Nucleotide sequences of orthologs of the S-locus related gene, SLR1, in 20 species of Brassicaceae were determined and compared with the previously reported SLR1 sequences of six species. Identities of deduced amino-acid sequences with Brassica oleracea SLR1 ranged from 66.0% to 97.6%, and those with B. oleracea SRK and SLR2 were less than 62% and 55%, respectively. In multiple alignment of deduced amino-acid sequences, the 180-190th amino-acid residues from the initial methionine were highly variable, this variable region corresponding to hypervariable region I of SLG and SRK. A phylogenetic tree based on the deduced amino-acid sequences showed a close relationship of SLR1 orthologs of species in the Brassicinae and Raphaninae. Brassica nigra SLR1 was found to belong to the same clade as Sinapis arvensis and Diplotaxis siifolia, while the sequences of the other Brassica species belonged to another clade together with B. oleracea and Brassica rapa. The phylogenetic tree was similar to previously reported trees constructed using the data of electrophoretic band patterns of chloroplast DNA, though minor differences were found. Based on synonymous substitution rates in SLR1, the diversification time of SLR1 orthologs between species in the Brassicinae was estimated. The evolution and function of SLR1 and the phylogenetic relationship of Brassiceae plants are discussed.

To form Al-Sn alloys for bearing materials, molten salt electrolysis was performed in an AlCl 3 -NaCl-KCl molten salt containing SnCl 2 at 423 K. The voltammogram showed that the cathodic reduction of the Sn ions started at a potential of 0.5 V vs.Al/Al(III) in the molten salt showing that deposition of pure Sn was possible at 0.5 V.Co-deposition of Al and Sn occurred at potentials more negative than 0.1 V. The co-deposit was composed a solid solution of Al and Sn. The ratio of the Sn in the electrodeposits decreased with the potential from 100 at% at 0.2 V to 19 at% at -0.3 V.In the structural observations, electrodeposits with an alternate stacked structure of Al and Sn is obtained at -0.075V.

To develop an electrorefining process for sodium to enable recycling of used sodium-sulfur batteries, a non-aqueous electrolyte with low melting point was investigated. A mixed ionic liquid of NaTFSI (sodium bis(trifluoromethane)sulfonylimide) -TBATFSI (tetrabutylammonium bis(trifluoromethane)sulfonylimide) was selected for the electrolyte. From AC impedance measurements, a maximum ionic conductivity of 16 mS cm −1 was established of 20 mol% NaTFSI-TBATFSI concentration at 433 K. Electrorefining for 20 hours was carried out with a stable voltage under constant current electrolysis. Liquid pure sodium was electrodeposited by the constant current electrolysis. The calcium content in the sodium cathode was decreased from 250 to 52 ppm by the electrorefining.Metallic sodium is presently used as an intermediate (Sodium Alcoholate) in agricultural chemicals, 1 PCB decomposing agents (Sodium Dispersion), 2,3 and sodium-sulfur secondary batteries. 4,5 Presently, the sodium production has carried out only at a few countries in the world. Therefore, development of a process to circulate metallic sodium is highly desirable not only from resources recycling considerations. A process for electrowinning of sodium (Downs process) 6,7 produces metallic Na and Cl 2 gas from NaCl-CaCl 2 -BaCl 2 molten salts. The voltage of the electrolysis increases to exceed the decomposition voltage of NaCl during the electrolysis, and the electrical power consumption is known to be about 11000 kWh/t. In electrorefining to produce highly pure sodium from sodium containing impurities, the decomposition voltage is theoretically zero, and it may be assumed that the electrolysis voltage is not high. As a result it may be expected that the electric power consumption of the electrorefining process becomes less than the electrowinning process. However, no electrorefining process for sodium has been implemented on an industrial scale.In sodium-sulfur batteries where much sodium is contained, a large amount of metallic sodium remains in the batteries also in the used state. The sodium of about 400 kg is used for production of the sodium-sulfur batteries in every year. If metallic sodium is collected from used sodium-sulfur battery, electrorefining of the sodium may be carried out and resources of high purity sodium could be secured. And we believe that the development of electrorefining process becomes valuable technology in fields of high purity metal production.We have proposed a sodium recycling process which involves collection of the metallic sodium from used sodium-sulfur batteries and refining of the collected metallic sodium. [8][9][10] The electrorefining process of the metallic sodium from used Na-S batteries developed by us investigated organic solvents, molten salts, and ionic liquids as the electrolyte. From the results, it was found that an ionic liquid mixture of NaTFSI (sodium bis(trifluoromethane)sulfonylimide) -TBATFSI (tetrabuthylammonium bis (trifluoromethane)sulfonylimide) has a wide electrochemical potential window and that it displ...

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