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Journal Articles

Burial environment of bronze artifacts and behavior of bronze metal components at Yanagisawa archaeological site in Nagano Prefecture

Mitsui, Seiichiro; Murakami, Ryu*; Ueda, Norio*; Hirabayashi, Akira*; Hirota, Kazuho*

Bunkazai Kagaku, (77), p.1 - 14, 2018/10

Well-preserved bronze artifacts comprising five bells and eight halberds from the Yayoi Period were excavated at the Yanagisawa archaeological site in Nakano City, Nagano Prefecture in 2007. Comprehensive analysis of soil and groundwater samples at the site was carried out and geochemical calculations were made to better understand the local conditions that led to the artifacts being so well preserved. Analysis of the soil surface adjacent to the bronze artifacts identified cuprite (Cu$$_{2}$$O) as the main corrosion product. Migration behavior of the bronze metal components, copper, tin, and lead, both inside and outside of the burial pit, was also investigated. Copper and lead had migrated 2 m from the burial pit, whereas tin was confined to the immediate vicinity of the bronze artifacts. The difference in migration behavior of these elements can be explained in terms of the chemical stability of the solid phases. The main factor contributing to the well-preserved state of the bronze artifacts was the tin content, which is thought to have formed a protective layer of cassiterite (SnO$$_{2}$$) on the outer surface of the bronze artifacts.

JAEA Reports

Japan - IAEA Joint Nuclear Energy Management School 2016

Yamaguchi, Mika; Hidaka, Akihide; Ikuta, Yuko; Murakami, Kenta*; Tomita, Akira*; Hirose, Hiroya*; Watanebe, Masanori*; Ueda, Kinichi*; Namaizawa, Ken*; Onose, Takatoshi*; et al.

JAEA-Review 2017-002, 60 Pages, 2017/03


Since 2010, IAEA has held the NEM School to develop future leaders who plan and manage nuclear energy utilization in their county. Since 2012, JAEA together with Japan Nuclear HRD Network, University of Tokyo, Japan Atomic Industrial Forum and JAIF International Cooperation Center have cohosted the school in Japan in cooperation with IAEA. Since then, the school has been held in Japan every year. In 2006, Japanese nuclear technology and experience, such as lessons learned from the Fukushima Daiichi Nuclear Power Plant accident, were provided to offer a unique opportunity for the participants to learn about particular cases in Japan. Through the school, we contributed to the internationalization of Japanese young nuclear professionals, development of nuclear human resource of other countries including nuclear newcomers, and enhanced cooperative relationship with IAEA. Additionally, collaborative relationship within the network was strengthened by organizing the school in Japan.

Journal Articles

Progress in the geological disposal program in Japan

Deguchi, Akira*; Umeki, Hiroyuki*; Ueda, Hiroyoshi*; Miyamoto, Yoichi; Shibata, Masahiro; Naito, Morimasa; Tanaka, Toshihiko*

LBNL-1006984 (Internet), p.12_1 - 12_22, 2016/12

The H12 report demonstrated the feasibility of safe and technically reliable geological disposal in 1999. The Government of Japan re-evaluated the geological disposal program in terms of technical feasibility based on state-of-the-art geosciences and implementation process, because more than 10 years have passed from H12 and the Great Earthquake and nuclear accident have increased public concern regarding nuclear issues and natural hazards to cause accidents at nuclear facilities. Following the re-evaluation, the Government concluded further to promote geological disposal program, and thus the Basic Policy for Final Disposal was revised in 2015 including a new approach to siting process with identification of "Scientifically Preferable Areas". NUMO and relevant research organizations such as JAEA have been carrying out R and D activities to increase technical reliability for geological disposal. NUMO has started to develop a generic safety case.

JAEA Reports

Study on engineering technologies in the Mizunami Underground Research Laboratory (FY 2014); Development of recovery and mitigation technology on excavation damage (Contract research)

Fukaya, Masaaki*; Hata, Koji*; Akiyoshi, Kenji*; Sato, Shin*; Takeda, Nobufumi*; Miura, Norihiko*; Uyama, Masao*; Kaneda, Tsutomu*; Ueda, Tadashi*; Hara, Akira*; et al.

