Accuracy Spectrophotometric Determination of pH for Sea Water

准确分光光度法测定海水 pH 值

• 批准号: 05640555
• 负责人: YAMAZAKI Hideo
• 金额: $ 1.34万
• 依托单位: Kinki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05640555/
• 关键词: pH; Sea Water; pH Indicator; Spectrophotometric Method; Hydrogen Ion Concentration; 分光測光法; pH測定; 分光光度法

The pH of sea water was accurately determined from spectrophotometric measurement. The measurement of pH of the analyte solution was achieved by the spectrophotometric method using thymol blue as a pH indicator. Advantage was taken of the redundant data available with digitized spectra. The calculations of pH and its statistical errors were performed using the spreadsheet software. Statistically photometric errors of the pH measurement of sea water was estimated to be <plus-minus>0.00015 pH units. Because of limited by errors in the K_a evaluation of thymol blue, the overall accuracy of this method was <plus-minus>0.00072 pH at 25ﾟC,and salinities between 0 to 40 *. One aspect of pH measurement often ignored is the low reliability of glass electrode pH reading at high ionic strength sample. The use of spectral method can circumvent some of the difficulties. Accurate and reliable determination of the pH of sea water is necessary for the reveal of chemical process in the ocean. Currently, I am extending this approach to development of a new optical pH sensor.

通过分光光度测量准确测定分析物溶液的 pH 值，利用百里香酚蓝作为 pH 指示剂，利用数字化光谱的冗余数据来实现 pH 值的计算。由于受到限制，海水 pH 测量的统计光度误差估计为 <正负>0.00015 个 pH 单位。由于百里酚蓝的 K_a 评估存在误差，在 25℃、盐度在 0 到 40 之间时，该方法的总体准确度为 <正负>0.00072 *。 pH 测量经常被忽视的一个方面是玻璃电极的低可靠性。高离子强度样品的 pH 读数可以克服一些困难，准确可靠地测定海水的 pH 值对于揭示海洋中的化学过程是必要的。目前，我正在将这种方法扩展到新型光学 pH 传感器的开发。

项目成果

山崎秀夫: "分光測光法による新しい水素イオン濃度(pH)測定法の開発" 放射線科学. (印刷中).

Hideo Yamazaki：“开发一种使用分光光度法测量氢离子浓度 (pH) 的新方法”《放射科学》（正在出版）。

Hideo Yamazaki: "Development of New Method for Hydrogen concentration (pH) Measurements by Spectrophotometry (in Japanese)" Radiological Sciences. (in press).

Hideo Yamazaki：“开发分光光度法测量氢浓度 (pH) 的新方法（日语）”放射科学。

Hideo Yamazaki: "Spectrophotometric determination of the dissociation constant(pKa)of arsenous acid" Analytica Chimica Acta. (印刷中).

Hideo Yamazaki：“亚砷酸解离常数 (pKa) 的分光光度测定”Analytica Chimica Acta（出版中）。

Hideo Yamazaki: "Spectrophotometric determination of the dissociation constant(pKa) of arsenous acid" Analytica Chimica Acta. 284. 379-384 (1993)

Hideo Yamazaki：“亚砷酸解离常数（pKa）的分光光度测定”《分析化学学报》。

Hideo Yamazaki: "Spectrophotometric Determination of the Dissociation Constant (pK_a) of Arsenous Acid." Anal.Chim.Acta. 284. 379-384 (1993)

Hideo Yamazaki：“亚砷酸解离常数 (pK_a) 的分光光度测定。”