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JAEA Reports

Development of tailor-made adsorbents for uranium recovery from seawater on the basis of uranyl coordination chemistry (Contract research); FY2021 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tokyo Institute of Technology*

JAEA-Review 2022-028, 54 Pages, 2022/11

JAEA-Review-2022-028.pdf:2.97MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2021. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "Development of Tailor-made Adsorbents for Uranium Recovery from Seawater on the Basis of Uranyl Coordination Chemistry" conducted from FY2019 to FY2021. Since the final year of this proposal was FY2021, the results for three fiscal years were summarized. The present study aims to develop a new ligand class for efficient and selective capture of uranium from seawater. On the basis of deep understanding on uranyl coordination chemistry, we design molecular structures of pentadentate ligands as functional moieties for uranium adsorption from seawater and study fundamental coordination chemistry of uranyl ion with those ligands in order to resolve current problems in uranium recovery technology …

Journal Articles

Evolution of the reaction and alteration of granite with Ordinary Portland cement leachates; Sequential flow experiments and reactive transport modelling

Bateman, K.*; Murayama, Shota*; Hanamachi, Yuji*; Wilson, J.*; Seta, Takamasa*; Amano, Yuki; Kubota, Mitsuru*; Ouchi, Yuji*; Tachi, Yukio

Minerals (Internet), 12(7), p.883_1 - 883_20, 2022/07

 Times Cited Count:1 Percentile:0.02(Geochemistry & Geophysics)

JAEA Reports

Development of tailor-made adsorbents for uranium recovery from seawater on the basis of uranyl coordination chemistry (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tokyo Institute of Technology*

JAEA-Review 2021-041, 42 Pages, 2022/01

JAEA-Review-2021-041.pdf:2.03MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "Development of tailor-made adsorbents for uranium recovery from seawater on the basis of uranyl coordination chemistry" conducted in FY2020. On the basis of deep understanding on uranyl coordination chemistry, we design molecular structures of pentadentate ligands as functional moieties for uranium adsorption from seawater and study coordination chemistry of uranyl ion with those ligands in order to resolve current problems in uranium recovery technology from seawater and to develop novel selective and efficient adsorbents for this purpose.

Journal Articles

Evolution of the reaction and alteration of mudstone with ordinary Portland cement leachates; Sequential flow experiments and reactive-transport modelling

Bateman, K.; Murayama, Shota*; Hanamachi, Yuji*; Wilson, J.*; Seta, Takamasa*; Amano, Yuki; Kubota, Mitsuru*; Ouchi, Yuji*; Tachi, Yukio

Minerals (Internet), 11(9), p.1026_1 - 1026_23, 2021/09

 Times Cited Count:2 Percentile:22.02(Geochemistry & Geophysics)

JAEA Reports

Development of tailor-made adsorbents for uranium recovery from seawater on the basis of uranyl coordination chemistry (Contract research); FY2019 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tokyo Institute of Technology*

JAEA-Review 2020-026, 41 Pages, 2020/12

JAEA-Review-2020-026.pdf:3.25MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2019. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "Development of Tailor-Made Adsorbents for Uranium Recovery from Seawater on the Basis of Uranyl Coordination Chemistry". On the basis of deep understanding on uranyl coordination chemistry, we design molecular structures of pentadentate ligands as functional moieties for uranium adsorption from seawater and study coordination chemistry of uranyl ion with those ligands in order to resolve current problems in uranium recovery technology from seawater and to develop novel selective and efficient adsorbents for this purpose.

Journal Articles

Role of the hydroxo group in the coordination of citric acid to trivalent americium

Tamain, C.*; Bonato, L.*; Aupiais, J.*; Dumas, T.*; Guillaumont, D.*; Barkleit, A.*; Berthon, C.*; Solari, P. L.*; Ikeda, Atsushi; Guilbard, P.*; et al.

European Journal of Inorganic Chemistry, 2020(14), p.1331 - 1344, 2020/04

 Times Cited Count:3 Percentile:22.72(Chemistry, Inorganic & Nuclear)

The molecular characterization based on multi-technique approach has led to major highlights on revealing the coordination environment of americium (Am) surrounded by citric acid (H$$_{3}$$CitH). The structure of the different complexes at pH 1 and 3 are described. These characterizations are made possible by the comparison of the americium-citric acid system with the americium-tricarballylic acid (one analogue of the citric acid without the alpha-hydroxo group).

