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Sakamoto, Fuminori; Nankawa, Takuya; Onuki, Toshihiko; Fujii, Tsutomu*; Iefuji, Haruyuki*
Geomicrobiology Journal, 29(5), p.470 - 476, 2012/05
Times Cited Count：6 Percentile：17.37(Environmental Sciences)We screened 4908 non-essential gene deletion mutant yeast strains for uranium sensitivity and low accumulation by growth in agar medium containing uranium. All mutant strains grew successfully on agar media containing 0 or 0.5 mM uranium for one week at 30 centigrade. Thirteen strains with single gene deletions showed reduced growth in the agar medium containing 0.5 mM uranium and were identified as uranium-sensitive mutant strains. The phosphate transporter genes of PHO86, PHO84, PHO2, and PHO87 were among the deleted genes in the uranium-sensitive mutant strains, suggesting that genes concerned with phosphate transport contribute to uranium tolerance. Seventeen single-deletion strains showed lower uranium accumulation than the wild-type after exposure to agar medium containing 0.5 mM uranium, and were identified as mutant strains with low uranium accumulation.
Kiyanagi, Yoshiaki*; Kino, Koichi*; Furusaka, Michihiro*; Hiraga, Fujio*; Kamiyama, Takashi*; Kato, Kiyoshi*; Igashira, Masayuki*; Katabuchi, Tatsuya*; Mizumoto, Motoharu*; Oshima, Masumi; et al.
Journal of the Korean Physical Society, 59(2), p.1781 - 1784, 2011/08
Times Cited Count：13 Percentile：62.2(Physics, Multidisciplinary)The project of the comprehensive nuclear data research for the development of the advanced reactor systems had been executed successfully by eight organizations from 2005 to 2009. In this project, we constructed the pulsed neutron beamline that was aimed to obtain neutron capture cross-sections of long-lived fission products and minor actinides accurately. The energy spectra, spatial distributions, and pulses of the beam were studied by measurements and simulation calculations, and they were found to be consistent with those of the beamline design. In this paper, we present the overview of the project and the properties of the neutron beam provided by this beam line.
to heavy element stress; Lead vs. uraniumSakamoto, Fuminori; Onuki, Toshihiko; Fujii, Tsutomu*; Iefuji, Haruyuki*
Geomicrobiology Journal, 27(3), p.240 - 244, 2010/05
Times Cited Count：8 Percentile：24.12(Environmental Sciences)We have examined the responses of in media containing Pb
ions and compared it to those in media containing UO
ions to elucidate the stress effects of heavy elements. Cultivation of 
in a medium containing 1.0
10
M Pb showed nearly the same growth as that in the control medium while growth was inhibited in the medium containing 1.010
M Pb. Backscattering electron image analyses of thin sections of cells showed that Pb had accumulated inside the cells. Two-dimensional (2D) gel electrophoresis analysis of the proteins extracted from the exposed to Pb ions showed that several specific protein spots were expressed after cultivation with Pb, that did not appear in the control medium. Our results suggest that Pb more weakly inhibits the growth of than UO, and produces different stresses in than UO.
Kurita, Tsutomu; Kato, Yoshiyuki; Yoshimoto, Katsunobu; Suzuki, Masahiro; Kihara, Yoshiyuki; Fujii, Kanichi
Proceedings of International Conference on Advanced Nuclear Fuel Cycle; Sustainable Options & Industrial Perspectives (Global 2009) (CD-ROM), p.94 - 102, 2009/09
With regard to advanced MOX fuel fabrication, a new concept in which one vessel especially designed to meet microwave de-nitration is utilized also for crushing and for granulation, without organic lubricant nor powder transfer across the processes, was introduced for innovative MOX powder production. In order to realize this concept, two attempts were made: A specially designed three blade impeller coupled with auxiliary blade. A uniquely shaped mixing blade coupled with an auxiliary blade having auto-orbital hybrid rotation. The mixing blade promotes the growth of particles, whereas the auxiliary blade suppresses the overgrowth by chopping larger particles. These granulators use a little water as binder. As a result, major diameter of granule 400-1000 micron and flow-ability 82-85 was obtained with fine WO
model powder. Therefore, a prospect to satisfy both desirable powder properties and simplified nuclear material production was opened, as well as improvement of working efficiency and cut down on costs.
