, etc., were examined in order to select the body cleaners that are substitutes for the titanium dioxide paste. JNC entrusted Japan Environment Research Corporation Limited with these examinations since 1997. In 1997 and 1998, the commercial detergents were examined for Ce-144, Cs-137 and Ru-106. In 1999, 22 detergents were examined for Co-60 from the result of the past examinations. In this examination, the radioactive solution of Co-60 was dropped on the pig-skin samples. These samples were washed with each detergent after 5 minutes and 40 minutes. The decontamination factors of detergents were estimated by the radioactive ratio of the samples before and after washing. As a result of this examination, the decontamination factors for Co-60 was the same as the decontamination factors for Ce-144 and Cs-137, and 11 detergents were nominated as the cleaner that have the decontamination factor more than that of titanium dioxide paste.

JAEA Reports

Observation of melt surface depressions during electron beam evaporation

Oba, Hironori; Shibata, Takemasa

JAERI-Research 2000-032, 17 Pages, 2000/08

JAERI-Research-2000-032.pdf:2.65MB

no abstracts in English

JAEA Reports

None

Yamanaka, Shinsuke*; Abe, Kazuyuki

JNC-TY9400 2000-004, 78 Pages, 2000/03

JNC-TY9400-2000-004.pdf:2.39MB

no abstracts in English

Journal Articles

Production of Ce negative ions by Cs sputter ion source

Saito, Yuichi; Yotsombat, B.*; Mizuhashi, Kiyoshi; Tajima, Satoshi

Review of Scientific Instruments, 71(2), p.955 - 957, 2000/02

 Times Cited Count:9 Percentile:45.6(Instruments & Instrumentation)

no abstracts in English

Journal Articles

Charge transfer cross sections for dysprosium and cerium

Tamura, Koji; Adachi, Hajime; Shibata, Takemasa

Japanese Journal of Applied Physics, Part 1, 38(5A), p.2973 - 2977, 1999/05

 Times Cited Count:6 Percentile:66.34(Physics, Applied)

no abstracts in English

Journal Articles

Production of stable atomic beam in electron beam evaporation process

Oba, Hironori; Shibata, Takemasa

Japanese Journal of Applied Physics, Part 1, 38(7A), p.4258 - 4259, 1999/00

 Times Cited Count:0 Percentile:100(Physics, Applied)

no abstracts in English

JAEA Reports

None

; ; ; ; Takeda, Seiichiro

PNC-TN8410 98-078, 36 Pages, 1998/07

PNC-TN8410-98-078.pdf:1.11MB

None

JAEA Reports

Charge transfer cross sections for dysprosium and cerium

Adachi, Hajime; Tamura, Koji; ; Shibata, Takemasa

JAERI-Research 98-030, 29 Pages, 1998/06

JAERI-Research-98-030.pdf:1.22MB

no abstracts in English

JAEA Reports

A Study on nuclide migration in buffer materials and rocks for geological disposal of radioactive waste

Sato, Haruo

PNC-TN8410 97-202, 205 Pages, 1998/01

PNC-TN8410-97-202.pdf:14.14MB

This thesis summarizes the results investigated in order to establish a basic theory on the predictive method of diffusion coefficients of nuclides in compacted sodium bentonite which is a candidate buffer material and in representative rocks for the geological disposal of radioactive waste by measuring the pore structural factors of the compacted bentonite and rocks such as porosity and tortuosity, measuring diffusion coefficients of nuclides in the bentonite and rocks, acquiring basic data on diffusion and developing diffusion models which can quantitatively predict nuclide migration in long-term. This consists of 7 chapters. Chapter 1 is the introduction, in which conventional studies on nuclide migration in buffer materials and rocks for the geological disposal of radioactive waste carried out to date are reviewed, and those problems are summarized as well as the objectives of this study are described. Besides, the difinition of geological disposal is explained. In Chapter 2, it is described on non-steady state diffusion of HTO, Sr-90, Tc-99, I-129, Cs-137, Np-237, Am-241 and Pu in purified sodium bentonite, Kunipia-F, in which the rate of constituent Na-smectite was raised approximately 100wt%. In-diffusion experiments were carried out in a range of bentonite densities of 200 $$sim$$ 2000 kg$$cdot$$m$$^{-3}$$ under ambient aerobic conditions at room temperature (20 $$sim$$ 23$$^{circ}$$C), and apparent diffusion coefficients (Da) were obtained. The apparent diffusion coefficients decreased with increasing dry density of bentonite. It was quantitatively indicated from diffusion experiments using HTO that these Da values include the effect of geometric retardation such as the tortuosity factor of compacted bentonite. It was experimentally clarified that Da is not affected by diffusion time based on diffusion experiments for different experimental periods using Sr and Cs. Moreover, it was also experimentally clarified that Da is not affected by tracer ...

Journal Articles

Production of stable atomic beam in an electron beam evaporation process

Oba, Hironori; Shibata, Takemasa

Proc. of 6th Workshop on Separation Phenomena in Liquids and Gases (SPG'98), p.241 - 245, 1998/00

no abstracts in English

66 (Records 1-20 displayed on this page)