JAEA Reports

Development of neutron transport calculation codes for 3-D hexagonal geometry, 2; Improvement and enhancement of the MINISTRI code

Sugino, Kazuteru; Takino, Kazuo

JAEA-Data/Code 2019-011, 110 Pages, 2020/01

JAEA-Data-Code-2019-011.pdf:3.37MB

A deterministic discrete ordinates method (SN method) transport calculation code for three-dimensional hexagonal geometry has been developed as the MINISTRI code (Ver. 7.0). MINISTRI is based on the triangle-mesh finite difference method, which can perform neutron transport calculations with high accuracy for cores of fast power reactors and assemblies of the Russian BFS critical facility. The present study has derived a proper scheme for remarkably improving the convergence of MINISTRI by investigating the issue of previous MINISTRI (Ver. 1.1), which sometimes plays a poor convergence performance in calculations for large-scale power reactor cores. The verification test of improved MINISTRI has been carried out for various cores by setting the reference result as the multi-group Monte-Carlo calculation with the same cross-sections as used in MINISTRI. As a result, it is found that the agreements are within 0.1% for eigenvalues and within 0.7% for power distributions. Thus, the satisfying accuracy of MINISTRI has been confirmed. In order to reduce the calculation time, the initial diffusion calculation scheme and the parallel processing have been implemented. As a result, the calculation time is reduced to the approximately one tenth compared with previous MINISTRI. Furthermore, adoption of the treatment of the anisotropic cell streaming effect, preparation of the perturbation calculation tool, implementation of the function for specification of the triangle-mesh-wise material and merging of the hexagonal-mesh calculation code MINIHEX have been carried out. Thus, the versatility of MINISTRI has been enhanced.

Journal Articles

Altitudinal characteristics of atmospheric deposition of aerosols in mountainous regions; Lessons from the Fukushima Daiichi Nuclear Power Station accident

Sanada, Yukihisa; Katata, Genki*; Kaneyasu, Naoki*; Nakanishi, Chika*; Urabe, Yoshimi*; Nishizawa, Yukiyasu*

Science of the Total Environment, 618, p.881 - 890, 2018/03

 Times Cited Count:22 Percentile:61.95(Environmental Sciences)

Although the reconstruction of atmospheric deposition processes of radiocesium during the Fukushima Daiichi Nuclear Power Station (FDNPS) accident is essential, the whole picture of the deposition mechanism in complex topography has not been well understood yet. To understand atmospheric deposition processes of aerosols over the complex mountainous topography, we analyzed altitudinal characteristics of radiocesium released during the accident. At five selected mountainous areas in the eastern Japan, altitudinal characters of air dose rate observed by our high-resolution airborne surveys after the accident was analyzed based on the results of three typical (dry, wet, and cloud water) deposition obtained from the latest atmospheric dispersion.

Journal Articles

Reliability estimation of neutron resonance thermometry using tantalum and tungsten

Kai, Tetsuya; Hiroi, Kosuke; Su, Y. H.; Shinohara, Takenao; Parker, J. D.*; Matsumoto, Yoshihiro*; Hayashida, Hirotoshi*; Segawa, Mariko; Nakatani, Takeshi; Oikawa, Kenichi; et al.

Physics Procedia, 88, p.306 - 313, 2017/06

 Times Cited Count:4 Percentile:84.9(Instruments & Instrumentation)

Journal Articles

Simulation of phase modulation for longitudinal emittance blow-up in J-PARC MR

Yamamoto, Masanobu; Ezura, Eiji*; Hara, Keigo*; Hasegawa, Katsushi*; Nomura, Masahiro; Omori, Chihiro*; Schnase, A.*; Shimada, Taihei; Takagi, Akira*; Takata, Koji*; et al.

JPS Conference Proceedings (Internet), 8, p.012015_1 - 012015_6, 2015/09

The J-PARC MR provides a coasting proton beam for nuclear physics experiments by slow extraction. The longitudinal emittance should be enlarged until the MR flat top to mitigate the microwave instability. We have investigated a Phase Modulation (PM) method by using a High Frequency Cavity (HFC) to increase the emittance. We have performed extensive simulation studies to find the appropriate parameters of the PM through the particle tracking simulation. We found that the effective HFC frequency has linear dependence with the PM frequency, where the emittance is smoothly enlarged. Furthermore, we found that the required HFC voltage is inverse proportional to the square root of the duration time of the PM. These PM properties will be used for the design of the HFC. We describe the particle tracking simulation results of controlled emittance blow-up by the PM.

