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Journal Articles

Stroboscopic time-of-flight neutron diffraction during cyclic testing using the event data recording system at J-PARC

Kawasaki, Takuro; Inamura, Yasuhiro; Ito, Takayoshi*; Nakatani, Takeshi; Harjo, S.; Gong, W.*; Aizawa, Kazuya

Journal of Applied Crystallography, 51(3), p.630 - 634, 2018/06

 Times Cited Count:2 Percentile:29.6(Chemistry, Multidisciplinary)

Journal Articles

Correlation between intermolecular hydrogen bonds and melting points of uranyl nitrate complexes with cyclic urea derivatives

Suzuki, Tomoya; Takao, Koichiro*; Kawasaki, Takeshi*; Harada, Masayuki*; Nogami, Masanobu*; Ikeda, Yasuhisa*

Polyhedron, 96, p.102 - 106, 2015/08

 Times Cited Count:5 Percentile:47(Chemistry, Inorganic & Nuclear)

We have determined crystal structures of UO$$_{2}$$(NO$$_{3}$$)$$_{2}$$(${bf 0a}$)$$_{2}$$ (${bf 0a}$: 2-imidazolidone), UO$$_{2}$$(NO$$_{3}$$)$$_{2}$$(${bf 0b}$)$$_{2}$$ (${bf 0b}$: tetrahydro-2-pyrimidone) and UO$$_{2}$$(NO$$_{3}$$)$$_{2}$$(${bf 1a}$)$$_{2}$$ (${bf 1a}$: 1-methyl-2-imidazolidone) by using single crystal X-ray analysis, and examined correlations between melting points (mps) and intermolecular hydrogen bonds (HBs) of UO$$_{2}$$(NO$$_{3}$$)$$_{2}$$(CU)$$_{2}$$ (CU: cyclic urea derivatives) and UO$$_{2}$$(NO$$_{3}$$)$$_{2}$$(NRP)$$_{2}$$ (NRP: pyrrolidone derivative).

Journal Articles

Studies on the extraction of soft acid metal species using MIDOA and analogous compounds

Sasaki, Yuji; Saeki, Morihisa; Sugo, Yumi; Ikeda, Yasuhisa*; Kawasaki, Takeshi*; Suzuki, Tomoya*; Ohashi, Akira*

Solvent Extraction Research and Development, Japan, 22(1), p.37 - 45, 2015/05

 Times Cited Count:9 Percentile:37.92(Chemistry, Multidisciplinary)

An extractant, methylimino-bis-${it N,N'}$-dioctylacetamide (MIDOA), was used for the extraction of soft acid metals. It was found that MIDOA can extract not only Cr(VI), Mo(VI), W(VI), Tc(VII) and Re(VII), whose metals can form the oxonium anions due to their high oxidation states, but also other metal cations, like Nb(V), Ta(V) and Pd(II). Analogous compounds, imino-bis-${it N,N'}$-dioctylacetamide (IDOA) and methylimino-bis-${it N,N'}$-di-2-ethylhexylacetamide (MIDEHA), are synthesized and compared for their extractability. It is clear that these extractants have almost same or lower $$D$$ values than those for MIDOA. In order to examine the effect on extractability with different donor atoms, TODGA (${it N,N,N',N'}$-tetraoctyl-diglycolamide) and TDGA (${it N,N,N',N'}$-tetraoctyl-tyiodiglycolamide) having oxygen and sulfur donor are employed. The comparison of their extractabilities suggests that the trend of Pd and Re extraction is N $$>$$ S $$>$$ O and N $$>$$ O $$>$$ S, respectively.

Journal Articles

Density and X-ray emission profile relationships in highly ionized high-Z laser-produced plasmas

Yoshida, Kensuke*; Fujioka, Shinsuke*; Higashiguchi, Takeshi*; Ugomori, Teruyuki*; Tanaka, Nozomi*; Kawasaki, Masato*; Suzuki, Yuhei*; Suzuki, Chihiro*; Tomita, Kentaro*; Hirose, Ryoichi*; et al.

Applied Physics Letters, 106(12), p.121109_1 - 121109_5, 2015/03

 Times Cited Count:6 Percentile:32.7(Physics, Applied)

Journal Articles

Efficient extreme ultraviolet emission from one-dimensional spherical plasmas produced by multiple lasers

Yoshida, Kensuke*; Fujioka, Shinsuke*; Higashiguchi, Takeshi*; Ugomori, Teruyuki*; Tanaka, Nozomi*; Ohashi, Hayato*; Kawasaki, Masato*; Suzuki, Yuhei*; Suzuki, Chihiro*; Tomita, Kentaro*; et al.