JAEA-Technology 2016-002, 195 Pages, 2016/03


The researches on examination of the plug applied to the future reflood test was conducted as a part of (5) development of technologies for restoration and/on reduction of the excavation damage relating to the engineering technology in the MIU (2014), specifically focused on (1) plug examination (e.g. functions, structure and material) and the quality control methods and (2) analytical evaluation of rock mass behavior around the plug through the reflood test. As the result, specifications of the plug were determined. These specifications should be able to meet requirements for the safety structure and surrounding rock mass against predicted maximum water pressure, temperature stress and seismic force, and for controlling the groundwater inflow, ensuring the access into the reflood gallery and the penetration performance of measurement cable. Also preliminary knowledge regarding the rock mass behavior around the plug after flooding the reflood gallery by installed plug was obtained.

Journal Articles

Progress of divertor simulation research toward the realization of detached plasma using a large tandem mirror device

Nakashima, Yosuke*; Takeda, Hisahito*; Ichimura, Kazuya*; Hosoi, Katsuhiro*; Oki, Kensuke*; Sakamoto, Mizuki*; Hirata, Mafumi*; Ichimura, Makoto*; Ikezoe, Ryuya*; Imai, Tsuyoshi*; et al.

Journal of Nuclear Materials, 463, p.537 - 540, 2015/08

 Times Cited Count:17 Percentile:88.2(Materials Science, Multidisciplinary)

Journal Articles

Development of divertor simulation research in the GAMMA 10/PDX tandem mirror

Nakashima, Yosuke*; Sakamoto, Mizuki*; Yoshikawa, Masayuki*; Oki, Kensuke*; Takeda, Hisahito*; Ichimura, Kazuya*; Hosoi, Katsuhiro*; Hirata, Mafumi*; Ichimura, Makoto*; Ikezoe, Ryuya*; et al.

Proceedings of 25th IAEA Fusion Energy Conference (FEC 2014) (CD-ROM), 8 Pages, 2014/10

Journal Articles

Sorption behavior of nickel and palladium in the presence of NH$$_{3}$$(aq)/NH$$_{4}$$$$^{+}$$

Kobayashi, Taishi*; Sasaki, Takayuki*; Ueda, Kenyo*; Kitamura, Akira

Materials Research Society Symposium Proceedings, Vol.1518, p.231 - 236, 2013/10

For the nuclear waste management of TRU waste, it is necessary to assess the impact of nitrate salts contained in the waste. In the present study, the sorption behavior of Ni and Pd on the pumice tuff was investigated in the presence of NH$$_{3}$$(aq)/NH$$_{4}$$$$^{+}$$. Under different NH$$_{3}$$(aq)/NH$$_{4}$$$$^{+}$$ concentration, pH and ionic strength conditions, distribution coefficient ($$K_{rm d}$$) of Ni and Pd on the pumice tuff was determined by batch experiment. For Ni system, the $$K_{rm d}$$ values showed no significant dependence on the initial NH$$_{4}$$$$^{+}$$ concentration in neutral pH region, agrees with the prediction from thermodynamic data. For Pd system, the $$K_{rm d}$$ values decreased with an increase of [NH$$_{4}$$$$^{+}$$]ini, suggesting the formation of stable ammine complex (Pd(NH$$_{3}$$)$$_{m}$$$$^{2+}$$ ($$m$$: 1 - 4)). The obtained $$K_{rm d}$$ values for Ni and Pd were analyzed using the surface complexation model. By taking complexes predicted by thermodynamic data into account, the sorption behavior of Ni and Pd in the presence of NH$$_{3}$$(aq)/NH$$_{4}$$$$^{+}$$ were well explained.

Journal Articles

Recent progress in the energy recovery linac project in Japan

Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05

Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.

Journal Articles

Burial environment of bronze halberds and bells excavated from Yanagisawa archaeological site in Nagano Prefecture

Murakami, Ryu*; Mitsui, Seiichiro; Hirabayashi, Akira*; Ueda, Norio*

Nihon Bunkazai Kagakkai Dai-26-Kai Taikai Kenkyu Happyo Yoshishu, p.108 - 109, 2009/07

Bronze halberds and bells in the Yayoi Period have been excavated from Yanagisawa archaeological site in Nakano City, Nagano Prefecture. This is the first case which both the artifacts were coincidentally excavated in eastern Japan and is important archaeological discovery. To identify the reason of good preservation of the artifacts, we analyzed soil and groundwater at the site as burial conditions. We also investigated migration behavior of copper, lead and tin as metal components derived from the artifacts in the surrounding soil. The results indicate that the preservation of the artifacts depends on the burial environment. In addition, we found that copper and lead migrated to the position of two meters from the pit buried the artifacts.

