A Cell Design for Minimizing iR Error in Controlled-Potential Polarography of High Specific Resistance Solutions
作者:
W. L. Belew,
D. J. Fisher,
M. T. Kelley,
J. A. Dean,
期刊:
Instrumentation Science & Technology
(Taylor Available online 1970)
卷期:
Volume 2,
issue 3
页码: 297-308
ISSN:1073-9149
年代: 1970
DOI:10.1080/10739147008543284
出版商: Taylor & Francis Group
数据来源: Taylor
摘要:
A design is presented for a polarographic cell that minimizes the iR error in controlled-potential polarography of solutions possessing a high specific resistance. A sharpened Smoler 90° vertical orifice DME is used. With this electrode, the mercury drop grows principally in the downward direction. This and the fact that the end of the capillary is sharpened to a point allows the positioning of a micro reference electrode probe directly above the mercury drop and to within 0.1 of the maximum radius of the mercury drop from the mercury surface during the entire drop life time. With this apparatus it is also possible to observe the iR error as a function of the distance between the reference electrode tip and the mercury drop surface. The effect of reference electrode position on iR error introduced is illustrated by a series of uranium and cadmium polarograms in high specific resistance media. Controlled-potential polarograms with little distortion attributable to iR error can be obtained with this cell design in solutions with specific resistances up to at least 22,000 Ω-cm.
点击下载:
PDF (520KB)
返 回