Ono, Masao; Iguchi, Yusuke*; Okayasu, Satoru; Esaka, Fumitaka; Kobayashi, Katsura*; Hao, T.; Bagum, R.*; Osawa, Takahito; Fujii, Kimio; Nakamura, Eizo*; et al.
Defect and Diffusion Forum, 289-292, p.63 - 68, 2009/04
The atomic-scale graded structure of In-Pb alloy was formed by an ultracentrifuge experiment under conditions that a gravitational field of 0.8110
G for 100 hours at 150 
C in solid state in our previous study. The isotope ratio measurements were performed on the centrifuged sample with secondary ion mass spectrometer (SIMS). 
Pb/
Pb and 
Pb/Pb isotope ratio changed with negative gradient in the direction of centrifugal force approximately 1.5% and 0.8%, respectively. And three-isotope diagram of Pb/Pb versus Pb/Pb proved that the isotope fluctuation depends on isotopic mass difference. These results showed that the strong gravitational field not only affected on the inter-diffusion but also on self-diffusion in this alloy as causing isotope fractionation effect, and the isotope fractionation was dependent on mass-difference.
Ono, Masao; Iguchi, Yusuke*; Okayasu, Satoru; Esaka, Fumitaka; Kobayashi, Katsura*; Hao, T.; Bagum, R.*; Osawa, Takahito; Fujii, Kimio; Nakamura, Eizo*; et al.
Journal of Nuclear Science and Technology, 45(Suppl.6), p.108 - 110, 2008/09
Times Cited Count：1 Percentile：10.05(Nuclear Science & Technology)The atomic-scale graded structure of In-Pb alloy was formed by an ultracentrifuge experiment under conditions that a gravitational field of 810,000 G for 100 hours at 150C (solid state) in our previous study. The isotope fluctuation on this sample was measured using secondary ion mass spectrometer (SIMS). The ratio both Pb/Pb and 
In/
In changed with positive gradient in the direction of centrifugal force approximately 1.2%. These isotope fluctuations were larger than that of starting state of natural state (In
0.2%, Pb0.1%). These show that the sedimentation of isotopes occurred by solid centrifugation in this alloy, although achieved concentration gradients were small.
Suzuki, Masahiro; Ishii, Katsunori; Yamamoto, Takuma; Kihara, Yoshiyuki; Kato, Yoshiyuki; Kurita, Tsutomu; Yoshimoto, Katsunobu; Fujii, Kanichi
Proceedings of Global Congress on Microwave Energy Applications (GCMEA 2008/MAJIC 1st), p.501 - 504, 2008/08
The natural resources, oil and uranium, would dry up around the midway of this century. FBR cycle most probably rescues this difficult situation. Mass production of MOX fuel for FBR, therefore, is the supreme subject to Japanese energy strategy. For this subject, we are attacking with Microwave heating technology. Up to present, we have succeeded to produce excellent PuO/UO bulk, 2 kgMOX/batch, advancing toward the mass production target, 5 kgU/h for one batch.
Ono, Masao; Iguchi, Yusuke*; Bagum, R.*; Fujii, Kimio; Okayasu, Satoru; Esaka, Fumitaka; Mashimo, Tsutomu*
AIP Conference Proceedings 973, p.476 - 481, 2008/03
We had realized atomic-scale graded structures in several miscible alloys by ultracentrifuge experiment. In this study, we performed an ultracentrifuge experiment on a MgCd order-disorder alloy at disordered state of solid solution. The experimental conditions were as follows: maximum acceleration: 610,000 g, temperature: 400C, composition: Mg:Cd=50:50at%, time duration: 60 h). We investigated the crystal state of the centrifuged sample that had ordered from the disorder state of atomic-scale graded structure. It was found that the graded structure was formed in the centrifuged sample, in which Cd content continuously increased in the direction of gravitational field. It was also found that the different peaks from the starting state appeared in X-ray diffraction patterns of the centrifuged sample. We will present details at the session.