Journal Articles

Exploring of peptides with affinity to HER2 from random peptide libraries using radioisotope; Random hexapeptide libraries with fixed amino acid sequence at 1 and 2 positions

Sasaki, Ichiro; Hanaoka, Hirofumi*; Yamada, Keiichi*; Watanabe, Shigeki; Sugo, Yumi; Ohshima, Yasuhiro; Suzuki, Hiroyuki; Ishioka, Noriko

Peptide Science 2014, p.257 - 260, 2015/03

Journal Articles

Endohedral clusterization of ten water molecules into a "molecular ice" within the hydrophobic pocket of a self-assembled cage

Yoshizawa, Michito*; Kusukawa, Takahiro*; Kawano, Masaki*; Ohara, Takashi; Tanaka, Ichiro*; Kurihara, Kazuo; Niimura, Nobuo*; Fujita, Makoto*

Journal of the American Chemical Society, 127(9), p.2798 - 2799, 2005/03

 Times Cited Count:264 Percentile:97.15(Chemistry, Multidisciplinary)

An adamantanoid (H$$_{2}$$O)10 cluster is formed within the hydrophobic cavity of a self-assembled coordination cage. This cluster is termed "molecular ice" because it is the smallest unit of naturally occurring Ic-type ice. X-ray structural analysis, coupled with neutron diffraction study, reveals that the molecular ice is formed not by a simple space-filling effect but by efficient molecular recognition within the cage via H$$_{2}$$O:...pi interaction.

Journal Articles

Edge safety factor at the onset of plasma disruption during VDEs in JT-60U

Sugihara, Masayoshi; Lukash, V.*; Khayrutdinov, R.*; Neyatani, Yuzuru

Plasma Physics and Controlled Fusion, 46(10), p.1581 - 1589, 2004/10

 Times Cited Count:12 Percentile:37.27(Physics, Fluids & Plasmas)

Detailed examinations of the value of the edge safety factor q at the onset of thermal quench during intentional VDE experiments in JT-60U are performed using two different reconstruction methods, FBI/FBEQU and DINA. Results by both methods are very similar and show that the thermal quench occurs when the q value is in the range between 1.5-2. This result suggests that the predictive simulations for VDEs should be performed within this range of q to examine the subsequent differences in the halo currents, plasma movement and other plasma behavior during the current quench.

JAEA Reports

Development of cavity length control system for high repetition rate Nd:YAG laser oscillator (Joint research)

Maruyama, Yoichiro; Kubomura, Hiroyuki*; Kasamatsu, Tadashi*; Matsuoka, Shinichi*; Nakano, Fumihiko*; Kan, Hirofumi*

JAERI-Tech 2004-056, 14 Pages, 2004/09

JAERI-Tech-2004-056.pdf:3.49MB

A high average power tunable solid state laser is pumped by the second harmonic of LD-pumped high repetition rate Nd:YAG laser consisting of a single-longitudinal-mode oscillator and amplifiers. To operate the Nd:YAG laser oscillator with a single-longitudinal-mode by injection seeding, the cavity length control is required to coincide the resonant frequency of Nd:YAG laser oscillator with the frequency of seeder. For this purpose, a cavity length control system of the Nd:YAG laser oscillator is developed and the characteristics are studied. With this system, the cavity length is controlled at the pulse repetition rate of 0.5 kHz and the single frequency operation for more than three hours is realized.

Journal Articles

A Linear gyrokinetic model in magnetic coordinates

Jolliet, S.*; Angelino, P.*; Bottino, A.*; Idomura, Yasuhiro; Villard, L.*

Theory of Fusion Plasmas, ISPP21, p.345 - 351, 2004/00

Global particle-in-cell (PIC) simulations are a very useful tool for studying the time evolution of turbulence induced by ion-temperature-gradient (ITG) instabilities. Unfortunately, the linear code LORB5 and its non-linear version ORB5 require high computational power. In order to study more sophisticated models, we need to optimize these codes. We will focus on LORB5, which uses a cylindrical grid (r,z) for solving the Vlasov equation and a (s,$$theta$$) grid for the Poisson equation. The approach presented in this work consists of implementing the gyrokinetic model using a single (s,$$theta_*$$) grid. Here $$theta_*$$ is the straight-field-line poloidal coordinate. A method to avoid the singularity at the magnetic axis is presented, and a benchmark with the CYCLONE case is shown.

