Nuclear cycle

Nuclear criticality, preventing, 17 547 Nuclear cycle, water treatment issues in, 23 235-236... 

The SETFICS process (Solvent Extraction for Trivalent /-elements Intragroup Separation in CMPO-Complexant System) was initially proposed by research teams of the former Japan Nuclear Cycle Development Institute (JNC, today JAEA) to separate An(III) from PUREX raffinates. It uses a TRUEX solvent (composed of CMPO and TBP, respectively dissolved at 0.2 and 1.2 M in -dodecane) to coextract trivalent actinides and lanthanides, and a sodium nitrate concentrated solution (4 M NaN03) containing DTPA (0.05 M) to selectively strip the TPEs at pH 2 and keep the Ln(III) extracted by the TRUEX solvent (239). However, the DFs for heavy Ln(III) are rather poor. An optimized version of the SETFICS process has recently been proposed as an alternative process to extraction chromatography for the recovery of Am(III) and Cm(III) in the New Extraction System for TRU Recovery (NEXT) process. NEXT basically consists of a front-end crystallization of uranium, a simplified PUREX process using TBP for the recovery of U, Np, and Pu, and a back-end Am(III) + Cm(III) recovery step (240, 241). 

Laidler, J.J., Bresee, J.C. 2004. The U.S. Advanced Fuel Cycle Initiative Development of separations technologies. ATALANTE 2004 Advances for Future Nuclear Cycles, June, Nimes, France. 

Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA) considers tritium as one of the four volatile, hazardous radionuclides ( H, Kr, and 1) that are created in nuclear cycle with long-term risk... 

Hydroxides. Pure and mixed metal actinide hydroxides have been studied for their potential utility in nuclear fuel processing. At the other end of the nuclear cycle, the hydroxides are important in spent fuel aging and dissolution, and environmental contamination. Tetravalent actinides hydrolyze readily, with Th more resistant and Pu more likely to undergo hydrolysis than and Np. All of these ions hydrolyze in a stepwise marmer to yield monomeric products of formula An(OH) with = 1,2,3 and 4, in addition to a number of polymeric species. The most prevalent and well characterized are the mono- and tetra-hydroxides, An(OH) and An(OH)4. Characterization of isolated bis and tri-hydroxides is frustrated by the propensity of hydroxide to bridge actinide centers to yield polymers. For example, for thorium, other hydroxides include the dimers. 

The Japan Atomic energy Research Institue (JAERI) merged with the Japan Nuclear Cycle Development Institute... 

Organisation CRIEPI (Central Research Institute of Electric Power Industry), Hitachi (Hitachi Ltd), Toshiba (Toshiba Corporation), FES (Fuji Electric Systems Co.), INC (Japan Nuclear Cycle Development Institute), JAERI (Japan Atomic Energy Research Institute), MFH (Mitsubishi Heavy Industries, Ltd), ARTEC (Advanced Reactor Technology Co.), TGC (Tokyo Gas Co.), NSA (Nuclear Systems Association), Tokyo Tech (Tokyo Institute of Technology). 

A new thermochemical and electrolytic hybrid hydrogen production system in lower temperature range has been developed by the Japan Nuclear Cycle Development Institute (JNC) to achieve the hydrogen production from water by using the heat from a sodium cooled fast reactor (SFR) [7]. 

The thermochemical and electrolytic hybrid hydrogen production process has been developed by Japan Nuclear Cycle Development Institute (JNC). The process is based on sulfuric acid (H2SO4) syntliesis and decomposition process developed earlier (Westinghouse process) and sulfur trioxide (SO,) decomposition process is facilitated by electrolysis with ionic oxygen conductive solid electrolyte at 500°C-550°C. Stable hydrogen and oxygen production for several hours by the process was already confirmed in the experiments performed by JNC. 

A chopped irradiated fuel pin was transported to Alpha-Gamma Facility (AGF) of the Japan Nuclear Cycle Development Institute. The irradiated fuel was furtlicr sliced into pieces of 5 mm in length at AGF. 

Japan Nuclear Cycle Development Insititute, Japan... 

JNC. 2000. HI2 Project to Establish the Scientific and Technical Basis for HLW Disposal in Japan. Second progress report on research and development for the geological disposal of HLW in Japan. Five volumes. Japan Nuclear Cycle Development Institute (JNC). 

This model was verified by desiccation tests performed by the Japan Nuclear Cycle Development Institute (INC 1999) with compacted samples of bentonite/sand mixture. A reversed correlation was derived to ht f x) = (s. Example 1 in... 

INC. 1999. H12 project to establish the scientific and technical basis for HLW disposal in Japan. Technical Report Support Report 2, Japan Nuclear Cycle Development Institute. http //www.jnc.go.jp/kaihatu/tisou/zh 12/h 12/s02 /pdf/b-09.pdf. 

Japan Nuclear Cycle Development Institute (JNC) has already developed the coupled thermo -hydro and mechanical (T-H-M) model and has initiated a research on the coupled T-H-M-C processes to predict the chemical evolution of buffer material and porewater chemistry, and the chemical effects on other (thermal, hydraulic and mechanical) processes. In this research, numerical experiment system for the coupled T-H-M-C processes is developed in order to predict the longterm evolution of the near-field (engineered barriers and surrounding host rock) for various repository designs and geological environments. 

This chapter shows the coupled thermal, hydraulic and mechanical behavior in the near field by using THAMES that is the finite element simulator originally developed by Ohnishi et al (1985). It was applied to the near field mesh shown as Figure 2. The model domain is corresponding to the shaded area shown in Figure 1. It is assumed that tunnel interval is 10 m and pit interval is 4.4 m following the Japan Nuclear Cycle Development Institute H12 report (JNC(1999)). 

Ibaraki University, Japan Japan Nuclear Cycle Development Institute, Japan Hazama Corporation, Japan ) Kyoto University, Japan... 

Fig. 2 A, B. Comparison of the duplication cycle and morphology of A pre-divisional B post-divisional cells of A. m du/ans. A conidium (a) germinates and the first septum is formed at the basal end of the germ tube (b) when the germling has eight or more nuclei. Post-divisional cells are differentiated into subapical and apical tip cells (B). Apical cells contain many nuclei that are evenly spaced along the cell. Subapical cells contain three to four evenly spaced nuclei. Subapical cells can branch, and the branched cell grows like an apical cell. Apical and branched subapical cells have active nuclear cycles (filled circles) while nuclei in unbranched subapical cells are trapped in interphase (empty circles). (Revised from [37])...

Growth and Nuclear Cycle Operation in Single Cells of S. aerevisiae... 

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