Journal Articles

Ultra-fast pulse radiolysis; A Review of the recent system progress and its application to study on initial yields and solvation processes of solvated electrons in various kinds of alcohols

Muroya, Yusa*; Lin, M.; Han, Z.*; Kumagai, Yuta; Sakumi, Akira*; Ueda, Toru*; Katsumura, Yosuke

Radiation Physics and Chemistry, 77(10-12), p.1176 - 1182, 2008/10

 Times Cited Count:14 Percentile:70.13(Chemistry, Physical)

In order to study radiation-induced fast phenomena, a new pulse radiolysis system with higher time resolution based on pulse-and-probe method was developed and utilized for practical work. A few picosecond electron beam generated from a linear accelerator, in which a laser photocathode RF-gun is introduced, was synchronized with a femtosecond laser pulse which is employed as the analyzing light. The synchronization precision between them was suppressed within 1.6 ps (rms). Converting the fundamental laser into white light continuum or optical parametric amplification allows to measure in the wide wavelength from visible to infrared region.

Journal Articles

Plasma physics and radiation hydrodynamics in developing an extreme ultraviolet light source for lithography

Nishihara, Katsunobu*; Sunahara, Atsushi*; Sasaki, Akira; Nunami, Masanori*; Tanuma, Hajime*; Fujioka, Shinsuke*; Shimada, Yoshinori*; Fujima, Kazumi*; Furukawa, Hiroyuki*; Kato, Takako*; et al.

Physics of Plasmas, 15(5), p.056708_1 - 056708_11, 2008/00

 Times Cited Count:106 Percentile:97.57(Physics, Fluids & Plasmas)

Journal Articles

A Novel non-intrusive resistance thermometer for sodium in fast breeder reactor

Yamasaki, Hiro*; Honda, Satoshi*; Ueda, Masashi; Endo, Akira*; Fueki, Manabu*

Keisoku Jido Seigyo Gakkai Rombunshu, 43(9), p.756 - 761, 2007/09

A non-intrusive temperature sensing system is proposed. It is developed for temperature measurement of liquid sodium coolant in fast breeder reactor. Liquid sodium is used as coolant due to high heat flux density in the reactor core. In this paper, the results of our feasibility study by 2-dimensional numerical simulation, small size experimental test done by Japan Atomic Energy Agency Oarai Institute, and theoretical analysis are described. The basic principle of temperature measurement is resistant thermometry of liquid sodium. The resistivity of liquid sodium is quite lower than that of the stainless steel (SUS304), which is used in the pipe wall. The resistivity temperature coefficient of liquid sodium(0.337%/deg) is higher than that of stainless steel(0.0865%/deg). If we feed electric current perpendicular to the axis of flow pipe, the current penetrates the pipe wall and flow across the liquid. The current concentrates the liquid sodium, only small portion of the current flows along the pipe wall. The electric potential distribution is almost dominated by resistivity of sodium. The potential distribution can be measured along the out side of the pipe wall. The potential difference between two fixed points on the pipe wall indicates the resistivity of sodium So the sodium temperature can be measured by potential difference. Measurement accuracy of $$pm$$5$$^{circ}$$C is obtained in experimental tests. Better estimation data are obtained by theoretical analysis using three dimensional model.

Journal Articles

Spiral spin structure in the Heisenberg pyrochlore magnet CdCr$$_2$$O$$_4$$

Matsuda, Masaaki; Takeda, Masayasu; Nakamura, Mitsutaka; Kakurai, Kazuhisa; Osawa, Akira*; Leli$`e$vre-Berna, E.*; Chung, J.-H.*; Ueda, Hiroaki*; Takagi, Hidenori*; Lee, S.-H.*

Physical Review B, 75(10), p.104415_1 - 104415_6, 2007/03

 Times Cited Count:41 Percentile:82.49(Materials Science, Multidisciplinary)

A frustrated spinel CdCr$$_2$$O$$_4$$ undergoes a three-dimensional spin-Peierls transition at $$T_N$$ = 7.8 K from a cubic paramagnetic to a tetragonal N$'e$el state. The N$'e$el state has a spiral magnetic structure with a characteristic wave vector of $$(0,delta,1)$$ when the $$c$$ axis elongated. Here we report our spherical neutron polarimetry experiments to investigate the spiral spin structure in detail. Our results indicate that the spins lie in the $$ac$$ plane perpendicular to the direction of the spiral modulation. We also found that the spiral structure in the $$ac$$ plane is elliptical with the $$c$$-component larger by $$sim$$24% than the $$a$$-component, suggesting a strong coupling between the magnetic structure and structural distortion. Unpolarized neutron diffraction under an external magnetic field has also been performed. The magnetic field dependence suggests existence of magnetic anisotropy in the N$'e$el state, which is consistent with our previous inelastic studies.

