Studies of the Synthetic Inorganic Ion Exchanger. II : The Properties of Stannic Phosphate

A recommended procedure for the preparation of stannic phosphate and a discussion of its ion exchange properties have been presented. The stannic phosphate, the density of which is 2.17 g/cm^3, is a weakly acidic cation exchanger and possesses several dissociable hydrogen atoms in the range of pKa values. In a weakly acidic solution, in which the exchanger is useful, the exchange group having the pKa value of approximately three is most important. The ion exchange equilibrium can be elucidated by the mass action law and the affinity series for alkali metals coincides with the usual relationship observed in the ion exchange resin. The rate-determining step in the ion exchange is assumed to be the migration of ions through the water retained in the gel structure. From the data of thermal decomposition curve, ion exchange capacity, pH titration curves and mutual separation of alkali metals, the stability against heat treatment and γ-ray irradiation is estimated ; that is, the separation of alkali metals does not go well with the exchanger dried at 110℃ due to the slow rate of exchange, but the exchanger is stable against irradiation of about 10^9r and undergoes only a slight decrease in ion exchange capacity even when it is treated in water at 250℃ for 8 days. The structure has been suggested on the basis of above results and X-ray diffraction patterns

The Chemistry of Protactinium. II : The Behavior of Pentavalent Protactinium in a Perchloric Acid Solution

Studies of the chemical behavior of protactinium (V) were carried out with the TTA-benzene extraction method, the ion exchange method and the filtration method. When the protactinium concentration is less than 10^M and the perchloric acid concentration is 0.3-2.0N, the reaction of TTA extraction may proceed as : PaO_m(OH)_n^+4HT⇄Pa(OH)T_4+(m+n-1)H_2O+(5-2m-n)H^+ where 2m+n is 3 and 4, or as : PaO_m(OH)_nT^+4HT⇄PaT_5+(m+n)H_2O+(4-2m-n)H^+ where 2m+n is 2 and 3. The cation exchange experiment gives results consistent with this conclusion. On the other hand, when the concentration of protactinium is higher than 10^M, the above relation does not hold, even in the 5N perchloric acid solution, because protactinium forms the aggregates to a great extent. This has been confirmed by the filtration experiment

Studies of the Synthetic Inorganic Ion Exchanger. V. : The Separation of Zirconium-95 and Niobium-95 by Means of a Stannic Phosphate Cation Exchanger

With the aim of developing a method for the separation of ^Zr and ^Nb, various eluants were investigated, a sulfuric acid solution was found to be most suitable for this purpose. After the stannic phosphate exchanger column had been conditioned with 1N nitric acid, the sample solution was passed through it to adsorb ^Zr and ^Nb. By using a 2N sulfuric acid solution and a 3N sulfuric acid -0.01N hydrofluoric acid solution as eluants, ^Zr and ^Nb could be eluted respectively. The separation was not quantitative, however, because of the unfavorable tailing of the elution curves. On the basis of the above results, the possibility of the total radiochemical separation of a long-lived fission product and the mechanism of the adsorption of these ions were discussed

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絵画テキストは，画題（物語，説話，仏典など）を文字テキストとは異なる独自の方法で語っている。しかし，絵画テキストは中学校国語科の古典学習において，物語や説話などの文字テキストを読むための補足資料としてのみ用いられている。そこで，本稿では，『徒然草』第53段「是も仁和寺の法師」を画題として描いた，原本住吉如慶筆・飯塚円貞広美模写『徒然草絵巻』（金沢文庫所蔵）と英一蝶筆『御室法師図』（個人所蔵）の語り（＝〈絵語り〉）を読み解く活動の実践を報告し，中学校国語科の古典学習における絵画テキストの活用を提案したい