Osteryoung square wave

One aspect that reflects the electronic configuration of fullerenes relates to the electrochemically induced reduction and oxidation processes in solution. In good agreement with the tlireefold degenerate LUMO, the redox chemistry of [60]fullerene, investigated primarily with cyclic voltammetry and Osteryoung square wave voltammetry, unravels six reversible, one-electron reduction steps with potentials that are equally separated from each other. The separation between any two successive reduction steps is -450 50 mV. The low reduction potential (only -0.44 V versus SCE) of the process, that corresponds to the generation of the rt-radical anion 131,109,110,111 and 1121, deserves special attention. 

Figure 41 Potential-time perturbation in Osteryoung Square Wave Voltammetry...

In this solvent, using CV and Osteryoung square-wave voltammetry (OSWV) under high vacuum conditions at room temperature, Cgo displays a one-electron, chemically reversible oxidation wave at +1.26 V vs. Fc/Fc+. TBAPFe was used as the supporting electrolyte. Under the same conditions, the first one-electron oxidation of C70 occurs at +1.20 V, 60 mV more negative (easier to oxidize) than that of Cgo- Both oxidations are electrochemically quasireversible with A pp = 80 mV. In addition, a second oxidation wave is observed for C70 close to the limit of the solvent potential window at+1.75 V. However, this wave appears to be chemically irreversible (see Fig. 3) [36]. 

CAImHPFJ Multiwalled carbon nanotube Carbon microfiber N/A Dopamine 18 X 10- to 180 X 10-6 NR Osteryoung square wave voltammetry 36 S) S)... 

Figure 8.1 Cyclic voltammetry (a) and Osteryoung square wave voltammetry (b) of Cgo (acetonitrile/toluene + 0.1 M ( -Bu)4NPF6), using a glassy carbon electrode (GCE) working and ferrocene/ferrocenium (Fc/Fc +) couple as an internal reference. Reprinted with Permission from Ref. 4. Copyright 1992 American Chemical Society.

Fig. 10.3. General electrochemical performance of MPA-Gly-Gly-His modified electrodes for the detection of Cu2+ ions. Cu2+ ions are complexed to Gly-Gly-His in the accumulation process and are electrochemically reduced to Cu(0) to give UPD Cu. (a) Cyclic voltammograms of MPA-Gly-Gly-His modified electrodes in 50 mM ammonium acetate (pH 7.0) and 50 mM NaCl at 25°C at a scan rate of lOOrnVs-1 (i) before accumulation of metal ions and (ii) after accumulation in 46 nM Cu2+ in 50 mM ammonium acetate (pH 7.0) for 10 min. Multiple cycles in the copper voltammogram illustrate stable electrochemistry, (b) Cathodic Osteryoung square wave voltammograms of MPA-Gly-Gly-His modified gold electrodes in 50 mM ammonium acetate (pH 7.0) and 50 mM NaCl (i) before accumulation of metal ions and (ii) after accumulation in 46 nM Cu2+ in 50 mM ammonium acetate (pH 7.0) for 10 min. Reprinted from Ref. [12]. Copyright (2005) with permission from Elsevier.

A. Golcu, S.A. Ozkan, Electroanalytical determination of donepezil HC1 in tablets and human serum by differential pulse and Osteryoung square wave voltammetry at a glassy carbon electrode, Pharmazie 61 (2006) 760-765. 

Osteryoung square-wave voltammetry — The protocol of square-wave voltammetry developed by - Osteryoung is based on a square-wave potential train with a frequency that for each forward potential pulse the DC electrode is stepped in the same direction by one increment, i.e., one step of the DC staircase ramp. 

The electrochemistry of the polymeric and isomorphous cobalt(II) and nickel(II) methylsquarates was also studied by Iwuoha et al. In aqueous solutions, they found evidence that both the nickel(II) methylsquarate and its cobalt analog were dissociated without any reversible redox processes occurring for the metal ions. However, the cyclic and Osteryoung square wave voltammograms, obtained using a Pt electrode for solutions of these complexes in dimethylformamide and dimethylsulfoxide, contained signals attributable to both ligand-based and metal-based redox processes 142). 

Figure 9.1 Formal potentials of oligo(l,l -dihexylferrocenylene)s, 1, obtained by Osteryoung square-wave voltammetry (o), those calculated from the first neighboring site interaction energies ( ) with ii = 15 kJ mol-1 and u2 = 4.5 kJ mol-1, and those calculated from both the first and second neighboring site interaction energies (O)withn = 15 kJmol-1, u2 = 4.5kJmol 1, and w0Xr = -3.8kJmol 1.

Figure 9.5 (a) Osteryoung square-wave voltammogram of 12a in 0.1 M NaBPh4-THF with and without... 

Human blood specimens Pb Centrifuge filter mix filtrate with Hg++/HCl [N/MT] Perform analyses using the Osteryoung square wave stripping voltammetry mode on electrochemical analyzer with glass or PE shrouded carbon disk ultra-microelectrodes [SWSV] [N/MT-SWSV] Feldman et al. 1994... 

If the concentrations of the redox compounds in the solution or at the electrode surface are low, and better sensitivities are needed than those optimal for LSV and SCV, differential pulse (DPV), normal pulse (NPV) and Osteryoung square-wave voltammetries (OSWV) are more suitable [9a, 9b]. They allow better elimination of the capacitive/background currents and, therefore, the measurement of smaller faradic signals becomes easier. This is achieved either by sampling the current at the end of each pulse (OSWV, NPV) (Fig. 10.5.IE and F) or twice at the end and before pulse application (DPV) (Fig. 10.5.ID). 

FIGURE 15.14 Osteryoung square wave voltammograms at the (PDDA/MWNT)5/GC electrode for... 

Figure 7.5. Typical Osteryoung square wave voltammograms of CoOBTPc-SAM modified gold electrodes in pH 4 buffer solutions before (i) and after the addition of (ii) 9.30 x 10 mol dm 3 1.98 x 10 mol dm 3 (iv) 40.5 x 10 mol dm 3 (y) 80.0 x 10 mol...

One of us had previously report Ae Osteryoung Square Wave Voltammetry (OSWV) of an isomer mixture of C78 [23]. At that time we observed what appeared to be two sets of two oxidation peaks eadi, one set being approximately four times as intense... 

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