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Subject scanning rate

We consider again the redox reaction Ox + ze = Red with a solution initially containing only the oxidized form Ox. The electrode is initially subjected to an electrode potential Et where no reaction takes place. For the sake of simplicity, it is assumed that the diffusion coefficients of species Ox and Red are equal, i.e., D = D()s = DRcd. Now, the potential E is linearly increased or decreased with E(t) = Ei vt (v is a potential scan rate, and signs + and represent anodic scan and cathodic scan, respectively.) Under the assumption that the redox couple is reversible, the surface concentrations of Ox and Red, i.e., c()s... [Pg.368]

MCs have also been doped with nitrogen and their stability was investigated [150], These catalysts were subjected to long-term potential cycling (10,000 cycles between 0.5 and 1V vs. RHE, 50 mVs 1 scan rate) and their ECA results were compared to Pt sup-... [Pg.376]

Figure 6. Cathodic current functions (i/v") for CV scans of two waves of [(h -CjHPjCop in CHjCN-ln-Bu NjfPF ) at various scan rates. = [(h -CjHjIjCo) wave = [(h -CjM ljCo)" wave, which is subject to ECE reaction. Figure 6. Cathodic current functions (i/v") for CV scans of two waves of [(h -CjHPjCop in CHjCN-ln-Bu NjfPF ) at various scan rates. = [(h -CjHjIjCo) wave = [(h -CjM ljCo)" wave, which is subject to ECE reaction.
A Pb/PbO/PbS04 electrode system was prepared by potentiostatic oxidation of a Pb electrode in 0.5 M H2SO4 solution at +0.60 V vs Hg/Hg2S04 reference electrode. After this, the system was subjected to potentiodynamic polarization at a scan rate of 10 mV s Figure 2.24 shows the potentiodynamic curves recorded during five potential runs up to 1.450 V [52]. [Pg.66]

The self-assembly of NPQD was electrochemically created on the Au electrode by the following procedure. First the Au electrode was modified with the self-assembly of 4-aminothiophenol (4-ATP) and the 4-ATP-Au electrode was subjected to potential cycling between -0.2 and 0.7 V vs. Ag/AgCl in 0.1 mol L phosphate buffer at a scan rate of 100 mV s (5-7 cycles). The prepared self-assembly was characterized by electrochemical and in situ FTIR techniques. The mixed self-assembly of MNC and NPQD was fabricated by immersing the NPQD-Au electrode into a methanol solution of 0.6 mmol L MNC for 12 h. [Pg.451]

There is also discussion of the E LogI criterion where a graph of potential versus the logarithm of the applied current is plotted. The transition of the steel from anodic to cathodic condition is indicated by a break in the curve. However, the existence of a break and its location can be subjective and the shape of the curve changes with the scan rate. The RP suggests that... [Pg.181]

Figure 4.29 Heating DSC curves for dotriacontane cooled at various scanning rates [41], 1, Original sample not subjected to melting II-V, the sample cooled at 0.05, III 0.5, IV 1,0 and V 10 °C min" ... Figure 4.29 Heating DSC curves for dotriacontane cooled at various scanning rates [41], 1, Original sample not subjected to melting II-V, the sample cooled at 0.05, III 0.5, IV 1,0 and V 10 °C min" ...
Eigure 6.1.4.2 shows the relationship that exists between the range of useable scan rates and electrode radius subject to the condition that ohmic drop is negligible and that the dominant mass transport regime is linear diffusion (9). [Pg.165]

The cyclic voltammetry characteristics of the nitroaniline-containing molecular scale devices were determined to help elucidate the transport mechanism. It was therefore necessary to synthesize thioether 73 that is more stable to hydrolysis and subsequent oxidation than the thioacetate-terminated system (Scheme 3.34). For the synthesis of thioether 73, intermediate 69 was deprotected and Pd/Cu-catalyzed coupled to 72 to form thioether terminated 73. This compound was subjected to cyclic voltammetry that confirmed that the compound was being reduced at -1.7 V and again reduced at -2.3 V (Ag/AgNOs reference electrode, 1.0 M n-tetrabutylammonium tetrafluoroborate in DMF at a scan rate of 100 mV/sec). Of course, there can be no correlation of absolute reduction potentials between the solution-phase and SAM experiments since the environments are grossly different. However, that 73 could undergo a reversible 2-electron reduction was useful in the development of a hypothesis of a mechanism of the transport effect. ... [Pg.121]

The radiofrequency pulses involved in MRI cause thermal heating of the tissues, and are thus subject to FDA limits on the amount of RF power that is transmitted to a subject during a medical scan. The RF power unit is specified as the specific absorption rate (SAR) and is measured in watts per kilogram of body tissue (W/kg tissue). Powers that exceed this level put the subject at risk of tissue damage incurred as a result of the tissue s inability to remove the heat through blood flow. [Pg.940]

Although it s possible to acquire many spectra in rapid succession using pulsed NMR methods, one needs to be aware that the speed with which multiple FIDs can be acquired is still subject to the fact that the nuclei in the sample need to relax between acquisitions (Section 5.1). If successive FIDs are acquired too rapidly, intensity information will be distorted because those nuclei which relax slowly will not be fully relaxed when subsequent scans are acquired and they will contribute less to the resulting signal. To ensure that the signal intensities are accurate, the repetition rate needs to be such that even any slowly relaxing nuclei in the sample are fully relaxed between scans. [Pg.40]


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See also in sourсe #XX -- [ Pg.152 ]




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