• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Marine Chemistry >Physical-chemical characterization of purified cresol red for spectrophotometric pH measurements in seawater
【24h】

Physical-chemical characterization of purified cresol red for spectrophotometric pH measurements in seawater

机译：用于海水中分光光度法pH值测定的纯化甲酚红的理化特性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The use of impure cresol red in spectrophotometric seawater pH measurements can introduce systematic inaccuracies greater than 0.1. Cresol red has been purified on a bulk scale to address this problem, but a characterization of the dye's physical-chemical properties has not been provided to date. This work reports the physical-chemical characteristics of purified cresol red for use in spectrophotometric seawater pH measurements over a range of temperatures and salinities. Seawater pH is expressed on the total hydrogen ion concentration scale (pH_T) in terms of the ratio (R) of cresol red absorbances (A) at 433 and 573 nm (R_(Cr) = ~(573)A/_(433)A): PH_T = -log(K_2~Te_2)+log(R_(CR)-e_1/1-R_(CR e_3/e_2) where - log(K_2~Te_2) = a + b/T + c In T - dT a = -859.326051 +0.14616S + 7.81164 × 10~(-4)S~2 b = 22969.9366 + 8.04468S-0.20512S~2 c = 152.209523-0.0317821S d = 0.259915 and cresol red molar absorptivity ratios are expressed as: e_1 = -0.00413 + 1.814 × 10~(-5)T e_3/e_2 ==-0.021683 +1.8107 × 10~(-4)T + 3.163 × 10~(-5)(S-35) for 278.15 ≤ T ≤ 308.15 K and 20 ≤ S ≤ 40. We recommend using cresol red to measure the acidity of seawater that has (at 298.15 K) a pH_T of 6.8-7.8. This range might be encountered in ocean areas such as oxygen minimum zones or, hydrothermal vent fields, or it might be imposed in controlled laboratory studies. Ocean acidification will make cresol red an increasingly important indicator in coming decades as waters within ever larger ocean areas shift into its optimal indicating range.
机译：在分光光度法海水pH测量中使用不纯的甲酚红会引入大于0.1的系统误差。甲酚红已被大规模纯化以解决该问题，但是迄今为止尚未提供染料的物理化学性质的表征。这项工作报告了在温度和盐度范围内用于分光光度法海水pH测量中的纯化甲酚红的物理化学特性。海水pH以总氢离子浓度标度（pH_T）表示为在433和573 nm处的甲酚红吸光度（A）的比（R）（R_（Cr）=〜（573）A / _（433） A）：PH_T = -log（K_2〜Te_2）+ log（R_（CR）-e_1 / 1-R_（CR e_3 / e_2）其中-log（K_2〜Te_2）= a + b / T + c In T- dT a = -859.326051 + 0.14616S + 7.81164×10〜（-4）S〜2 b = 22969.9366 + 8.04468S-0.20512S〜2 c = 152.209523-0.0317821S d = 0.259915，甲酚红摩尔吸光度比表示为： e_1 = -0.00413 + 1.814×10〜（-5）T e_3 / e_2 ==-0.021683 +1.8107×10〜（-4）T + 3.163×10〜（-5）（S-35）对于278.15≤T≤ 308.15 K和20≤S≤40.我们建议使用甲酚红来测量pH_T为6.8-7.8的海水的酸度（在298.15 K时），在海洋区域（例如氧气最低限度区域或热液区域）可能会遇到该范围。海洋酸化将使甲酚红在未来几十年成为越来越重要的指标，因为水域中的海水会越来越大。 ean区域将移至其最佳指示范围。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号