Applied Physics Express, 7(8), p.086202_1 - 086202_4, 2014/08

 Times Cited Count:24 Percentile:75.15(Physics, Applied)

We demonstrate high conversion efficiency for extreme ultraviolet (EUV) emission at 6.5-6.7 nm from multiple laser beam-produced one-dimensional spherical plasmas. Multiply charged-state ions produce strong resonance emission lines, which combine to yield intense unresolved transition arrays in Gd, Tb, and Mo. The maximum in-band EUV conversion efficiency was observed to be 0.8%, which is one of the highest values ever reported due to the reduction of plasma expansion loss.

JAEA Reports

"Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds" summary of the researches for three years (Contract research)

Sasaki, Yuji; Tsubata, Yasuhiro; Kitatsuji, Yoshihiro; Sugo, Yumi; Shirasu, Noriko; Ikeda, Yasuhisa*; Kawasaki, Takeshi*; Suzuki, Tomoya*; Mimura, Hitoshi*; Usuda, Shigekazu*; et al.

JAEA-Research 2014-008, 220 Pages, 2014/06

JAEA-Research-2014-008.pdf:41.81MB

The researches on Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds, entrusted to Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan, from 2010 to 2012 are summarized. This project was composed of three themes, those are (1) Development of total recovery of MA+Ln: basic researches for new extractant, DOODA, (2) Development of mutual separation of Am/Cm/Ln: basic researches of Ln-complex, solvent extraction, and extraction chromatography, and (3) Evaluation of separation technique: process simulation. For topic (1), we summarized the information on characteristic of DOODA extractant. For topic (2), we summarized the information on structures of Ln-complexes, solvent extraction and chromatography. For topic (3), we summarized the information on conditions of mixer-settler and evaluation of each fraction separated.

JAEA Reports

Development of the conductive glove for glove box operation; Production of prototypes and their experimental results

Kodato, Kazuo; Enuma, Masahito; Kawasaki, Takeshi; Nogami, Yoshitaka; Kaneko, Kazunori; Kimura, Masanori*; Yasumori, Tomokazu*

JAEA-Research 2013-017, 45 Pages, 2014/02

JAEA-Research-2013-017.pdf:3.98MB

The glove used at glove boxes in the nuclear fuel plants is usually made with Chlorosulfonated polyethylene rubber. The rubber is excellent in terms of resistance to radiation because it has no double bond in its main chain of the component, however, it deteriorates rapidly in high dose environment such as direct contact of alpha ray1). Plutonium oxide powder is treated in glove boxes at plutonium fuel facilities where the alpha ray from plutonium oxide power attached on surface of a glove causes the deterioration of the rubber. Therefore the effective method for prevent of the rapid deterioration is to decrease the amount of attached powder, and the glove with conductive property which can prevent static generation on its surface has been developed and tested. The results showed that the rubber has less adherent property to powder compared with conventional one.

Journal Articles

Stability of polyvinylpolypyrrolidone against $$gamma$$-ray irradiation in HNO$$_{3}$$ media

Nogami, Masanobu*; Sugiyama, Yuichi*; Kawasaki, Takeshi*; Harada, Masayuki*; Kawata, Yoshihisa*; Morita, Yasuji; Kikuchi, Toshiaki*; Ikeda, Yasuhisa*

Journal of Radioanalytical and Nuclear Chemistry, 296(1), p.423 - 427, 2013/04

 Times Cited Count:5 Percentile:43.78(Chemistry, Analytical)

Stability of polyvinylpolypyrrolidone (PVPP), a resin with adsorption selectivity to U(VI) in nitric acid media, against $$gamma$$-ray irradiation has been examined using HNO$$_{3}$$ solutions of various concentrations. As the result, no clear decrease in the capacity was observed for any samples. Or rather, it was found that the capacity increased by approximately 50% for the PVPP slurry irradiated in 6 M HNO$$_{3}$$. The infrared spectroscopic study indicates that PVPP degrades by $$gamma$$-ray irradiation in HNO$$_{3}$$ from the cleavage of the pyrrolidone ring by the addition of oxygen atom originating from HNO$$_{3}$$, followed by the formation of chain monoamides with multiple coordinative atoms by the continuous addition of oxygen, finally leading to the generation of primary-amine type anion exchange resin. It is also indicated that all generated functional groups possess adsorptivity to U(VI) in 3 M HNO$$_{3}$$.