in response to uranium exposureSakamoto, Fuminori; Nankawa, Takuya; Kozai, Naofumi; Fujii, Tsutomu*; Iefuji, Haruyuki*; Francis, A. J.; Onuki, Toshihiko
Journal of Nuclear and Radiochemical Sciences, 8(2), p.133 - 136, 2007/10
Protein expression of grown in the medium containing 
U(VI) and 
U(VI) was examined by two-dimensional gel electrophoresis. of BY4743 was grown in medium containing U of 0, 2.0, and 5.0 10 M or U of 2.5 10
(radioactivity was higher by 350 times than 2.0 10 M U) and 5.0 10 M for 112 h at 30C. The growths of the yeast grown in the above media were in the following order: control 
2.5 10 M U 2.0 10 M U 5.0 10 M U 5.0 10 M U. This result indicated that not only radiological but also chemical effect of U reduced the growth of the yeast. The concentrations of U in the medium containing U or U decreased, suggesting U accumulation by the yeast cells. The 2-D gel electrophoresis analysis showed the appearance of several spots after exposure to U or to U but not in the control containing no uranium. These results show that the yeast cells exposed to U express several specific proteins.
Hishida, Masahiko; Murakami, Tsutomu*; Kisohara, Naoyuki; Fujii, Tadashi; Uchita, Masato*; Hayafune, Hiroki; Chikazawa, Yoshitaka; Usui, Shinichi; Ikeda, Hirotsugu; Uno, Osamu; et al.
JAEA-Research 2006-006, 125 Pages, 2006/03
JAEA-Research-2006-006.pdf:11.55MB
In Phase I of the "Feasibility Studies on Commercialized Fast Reactor Cycle Systems (F/S)", an advanced loop type reactor has been selected as a promising concept of sodium-cooled reactor, which has a possibility to fulfill the design requirements of the F/S. In Phase II, design improvement for further cost reduction and the establishment of the plant concept has been performed. In this study, reactor core design and large-scale plant design have been performed by adopting the modified fuel assembly with inner duct structure and double-wall straight tube steam generator (SG), which concepts were chosen at the interim review of FY 2003. For this SG, safety logics have been studied and the structural concept has been established. And the plant designs improving the in-service inspection (ISI) and repair capability have been performed. Furthermore, elaborate confirmation of the design has been performed reflecting the development of elemental technology, back-up concepts have been proposed. Besides, cost reduction measures have been studied by reducing reactor grade materials, introducing autonomous standardizations, simplifying the design due to deregulation and adopting systemized standards for BOP and NSSS. From now on, reflecting the results of elemental experiments, in-depth design studies and examination of critical issues will be carried out and the plant concept will accomplish in preparation for the final evaluation in Phase II.
Sakamoto, Fuminori; Onuki, Toshihiko; Kozai, Naofumi; Wakai, Eiichi; Fujii, Tsutomu*; Iefuji, Haruyuki*; Francis, A. J.
Journal of Nuclear and Radiochemical Sciences, 6(1), p.99 - 101, 2005/07
We have carried out the growth experiments of 3 strains of yeast in a medium containing uranium (VI) to elucidate the effect of U (VI) on the growth of microorganisms. Hansenula fabianii J640 grew in the liquid medium containing 0.1 mM U (VI) at lower rate than the control, but Saccharomyces cerevisiae did not grow under this condition. The H. fabianii J640 pre-cultured for 21 h in the liquid medium without U (VI) grew even after the exposure to 1 mM U (VI), but did not grow without pre-cultivation. For the pre-cultured H. fabianii J640, radioactivity of U in the medium was the same as the initial one for 110 h, and then gradually decreased. TEM-EDS analysis of H. fabianii J640 exposed to 1 mM U (VI) for 165 h showed accumulation of U (VI) on the cells. When H. fabianii J640 was not pre-cultured, radioactivity of U in the medium was lower than the initial one. These results indicated that U (VI) inhibits the growth of yeast, and that the adsorption of U (VI) by the cells depends on the metabolism of yeast.
Murakami, Tsutomu; Hishida, Masahiko; Kisohara, Naoyuki; Hayafune, Hiroki; Hori, Toru; Fujii, Tadashi; Uchita, Masato; Chikazawa, Yoshitaka; Uno, Osamu; Saigusa, Toshiie; et al.
JNC TY9400 2004-014, 78 Pages, 2004/07
JNC-TY9400-2004-014.pdf:7.97MB
This report summarizes the results of the design study on the sodium-cooled large-scale reactor performed in JFY2003, which is the third year of Phase 2. In the JFY2003 design study, critical subjects related to safety, structural integrity and thermal hydraulics which found in the last fiscal year has been examined and the plant concept has been modified. Furthermore, fundamental specifications of main systems and components have been set and economy has been evaluated. In addition, as the interim evaluation of the candidate concept of the FBR fuel cycle is to be conducted, cost effectiveness and achievability for the development goal were evaluated and the data of the three large-scale reactor candidate concepts were prepared.
