l-酸性グルタミン酸ナトリウムと食塩との混合物への宗差熱分析法の応用につき検討を行ない, つぎの結果を得た.
1.l-酸性グルタミン酸ナトリウム単独の示差熱曲線は140℃附近で脱水による吸熱ピークおよび220℃附近で融解による吸熱ピークを示し, 続いて分解による発熱を示す. この二つの吸熱ピーク面積と試料量との間には大体直線関係が認められた.
2.l-酸性グルタミン酸ナトリウムと食塩とを混合した場合に,l-酸性グルタミン酸ナトリウムの融解ピークは食塩量が増すにつれ不明瞭になり, とくに粉末試料ではこの傾向が強い. 脱水ピークはこの影響を比較的受けにくい.
3. そこで, 混合物中のl-酸性グルタミン酸ナトリウムの含有量と脱水ピーク面積との関係を利用して, 市販あじしお中のl-酸性グルタミン酸ナトリウムの定量を試み大体妥当な結果を得た.

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It is said that when sodium chloride is electrolyzed with a graphite electrode, the vanadium cont-ained in the electrode as an impurity gradually goes into the solution, and the vanadium ions result in an abnormal electrolysis (the decrease in current efficiency). Even the explosion of the cell sometimes occurs. Therefore, a precise and rapid analytical method is required to determine 5-10ppm vanadium contained in the electrode.
Recently, a detailed study was conducted in our laboratory on the use of diphenylaminesulphonate for the trace analysis of vanadium. As the reult, a method was developed which was good enough to be applied to the trace analysis of vanadium.
This sensitive spectrophotometric method for the determination of vanadium (V) is based upon the reaction of vanadium (V) with diphenylaminesulphonate in 0.65N sulfuric acid.
Two procedures have been investigated for the determination of vanadium in graphites. The first one involved the dry combustion of the graphite to ash followed by the disolution of the ash with sulfuric acid. The second one involved the wet digestion of the vanadium in graphites with sulfuric acid.
The two sulfuric acid solutions of vanadium obtained from the above methods were separately given a spectrophotometric analysis for vanadium (V). It was observed that the second procedure yielded erratic results for many graphite electrodes, while the first one yielded accurate and reaso-nably sensitive results for the determination of vanadium within the range of 0-100ppm.

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名古屋産花崗岩風化土にセメントを3～10%添加したソイルセメントに塩を1%添加した場合の突き固め試験と一軸圧縮試験ならびに乾燥-吸水試験を行なつた.
その結果 1) ソイルセメントに塩を添加すると, 最適含水比は減少するようになり, 最大乾燥密度は無添加に比して上昇する. 2) 圧縮強度は塩を添加すると顕著に増加する. 3) たとえば50kg/cm²の強度をうるためには無塩区では7.6%のセメント量が必要であるが, 塩を1%添加すれば所要強度をうるのにセメント量は4.8%でよい. 4) したがつて塩添加によりソイルセメソトに使用するセメント量が節約できて経済的である. 5) 塩を添加すると乾燥, 吸水による水分の移動が少い.

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In their previous papers (This Journal 14, 227-34 (1960); 15, 118-22 (1961)), the authors made a graphical calculation on the isothermal evaporation of natural gas brine at 25°C by means of equilibrium diagram of the five-components system, NaCl-KCl-MgCl₂-CaCl₂-H₂O.
In the present paper, the authors conducted an experimental study on the isothermal evaporation of synthetic gas brine for the purpose of verifying results obtained from the previous calculation. Four kinds of synthetic brines were prepared with pure chemicals, and several portions of each sample were evaporated in a thermostat with an electric fan. The crystaline precipitates from each portion were identified with X-ray diffration, and the compositions of the mother liquors were chemically analyzed. As the result, the crystals were found to correspond in kind of the results obtained from the previous calculation. The compositions of the mother liquor well coincided with the calculated values in the early stage of evaporation, but the coincidence became worse toward the end of the evaporation.

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Mixed salt is obtained in bittern factories during the process of evaporating sea-salt bittern at the boiling temperatures up to about 124°C, and it is used as a component of fertilizer and others, For such uses, the product should be aged for 15-40 days to be completely solidified.
The authors studied the mechanism of solidification for the purpose of finding out the way as to how to rationalize the process. This paper reports the results of studies which were conducted to investigate the crystalline composition by means of X-Ray diffraction by using several specimens produced after various aging times in Utatsu Kagaku Factory in Kagawa Prefecture and several specimens prepared in our laboratory by boiling synthetic bitterns.
As the result, all of the mixed salt specimens were found to mainly consist of the mixture of crystals of sodium chloride and langbeinite, some carnallite, and various hydrates of magnesium sulphate.
From these results, the authors concluded as follows:
(1) The crystalline composition of the mixed salt is mainly the mixture of crystals of sodium chloride and langbeinite.
(2) Although the composition of the mixed salt is usually indicated by the percentages of NaCl, KCl, MgSO₄, MgCl₂ and H₂O, it is considered preferable to indicate it by the percentages of NaCl, K₂SO₄, MgSO₄, MgCl₂ and H₂O, or more correctly by the percentages of NaCl, K₂SO₄·2MgSO₄, MgSO₄, MgCl₂ and H₂O.

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