Journal Articles

Stability of pyrrolidone derivatives against $$gamma$$-ray irradiation

Nogami, Masanobu*; Sugiyama, Yuichi*; Kawasaki, Takeshi*; Harada, Masayuki*; Kawata, Yoshihisa*; Morita, Yasuji; Kikuchi, Toshiaki*; Ikeda, Yasuhisa*

Science China; Chemistry, 55(9), p.1739 - 1745, 2012/09

 Times Cited Count:4 Percentile:21.58(Chemistry, Multidisciplinary)

Stability of N-alkylated pyrrolidone derivatives (NRPs) against radiation was examined by irradiation tests with $$^{60}$$Co $$gamma$$-ray. We have been developed a novel reprocessing system using NRPs which have precipitation ability to haxa- and tetravalent actinides in nitric acid media. Degradation rates of NRPs are evaluated by irradiation in 3M nitric acid solutions and mechanism of degradation are discussed in the present paper.

Journal Articles

Development of advanced reprocessing system based on precipitation method using pyrrolidone derivatives as precipitants; Overall evaluation of system

Ikeda, Yasuhisa*; Kawasaki, Takeshi*; Harada, Masayuki*; Nogami, Masanobu*; Kawata, Yoshihisa*; Kim, S.-Y.*; Morita, Yasuji; Chikazawa, Takahiro*; Someya, Hiroshi*; Kikuchi, Toshiaki*

Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 5 Pages, 2011/12

An advanced reprocessing system for spent FBR fuels based on two precipitation processes using pyrrolidone derivatives as precipitants has been developed. Experimental results of precipitation behavior of U, Pu and other elements, the heat- and radiation-resistance of precipitants, the thermal decomposition properties of precipitates showed that N-n-butyl-2-pyrrolidone and N-neopentyl-2-pyrrolidone are the appropriate precipitants for the first and second precipitation steps, respectively. From the engineering investigation, We confirmed that the precipitation and the filtration can be done efficiently using the engineering scale equipment and that the fuel pellets are directly prepared by the calcination of the precipitates. On the basis of these results, we evaluated that the proposed system is expected to be one of candidates of the future reprocessing systems for spent FBR fuels.

Journal Articles

Precipitation ability to U(IV) and stability of 1,3-dimethyl-2-imidazolidone for selective precipitation of U(VI) in nitric acid media

Nogami, Masanobu*; Harada, Masayuki*; Sugiyama, Yuichi*; Kawasaki, Takeshi*; Kawata, Yoshihisa*; Morita, Yasuji; Kikuchi, Toshiaki*; Ikeda, Yasuhisa*

Progress in Nuclear Energy, 53(7), p.948 - 951, 2011/09

 Times Cited Count:3 Percentile:28.8(Nuclear Science & Technology)

The precipitation ability of 1,3-dimethyl-2-imidazolidone (DMI) to U(VI) and U(IV) was examined using nitric acid solutions. While DMI precipitated U(VI) from 3 M nitric acid, no precipitate was observed in the solution containing 0.15 M U(IV) and 3 M nitric acid by adding DMI at the ratio of [DMI]/[U(IV)]=5. This indicates that the selectivity of DMI to U(VI) than U(IV). In spite of the excellent selectivity to U(VI), DMI has a disadvantage on the stability in nitric acid, because gradual acid hydrolysis of DMI is inevitable due to the nature of the chemical structure. Experiments on the stability of DMI in $$gamma$$-ray irradiation and heating in nitric acid solutions showed that the stability is strongly affected by the concentration of nitric acid and that DMI may be applicable in nitric acid solutions up to ca. 2 M.

JAEA Reports

Replacement technology for front acrylic panels of a large-sized glove box using bag-in / bag-out method

Sakuraba, Naotoshi; Numata, Masami; Komiya, Tomokazu; Ichise, Kenichi; Nishi, Masahiro; Tomita, Takeshi; Usami, Koji; Endo, Shinya; Miyata, Seiichi; Kurosawa, Tatsuya; et al.

JAEA-Technology 2009-071, 34 Pages, 2010/03

JAEA-Technology-2009-071.pdf:21.07MB

As a part of maintenance technology of a large-sized glove box for handling of TRU nuclides, we developed replacement technology for front acrylic panels using the bag-in/bag-out method and applied this technology to replace the deteriorated front acrylic panels at Waste Safety Testing Facility (WASTEF) in Nuclear Science Research Institute of Japan Atomic Energy Agency (JAEA). As a consequence, we could safely replace the front acrylic panels under the condition of continuous negative pressure only with partial decontamination of the glove box. We also demonstrated that the present technology is highly effective in points of safety, workability and cost as compared to the usual replacement technology for front acrylic panels of a glove box, where workers in an air-line suit replace directly the front acrylic panels in a green house.