Journal Articles

Examinations on plasma behaviour during disruptions on existing tokamaks and extrapolation to ITER

Sugihara, Masayoshi; Lukash, V.*; Kawano, Yasunori; Yoshino, Ryuji; Gribov, Y.*; Khayrutdinov, R.*; Miki, Nobuharu*; Omori, Junji*; Shimada, Michiya

Proceedings of 30th EPS Conference on Controlled Fusion and Plasma Physics (CD-ROM), 4 Pages, 2003/07

We examine plasma behaviours during plasma disruptions in detail in JT-60U and other tokamaks to derive appropriate physics guidelines for the behaviours. Their interpretations and their extrapolations to ITER are incorporated into the DINA code, which solves plasma transport and 2D free boundary plasma equilibrium simultaneously with circuit equations for the vacuum vessel and the PF coils. Sensitivity of the plasma behaviours and their impact on the EM force during disruptions due to the range of variation and uncertainty of the experimental data are examined.

Journal Articles

Photodissociation of acetaldehyde, CH$$_{3}$$CHO$$rightarrow$$CH$$_{3}$$+HCO; Direct ab initio molecular dynamics study

Kurosaki, Yuzuru; Yokoyama, Keiichi

Chemical Physics Letters, 371(5-6), p.568 - 575, 2003/04

 Times Cited Count:31 Percentile:69.39(Chemistry, Physical)

A total of 400 trajectories for the photodissociation, CH$$_{3}$$CHO$$rightarrow$$CH$$_{3}$$+HCO, on the T$$_{1}$$ potential surface have been calculated using the direct ab initio molecular dynamics method at the UB3LYP/cc-pVDZ level of theory. It was predicted that the product CH$$_{3}$$ is neither vibrationally nor rotationally excited and HCO is vibrationally not excited but rotationally excited. The averaged HCO rotational energy was calculated to be 1.1 kcal/mol, which is 15.1 % of the available energy, 7.3 kcal/mol. The present result agrees with experiment within just a few percent of the observed data.

JAEA Reports

Cation-cation interaction in neptunyl(V) compounds

Krot, N. N.*; Saeki, Masakatsu

JAERI-Review 2003-005, 37 Pages, 2003/03

JAERI-Review-2003-005.pdf:2.12MB

The original manuscript was prepared by Professor N. N. Krot of Institute of Physical Chemistry, Russian Academy of sciences, in 1997. Saeki tried to translate that into Japanese and to add some new data since 1997. The contents include the whole picture of cation-cation interactions mainly on 5-valence neptunium compounds. Firstly, characteristic structures are summarized for the cation-cation bonding in compounds of neptunium. Secondly, it is introduced how the cation-cation bonding affects physical and chemical properties of the compounds. Then, detection-methods are shown for the cation-cation bonding in the compounds. Besides, the cation-cation interaction are shortly reviewed for compounds of other actinide-ions.

JAEA Reports

A High repetition rate, single-frequency Nd:YAG laser oscillator and its characteristics

Maruyama, Yoichiro; Oba, Masaki; Kato, Masaaki

JAERI-Tech 2002-004, 13 Pages, 2002/02

JAERI-Tech-2002-004.pdf:3.65MB

For the in-situ measurement of various substances in the atmosphere by using DIAL (Differential Absorption LIDAR) , a high repetition rate tunable laser is required to obtain data within a few seconds. As the pump source of the tunable laser, the performance of high repetition rate and high average power is indispensable. For the generation of high quality laser radiation, a laser oscillator with 1 kHz pulse repetition rate is made and seeded with very narrow linewidth single-longitudinal mode laser radiation from the outside of the oscillator cavity and its characteristics are studied. As the results, after the thermal equilibrium of the oscillator laser crystal, a single-longitudinal and near TEMoo transverse mode are realized at the pulse repetition rate between 0.5kHz and 1kHz. Single frequency operation is preserved by controlling the cavity length. The average output power of 3W (3mJ per pulse) is obtained. It is confirmed that this oscillator has enough performance as a oscillator of MOPA (Master Oscillator Power amplifier) system.

Journal Articles

Longitudinal beam dynamincs on 3 GeV PS in JAERI-KEK joint project

Yamamoto, Masanobu; Tamura, Fumihiko; Ezura, Eiji*; Hashimoto, Yoshinori*; Mori, Yoshiharu*; Omori, Chihiro*; Schnase, A.*; Takagi, Akira*; Uesugi, Tomonori*; Yoshii, Masahito*

Proceedings of 8th European Particle Accelerator Conference (EPAC 2002), p.1073 - 1075, 2002/00

Longitudinal beam emittance should be controlled to alleviate space charge effects by rf manipulations at 3 GeV proton synchrotrons in JAERI-KEK Joint High Intensity Proton Accelerator Project. At injection, bunching factor of 0.4 will be achived by controlled longitudinal beam painting and multiplying 2nd higher harmonics. Furthermore, heavy beam loading is a severe problem, and it should be compensated by feedforward method for stable acceleration. About these themes, the scenario will be described with particle tracking simulations.

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