Journal Articles

Verification of the plant dynamics analytical code CERES using the results of the plant trip test of the prototype fast breeder reactor MONJU

Nishi, Yoshihisa*; Ueda, Nobuyuki*; Kinoshita, Izumi*; Miyakawa, Akira; Kato, Mitsuya*

Proceedings of 14th International Conference on Nuclear Engineering (ICONE-14) (CD-ROM), 10 Pages, 2006/07

CERES is plant system analysis code for LMRs developed by the Central Research Institute of Electric Power Industry (CRIEPI). CERES has a function of calculating multidimensional flow in the plena of a coolant in addition to that in one-dimensional plant network calculation. To verify the CERES code, analyses were performed by using the result of the plant trip test from the partial power operation of the prototype FBR "MONJU" that had been executed in December, 1995. The verification work was performed as a joint research of CRIEPI and JAEA. (1)Analysis concerning the primary/secondary/auxiliary cooling system (the plenum in the reactor vessel (R/V) is modeled in R-Z 2-dimension). (2)Analysis concerning the flow pattern in the plenum of R/V (the plenum is modeled in 3-dimension). (3)Analysis concerning the flow pattern inside the IHX plenum (the plenum in the IHX is modeled in 3-dimension). Analytical results by the CERES code showed good agreement with the results of the test of the "MONJU". Fundamental abilities of the CERES as a plant dynamics calculation code had been verified through these analyses. Additionally, some characteristic flows in plena of "MONJU" became clear by these analyses.

Journal Articles

Rhemium-186-monoaminemonoamidedithiol-conjugated bisphosphonate derivatives for bone pain palliation

Ogawa, Kazuma*; Mukai, Takahiro*; Arano, Yasushi*; Otaka, Akira*; Ueda, Masashi*; Uehara, Tomoya*; Magata, Yasuhiro*; Hashimoto, Kazuyuki; Saji, Hideo*

Nuclear Medicine and Biology, 33(4), p.513 - 520, 2006/05

 Times Cited Count:51 Percentile:80.77(Radiology, Nuclear Medicine & Medical Imaging)

To develop a radiopharmaceutical for the palliation of painful bone metastases based on the concept of bifunctional radiopharmaceuticals, we synthesized a bisphosphonate derivative labeled with rhenium-186 ($$^{186}$$Re) that contains a hydroxyl group at the central carbon of its bisphosphonate structure and attached a stable $$^{186}$$Re-MAMA chelate to the amino group of a 4-amino-butylidene-bisphosphonate derivative, $$^{186}$$Re-MAMA-HBP, and investigated the effect of a hydroxyl group at the central carbon of its bisphosphonate structure on the affinity for hydroxyapatite and biodistribution by conducting a comparative study with $$^{186}$$Re-MAMA-BP. $$^{186}$$Re-MAMA-HBP was prepared by a reaction with $$^{186}$$ReO$$_{4}$$$$^{-}$$ and SnCl$$_{2}$$ in citrate buffer after the deprotection of trityl groups of Tr-MAMA-HBP. After reversed phase HPLC, $$^{186}$$Re-MAMA-HBP had a radiochemical purity of over 95 %. Compared with $$^{186}$$Re-MAMA-BP, $$^{186}$$Re-MAMA-HBP showed a greater affinity for hydroxyapatite beads in vitro and accumulated a significantly higher level in the femur in vivo. Thus, the introduction of a hydroxyl group into $$^{186}$$Re complex-conjugated bisphosphonates would be effective in enhancing accumulation in bone. These findings provide useful information on the design of bone-seeking therapeutic radiopharmaceuticals.

Journal Articles

Low-density tin targets for efficient extreme ultraviolet light emission from laser-produced plasmas

Okuno, Tomoharu*; Fujioka, Shinsuke*; Nishimura, Hiroaki*; Tao, Y.*; Nagai, Keiji*; Gu, Q.*; Ueda, Nobuyoshi*; Ando, Tsuyoshi*; Nishihara, Katsunobu*; Norimatsu, Takayoshi*; et al.