Journal Articles

Adsorptivity of polyvinylpolypyrrolidone for selective separation of U(VI) from nitric acid media

Nogami, Masanobu*; Sugiyama, Yuichi*; Kawasaki, Takeshi*; Harada, Masayuki*; Morita, Yasuji; Kikuchi, Toshiaki*; Ikeda, Yasuhisa*

Journal of Radioanalytical and Nuclear Chemistry, 283(2), p.541 - 546, 2010/02

 Times Cited Count:18 Percentile:79.59(Chemistry, Analytical)

Adsorptivity of polyvinylpolypyrrolidone (PVPP) to various metal ions was examined as a part of the development of resins with selectivity to U(VI) in nitric acid media. It was found that PVPP has a strong adsorptivity to U(VI) in wide concentration range of nitric acid. The mechanism of U(VI) adsorption by PVPP was discussed by results of Scatchard plot analysis and infrared spectroscopic analysis. Furthermore, it was found that fission productions except for Re(VII) as the simulant of Tc(VII) and Pd(II) are not adsorbed on to PVPP and that Pd(II) and Re(VII) species are weakly adsorbed in the lower concentration ranges of nitric acid, where the adsorption rates of Pd(II) are extremely slower than those of U(VI). These results indicate that U(VI) can be separated from other metal ions by PVPP.

Journal Articles

Study on degradation properties of NBP precipitant by $$gamma$$-ray irradiation

Nogami, Masanobu*; Sugiyama, Yuichi*; Kawasaki, Takeshi*; Harada, Masayuki*; Kawata, Yoshihisa; Morita, Yasuji; Kikuchi, Toshiaki*; Ikeda, Yasuhisa*

JAEA-Review 2009-041, JAEA Takasaki Annual Report 2008, P. 25, 2009/12

As a part of the development of a novel reprocessing system for spent FBR fuels based on the precipitation method, influence of concentrations of HNO$$_{3}$$ on the stability by $$gamma$$-ray irradiation was examined for $$N$$-$$n$$-butyl-2-pyrrolidone (NBP), a candidate precipitant for the first precipitation step for selectively precipitating U(VI). The residual ratios of the samples for HNO$$_{3}$$ solutions up to 3 M were found to be decreased identically, where ca. 20% of NBP was degraded after the irradiation of 1 MGy. It was found that the degradation of the samples of 6 M HNO$$_{3}$$ is more distinguished, where ca. 30% was degraded after the irradiation of 0.1 MGy. As the result of the investigation of the degradation mechanism of NBP, it was revealed that the degradation started from the cleavage of the pyrrolidone ring of NBP by the addition of oxygen atom, followed by the formation of chain monoamides and C4 compounds by the continuous addition of oxygen, leading to the generation of oxalic acid.

Journal Articles

Progress in R&D efforts on the energy recovery linac in Japan

Sakanaka, Shogo*; Ago, Tomonori*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; Harada, Kentaro*; Hiramatsu, Shigenori*; Honda, Toru*; et al.

Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM), p.205 - 207, 2008/06

Future synchrotron light sources based on the energy-recovery linacs (ERLs) are expected to be capable of producing super-brilliant and/or ultra-short pulses of synchrotron radiation. Our Japanese collaboration team is making efforts for realizing an ERL-based hard X-ray source. We report recent progress in our R&D efforts.

JAEA Reports

Confirmation tests for fabrication of low density MOX pellet for FBR

Murakami, Tatsutoshi; Suzuki, Kiichi; Hatanaka, Nobuhiro; Hanawa, Yukio; Shinozaki, Masaru; Murakami, Shinichi; Tobita, Yoshimasa; Kawasaki, Takeshi; Kobayashi, Yoshihito; Iimura, Naoto; et al.

JAEA-Technology 2008-017, 97 Pages, 2008/03

JAEA-Technology-2008-017.pdf:2.76MB

Low density MOX pellets for FBR "MONJU" have not been fabricated in Plutonium Fuel Fabricating Facility (PFPF) for these 9 years since completion of the first reload fuel for "MONJU" in 1995. In this period, about 60 % of machines in the pellet fabrication process of PFPF have been replaced with new ones, and fabrication of MOX pellets for "JOYO" has been continued using these machines. Concerning the feed MOX powders for "MONJU", the amount of decay heat has been increased with increase of accumulated Am-241 in this period. In addition, powder characteristic of recycled MOX powder which is one of feed powders, MH-MOX powder, UO$$_{2}$$ powder and recycled MOX powder, was significantly changed by replacing former processing machine used for scrap recycling with improved one. Using MOX powder with increased decay heat and recycled MOX powder processed by new machine, a series of low density MOX pellet fabrication tests were conducted to confirm pellet fabrication conditions for current pellet fabrication machines from October in 2004 to August in 2006. As a conclusion, it was confirmed that low density MOX pellets could be fabricated using these feed powders and replaced machines by adjusting pellet fabrication conditions adequately. This report summarizes the results of a series of low density MOX pellet fabrication tests.

