22. 超音波照射時の水に対する溶存気体の影響
スポンサーリンク
概要
- 論文の詳細を見る
It is well known that H_2O_2, HNO_2 and HNO_3 are produced when power ultrasound is irradiated into water saturated with air. Several works have investigated the concentration dependence of the chemical species for the irradiation time. However, little study on the change in pH has been reported. Especially, the effect of the dissolved gases on the pH change is not cleared. The purpose of this work is to investigate quantitativety the pH change in water saturated with different gases under sonication. Sonication was carried out under atmosphere of air, oxygen, nitrogen, and argon. The value of pH in water for different dissolved gases was obtained under a constant ultrasonic intensity. The pH measurement was carried out by Expandable Ionanalyzer (Model EA 940, Orion). The ultrasonic intensity in a reaction vessel was determined on the basis of decomposition of porphyrin (tetraphenylporphine tetrasulfonic acid, hereafter abbreviated as TPPS). In this work, we pay sufficiently attention to degassing. Under air atmosphere, the pH value changed from 7 to 4.3 for irradiation time of 30 min and after that the value approached to 3.7. On the other hand, the pH values for water saturated with Ar, N_2 and O_2 were almost independent of irradiation time. In general, the decrease of pH in water saturated with air is considered to be responsible for production of HNO_3, since production of H_2O_2 and HNO_2 does not contribution to the change in the pH. On the other hand, in water saturated with only Ar or O_2, HNO_2 and HNO_3 should not be produced for lack of nitrogen. However, slightly decrease of the pH for Ar and O_2 was observed. The amounts of decomposed TPPS in solutions saturated with O_2 and air are two times as large as that saturated with N_2. In the case of Ar, the value is about three times as large as that for N_2. The ultrasonic effect on TPPS decomposition reaction for different dissolved gases is in the order of Ar > air = O_2 > N_2, which corresponds to that of the luminescence intensity.
- 日本ソノケミストリー学会の論文
- 1997-10-01
著者
関連論文
- P1-B-14 弾性表面波によるガラス基板上の高分子薄膜の物性評価(超音波物性・材料,ポスターセッション1(概要講演))
- P2-14 高分子複合材料の音波物性に及ぼす無機充填材の効果(ポスターセッション2,ポスター発表)
- PA18 表面波測定によるPAAゲルの物性評価(基礎・物性,ポスターセッション2)
- PA6 過冷却状態におけるテトラエチレングリコールの局所構造と構造緩和との相関(ポスターセッション2)
- PG9 超音波分解反応に対する反応容器体積の影響(ポスターセッション2)
- 21. シングルバブルソノルミネッセンスに対するアルコール添加効果(21)
- P2 単一気泡による化学作用の研究(ソノケミストリーの基礎科学)
- P16 円筒型超音波反応器のソノケミカル反応効率
- 21. シングルバブルによる化学作用 : 亜硝酸の生成反応
- 17. スチレンリビングラジカル重合に対する超音波照射効果の検討
- P-25 サーモグラフィーによる円筒型超音波反応器の評価(ポスターセッション)
- 3. フェノールフタレインを用いた超音波強度の簡易測定法の検討
- 20. スチレン重合に対する超音波周波数効果
- 22. 超音波照射時の水に対する溶存気体の影響