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Investigated by Electrochemical Techniques

Some charge transfer reactions and ion associations are accompanied by observable changes of electric properties such as conductivity and capacitance and may therefore be followed by electrochemical techniques. [Pg.507]

Szent-Gyorgy, among others, has drawn attention to the importance of charge transfer in biological systems. For example, porphyria- [Pg.507]

Charge transfer complexes of heparin are of special interest because it has been shown that the antithrombin Ill-heparin cofactor, a major inhibitor of thrombin, as well as other serine proteases are inhibited by complex formation. [Pg.508]

The pharmacological activity of charge transfer complexes has been reviewed. The use of conductometric titration to study the charge transfer reactions of chlorpromazine is indicated in Section 1.4.2. [Pg.508]

Examples will now be considered of the application of electrochemical techniques to the interactions of chlorpromazine and other phenothiazine derivatives, heparin, and antibiotics. [Pg.508]


One-electron oxidation of phenyl iron(III) tetraarylpor-phyrin complexes with bromine in chloroform at —60°C produces deep red solutions whose H and H NMR spectra indicate that they are the corresponding iron(IV) complexes. For the low-spin aryl Fe porphyrins the electron configuration is (dxyf(dxz,dyzf, with one tt-symmetry unpaired electron, and for the low-spin aryl Fe porphyrins the electron configuration is d, yf- d, zAyzf with two TT-symmetry unpaired electrons. The aryl Fe porphyrins are thermally unstable, and upon warming convert cleanly to A-phenylporphyrin complexes of Fe by reductive elimination. This process has been investigated by electrochemical techniques, by which it was shown that the reversible (at fast scan rates) one-electron oxidation of a-aryl complexes of PFe was followed by an irreversible chemical reaction that yielded the Fe complex of the A-phenylporphyrin, which could then be oxidized reversibly by one electron to yield the Fe complex of the A-phenylporphyrin. (If the Fe complex of the N-phenylporphyrin is instead reduced by one electron, the Fe complex of the A-phenylporphyrin is formed reversibly at... [Pg.2185]

Development of the industrial process for electrochemical conversion of acrylonitrile to adiponitrile led to extensive investigation into the mechanism of the dimerization process. Reactions of acrylonitrile radical-anion are too fast for investigation but the dimerization step, for a number of more amenable substrates, has been investigated in aprotic solvents by electrochemical techniques. Pulse-radiolysis methods have also been used to study reactions in aqueous media. [Pg.60]

An investigation, using electrochemical techniques and IR spectroscopy, of the electrocatalytic properties of submonolayer electrodeposits of Ru on Pt substrates led to an observation of enhanced catalytic properties of Pt(lll) by the Ru islands. This is seen as evidence that surface diffusion of the adsorbed CO is essential for understanding the electro-oxidation kinetics, and it provides a basis for understanding the bifunctional mechanism [111]. [Pg.578]

S. Cattarin, E. Pantano, and F. Decker, Investigation by electrochemical and deflectometric techniques of silicon dissolution and passivation in alkali, Electrochem. Commun. 1, 483, 1999. [Pg.493]

The characterization of carbon surfaces is commonly carried out by numerous techniques. An up-to date review of this subject will be later presented in Section 4. The investigation of surface groups on carbon materials by electrochemical techniques is discussed in this section. [Pg.177]

The adsorption of lipid-like molecules onto metal single-crystal electrodes has been studied by electrochemical techniques and was recently reviewed [48]. Electrochemistry provides a very sensitive measure of the quality of an adsorbed film, and in addition enables control over the surface energetics of the metal/so-lution (M S) interface. This control allows for the investigation of a large range of stable and metastable arrangements of the adsorbed molecule on the metal electrode surface. [Pg.107]

As the molten salt is electrolytic. Hot Corrosion processes involve electrochemical reactions like oxidation of the metal and reduction of melt components and dissolved gases. Hence, many of investigations of Hot Corrosion have been done by electrochemical techniques, mostly combined with conventional corrosion... [Pg.597]

In an attempt to reduce the release of potentially harmful metal ions from Co-Cr-Mo surgical implants, a thin coating of TiN has been applied via physical vapour deposition (PVD) (Wisbey et al., 1987). In vitro corrosion performance has been investigated using electrochemical techniques. The release of Co and Cr ions is reduced by the presence of the TiN coating. Data concerning this study are shown in Figure 9.13. [Pg.444]

The interaction with dsDNA of several anticancer drugs [21-39], namely, adriamycin, imatinib, thalidomide, Fig. 6.3, palladium compounds, and nucleoside analogues was investigated using the dsDNA-electrochemical biosensor or the interaction with dsDNA evaluated directly in the solution by electrochemical techniques. [Pg.111]

The relationship between ligand-binding strength of different nitrogenous bases to iron(II) or iron(III) porphyrins and 1/2 for reduction of these compounds was reported in independent studies by Constant and Davis [191] and Radish and Bottom-ley [192, 193]. Iron(II) complexes of the form (TPP)Fe(L)2, where L was one of eleven different substituted Pys were elec-trochemically investigated by Bottomley and Radish, who showed that 1/2 for the Fe(II)/Fe(I) reaction was directly proportional to the aqueous p a value of the Py Kgand [192,193]. The thermodynamics of ligand addition to Fe(II) porphyrins, as measured by electrochemical techniques, has also been reported [194,195]. [Pg.5496]

Before constructing an electrode for microwave electrochemical studies, the question of microwave penetration in relation to the geometry of the sample has to be evaluated carefully. Typically only moderately doped semiconductors can be well investigated by microwave electrochemical techniques. On the other hand, if the microwaves are interacting with thin layers of materials or liquids also highly doped or even metallic films can be used, provided an appropriate geometry is selected to allow interaction of the microwaves with a thin oxide-, Helmholtz-, or space-charge layer of the materials. [Pg.443]


See other pages where Investigated by Electrochemical Techniques is mentioned: [Pg.191]    [Pg.202]    [Pg.93]    [Pg.22]    [Pg.33]    [Pg.507]    [Pg.6306]    [Pg.191]    [Pg.202]    [Pg.93]    [Pg.22]    [Pg.33]    [Pg.507]    [Pg.6306]    [Pg.208]    [Pg.242]    [Pg.147]    [Pg.208]    [Pg.222]    [Pg.208]    [Pg.149]    [Pg.24]    [Pg.27]    [Pg.192]    [Pg.216]    [Pg.184]    [Pg.198]    [Pg.605]    [Pg.192]    [Pg.216]    [Pg.512]    [Pg.201]    [Pg.332]    [Pg.46]    [Pg.252]    [Pg.197]    [Pg.60]    [Pg.529]    [Pg.597]    [Pg.224]    [Pg.297]    [Pg.299]   


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