Journal Articles

Revaluation of the correlation of isomer shift with Np-O bond length in various neptunyl(V and VI) compounds

Saeki, Masakatsu; Nakada, Masami; Kawasaki, Takeshi*; Nishimura, Tatsuru*; Kitazawa, Takafumi*; Takeda, Masuo*

Journal of Radioanalytical and Nuclear Chemistry, 270(2), p.379 - 384, 2006/11

 Times Cited Count:1 Percentile:10.64(Chemistry, Analytical)

no abstracts in English

Journal Articles

$$^{115}$$In-NQR study of antiferromagnetism and superconductivity in CeRhIn$$_5$$ and CeIn$$_3$$ under pressure

kawasaki, Shinji*; Yashima, Mitsuharu*; kotegawa, Yu*; Mito, Takeshi*; Kawasaki, Yu*; Zheng, G.-Q.*; Kitaoka, Yoshio*; Shishido, Hiroaki*; Araki, Shingo*; Aoki, Dai*; et al.

Journal of Physics and Chemistry of Solids, 67(1-3), p.497 - 499, 2006/01

 Times Cited Count:2 Percentile:14.21(Chemistry, Multidisciplinary)

We report the novel phase diagram of superconductivity (SC) and antiferromagnetism (AFM) in heavy-fermion (HF) pressure ($$P$$)-induced superconductors CeRhIn$$_5$$ and CeIn$$_3$$ through nuclear-quadrupole-resonance (NQR) measurements under $$P$$. The $$P$$-induced superconductivity in CeRhIn$$_5$$ coexists with AFM on a microscopic level in 1.5-1.9 GPa. By contrast, in CeIn$$_3$$, the $$P$$-induced phase separation of AFM and paramagnetism (PM) takes place without any trace of a quantum phase transition. The outstanding finding is that SC sets in at both the phasesmagnetically separated into AFM and PM in 2.28-2.5 GPa.

JAEA Reports

Rise-to-power test in High Temperature Engineering Test Reactor; Test progress and summary of test results up to 30MW of reactor thermal power

Nakagawa, Shigeaki; Fujimoto, Nozomu; Shimakawa, Satoshi; Nojiri, Naoki; Takeda, Takeshi; Saikusa, Akio; Ueta, Shohei; Kojima, Takao; Takada, Eiji*; Saito, Kenji; et al.

JAERI-Tech 2002-069, 87 Pages, 2002/08

JAERI-Tech-2002-069.pdf:10.12MB

Rise-to-power test in the HTTR has been performed from April 23rd to June 6th in 2000 as phase 1 test up to 10MW, from January 29th to March 1st in 2001 as phase 2 test up to 20MW in the rated operation mode and from April 14th to June 8th in 2001 as phase 3 test up to 20MW in the high temperature test operation mode. Phase 4 test to achieve the thermal reactor power of 30MW started from October 23rd in 2001. On December 7th it was confirmed that the thermal reactor power reached to 30MW and the reactor outlet coolant temperature reached to 850$$^{circ}$$C. JAERI obtained the certificate of pre-operation test from MEXT because all the pre-operation tests by MEXT were passed successfully. From the test results of rise-up-power test up to 30MW, the performance of reactor and cooling system were confirmed, and it was confirmed that an operation of reactor facility could be performed safely. Some problems to be solved were found through tests. By means of solving them, the reactor operation with the reactor outlet coolant temperature of 950$$^{circ}$$C will be achievable.

Journal Articles

First test results for the ITER central solenoid model coil

Kato, Takashi; Tsuji, Hiroshi; Ando, Toshinari; Takahashi, Yoshikazu; Nakajima, Hideo; Sugimoto, Makoto; Isono, Takaaki; Koizumi, Norikiyo; Kawano, Katsumi; Oshikiri, Masayuki*; et al.

Fusion Engineering and Design, 56-57, p.59 - 70, 2001/10

 Times Cited Count:17 Percentile:76.5(Nuclear Science & Technology)

no abstracts in English

48 (Records 1-20 displayed on this page)