Polarography high-frequency

Bond and O Halloran42 claim for the combination of phase-selective detection and differential pulse ac polarography a "virtually complete rejection of ic, even at high frequencies and low concentrations . 

In connection with the square-wave technique, mention can be made of high-frequency polarography, also called radiofrequency polarography and developed by Barker53, in which a sinusoidal radio-frequency cu, (100kHz to 6.4 MHz) square-wave modulated at co2 (225 Hz) is superimposed on to the dc potential ramp as the wave form includes (apart from additional higher... 

Considerations of convenience and economy have led us to restrict the scope of this work in several ways. We have excluded electrochemical techniques, such as conductometry, high-frequency conductometry, and dielectro-metry,i, in which neither the electrical double layer nor any electrode reaction need be considered. These furnish information so widely different from, and so rarely used in conjunction with, that provided by polarography and its congeners that combining them would be difficult and of little use. 

Terminology related to electroanalytical chemistry are chronoamperometry, voltammetry, coulometry, amperometric titrimetry, coulometric titrimetry, conductivity, con-ductimetry and high frequency titrimetry, electrometric titrimetry, electrogravimetry, electrodeposition, anodic stripping voltammetry (ASV), cathodic stripping voltammetry (CSV), polarography, differentia] pulse polarography (DPP), ion-selective electrode (ISE), ion-specific electrode (ISE), molecular selective electrode, potentiometry, potentio-metric titrimetry, and chronopotentiometric titrimetry. 

Like zinc ions, cadmium ions can be titrated in buffered solutions with EDTA but the end-point is more easily located by high frequency titration than by an indicator. Among the instrumental methods suitable for the determination of cadmium in dilute solutions, atomic absorption is ideal and polarography is also suitable. Gravimetrically, cadmium can be precipitated as the oxinate similar to zinc. In addition, it can be precipitated as molybdate. 

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