Hishida, Masahiko; Murakami, Tsutomu; Kisohara, Naoyuki; Fujii, Tadashi; Uchita, Masato; Hayafune, Hiroki; Chikazawa, Yoshitaka; Hori, Toru; Saigusa, Toshiie; Uno, Osamu; et al.
JNC TY9400 2004-012, 97 Pages, 2004/07
JNC-TY9400-2004-012.pdf:12.55MB
Based on the concept of a plant consisting of four modules with a capacity of 750 MWe each, which has been established by the end of FY2002, a concept of the entire plant was proposed, reflecting the modifications related to the high internal conversion type core, the double-wall straight tube steam generator (SG), and the fuel storage system. Concept studies were also performed to overcome the drawbacks of the sodium and to achieve in-service inspection and repair as easily as in light water reactor. Furthermore, feasibility studies were carried out to confirm the design, which included safety, thermal-hydraulics and the structures of the primary reactor auxiliary cooling system and the double-wall straight tube SG. A prospect for realization of this plant concept has been obtained through the evaluation results. In addition, as the interim evaluation of the candidate concepts of the FBR fuel cycle is to be conducted, cost effectiveness and achievability for the development goal were evaluated and the data of the three medium-scale reactor candidate concepts were prepared.
Konomura, Mamoru; Ogawa, Takashi; Okano, Yasushi; Yamaguchi, Hiroyuki; Murakami, Tsutomu; Takaki, Naoyuki; Nishiguchi, Youhei; Sugino, Kazuteru; Naganuma, Masayuki; Hishida, Masahiko; et al.
JNC TN9400 2004-035, 2071 Pages, 2004/06
JNC-TN9400-2004-035.pdf:76.42MB
The attractive concepts for Sodium-, lead-bismuth-, helium- and water-cooled FBRs have been created through using typical plant features and employing advanced technologies. Efforts on evaluating technological prospects of feasibility have been paid for these concepts. Also, it was comfirmed if these concepts satisfy design requierments of capability and performance presumed in the feasibilty study on commertialization of Fast Breeder Reactor Systems. As results, it was concluded that the selection of sodium-cooled reactor was most rational for practical use of FBR technologies in 2015.
Ono, Masao; Iguchi, Yusuke*; Bagum, R.*; Fujii, Kimio; Okayasu, Satoru; Mashimo, Tsutomu*
no journal, ,
We had realized atomic-scale graded structures in several miscible alloys by ultracentrifuge experiment. In this study, we performed an ultracentrifuge experiment on a MgCd order-disorder alloy at disordered state of solid solution. The experimental conditions were as follows: maximum acceleration: 610,000 g, temperature: 400C, composition: Mg:Cd=50:50at%, time duration: 60 h). We investigated the crystal state of the centrifuged sample that had ordered from the disorder state of atomic-scale graded structure. It was found that the graded structure was formed in the centrifuged sample, in which Cd content continuously increased in the direction of gravitational field. It was also found that the different peaks from the starting state appeared in X-ray diffraction patterns of the centrifuged sample. We will present details at the session.
Ono, Masao; Iguchi, Yusuke*; Bagum, R.*; Fujii, Kimio; Esaka, Fumitaka; Okayasu, Satoru; Mashimo, Tsutomu
no journal, ,
In this study, we performed an ultracentrifuge experiment on a MgCd order-disorder alloy at disordered state of solid solution. The experimental conditions were as follows: maximum acceleration: 610,000 g, temperature: 400C, composition: Mg:Cd=50:50at%, time duration: 60 h). We investigated the crystal state of the centrifuged sample that had ordered from the disorder state of atomic-scale graded structure. It was found that the graded structure was formed in the centrifuged sample, in which Cd content continuously increased in the direction of gravitational field. It was also found that the different peaks from the starting state appeared in X-ray diffraction patterns of the centrifuged sample.