Applied Physics Letters, 88(16), p.161501_1 - 161501_3, 2006/04

 Times Cited Count:63 Percentile:88.67(Physics, Applied)

no abstracts in English

Journal Articles

Electronic properties of transuranium compounds with HoCoGa$$_5$$-type tetragonal crystal structure

Maehira, Takahiro*; Hotta, Takashi; Ueda, Kazuo*; Hasegawa, Akira*

New Journal of Physics (Internet), 8(2), p.24_1 - 24_20, 2006/02

 Times Cited Count:16 Percentile:66.17(Physics, Multidisciplinary)

By using a relativistic band-structrue calculation method, we investigate energy band structures and the Fermi surfaces of NpTGa$$_5$$, PuTGa$$_5$$, and AmCoGa$$_5$$ with transition metal atoms T. It is found in common that the energy bands in the vicinity of the Fermi level are mainly due to the large hybridization between $$5f$$ and Ga $$4p$$ electrons. For PuTGa$$_5$$, we observe several cylindrical sheets of Fermi surfaces with large volume for T=Co, Rh, and Ir. It is also found that the Fermi surfaces of NpFeGa$$_5$$, NpCoGa$$_5$$, and NpNiGa$$_5$$ are similar to those of UCoGa$$_5$$, UNiGa$$_5$$, and PuCoGa$$_5$$, respectively, except for small details. For AmCoGa$$_5$$, the Fermi surfaces are found to consist of large cylindrical electron sheets and small closed hole sheets, similar to PuCoGa$$_5$$. The similarity is basically understood by a rigid-band picture.

Journal Articles

Opacity effect on extreme ultraviolet radiation from laser-produced tin plasmas

Fujioka, Shinsuke*; Nishimura, Hiroaki*; Nishihara, Katsunobu*; Sasaki, Akira; Sunahara, Atsushi*; Okuno, Tomoharu*; Ueda, Nobuyoshi*; Ando, Tsuyoshi*; Tao, Y.*; Shimada, Yoshinori*; et al.

Physical Review Letters, 95(23), p.235004_1 - 235004_4, 2005/12

 Times Cited Count:135 Percentile:95.53(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Measurement of emittance for electron bunches compressed by velocity bunching via double-slit-scan method

Iijima, Hokuto; Hajima, Ryoichi; Uesaka, Mitsuru*; Sakumi, Akira*; Sakamoto, Fumito*; Ueda, Toru*

Proceedings of 2nd Annual Meeting of Particle Accelerator Society of Japan and 30th Linear Accelerator Meeting in Japan, p.501 - 503, 2005/07

We report the availability of velocity bunching in an energy recovery linac (ERL) by a numerical analysis, and the plan of precise measurement of bunching emittance via a double-slit-scan method. The simulation performed for eight TESLA-type cavities reveals successful bunch compression from 3.2 ps to 0.17 ps. Since the residual energy spread after velocity bunching is considerably smaller than the correlated energy spread required for magnetic compression through a recirculation loop, velocity bunching is useful to realized short-pulse and high-brightness X-rays by ERL. The emittance of velocity bunching was calculated to be 1.5 $$pi$$mm.mrad for the bunch charge of 77pC without the emittance compensation by an external solenoid field. Although the emittance growth due to the space-charge effect was small in the simulation, it is necessary to evaluate the emittance-growth mechanism under velocity bunching. Therefore, the emittance measurement via double-slit-scan method is carrying out in the UTNL-18L.

JAEA Reports

Verification of the plant dynamics analytical code CERES using the results of the plant trip test of the Prototype Fast Breeder Reactor MONJU

Nishi, Yoshihisa*; Ueda, Nobuyuki*; Kinoshita, Izumi*; Miyakawa, Akira; Kato, Mitsuya*

JNC TY2400 2005-001, 66 Pages, 2005/06


Multi-dimensional thermal-hydraulic characteristic of the coolant in the reactor vessel (R/V) influences the temperature at the plant transitional condition of fast breeder reactor (FBR). CRIEPI is developing plant dynamics calculation code CERES for FBR that adds multi-dimensional thermal-hydraulic analysis function to one-dimensional system calculation code to evaluate the temperature distribution in high accuracy. The temperature distribution affects the integrity of equipments of FBR. To verify the CERES code, analyses were performed by using the result of the plant trip test from the partial power operation of the prototype fast breeder reactor

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