Ono, Masao; Iguchi, Yusuke*; Okayasu, Satoru; Esaka, Fumitaka; Kobayashi, Katsura*; Hao, T.; Bagum, R.*; Osawa, Takahito; Fujii, Kimio; Nakamura, Eizo*; et al.
no journal, ,
The atomic-scale graded structure of In-Pb alloy was formed by an ultracentrifuge experiment under conditions that a gravitational field of 0.8110G for 100 hours at 150 C in solid state in our previous study. The isotope ratio measurements were performed on the centrifuged sample with secondary ion mass spectrometer (SIMS, CAMECA IMS-6f). Both In/In and Pb/ isotope ratio changed with negative gradient in the direction of centrifugal force approximately 1.2% showing the tendency that the heavy In isotope (Pb isotope) abundance increased and light In isotope (Pb isotope) abundance decreased in the direction of centrifugal force. This showed that the isotope fractionation effect due to sedimentation of atoms occurred in this alloy by ultracentrifuge experiment.
Kato, Yoshiyuki; Kurita, Tsutomu; Matsumoto, Masaki; Suzuki, Masahiro; Ishii, Katsunori; Yamamoto, Takuma; Kihara, Yoshiyuki; Yoshimoto, Katsunobu; Fujii, Kanichi
no journal, ,
An earlier accomplishment of FBR(fast breeder reactor) fuel cycle is the supreme subject from the point of view on the protection of environment by suppressing the green house effect as well as saving the oil. Microwave heating (MH) is employed as the MOX (mixed oxides U-Pu) production process in the main stream of FBR cycle. Thus, we are the optimization of MH method. We will describe the practical work of MOX fuel production which recycles the consumed nuclear fuel containing both U and Pu. The MH is employed to solidify the mixed solution by evaporating nitric acid and water. We call this processing de-nitration. The physical, mechanical, and chemical characteristics of the products are analyzed, being thereby discussed the contribution of the MH technology to the MOX fuel production. And, optimization of MH is discussed from the view point of design of MH oven, regulation of MH power, and combination with several auxiliary heating sources.
Suzuki, Masahiro; Ishii, Katsunori; Kihara, Yoshiyuki; Kurita, Tsutomu; Yoshimoto, Katsunobu; Okita, Takatoshi; Kashimura, Motoaki; Kato, Masato; Namekawa, Takashi; Fujii, Kanichi
no journal, ,
In FaCT project, we have set major six technologies for success of simplified pellet fuel fabrication. Our schedule on the technical fundamental technology should be completed by 2010, being transferred to the development of a technology for tele-command operation of mass production and facility maintenance until 2015. In this time, we will report current states of FaCT project as well as future plan.
Sakamoto, Fuminori; Onuki, Toshihiko; Fujii, Tsutomu*; Iefuji, Haruyuki*
no journal, ,
In this study, we cultured Saccharomyces cerevisiae in media containing Pb or U with adjusted concentration and compared influence of Pb and 4U on the growth of S. cerevisiae. S. cerevisiae grew in media containing 1 10
or 1 10 M Pb, but did not grow in the medium containing 1 10 M Pb. S. cerevisiae did not grow in the medium containing 1 10 and 1 10 M U. These results indicated that inhibitory effect of U on the growth of S. cerevisiae is greater than that of Pb and that Pb and U obstruct the growth of S. cerevisiae by a different mechanism. S. cerevisiae did not grow in the medium containing 1 10 M natural U, but grew in the medium containing U with alpha radioactivity equivalent to 1 10 M natural U. These results indicated that the growth of S. cerevisiae is not influenced by chemotoxicity but radiotoxicity of 1 10 M Pb and U.
Oka, Toshitaka; Yokoya, Akinari*; Fujii, Kentaro*; Kino, Yasushi*; Sekine, Tsutomu*
no journal, ,
The physicochemical processes of DNA by the K-shell photoabsorption of N and O atoms are unclear. To investigate those processes involved in DNA damage induction by irradiation, we developed an electron paramagnetic resonance (EPR) spectrometer installed in a synchrotron soft X-ray beamline BL23SU in SPring-8 and measured unstable intermediate species induced by selective inner-shell ionisation or excitation and subsequent Auger relaxation of particular atoms in pyrimidine DNA-bases. The EPR intensities for cytosine around the N and O K-edges were similar to the X-ray absorption near edge structure (XANES) spectra for around both K-edges, but the EPR intensities were 
2 times larger than the XANES spectra. The EPR intensities for pyrimidine DNA-bases seem to change with the substituent of the pyrimidine ring; maybe due to the substituent effect of the pyrimidine ring. In addition, the peak-to-peak line width of the EPR signals were also different by changing the substituent.
